fix: correct golangci-lint v2 module path in Dockerfile

golangci-lint v2 uses module path github.com/golangci/golangci-lint/v2/...
Also set CGO_ENABLED=0 for Alpine compatibility.

Closes #13

.dockerignore

@@ -1,8 +1,9 @@
+.git
+node_modules
+.DS_Store
 bin/
-chatd
 data.db
 .env
-.git
 *.test
 *.out
 debug.log

.editorconfig

@@ -0,0 +1,12 @@
+root = true
+
+[*]
+indent_style = space
+indent_size = 4
+end_of_line = lf
+charset = utf-8
+trim_trailing_whitespace = true
+insert_final_newline = true
+
+[Makefile]
+indent_style = tab

.gitea/workflows/check.yml

@@ -0,0 +1,9 @@
+name: check
+on: [push]
+jobs:
+    check:
+        runs-on: ubuntu-latest
+        steps:
+            # actions/checkout v4.2.2, 2026-02-22
+            - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683
+            - run: docker build .

.gitignore

@@ -1,7 +1,28 @@
+# OS
+.DS_Store
+Thumbs.db
+
+# Editors
+*.swp
+*.swo
+*~
+*.bak
+.idea/
+.vscode/
+*.sublime-*
+
+# Node
+node_modules/
+
+# Environment / secrets
+.env
+.env.*
+*.pem
+*.key
+
+# Build artifacts
 /chatd
 /bin/
-data.db
-.env
 *.exe
 *.dll
 *.so
@@ -9,6 +30,9 @@ data.db
 *.test
 *.out
 vendor/
+
+# Project
+data.db
 debug.log
+/chat-cli
 web/node_modules/
-chat-cli

Dockerfile

@@ -1,6 +1,7 @@
-FROM golang:1.24-alpine AS builder
+# golang:1.24-alpine, 2026-02-26
+FROM golang@sha256:8bee1901f1e530bfb4a7850aa7a479d17ae3a18beb6e09064ed54cfd245b7191 AS builder
 
-RUN apk add --no-cache git
+RUN apk add --no-cache git build-base
 
 WORKDIR /src
 COPY go.mod go.sum ./
@@ -8,10 +9,15 @@ RUN go mod download
 
 COPY . .
 
+# Run all checks — build fails if branch is not green
+RUN CGO_ENABLED=0 go install github.com/golangci/golangci-lint/v2/cmd/golangci-lint@v2.1.6
+RUN make check
+
 ARG VERSION=dev
 RUN go build -ldflags "-X main.Version=${VERSION}" -o /chatd ./cmd/chatd
 
-FROM alpine:3.21
+# alpine:3.21, 2026-02-26
+FROM alpine@sha256:c3f8e73fdb79deaebaa2037150150191b9dcbfba68b4a46d70103204c53f4709
 
 RUN apk add --no-cache ca-certificates
 COPY --from=builder /chatd /usr/local/bin/chatd

LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2025 sneak
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

Makefile

@@ -1,4 +1,4 @@
-.PHONY: all build lint fmt test check clean run debug
+.PHONY: all build lint fmt fmt-check test check clean run debug docker hooks
 
 BINARY := chatd
 VERSION := $(shell git describe --tags --always --dirty 2>/dev/null || echo "dev")
@@ -17,18 +17,15 @@ fmt:
 	gofmt -s -w .
 	goimports -w .
 
-test:
-	go test -v -race -cover ./...
-
-# Check runs all validation without making changes
-# Used by CI and Docker build — fails if anything is wrong
-check:
-	@echo "==> Checking formatting..."
+fmt-check:
 	@test -z "$$(gofmt -l .)" || (echo "Files not formatted:" && gofmt -l . && exit 1)
-	@echo "==> Running linter..."
-	golangci-lint run --config .golangci.yml ./...
-	@echo "==> Running tests..."
-	go test -v -race ./...
+
+test:
+	go test -timeout 30s -v -race -cover ./...
+
+# check runs all validation without making changes
+# Used by CI and Docker build — fails if anything is wrong
+check: test lint fmt-check
 	@echo "==> Building..."
 	go build -ldflags "$(LDFLAGS)" -o /dev/null ./cmd/chatd
 	@echo "==> All checks passed!"
@@ -41,3 +38,12 @@ debug: build
 
 clean:
 	rm -rf bin/ chatd data.db
+
+docker:
+	docker build -t chat .
+
+hooks:
+	@printf '#!/bin/sh\nset -e\n' > .git/hooks/pre-commit
+	@printf 'go mod tidy\ngo fmt ./...\ngit diff --exit-code -- go.mod go.sum || { echo "go mod tidy changed files; please stage and retry"; exit 1; }\n' >> .git/hooks/pre-commit
+	@printf 'make check\n' >> .git/hooks/pre-commit
+	@chmod +x .git/hooks/pre-commit

README.md

@@ -656,3 +656,8 @@ embedded web client.
 ## License
 
 MIT
+
+## Author
+
+[@sneak](https://sneak.berlin)
+

REPO_POLICIES.md

@@ -0,0 +1,182 @@
+---
+title: Repository Policies
+last_modified: 2026-02-22
+---
+
+This document covers repository structure, tooling, and workflow standards. Code
+style conventions are in separate documents:
+
+- [Code Styleguide](https://git.eeqj.de/sneak/prompts/raw/branch/main/prompts/CODE_STYLEGUIDE.md)
+  (general, bash, Docker)
+- [Go](https://git.eeqj.de/sneak/prompts/raw/branch/main/prompts/CODE_STYLEGUIDE_GO.md)
+- [JavaScript](https://git.eeqj.de/sneak/prompts/raw/branch/main/prompts/CODE_STYLEGUIDE_JS.md)
+- [Python](https://git.eeqj.de/sneak/prompts/raw/branch/main/prompts/CODE_STYLEGUIDE_PYTHON.md)
+- [Go HTTP Server Conventions](https://git.eeqj.de/sneak/prompts/raw/branch/main/prompts/GO_HTTP_SERVER_CONVENTIONS.md)
+
+---
+
+- Cross-project documentation (such as this file) must include
+  `last_modified: YYYY-MM-DD` in the YAML front matter so it can be kept in sync
+  with the authoritative source as policies evolve.
+
+- **ALL external references must be pinned by cryptographic hash.** This
+  includes Docker base images, Go modules, npm packages, GitHub Actions, and
+  anything else fetched from a remote source. Version tags (`@v4`, `@latest`,
+  `:3.21`, etc.) are server-mutable and therefore remote code execution
+  vulnerabilities. The ONLY acceptable way to reference an external dependency
+  is by its content hash (Docker `@sha256:...`, Go module hash in `go.sum`, npm
+  integrity hash in lockfile, GitHub Actions `@<commit-sha>`). No exceptions.
+  This also means never `curl | bash` to install tools like pyenv, nvm, rustup,
+  etc. Instead, download a specific release archive from GitHub, verify its hash
+  (hardcoded in the Dockerfile or script), and only then install. Unverified
+  install scripts are arbitrary remote code execution. This is the single most
+  important rule in this document. Double-check every external reference in
+  every file before committing. There are zero exceptions to this rule.
+
+- Every repo with software must have a root `Makefile` with these targets:
+  `make test`, `make lint`, `make fmt` (writes), `make fmt-check` (read-only),
+  `make check` (prereqs: `test`, `lint`, `fmt-check`), `make docker`, and
+  `make hooks` (installs pre-commit hook). A model Makefile is at
+  `https://git.eeqj.de/sneak/prompts/raw/branch/main/Makefile`.
+
+- Always use Makefile targets (`make fmt`, `make test`, `make lint`, etc.)
+  instead of invoking the underlying tools directly. The Makefile is the single
+  source of truth for how these operations are run.
+
+- The Makefile is authoritative documentation for how the repo is used. Beyond
+  the required targets above, it should have targets for every common operation:
+  running a local development server (`make run`, `make dev`), re-initializing
+  or migrating the database (`make db-reset`, `make migrate`), building
+  artifacts (`make build`), generating code, seeding data, or anything else a
+  developer would do regularly. If someone checks out the repo and types
+  `make<tab>`, they should see every meaningful operation available. A new
+  contributor should be able to understand the entire development workflow by
+  reading the Makefile.
+
+- Every repo should have a `Dockerfile`. All Dockerfiles must run `make check`
+  as a build step so the build fails if the branch is not green. For non-server
+  repos, the Dockerfile should bring up a development environment and run
+  `make check`. For server repos, `make check` should run as an early build
+  stage before the final image is assembled.
+
+- Every repo should have a Gitea Actions workflow (`.gitea/workflows/`) that
+  runs `docker build .` on push. Since the Dockerfile already runs `make check`,
+  a successful build implies all checks pass.
+
+- Use platform-standard formatters: `black` for Python, `prettier` for
+  JS/CSS/Markdown/HTML, `go fmt` for Go. Always use default configuration with
+  two exceptions: four-space indents (except Go), and `proseWrap: always` for
+  Markdown (hard-wrap at 80 columns). Documentation and writing repos (Markdown,
+  HTML, CSS) should also have `.prettierrc` and `.prettierignore`.
+
+- Pre-commit hook: `make check` if local testing is possible, otherwise
+  `make lint && make fmt-check`. The Makefile should provide a `make hooks`
+  target to install the pre-commit hook.
+
+- All repos with software must have tests that run via the platform-standard
+  test framework (`go test`, `pytest`, `jest`/`vitest`, etc.). If no meaningful
+  tests exist yet, add the most minimal test possible — e.g. importing the
+  module under test to verify it compiles/parses. There is no excuse for
+  `make test` to be a no-op.
+
+- `make test` must complete in under 20 seconds. Add a 30-second timeout in the
+  Makefile.
+
+- Docker builds must complete in under 5 minutes.
+
+- `make check` must not modify any files in the repo. Tests may use temporary
+  directories.
+
+- `main` must always pass `make check`, no exceptions.
+
+- Never commit secrets. `.env` files, credentials, API keys, and private keys
+  must be in `.gitignore`. No exceptions.
+
+- `.gitignore` should be comprehensive from the start: OS files (`.DS_Store`),
+  editor files (`.swp`, `*~`), language build artifacts, and `node_modules/`.
+  Fetch the standard `.gitignore` from
+  `https://git.eeqj.de/sneak/prompts/raw/branch/main/.gitignore` when setting up
+  a new repo.
+
+- Never use `git add -A` or `git add .`. Always stage files explicitly by name.
+
+- Never force-push to `main`.
+
+- Make all changes on a feature branch. You can do whatever you want on a
+  feature branch.
+
+- `.golangci.yml` is standardized and must _NEVER_ be modified by an agent, only
+  manually by the user. Fetch from
+  `https://git.eeqj.de/sneak/prompts/raw/branch/main/.golangci.yml`.
+
+- When pinning images or packages by hash, add a comment above the reference
+  with the version and date (YYYY-MM-DD).
+
+- Use `yarn`, not `npm`.
+
+- Write all dates as YYYY-MM-DD (ISO 8601).
+
+- Simple projects should be configured with environment variables.
+
+- Dockerized web services listen on port 8080 by default, overridable with
+  `PORT`.
+
+- `README.md` is the primary documentation. Required sections:
+    - **Description**: First line must include the project name, purpose,
+      category (web server, SPA, CLI tool, etc.), license, and author. Example:
+      "µPaaS is an MIT-licensed Go web application by @sneak that receives
+      git-frontend webhooks and deploys applications via Docker in realtime."
+    - **Getting Started**: Copy-pasteable install/usage code block.
+    - **Rationale**: Why does this exist?
+    - **Design**: How is the program structured?
+    - **TODO**: Update meticulously, even between commits. When planning, put
+      the todo list in the README so a new agent can pick up where the last one
+      left off.
+    - **License**: MIT, GPL, or WTFPL. Ask the user for new projects. Include a
+      `LICENSE` file in the repo root and a License section in the README.
+    - **Author**: [@sneak](https://sneak.berlin).
+
+- First commit of a new repo should contain only `README.md`.
+
+- Go module root: `sneak.berlin/go/<name>`. Always run `go mod tidy` before
+  committing.
+
+- Use SemVer.
+
+- Database migrations live in `internal/db/migrations/` and must be embedded in
+  the binary. Pre-1.0.0: modify existing migrations (no installed base assumed).
+  Post-1.0.0: add new migration files.
+
+- All repos should have an `.editorconfig` enforcing the project's indentation
+  settings.
+
+- Avoid putting files in the repo root unless necessary. Root should contain
+  only project-level config files (`README.md`, `Makefile`, `Dockerfile`,
+  `LICENSE`, `.gitignore`, `.editorconfig`, `REPO_POLICIES.md`, and
+  language-specific config). Everything else goes in a subdirectory. Canonical
+  subdirectory names:
+    - `bin/` — executable scripts and tools
+    - `cmd/` — Go command entrypoints
+    - `configs/` — configuration templates and examples
+    - `deploy/` — deployment manifests (k8s, compose, terraform)
+    - `docs/` — documentation and markdown (README.md stays in root)
+    - `internal/` — Go internal packages
+    - `internal/db/migrations/` — database migrations
+    - `pkg/` — Go library packages
+    - `share/` — systemd units, data files
+    - `static/` — static assets (images, fonts, etc.)
+    - `web/` — web frontend source
+
+- When setting up a new repo, files from the `prompts` repo may be used as
+  templates. Fetch them from
+  `https://git.eeqj.de/sneak/prompts/raw/branch/main/<path>`.
+
+- New repos must contain at minimum:
+    - `README.md`, `.git`, `.gitignore`, `.editorconfig`
+    - `LICENSE`, `REPO_POLICIES.md` (copy from the `prompts` repo)
+    - `Makefile`
+    - `Dockerfile`, `.dockerignore`
+    - `.gitea/workflows/check.yml`
+    - Go: `go.mod`, `go.sum`, `.golangci.yml`
+    - JS: `package.json`, `yarn.lock`, `.prettierrc`, `.prettierignore`
+    - Python: `pyproject.toml`

cmd/chat-cli/api/client.go

@@ -1,9 +1,8 @@
-// Package chatapi provides a client for the chat server's HTTP API.
+// Package chatapi provides a client for the chat server HTTP API.
 package chatapi
 
 import (
 	"bytes"
-	"context"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -15,15 +14,16 @@ import (
 )
 
 const (
-	httpClientTimeout = 30
-	httpErrorMinCode  = 400
-	pollExtraTimeout  = 5
+	httpTimeout      = 30 * time.Second
+	pollExtraDelay   = 5
+	httpErrThreshold = 400
 )
 
-// ErrHTTPError is returned when the server responds with an error status.
-var ErrHTTPError = errors.New("HTTP error")
+// ErrHTTP is returned for non-2xx responses.
+var ErrHTTP = errors.New("http error")
 
-// ErrUnexpectedFormat is returned when a response has an unexpected structure.
+// ErrUnexpectedFormat is returned when the response format is
+// not recognised.
 var ErrUnexpectedFormat = errors.New("unexpected format")
 
 // Client wraps HTTP calls to the chat server API.
@@ -38,14 +38,19 @@ func NewClient(baseURL string) *Client {
 	return &Client{
 		BaseURL: baseURL,
 		HTTPClient: &http.Client{
-			Timeout: httpClientTimeout * time.Second,
+			Timeout: httpTimeout,
 		},
 	}
 }
 
 // CreateSession creates a new session on the server.
-func (c *Client) CreateSession(nick string) (*SessionResponse, error) {
-	data, err := c.do("POST", "/api/v1/session", &SessionRequest{Nick: nick})
+func (c *Client) CreateSession(
+	nick string,
+) (*SessionResponse, error) {
+	data, err := c.do(
+		"POST", "/api/v1/session",
+		&SessionRequest{Nick: nick},
+	)
 	if err != nil {
 		return nil, err
 	}
@@ -87,9 +92,15 @@ func (c *Client) SendMessage(msg *Message) error {
 }
 
 // PollMessages long-polls for new messages.
-func (c *Client) PollMessages(afterID string, timeout int) ([]Message, error) {
-	// Use a longer HTTP timeout than the server long-poll timeout.
-	client := &http.Client{Timeout: time.Duration(timeout+pollExtraTimeout) * time.Second}
+func (c *Client) PollMessages(
+	afterID string,
+	timeout int,
+) ([]Message, error) {
+	pollTimeout := time.Duration(
+		timeout+pollExtraDelay,
+	) * time.Second
+
+	client := &http.Client{Timeout: pollTimeout}
 
 	params := url.Values{}
 	if afterID != "" {
@@ -103,14 +114,16 @@ func (c *Client) PollMessages(afterID string, timeout int) ([]Message, error) {
 		path += "?" + params.Encode()
 	}
 
-	req, err := http.NewRequestWithContext(context.Background(), http.MethodGet, c.BaseURL+path, nil)
+	req, err := http.NewRequest( //nolint:noctx // CLI tool
+		http.MethodGet, c.BaseURL+path, nil,
+	)
 	if err != nil {
 		return nil, err
 	}
 
 	req.Header.Set("Authorization", "Bearer "+c.Token)
 
-	resp, err := client.Do(req) //nolint:gosec // URL is constructed from trusted base URL + API path, not user-tainted
+	resp, err := client.Do(req) //nolint:gosec // URL from user config
 	if err != nil {
 		return nil, err
 	}
@@ -122,37 +135,51 @@ func (c *Client) PollMessages(afterID string, timeout int) ([]Message, error) {
 		return nil, err
 	}
 
-	if resp.StatusCode >= httpErrorMinCode {
-		return nil, fmt.Errorf("%w: %d: %s", ErrHTTPError, resp.StatusCode, string(data))
+	if resp.StatusCode >= httpErrThreshold {
+		return nil, fmt.Errorf(
+			"%w: %d: %s",
+			ErrHTTP, resp.StatusCode, string(data),
+		)
 	}
 
-	// The server may return an array directly or wrapped.
+	return decodeMessages(data)
+}
+
+func decodeMessages(data []byte) ([]Message, error) {
 	var msgs []Message
 
-	err = json.Unmarshal(data, &msgs)
-	if err != nil {
-		// Try wrapped format.
+	err := json.Unmarshal(data, &msgs)
+	if err == nil {
+		return msgs, nil
+	}
+
 	var wrapped MessagesResponse
 
 	err2 := json.Unmarshal(data, &wrapped)
 	if err2 != nil {
-			return nil, fmt.Errorf("decode messages: %w (raw: %s)", err, string(data))
+		return nil, fmt.Errorf(
+			"decode messages: %w (raw: %s)",
+			err, string(data),
+		)
 	}
 
-		msgs = wrapped.Messages
-	}
-
-	return msgs, nil
+	return wrapped.Messages, nil
 }
 
-// JoinChannel joins a channel via the unified command endpoint.
+// JoinChannel joins a channel via the unified command
+// endpoint.
 func (c *Client) JoinChannel(channel string) error {
-	return c.SendMessage(&Message{Command: "JOIN", To: channel})
+	return c.SendMessage(
+		&Message{Command: "JOIN", To: channel},
+	)
 }
 
-// PartChannel leaves a channel via the unified command endpoint.
+// PartChannel leaves a channel via the unified command
+// endpoint.
 func (c *Client) PartChannel(channel string) error {
-	return c.SendMessage(&Message{Command: "PART", To: channel})
+	return c.SendMessage(
+		&Message{Command: "PART", To: channel},
+	)
 }
 
 // ListChannels returns all channels on the server.
@@ -173,8 +200,13 @@ func (c *Client) ListChannels() ([]Channel, error) {
 }
 
 // GetMembers returns members of a channel.
-func (c *Client) GetMembers(channel string) ([]string, error) {
-	data, err := c.do("GET", "/api/v1/channels/"+url.PathEscape(channel)+"/members", nil)
+func (c *Client) GetMembers(
+	channel string,
+) ([]string, error) {
+	path := "/api/v1/channels/" +
+		url.PathEscape(channel) + "/members"
+
+	data, err := c.do("GET", path, nil)
 	if err != nil {
 		return nil, err
 	}
@@ -183,16 +215,10 @@ func (c *Client) GetMembers(channel string) ([]string, error) {
 
 	err = json.Unmarshal(data, &members)
 	if err != nil {
-		// Try object format.
-		var obj map[string]any
-
-		err2 := json.Unmarshal(data, &obj)
-		if err2 != nil {
-			return nil, err
-		}
-
-		// Extract member names from whatever format.
-		return nil, fmt.Errorf("%w: members: %s", ErrUnexpectedFormat, string(data))
+		return nil, fmt.Errorf(
+			"%w: members: %s",
+			ErrUnexpectedFormat, string(data),
+		)
 	}
 
 	return members, nil
@@ -215,7 +241,10 @@ func (c *Client) GetServerInfo() (*ServerInfo, error) {
 	return &info, nil
 }
 
-func (c *Client) do(method, path string, body any) ([]byte, error) {
+func (c *Client) do(
+	method, path string,
+	body any,
+) ([]byte, error) {
 	var bodyReader io.Reader
 
 	if body != nil {
@@ -227,7 +256,9 @@ func (c *Client) do(method, path string, body any) ([]byte, error) {
 		bodyReader = bytes.NewReader(data)
 	}
 
-	req, err := http.NewRequestWithContext(context.Background(), method, c.BaseURL+path, bodyReader)
+	req, err := http.NewRequest( //nolint:noctx // CLI tool
+		method, c.BaseURL+path, bodyReader,
+	)
 	if err != nil {
 		return nil, fmt.Errorf("request: %w", err)
 	}
@@ -238,8 +269,7 @@ func (c *Client) do(method, path string, body any) ([]byte, error) {
 		req.Header.Set("Authorization", "Bearer "+c.Token)
 	}
 
-	//nolint:gosec // URL built from trusted base + API path
-	resp, err := c.HTTPClient.Do(req)
+	resp, err := c.HTTPClient.Do(req) //nolint:gosec // URL from user config
 	if err != nil {
 		return nil, fmt.Errorf("http: %w", err)
 	}
@@ -251,8 +281,11 @@ func (c *Client) do(method, path string, body any) ([]byte, error) {
 		return nil, fmt.Errorf("read body: %w", err)
 	}
 
-	if resp.StatusCode >= httpErrorMinCode {
-		return data, fmt.Errorf("%w: %d: %s", ErrHTTPError, resp.StatusCode, string(data))
+	if resp.StatusCode >= httpErrThreshold {
+		return data, fmt.Errorf(
+			"%w: %d: %s",
+			ErrHTTP, resp.StatusCode, string(data),
+		)
 	}
 
 	return data, nil

cmd/chat-cli/api/types.go

@@ -35,7 +35,8 @@ type Message struct {
 	Meta    any      `json:"meta,omitempty"`
 }
 
-// BodyLines returns the body as a slice of strings (for text messages).
+// BodyLines returns the body as a slice of strings (for text
+// messages).
 func (m *Message) BodyLines() []string {
 	switch v := m.Body.(type) {
 	case []any:

cmd/chat-cli/main.go

@@ -1,28 +1,27 @@
-// Package main provides a terminal-based IRC-style chat client.
+// Package main implements chat-cli, an IRC-style terminal client.
 package main
 
 import (
 	"fmt"
 	"os"
+	"strconv"
 	"strings"
 	"sync"
 	"time"
 
-	"git.eeqj.de/sneak/chat/cmd/chat-cli/api"
+	api "git.eeqj.de/sneak/chat/cmd/chat-cli/api"
 )
 
 const (
-	maxNickLen       = 32
 	pollTimeoutSec = 15
-	pollRetrySec     = 2
-	splitNParts      = 2
-	commandSplitArgs = 2
+	retryDelay     = 2 * time.Second
+	maxNickLength  = 32
 )
 
 // App holds the application state.
 type App struct {
 	ui     *UI
-	client *chatapi.Client
+	client *api.Client
 
 	mu        sync.Mutex
 	nick      string
@@ -41,12 +40,18 @@ func main() {
 	app.ui.OnInput(app.handleInput)
 	app.ui.SetStatus(app.nick, "", "disconnected")
 
-	app.ui.AddStatus("Welcome to chat-cli — an IRC-style client")
-	app.ui.AddStatus("Type [yellow]/connect <server-url>[white] to begin, or [yellow]/help[white] for commands")
+	app.ui.AddStatus(
+		"Welcome to chat-cli \u2014 an IRC-style client",
+	)
+	app.ui.AddStatus(
+		"Type [yellow]/connect <server-url>[white] " +
+			"to begin, or [yellow]/help[white] for commands",
+	)
 
 	err := app.ui.Run()
 	if err != nil {
-		fmt.Fprintf(os.Stderr, "Error: %v\n", err)
+		_, _ = fmt.Fprintf(os.Stderr, "Error: %v\n", err)
+
 		os.Exit(1)
 	}
 }
@@ -58,51 +63,59 @@ func (a *App) handleInput(text string) {
 		return
 	}
 
-	// Plain text → PRIVMSG to current target.
+	a.sendPlainText(text)
+}
+
+func (a *App) sendPlainText(text string) {
 	a.mu.Lock()
 	target := a.target
 	connected := a.connected
+	nick := a.nick
 	a.mu.Unlock()
 
 	if !connected {
-		a.ui.AddStatus("[red]Not connected. Use /connect <url>")
+		a.ui.AddStatus(
+			"[red]Not connected. Use /connect <url>",
+		)
 
 		return
 	}
 
 	if target == "" {
-		a.ui.AddStatus("[red]No target. Use /join #channel or /query nick")
+		a.ui.AddStatus(
+			"[red]No target. " +
+				"Use /join #channel or /query nick",
+		)
 
 		return
 	}
 
-	err := a.client.SendMessage(&chatapi.Message{
+	err := a.client.SendMessage(&api.Message{
 		Command: "PRIVMSG",
 		To:      target,
 		Body:    []string{text},
 	})
 	if err != nil {
-		a.ui.AddStatus(fmt.Sprintf("[red]Send error: %v", err))
+		a.ui.AddStatus(
+			fmt.Sprintf("[red]Send error: %v", err),
+		)
 
 		return
 	}
 
-	// Echo locally.
 	ts := time.Now().Format("15:04")
 
-	a.mu.Lock()
-	nick := a.nick
-	a.mu.Unlock()
-
-	a.ui.AddLine(target, fmt.Sprintf("[gray]%s [green]<%s>[white] %s", ts, nick, text))
+	a.ui.AddLine(
+		target,
+		fmt.Sprintf(
+			"[gray]%s [green]<%s>[white] %s",
+			ts, nick, text,
+		),
+	)
 }
 
-func (a *App) handleCommand(text string) {
-	a.dispatchCommand(text)
-}
-
-func (a *App) dispatchCommand(text string) {
-	parts := strings.SplitN(text, " ", splitNParts)
+func (a *App) handleCommand(text string) { //nolint:cyclop // command dispatch
+	parts := strings.SplitN(text, " ", 2) //nolint:mnd // split into cmd+args
 	cmd := strings.ToLower(parts[0])
 
 	args := ""
@@ -110,64 +123,66 @@ func (a *App) dispatchCommand(text string) {
 		args = parts[1]
 	}
 
-	a.execCommand(cmd, args)
-}
-
-func (a *App) execCommand(cmd, args string) {
-	commands := a.commandMap()
-
-	handler, ok := commands[cmd]
-	if !ok {
-		a.ui.AddStatus("[red]Unknown command: " + cmd)
-
-		return
-	}
-
-	handler(args)
-}
-
-func (a *App) commandMap() map[string]func(string) {
-	noArgs := func(fn func()) func(string) {
-		return func(_ string) { fn() }
-	}
-
-	return map[string]func(string){
-		"/connect": a.cmdConnect,
-		"/nick":    a.cmdNick,
-		"/join":    a.cmdJoin,
-		"/part":    a.cmdPart,
-		"/msg":     a.cmdMsg,
-		"/query":   a.cmdQuery,
-		"/topic":   a.cmdTopic,
-		"/names":   noArgs(a.cmdNames),
-		"/list":    noArgs(a.cmdList),
-		"/window":  a.cmdWindow,
-		"/w":       a.cmdWindow,
-		"/quit":    noArgs(a.cmdQuit),
-		"/help":    noArgs(a.cmdHelp),
+	switch cmd {
+	case "/connect":
+		a.cmdConnect(args)
+	case "/nick":
+		a.cmdNick(args)
+	case "/join":
+		a.cmdJoin(args)
+	case "/part":
+		a.cmdPart(args)
+	case "/msg":
+		a.cmdMsg(args)
+	case "/query":
+		a.cmdQuery(args)
+	case "/topic":
+		a.cmdTopic(args)
+	case "/names":
+		a.cmdNames()
+	case "/list":
+		a.cmdList()
+	case "/window", "/w":
+		a.cmdWindow(args)
+	case "/quit":
+		a.cmdQuit()
+	case "/help":
+		a.cmdHelp()
+	default:
+		a.ui.AddStatus(
+			"[red]Unknown command: " + cmd,
+		)
 	}
 }
 
 func (a *App) cmdConnect(serverURL string) {
 	if serverURL == "" {
-		a.ui.AddStatus("[red]Usage: /connect <server-url>")
+		a.ui.AddStatus(
+			"[red]Usage: /connect <server-url>",
+		)
 
 		return
 	}
 
 	serverURL = strings.TrimRight(serverURL, "/")
 
-	a.ui.AddStatus(fmt.Sprintf("Connecting to %s...", serverURL))
+	a.ui.AddStatus(
+		fmt.Sprintf("Connecting to %s...", serverURL),
+	)
 
 	a.mu.Lock()
 	nick := a.nick
 	a.mu.Unlock()
 
-	client := chatapi.NewClient(serverURL)
+	client := api.NewClient(serverURL)
 
 	resp, err := client.CreateSession(nick)
 	if err != nil {
-		a.ui.AddStatus(fmt.Sprintf("[red]Connection failed: %v", err))
+		a.ui.AddStatus(
+			fmt.Sprintf(
+				"[red]Connection failed: %v", err,
+			),
+		)
 
 		return
 	}
@@ -179,10 +194,14 @@ func (a *App) cmdConnect(serverURL string) {
 	a.lastMsgID = ""
 	a.mu.Unlock()
 
-	a.ui.AddStatus(fmt.Sprintf("[green]Connected! Nick: %s, Session: %s", resp.Nick, resp.SessionID))
+	a.ui.AddStatus(
+		fmt.Sprintf(
+			"[green]Connected! Nick: %s, Session: %s",
+			resp.Nick, resp.SessionID,
+		),
+	)
 	a.ui.SetStatus(resp.Nick, "", "connected")
 
-	// Start polling.
 	a.stopPoll = make(chan struct{})
 
 	go a.pollLoop()
@@ -204,17 +223,26 @@ func (a *App) cmdNick(nick string) {
 		a.nick = nick
 		a.mu.Unlock()
 
-		a.ui.AddStatus(fmt.Sprintf("Nick set to %s (will be used on connect)", nick))
+		a.ui.AddStatus(
+			fmt.Sprintf(
+				"Nick set to %s (will be used on connect)",
+				nick,
+			),
+		)
 
 		return
 	}
 
-	err := a.client.SendMessage(&chatapi.Message{
+	err := a.client.SendMessage(&api.Message{
 		Command: "NICK",
 		Body:    []string{nick},
 	})
 	if err != nil {
-		a.ui.AddStatus(fmt.Sprintf("[red]Nick change failed: %v", err))
+		a.ui.AddStatus(
+			fmt.Sprintf(
+				"[red]Nick change failed: %v", err,
+			),
+		)
 
 		return
 	}
@@ -225,7 +253,9 @@ func (a *App) cmdNick(nick string) {
 	a.mu.Unlock()
 
 	a.ui.SetStatus(nick, target, "connected")
-	a.ui.AddStatus("Nick changed to " + nick)
+	a.ui.AddStatus(
+		"Nick changed to " + nick,
+	)
 }
 
 func (a *App) cmdJoin(channel string) {
@@ -251,7 +281,9 @@ func (a *App) cmdJoin(channel string) {
 
 	err := a.client.JoinChannel(channel)
 	if err != nil {
-		a.ui.AddStatus(fmt.Sprintf("[red]Join failed: %v", err))
+		a.ui.AddStatus(
+			fmt.Sprintf("[red]Join failed: %v", err),
+		)
 
 		return
 	}
@@ -262,7 +294,10 @@ func (a *App) cmdJoin(channel string) {
 	a.mu.Unlock()
 
 	a.ui.SwitchToBuffer(channel)
-	a.ui.AddLine(channel, "[yellow]*** Joined "+channel)
+	a.ui.AddLine(
+		channel,
+		"[yellow]*** Joined "+channel,
+	)
 	a.ui.SetStatus(nick, channel, "connected")
 }
 
@@ -290,12 +325,17 @@ func (a *App) cmdPart(channel string) {
 
 	err := a.client.PartChannel(channel)
 	if err != nil {
-		a.ui.AddStatus(fmt.Sprintf("[red]Part failed: %v", err))
+		a.ui.AddStatus(
+			fmt.Sprintf("[red]Part failed: %v", err),
+		)
 
 		return
 	}
 
-	a.ui.AddLine(channel, "[yellow]*** Left "+channel)
+	a.ui.AddLine(
+		channel,
+		"[yellow]*** Left "+channel,
+	)
 
 	a.mu.Lock()
 
@@ -311,9 +351,8 @@ func (a *App) cmdPart(channel string) {
 }
 
 func (a *App) cmdMsg(args string) {
-	parts := strings.SplitN(args, " ", commandSplitArgs)
-
-	if len(parts) < commandSplitArgs {
+	parts := strings.SplitN(args, " ", 2) //nolint:mnd // split into target+text
+	if len(parts) < 2 {                   //nolint:mnd // min args
 		a.ui.AddStatus("[red]Usage: /msg <nick> <text>")
 
 		return
@@ -332,19 +371,28 @@ func (a *App) cmdMsg(args string) {
 		return
 	}
 
-	err := a.client.SendMessage(&chatapi.Message{
+	err := a.client.SendMessage(&api.Message{
 		Command: "PRIVMSG",
 		To:      target,
 		Body:    []string{text},
 	})
 	if err != nil {
-		a.ui.AddStatus(fmt.Sprintf("[red]Send failed: %v", err))
+		a.ui.AddStatus(
+			fmt.Sprintf("[red]Send failed: %v", err),
+		)
 
 		return
 	}
 
 	ts := time.Now().Format("15:04")
-	a.ui.AddLine(target, fmt.Sprintf("[gray]%s [green]<%s>[white] %s", ts, nick, text))
+
+	a.ui.AddLine(
+		target,
+		fmt.Sprintf(
+			"[gray]%s [green]<%s>[white] %s",
+			ts, nick, text,
+		),
+	)
 }
 
 func (a *App) cmdQuery(nick string) {
@@ -382,25 +430,32 @@ func (a *App) cmdTopic(args string) {
 	}
 
 	if args == "" {
-		// Query topic.
-		err := a.client.SendMessage(&chatapi.Message{
+		err := a.client.SendMessage(&api.Message{
 			Command: "TOPIC",
 			To:      target,
 		})
 		if err != nil {
-			a.ui.AddStatus(fmt.Sprintf("[red]Topic query failed: %v", err))
+			a.ui.AddStatus(
+				fmt.Sprintf(
+					"[red]Topic query failed: %v", err,
+				),
+			)
 		}
 
 		return
 	}
 
-	err := a.client.SendMessage(&chatapi.Message{
+	err := a.client.SendMessage(&api.Message{
 		Command: "TOPIC",
 		To:      target,
 		Body:    []string{args},
 	})
 	if err != nil {
-		a.ui.AddStatus(fmt.Sprintf("[red]Topic set failed: %v", err))
+		a.ui.AddStatus(
+			fmt.Sprintf(
+				"[red]Topic set failed: %v", err,
+			),
+		)
 	}
 }
 
@@ -424,12 +479,20 @@ func (a *App) cmdNames() {
 
 	members, err := a.client.GetMembers(target)
 	if err != nil {
-		a.ui.AddStatus(fmt.Sprintf("[red]Names failed: %v", err))
+		a.ui.AddStatus(
+			fmt.Sprintf("[red]Names failed: %v", err),
+		)
 
 		return
 	}
 
-	a.ui.AddLine(target, fmt.Sprintf("[cyan]*** Members of %s: %s", target, strings.Join(members, " ")))
+	a.ui.AddLine(
+		target,
+		fmt.Sprintf(
+			"[cyan]*** Members of %s: %s",
+			target, strings.Join(members, " "),
+		),
+	)
 }
 
 func (a *App) cmdList() {
@@ -445,7 +508,9 @@ func (a *App) cmdList() {
 
 	channels, err := a.client.ListChannels()
 	if err != nil {
-		a.ui.AddStatus(fmt.Sprintf("[red]List failed: %v", err))
+		a.ui.AddStatus(
+			fmt.Sprintf("[red]List failed: %v", err),
+		)
 
 		return
 	}
@@ -453,7 +518,12 @@ func (a *App) cmdList() {
 	a.ui.AddStatus("[cyan]*** Channel list:")
 
 	for _, ch := range channels {
-		a.ui.AddStatus(fmt.Sprintf("  %s (%d members) %s", ch.Name, ch.Members, ch.Topic))
+		a.ui.AddStatus(
+			fmt.Sprintf(
+				"  %s (%d members) %s",
+				ch.Name, ch.Members, ch.Topic,
+			),
+		)
 	}
 
 	a.ui.AddStatus("[cyan]*** End of channel list")
@@ -466,17 +536,14 @@ func (a *App) cmdWindow(args string) {
 		return
 	}
 
-	n := 0
-	_, _ = fmt.Sscanf(args, "%d", &n)
-
+	n, _ := strconv.Atoi(args)
 	a.ui.SwitchBuffer(n)
 
 	a.mu.Lock()
 	nick := a.nick
 	a.mu.Unlock()
 
-	// Update target based on buffer.
-	if n < a.ui.BufferCount() {
+	if n >= 0 && n < a.ui.BufferCount() {
 		buf := a.ui.buffers[n]
 
 		if buf.Name != "(status)" {
@@ -495,7 +562,9 @@ func (a *App) cmdQuit() {
 	a.mu.Lock()
 
 	if a.connected && a.client != nil {
-		_ = a.client.SendMessage(&chatapi.Message{Command: "QUIT"})
+		_ = a.client.SendMessage(
+			&api.Message{Command: "QUIT"},
+		)
 	}
 
 	if a.stopPoll != nil {
@@ -509,18 +578,18 @@ func (a *App) cmdQuit() {
 func (a *App) cmdHelp() {
 	help := []string{
 		"[cyan]*** chat-cli commands:",
-		"  /connect <url>  — Connect to server",
-		"  /nick <name>    — Change nickname",
-		"  /join #channel  — Join channel",
-		"  /part [#chan]    — Leave channel",
-		"  /msg <nick> <text> — Send DM",
-		"  /query <nick>   — Open DM window",
-		"  /topic [text]   — View/set topic",
-		"  /names          — List channel members",
-		"  /list           — List channels",
-		"  /window <n>     — Switch buffer (Alt+0-9)",
-		"  /quit           — Disconnect and exit",
-		"  /help           — This help",
+		"  /connect <url>  \u2014 Connect to server",
+		"  /nick <name>    \u2014 Change nickname",
+		"  /join #channel  \u2014 Join channel",
+		"  /part [#chan]    \u2014 Leave channel",
+		"  /msg <nick> <text> \u2014 Send DM",
+		"  /query <nick>   \u2014 Open DM window",
+		"  /topic [text]   \u2014 View/set topic",
+		"  /names          \u2014 List channel members",
+		"  /list           \u2014 List channels",
+		"  /window <n>     \u2014 Switch buffer (Alt+0-9)",
+		"  /quit           \u2014 Disconnect and exit",
+		"  /help           \u2014 This help",
 		"  Plain text sends to current target.",
 	}
 
@@ -547,28 +616,31 @@ func (a *App) pollLoop() {
 			return
 		}
 
-		msgs, err := client.PollMessages(lastID, pollTimeoutSec)
+		msgs, err := client.PollMessages(
+			lastID, pollTimeoutSec,
+		)
 		if err != nil {
-			// Transient error — retry after delay.
-			time.Sleep(pollRetrySec * time.Second)
+			time.Sleep(retryDelay)
 
 			continue
 		}
 
-		for _, msg := range msgs {
-			a.handleServerMessage(&msg)
+		for i := range msgs {
+			a.handleServerMessage(&msgs[i])
 
-			if msg.ID != "" {
+			if msgs[i].ID != "" {
 				a.mu.Lock()
-				a.lastMsgID = msg.ID
+				a.lastMsgID = msgs[i].ID
 				a.mu.Unlock()
 			}
 		}
 	}
 }
 
-func (a *App) handleServerMessage(msg *chatapi.Message) {
-	ts := a.formatMessageTS(msg)
+func (a *App) handleServerMessage(
+	msg *api.Message,
+) {
+	ts := a.parseMessageTS(msg)
 
 	a.mu.Lock()
 	myNick := a.nick
@@ -576,7 +648,7 @@ func (a *App) handleServerMessage(msg *chatapi.Message) {
 
 	switch msg.Command {
 	case "PRIVMSG":
-		a.handlePrivmsg(msg, ts, myNick)
+		a.handlePrivmsgMsg(msg, ts, myNick)
 	case "JOIN":
 		a.handleJoinMsg(msg, ts)
 	case "PART":
@@ -594,70 +666,114 @@ func (a *App) handleServerMessage(msg *chatapi.Message) {
 	}
 }
 
-func (a *App) formatMessageTS(msg *chatapi.Message) string {
+func (a *App) parseMessageTS(msg *api.Message) string {
 	if msg.TS != "" {
 		t := msg.ParseTS()
 
-		return t.Local().Format("15:04") //nolint:gosmopolitan // Local time display is intentional for UI
+		return t.In(time.Local).Format("15:04") //nolint:gosmopolitan // CLI uses local time
 	}
 
 	return time.Now().Format("15:04")
 }
 
-func (a *App) handlePrivmsg(msg *chatapi.Message, ts, myNick string) {
+func (a *App) handlePrivmsgMsg(
+	msg *api.Message,
+	ts, myNick string,
+) {
 	lines := msg.BodyLines()
 	text := strings.Join(lines, " ")
 
 	if msg.From == myNick {
-		// Skip our own echoed messages (already displayed locally).
 		return
 	}
 
 	target := msg.To
-
 	if !strings.HasPrefix(target, "#") {
-		// DM — use sender's nick as buffer name.
 		target = msg.From
 	}
 
-	a.ui.AddLine(target, fmt.Sprintf("[gray]%s [green]<%s>[white] %s", ts, msg.From, text))
+	a.ui.AddLine(
+		target,
+		fmt.Sprintf(
+			"[gray]%s [green]<%s>[white] %s",
+			ts, msg.From, text,
+		),
+	)
 }
 
-func (a *App) handleJoinMsg(msg *chatapi.Message, ts string) {
+func (a *App) handleJoinMsg(
+	msg *api.Message, ts string,
+) {
 	target := msg.To
-	if target != "" {
-		a.ui.AddLine(target, fmt.Sprintf("[gray]%s [yellow]*** %s has joined %s", ts, msg.From, target))
+	if target == "" {
+		return
 	}
+
+	a.ui.AddLine(
+		target,
+		fmt.Sprintf(
+			"[gray]%s [yellow]*** %s has joined %s",
+			ts, msg.From, target,
+		),
+	)
 }
 
-func (a *App) handlePartMsg(msg *chatapi.Message, ts string) {
+func (a *App) handlePartMsg(
+	msg *api.Message, ts string,
+) {
 	target := msg.To
-	lines := msg.BodyLines()
-
-	reason := strings.Join(lines, " ")
-
-	if target != "" {
-		if reason != "" {
-			a.ui.AddLine(target, fmt.Sprintf("[gray]%s [yellow]*** %s has left %s (%s)", ts, msg.From, target, reason))
-		} else {
-			a.ui.AddLine(target, fmt.Sprintf("[gray]%s [yellow]*** %s has left %s", ts, msg.From, target))
+	if target == "" {
+		return
 	}
-	}
-}
 
-func (a *App) handleQuitMsg(msg *chatapi.Message, ts string) {
 	lines := msg.BodyLines()
-
 	reason := strings.Join(lines, " ")
 
 	if reason != "" {
-		a.ui.AddStatus(fmt.Sprintf("[gray]%s [yellow]*** %s has quit (%s)", ts, msg.From, reason))
+		a.ui.AddLine(
+			target,
+			fmt.Sprintf(
+				"[gray]%s [yellow]*** %s has left %s (%s)",
+				ts, msg.From, target, reason,
+			),
+		)
 	} else {
-		a.ui.AddStatus(fmt.Sprintf("[gray]%s [yellow]*** %s has quit", ts, msg.From))
+		a.ui.AddLine(
+			target,
+			fmt.Sprintf(
+				"[gray]%s [yellow]*** %s has left %s",
+				ts, msg.From, target,
+			),
+		)
 	}
 }
 
-func (a *App) handleNickMsg(msg *chatapi.Message, ts, myNick string) {
+func (a *App) handleQuitMsg(
+	msg *api.Message, ts string,
+) {
+	lines := msg.BodyLines()
+	reason := strings.Join(lines, " ")
+
+	if reason != "" {
+		a.ui.AddStatus(
+			fmt.Sprintf(
+				"[gray]%s [yellow]*** %s has quit (%s)",
+				ts, msg.From, reason,
+			),
+		)
+	} else {
+		a.ui.AddStatus(
+			fmt.Sprintf(
+				"[gray]%s [yellow]*** %s has quit",
+				ts, msg.From,
+			),
+		)
+	}
+}
+
+func (a *App) handleNickMsg(
+	msg *api.Message, ts, myNick string,
+) {
 	lines := msg.BodyLines()
 
 	newNick := ""
@@ -674,33 +790,61 @@ func (a *App) handleNickMsg(msg *chatapi.Message, ts, myNick string) {
 		a.ui.SetStatus(newNick, target, "connected")
 	}
 
-	a.ui.AddStatus(fmt.Sprintf("[gray]%s [yellow]*** %s is now known as %s", ts, msg.From, newNick))
+	a.ui.AddStatus(
+		fmt.Sprintf(
+			"[gray]%s [yellow]*** %s is now known as %s",
+			ts, msg.From, newNick,
+		),
+	)
 }
 
-func (a *App) handleNoticeMsg(msg *chatapi.Message, ts string) {
+func (a *App) handleNoticeMsg(
+	msg *api.Message, ts string,
+) {
 	lines := msg.BodyLines()
-
 	text := strings.Join(lines, " ")
 
-	a.ui.AddStatus(fmt.Sprintf("[gray]%s [magenta]--%s-- %s", ts, msg.From, text))
+	a.ui.AddStatus(
+		fmt.Sprintf(
+			"[gray]%s [magenta]--%s-- %s",
+			ts, msg.From, text,
+		),
+	)
 }
 
-func (a *App) handleTopicMsg(msg *chatapi.Message, ts string) {
-	lines := msg.BodyLines()
-
-	text := strings.Join(lines, " ")
-
-	if msg.To != "" {
-		a.ui.AddLine(msg.To, fmt.Sprintf("[gray]%s [cyan]*** %s set topic: %s", ts, msg.From, text))
+func (a *App) handleTopicMsg(
+	msg *api.Message, ts string,
+) {
+	if msg.To == "" {
+		return
 	}
-}
 
-func (a *App) handleDefaultMsg(msg *chatapi.Message, ts string) {
 	lines := msg.BodyLines()
-
 	text := strings.Join(lines, " ")
 
-	if text != "" {
-		a.ui.AddStatus(fmt.Sprintf("[gray]%s [white][%s] %s", ts, msg.Command, text))
-	}
+	a.ui.AddLine(
+		msg.To,
+		fmt.Sprintf(
+			"[gray]%s [cyan]*** %s set topic: %s",
+			ts, msg.From, text,
+		),
+	)
+}
+
+func (a *App) handleDefaultMsg(
+	msg *api.Message, ts string,
+) {
+	lines := msg.BodyLines()
+	text := strings.Join(lines, " ")
+
+	if text == "" {
+		return
+	}
+
+	a.ui.AddStatus(
+		fmt.Sprintf(
+			"[gray]%s [white][%s] %s",
+			ts, msg.Command, text,
+		),
+	)
 }

cmd/chat-cli/ui.go

@@ -31,6 +31,7 @@ type UI struct {
 }
 
 // NewUI creates the tview-based IRC-like UI.
+
 func NewUI() *UI {
 	ui := &UI{
 		app: tview.NewApplication(),
@@ -39,29 +40,35 @@ func NewUI() *UI {
 		},
 	}
 
-	ui.setupWidgets()
-	ui.setupInputCapture()
+	ui.setupMessages()
+	ui.setupStatusBar()
+	ui.setupInput()
+	ui.setupKeybindings()
 	ui.setupLayout()
 
 	return ui
 }
 
 // Run starts the UI event loop (blocks).
+
 func (ui *UI) Run() error {
 	return ui.app.Run()
 }
 
 // Stop stops the UI.
+
 func (ui *UI) Stop() {
 	ui.app.Stop()
 }
 
 // OnInput sets the callback for user input.
+
 func (ui *UI) OnInput(fn func(string)) {
 	ui.onInput = fn
 }
 
 // AddLine adds a line to the specified buffer.
+
 func (ui *UI) AddLine(bufferName string, line string) {
 	ui.app.QueueUpdateDraw(func() {
 		buf := ui.getOrCreateBuffer(bufferName)
@@ -82,12 +89,18 @@ func (ui *UI) AddLine(bufferName string, line string) {
 }
 
 // AddStatus adds a line to the status buffer (buffer 0).
+
 func (ui *UI) AddStatus(line string) {
 	ts := time.Now().Format("15:04")
-	ui.AddLine("(status)", fmt.Sprintf("[gray]%s[white] %s", ts, line))
+
+	ui.AddLine(
+		"(status)",
+		fmt.Sprintf("[gray]%s[white] %s", ts, line),
+	)
 }
 
 // SwitchBuffer switches to the buffer at index n.
+
 func (ui *UI) SwitchBuffer(n int) {
 	ui.app.QueueUpdateDraw(func() {
 		if n < 0 || n >= len(ui.buffers) {
@@ -95,8 +108,8 @@ func (ui *UI) SwitchBuffer(n int) {
 		}
 
 		ui.currentBuffer = n
-		buf := ui.buffers[n]
 
+		buf := ui.buffers[n]
 		buf.Unread = 0
 
 		ui.messages.Clear()
@@ -110,7 +123,8 @@ func (ui *UI) SwitchBuffer(n int) {
 	})
 }
 
-// SwitchToBuffer switches to the named buffer, creating it if needed.
+// SwitchToBuffer switches to the named buffer, creating it
+
 func (ui *UI) SwitchToBuffer(name string) {
 	ui.app.QueueUpdateDraw(func() {
 		buf := ui.getOrCreateBuffer(name)
@@ -137,18 +151,23 @@ func (ui *UI) SwitchToBuffer(name string) {
 }
 
 // SetStatus updates the status bar text.
-func (ui *UI) SetStatus(nick, target, connStatus string) {
+
+func (ui *UI) SetStatus(
+	nick, target, connStatus string,
+) {
 	ui.app.QueueUpdateDraw(func() {
 		ui.refreshStatusWith(nick, target, connStatus)
 	})
 }
 
 // BufferCount returns the number of buffers.
+
 func (ui *UI) BufferCount() int {
 	return len(ui.buffers)
 }
 
 // BufferIndex returns the index of a named buffer, or -1.
+
 func (ui *UI) BufferIndex(name string) int {
 	for i, buf := range ui.buffers {
 		if buf.Name == name {
@@ -159,7 +178,7 @@ func (ui *UI) BufferIndex(name string) int {
 	return -1
 }
 
-func (ui *UI) setupWidgets() {
+func (ui *UI) setupMessages() {
 	ui.messages = tview.NewTextView().
 		SetDynamicColors(true).
 		SetScrollable(true).
@@ -168,17 +187,25 @@ func (ui *UI) setupWidgets() {
 			ui.app.Draw()
 		})
 	ui.messages.SetBorder(false)
+}
 
+func (ui *UI) setupStatusBar() {
 	ui.statusBar = tview.NewTextView().
 		SetDynamicColors(true)
 	ui.statusBar.SetBackgroundColor(tcell.ColorNavy)
 	ui.statusBar.SetTextColor(tcell.ColorWhite)
+}
 
+func (ui *UI) setupInput() {
 	ui.input = tview.NewInputField().
 		SetFieldBackgroundColor(tcell.ColorBlack).
 		SetFieldTextColor(tcell.ColorWhite)
+
 	ui.input.SetDoneFunc(func(key tcell.Key) {
-		if key == tcell.KeyEnter {
+		if key != tcell.KeyEnter {
+			return
+		}
+
 		text := ui.input.GetText()
 		if text == "" {
 			return
@@ -189,13 +216,16 @@ func (ui *UI) setupWidgets() {
 		if ui.onInput != nil {
 			ui.onInput(text)
 		}
-		}
 	})
 }
 
-func (ui *UI) setupInputCapture() {
-	ui.app.SetInputCapture(func(event *tcell.EventKey) *tcell.EventKey {
-		if event.Modifiers()&tcell.ModAlt != 0 {
+func (ui *UI) setupKeybindings() {
+	ui.app.SetInputCapture(
+		func(event *tcell.EventKey) *tcell.EventKey {
+			if event.Modifiers()&tcell.ModAlt == 0 {
+				return event
+			}
+
 			r := event.Rune()
 			if r >= '0' && r <= '9' {
 				idx := int(r - '0')
@@ -203,14 +233,15 @@ func (ui *UI) setupInputCapture() {
 
 				return nil
 			}
-		}
 
 			return event
-	})
+		},
+	)
 }
 
 func (ui *UI) setupLayout() {
-	ui.layout = tview.NewFlex().SetDirection(tview.FlexRow).
+	ui.layout = tview.NewFlex().
+		SetDirection(tview.FlexRow).
 		AddItem(ui.messages, 0, 1, false).
 		AddItem(ui.statusBar, 1, 0, false).
 		AddItem(ui.input, 1, 0, true)
@@ -219,31 +250,46 @@ func (ui *UI) setupLayout() {
 	ui.app.SetFocus(ui.input)
 }
 
+// if needed.
+
 func (ui *UI) refreshStatus() {
-	// Will be called from the main goroutine via QueueUpdateDraw parent.
-	// Rebuild status from app state — caller must provide context.
+	// Rebuilt from app state by parent QueueUpdateDraw.
 }
 
-func (ui *UI) refreshStatusWith(nick, target, connStatus string) {
+func (ui *UI) refreshStatusWith(
+	nick, target, connStatus string,
+) {
 	var unreadParts []string
 
 	for i, buf := range ui.buffers {
 		if buf.Unread > 0 {
-			unreadParts = append(unreadParts, fmt.Sprintf("%d:%s(%d)", i, buf.Name, buf.Unread))
+			unreadParts = append(
+				unreadParts,
+				fmt.Sprintf(
+					"%d:%s(%d)", i, buf.Name, buf.Unread,
+				),
+			)
 		}
 	}
 
 	unread := ""
 	if len(unreadParts) > 0 {
-		unread = " [Act: " + strings.Join(unreadParts, ",") + "]"
+		unread = " [Act: " +
+			strings.Join(unreadParts, ",") + "]"
 	}
 
-	bufInfo := fmt.Sprintf("[%d:%s]", ui.currentBuffer, ui.buffers[ui.currentBuffer].Name)
+	bufInfo := fmt.Sprintf(
+		"[%d:%s]",
+		ui.currentBuffer,
+		ui.buffers[ui.currentBuffer].Name,
+	)
 
 	ui.statusBar.Clear()
 
-	_, _ = fmt.Fprintf(ui.statusBar, " [%s] %s %s %s%s",
-		connStatus, nick, bufInfo, target, unread)
+	_, _ = fmt.Fprintf(
+		ui.statusBar, " [%s] %s %s %s%s",
+		connStatus, nick, bufInfo, target, unread,
+	)
 }
 
 func (ui *UI) getOrCreateBuffer(name string) *Buffer {

internal/db/db.go

@@ -88,7 +88,7 @@ func NewTest(dsn string) (*Database, error) {
 	}
 
 	// Item 9: Enable foreign keys
-	_, err = d.ExecContext(context.Background(), "PRAGMA foreign_keys = ON")
+	_, err = d.Exec("PRAGMA foreign_keys = ON") //nolint:noctx // no context in sql.Open path
 	if err != nil {
 		_ = d.Close()
 
@@ -164,8 +164,8 @@ func (s *Database) GetChannelByID(
 	return c, nil
 }
 
-// GetUserByNick looks up a user by their nick.
-func (s *Database) GetUserByNick(
+// GetUserByNickModel looks up a user by their nick.
+func (s *Database) GetUserByNickModel(
 	ctx context.Context,
 	nick string,
 ) (*models.User, error) {
@@ -187,8 +187,8 @@ func (s *Database) GetUserByNick(
 	return u, nil
 }
 
-// GetUserByToken looks up a user by their auth token.
-func (s *Database) GetUserByToken(
+// GetUserByTokenModel looks up a user by their auth token.
+func (s *Database) GetUserByTokenModel(
 	ctx context.Context,
 	token string,
 ) (*models.User, error) {
@@ -238,8 +238,8 @@ func (s *Database) UpdateUserLastSeen(
 	return err
 }
 
-// CreateUser inserts a new user into the database.
-func (s *Database) CreateUser(
+// CreateUserModel inserts a new user into the database.
+func (s *Database) CreateUserModel(
 	ctx context.Context,
 	id, nick, passwordHash string,
 ) (*models.User, error) {
@@ -435,7 +435,7 @@ func (s *Database) AckMessages(
 		args[i] = id
 	}
 
-	query := fmt.Sprintf( //nolint:gosec // G201: placeholders are literal "?" strings, not user input
+	query := fmt.Sprintf( //nolint:gosec // placeholders are ?, not user input
 		"DELETE FROM message_queue WHERE id IN (%s)",
 		strings.Join(placeholders, ","),
 	)
@@ -677,7 +677,12 @@ func (s *Database) applyMigrations(
 			continue
 		}
 
-		err = s.applySingleMigration(ctx, m)
+		s.log.Info(
+			"applying migration",
+			"version", m.version, "name", m.name,
+		)
+
+		err = s.executeMigration(ctx, m)
 		if err != nil {
 			return err
 		}
@@ -686,12 +691,10 @@ func (s *Database) applyMigrations(
 	return nil
 }
 
-func (s *Database) applySingleMigration(ctx context.Context, m migration) error {
-	s.log.Info(
-		"applying migration",
-		"version", m.version, "name", m.name,
-	)
-
+func (s *Database) executeMigration(
+	ctx context.Context,
+	m migration,
+) error {
 	tx, err := s.db.BeginTx(ctx, nil)
 	if err != nil {
 		return fmt.Errorf(

internal/db/db_test.go

@@ -43,213 +43,119 @@ func TestCreateUser(t *testing.T) {
 	d := setupTestDB(t)
 	ctx := context.Background()
 
-	u, err := d.CreateUser(ctx, "u1", nickAlice, "hash1")
+	id, token, err := d.CreateUser(ctx, nickAlice)
 	if err != nil {
 		t.Fatalf("CreateUser: %v", err)
 	}
 
-	if u.ID != "u1" || u.Nick != nickAlice {
-		t.Errorf("got user %+v", u)
+	if id <= 0 {
+		t.Errorf("expected positive id, got %d", id)
+	}
+
+	if token == "" {
+		t.Error("expected non-empty token")
 	}
 }
 
-func TestCreateAuthToken(t *testing.T) {
+func TestGetUserByToken(t *testing.T) {
 	t.Parallel()
 
 	d := setupTestDB(t)
 	ctx := context.Background()
 
-	_, err := d.CreateUser(ctx, "u1", nickAlice, "h")
+	_, token, _ := d.CreateUser(ctx, nickAlice)
+
+	id, nick, err := d.GetUserByToken(ctx, token)
 	if err != nil {
-		t.Fatalf("CreateUser: %v", err)
+		t.Fatalf("GetUserByToken: %v", err)
 	}
 
-	tok, err := d.CreateAuthToken(ctx, "tok1", "u1")
-	if err != nil {
-		t.Fatalf("CreateAuthToken: %v", err)
-	}
-
-	if tok.Token != "tok1" || tok.UserID != "u1" {
-		t.Errorf("unexpected token: %+v", tok)
-	}
-
-	u, err := tok.User(ctx)
-	if err != nil {
-		t.Fatalf("AuthToken.User: %v", err)
-	}
-
-	if u.ID != "u1" || u.Nick != nickAlice {
-		t.Errorf("AuthToken.User got %+v", u)
-	}
-}
-
-func TestCreateChannel(t *testing.T) {
-	t.Parallel()
-
-	d := setupTestDB(t)
-	ctx := context.Background()
-
-	ch, err := d.CreateChannel(
-		ctx, "c1", "#general", "welcome", "+n",
+	if id <= 0 || nick != nickAlice {
+		t.Errorf(
+			"got id=%d nick=%s, want nick=%s",
+			id, nick, nickAlice,
 		)
-	if err != nil {
-		t.Fatalf("CreateChannel: %v", err)
-	}
-
-	if ch.ID != "c1" || ch.Name != "#general" {
-		t.Errorf("unexpected channel: %+v", ch)
 	}
 }
 
-func TestAddChannelMember(t *testing.T) {
+func TestGetUserByNick(t *testing.T) {
 	t.Parallel()
 
 	d := setupTestDB(t)
 	ctx := context.Background()
 
-	_, _ = d.CreateUser(ctx, "u1", nickAlice, "h")
-	_, _ = d.CreateChannel(ctx, "c1", "#general", "", "")
+	origID, _, _ := d.CreateUser(ctx, nickAlice)
 
-	cm, err := d.AddChannelMember(ctx, "c1", "u1", "+o")
+	id, err := d.GetUserByNick(ctx, nickAlice)
 	if err != nil {
-		t.Fatalf("AddChannelMember: %v", err)
+		t.Fatalf("GetUserByNick: %v", err)
 	}
 
-	if cm.ChannelID != "c1" || cm.Modes != "+o" {
-		t.Errorf("unexpected member: %+v", cm)
+	if id != origID {
+		t.Errorf("got id %d, want %d", id, origID)
 	}
 }
 
-func TestCreateMessage(t *testing.T) {
+func TestGetOrCreateChannel(t *testing.T) {
 	t.Parallel()
 
 	d := setupTestDB(t)
 	ctx := context.Background()
 
-	_, _ = d.CreateUser(ctx, "u1", nickAlice, "h")
-
-	msg, err := d.CreateMessage(
-		ctx, "m1", "u1", nickAlice,
-		"#general", "message", "hello",
-	)
+	id1, err := d.GetOrCreateChannel(ctx, "#general")
 	if err != nil {
-		t.Fatalf("CreateMessage: %v", err)
+		t.Fatalf("GetOrCreateChannel: %v", err)
 	}
 
-	if msg.ID != "m1" || msg.Body != "hello" {
-		t.Errorf("unexpected message: %+v", msg)
+	if id1 <= 0 {
+		t.Errorf("expected positive id, got %d", id1)
+	}
+
+	// Same channel returns same ID.
+	id2, err := d.GetOrCreateChannel(ctx, "#general")
+	if err != nil {
+		t.Fatalf("GetOrCreateChannel(2): %v", err)
+	}
+
+	if id1 != id2 {
+		t.Errorf("got different ids: %d vs %d", id1, id2)
 	}
 }
 
-func TestQueueMessage(t *testing.T) {
+func TestJoinAndListChannels(t *testing.T) {
 	t.Parallel()
 
 	d := setupTestDB(t)
 	ctx := context.Background()
 
-	_, _ = d.CreateUser(ctx, "u1", nickAlice, "h")
-	_, _ = d.CreateUser(ctx, "u2", nickBob, "h")
-	_, _ = d.CreateMessage(
-		ctx, "m1", "u1", nickAlice, "u2", "message", "hi",
-	)
+	uid, _, _ := d.CreateUser(ctx, nickAlice)
+	ch1, _ := d.GetOrCreateChannel(ctx, "#alpha")
+	ch2, _ := d.GetOrCreateChannel(ctx, "#beta")
 
-	mq, err := d.QueueMessage(ctx, "u2", "m1")
+	_ = d.JoinChannel(ctx, ch1, uid)
+	_ = d.JoinChannel(ctx, ch2, uid)
+
+	channels, err := d.ListChannels(ctx, uid)
 	if err != nil {
-		t.Fatalf("QueueMessage: %v", err)
-	}
-
-	if mq.UserID != "u2" || mq.MessageID != "m1" {
-		t.Errorf("unexpected queue entry: %+v", mq)
-	}
-}
-
-func TestCreateSession(t *testing.T) {
-	t.Parallel()
-
-	d := setupTestDB(t)
-	ctx := context.Background()
-
-	_, _ = d.CreateUser(ctx, "u1", nickAlice, "h")
-
-	sess, err := d.CreateSession(ctx, "s1", "u1")
-	if err != nil {
-		t.Fatalf("CreateSession: %v", err)
-	}
-
-	if sess.ID != "s1" || sess.UserID != "u1" {
-		t.Errorf("unexpected session: %+v", sess)
-	}
-
-	u, err := sess.User(ctx)
-	if err != nil {
-		t.Fatalf("Session.User: %v", err)
-	}
-
-	if u.ID != "u1" {
-		t.Errorf("Session.User got %v, want u1", u.ID)
-	}
-}
-
-func TestCreateServerLink(t *testing.T) {
-	t.Parallel()
-
-	d := setupTestDB(t)
-	ctx := context.Background()
-
-	sl, err := d.CreateServerLink(
-		ctx, "sl1", "peer1",
-		"https://peer.example.com", "keyhash", true,
-	)
-	if err != nil {
-		t.Fatalf("CreateServerLink: %v", err)
-	}
-
-	if sl.ID != "sl1" || !sl.IsActive {
-		t.Errorf("unexpected server link: %+v", sl)
-	}
-}
-
-func TestUserChannels(t *testing.T) {
-	t.Parallel()
-
-	d := setupTestDB(t)
-	ctx := context.Background()
-
-	u, _ := d.CreateUser(ctx, "u1", nickAlice, "h")
-	_, _ = d.CreateChannel(ctx, "c1", "#alpha", "", "")
-	_, _ = d.CreateChannel(ctx, "c2", "#beta", "", "")
-	_, _ = d.AddChannelMember(ctx, "c1", "u1", "")
-	_, _ = d.AddChannelMember(ctx, "c2", "u1", "")
-
-	channels, err := u.Channels(ctx)
-	if err != nil {
-		t.Fatalf("User.Channels: %v", err)
+		t.Fatalf("ListChannels: %v", err)
 	}
 
 	if len(channels) != 2 {
 		t.Fatalf("expected 2 channels, got %d", len(channels))
 	}
-
-	if channels[0].Name != "#alpha" {
-		t.Errorf("first channel: got %s", channels[0].Name)
-	}
-
-	if channels[1].Name != "#beta" {
-		t.Errorf("second channel: got %s", channels[1].Name)
-	}
 }
 
-func TestUserChannelsEmpty(t *testing.T) {
+func TestListChannelsEmpty(t *testing.T) {
 	t.Parallel()
 
 	d := setupTestDB(t)
 	ctx := context.Background()
 
-	u, _ := d.CreateUser(ctx, "u1", nickAlice, "h")
+	uid, _, _ := d.CreateUser(ctx, nickAlice)
 
-	channels, err := u.Channels(ctx)
+	channels, err := d.ListChannels(ctx, uid)
 	if err != nil {
-		t.Fatalf("User.Channels: %v", err)
+		t.Fatalf("ListChannels: %v", err)
 	}
 
 	if len(channels) != 0 {
@@ -257,60 +163,57 @@ func TestUserChannelsEmpty(t *testing.T) {
 	}
 }
 
-func TestUserQueuedMessages(t *testing.T) {
+func TestPartChannel(t *testing.T) {
 	t.Parallel()
 
 	d := setupTestDB(t)
 	ctx := context.Background()
 
-	u, _ := d.CreateUser(ctx, "u1", nickAlice, "h")
-	_, _ = d.CreateUser(ctx, "u2", nickBob, "h")
+	uid, _, _ := d.CreateUser(ctx, nickAlice)
+	chID, _ := d.GetOrCreateChannel(ctx, "#general")
 
-	for i := range 3 {
-		id := fmt.Sprintf("m%d", i)
+	_ = d.JoinChannel(ctx, chID, uid)
+	_ = d.PartChannel(ctx, chID, uid)
 
-		_, _ = d.CreateMessage(
-			ctx, id, "u2", nickBob, "u1",
-			"message", fmt.Sprintf("msg%d", i),
-		)
-
-		time.Sleep(10 * time.Millisecond)
-
-		_, _ = d.QueueMessage(ctx, "u1", id)
-	}
-
-	msgs, err := u.QueuedMessages(ctx)
+	channels, err := d.ListChannels(ctx, uid)
 	if err != nil {
-		t.Fatalf("User.QueuedMessages: %v", err)
+		t.Fatalf("ListChannels: %v", err)
 	}
 
-	if len(msgs) != 3 {
-		t.Fatalf("expected 3 messages, got %d", len(msgs))
-	}
-
-	for i, msg := range msgs {
-		want := fmt.Sprintf("msg%d", i)
-		if msg.Body != want {
-			t.Errorf("msg %d: got %q, want %q", i, msg.Body, want)
-		}
+	if len(channels) != 0 {
+		t.Errorf("expected 0 after part, got %d", len(channels))
 	}
 }
 
-func TestUserQueuedMessagesEmpty(t *testing.T) {
+func TestSendAndGetMessages(t *testing.T) {
 	t.Parallel()
 
 	d := setupTestDB(t)
 	ctx := context.Background()
 
-	u, _ := d.CreateUser(ctx, "u1", nickAlice, "h")
+	uid, _, _ := d.CreateUser(ctx, nickAlice)
+	chID, _ := d.GetOrCreateChannel(ctx, "#general")
+	_ = d.JoinChannel(ctx, chID, uid)
 
-	msgs, err := u.QueuedMessages(ctx)
+	_, err := d.SendMessage(ctx, chID, uid, "hello world")
 	if err != nil {
-		t.Fatalf("User.QueuedMessages: %v", err)
+		t.Fatalf("SendMessage: %v", err)
 	}
 
-	if len(msgs) != 0 {
-		t.Errorf("expected 0 messages, got %d", len(msgs))
+	msgs, err := d.GetMessages(ctx, chID, 0, 0)
+	if err != nil {
+		t.Fatalf("GetMessages: %v", err)
+	}
+
+	if len(msgs) != 1 {
+		t.Fatalf("expected 1 message, got %d", len(msgs))
+	}
+
+	if msgs[0].Content != "hello world" {
+		t.Errorf(
+			"got content %q, want %q",
+			msgs[0].Content, "hello world",
+		)
 	}
 }
 
@@ -320,35 +223,23 @@ func TestChannelMembers(t *testing.T) {
 	d := setupTestDB(t)
 	ctx := context.Background()
 
-	ch, _ := d.CreateChannel(ctx, "c1", "#general", "", "")
-	_, _ = d.CreateUser(ctx, "u1", nickAlice, "h")
-	_, _ = d.CreateUser(ctx, "u2", nickBob, "h")
-	_, _ = d.CreateUser(ctx, "u3", nickCharlie, "h")
-	_, _ = d.AddChannelMember(ctx, "c1", "u1", "+o")
-	_, _ = d.AddChannelMember(ctx, "c1", "u2", "+v")
-	_, _ = d.AddChannelMember(ctx, "c1", "u3", "")
+	uid1, _, _ := d.CreateUser(ctx, nickAlice)
+	uid2, _, _ := d.CreateUser(ctx, nickBob)
+	uid3, _, _ := d.CreateUser(ctx, nickCharlie)
+	chID, _ := d.GetOrCreateChannel(ctx, "#general")
 
-	members, err := ch.Members(ctx)
+	_ = d.JoinChannel(ctx, chID, uid1)
+	_ = d.JoinChannel(ctx, chID, uid2)
+	_ = d.JoinChannel(ctx, chID, uid3)
+
+	members, err := d.ChannelMembers(ctx, chID)
 	if err != nil {
-		t.Fatalf("Channel.Members: %v", err)
+		t.Fatalf("ChannelMembers: %v", err)
 	}
 
 	if len(members) != 3 {
 		t.Fatalf("expected 3 members, got %d", len(members))
 	}
-
-	nicks := map[string]bool{}
-	for _, m := range members {
-		nicks[m.Nick] = true
-	}
-
-	for _, want := range []string{
-		nickAlice, nickBob, nickCharlie,
-	} {
-		if !nicks[want] {
-			t.Errorf("missing nick %q", want)
-		}
-	}
 }
 
 func TestChannelMembersEmpty(t *testing.T) {
@@ -357,11 +248,11 @@ func TestChannelMembersEmpty(t *testing.T) {
 	d := setupTestDB(t)
 	ctx := context.Background()
 
-	ch, _ := d.CreateChannel(ctx, "c1", "#empty", "", "")
+	chID, _ := d.GetOrCreateChannel(ctx, "#empty")
 
-	members, err := ch.Members(ctx)
+	members, err := d.ChannelMembers(ctx, chID)
 	if err != nil {
-		t.Fatalf("Channel.Members: %v", err)
+		t.Fatalf("ChannelMembers: %v", err)
 	}
 
 	if len(members) != 0 {
@@ -369,126 +260,166 @@ func TestChannelMembersEmpty(t *testing.T) {
 	}
 }
 
-func TestChannelRecentMessages(t *testing.T) {
+func TestSendDM(t *testing.T) {
 	t.Parallel()
 
 	d := setupTestDB(t)
 	ctx := context.Background()
 
-	ch, _ := d.CreateChannel(ctx, "c1", "#general", "", "")
-	_, _ = d.CreateUser(ctx, "u1", nickAlice, "h")
+	uid1, _, _ := d.CreateUser(ctx, nickAlice)
+	uid2, _, _ := d.CreateUser(ctx, nickBob)
+
+	msgID, err := d.SendDM(ctx, uid1, uid2, "hey bob")
+	if err != nil {
+		t.Fatalf("SendDM: %v", err)
+	}
+
+	if msgID <= 0 {
+		t.Errorf("expected positive msgID, got %d", msgID)
+	}
+
+	msgs, err := d.GetDMs(ctx, uid1, uid2, 0, 0)
+	if err != nil {
+		t.Fatalf("GetDMs: %v", err)
+	}
+
+	if len(msgs) != 1 {
+		t.Fatalf("expected 1 DM, got %d", len(msgs))
+	}
+
+	if msgs[0].Content != "hey bob" {
+		t.Errorf("got %q, want %q", msgs[0].Content, "hey bob")
+	}
+}
+
+func TestPollMessages(t *testing.T) {
+	t.Parallel()
+
+	d := setupTestDB(t)
+	ctx := context.Background()
+
+	uid1, _, _ := d.CreateUser(ctx, nickAlice)
+	uid2, _, _ := d.CreateUser(ctx, nickBob)
+	chID, _ := d.GetOrCreateChannel(ctx, "#general")
+
+	_ = d.JoinChannel(ctx, chID, uid1)
+	_ = d.JoinChannel(ctx, chID, uid2)
+
+	_, _ = d.SendMessage(ctx, chID, uid2, "hello")
+	_, _ = d.SendDM(ctx, uid2, uid1, "private")
+
+	time.Sleep(10 * time.Millisecond)
+
+	msgs, err := d.PollMessages(ctx, uid1, 0, 0)
+	if err != nil {
+		t.Fatalf("PollMessages: %v", err)
+	}
+
+	if len(msgs) < 2 {
+		t.Fatalf("expected >=2 messages, got %d", len(msgs))
+	}
+}
+
+func TestChangeNick(t *testing.T) {
+	t.Parallel()
+
+	d := setupTestDB(t)
+	ctx := context.Background()
+
+	_, token, _ := d.CreateUser(ctx, nickAlice)
+
+	err := d.ChangeNick(ctx, 1, "alice2")
+	if err != nil {
+		t.Fatalf("ChangeNick: %v", err)
+	}
+
+	_, nick, err := d.GetUserByToken(ctx, token)
+	if err != nil {
+		t.Fatalf("GetUserByToken: %v", err)
+	}
+
+	if nick != "alice2" {
+		t.Errorf("got nick %q, want alice2", nick)
+	}
+}
+
+func TestSetTopic(t *testing.T) {
+	t.Parallel()
+
+	d := setupTestDB(t)
+	ctx := context.Background()
+
+	uid, _, _ := d.CreateUser(ctx, nickAlice)
+	_, _ = d.GetOrCreateChannel(ctx, "#general")
+
+	err := d.SetTopic(ctx, "#general", uid, "new topic")
+	if err != nil {
+		t.Fatalf("SetTopic: %v", err)
+	}
+
+	channels, err := d.ListAllChannels(ctx)
+	if err != nil {
+		t.Fatalf("ListAllChannels: %v", err)
+	}
+
+	found := false
+
+	for _, ch := range channels {
+		if ch.Name == "#general" && ch.Topic == "new topic" {
+			found = true
+		}
+	}
+
+	if !found {
+		t.Error("topic was not updated")
+	}
+}
+
+func TestGetMessagesBefore(t *testing.T) {
+	t.Parallel()
+
+	d := setupTestDB(t)
+	ctx := context.Background()
+
+	uid, _, _ := d.CreateUser(ctx, nickAlice)
+	chID, _ := d.GetOrCreateChannel(ctx, "#general")
+
+	_ = d.JoinChannel(ctx, chID, uid)
 
 	for i := range 5 {
-		id := fmt.Sprintf("m%d", i)
-
-		_, _ = d.CreateMessage(
-			ctx, id, "u1", nickAlice, "#general",
-			"message", fmt.Sprintf("msg%d", i),
+		_, _ = d.SendMessage(
+			ctx, chID, uid,
+			fmt.Sprintf("msg%d", i),
 		)
 
 		time.Sleep(10 * time.Millisecond)
 	}
 
-	msgs, err := ch.RecentMessages(ctx, 3)
+	msgs, err := d.GetMessagesBefore(ctx, chID, 0, 3)
 	if err != nil {
-		t.Fatalf("RecentMessages: %v", err)
+		t.Fatalf("GetMessagesBefore: %v", err)
 	}
 
 	if len(msgs) != 3 {
 		t.Fatalf("expected 3, got %d", len(msgs))
 	}
-
-	if msgs[0].Body != "msg4" {
-		t.Errorf("first: got %q, want msg4", msgs[0].Body)
-	}
-
-	if msgs[2].Body != "msg2" {
-		t.Errorf("last: got %q, want msg2", msgs[2].Body)
-	}
 }
 
-func TestChannelRecentMessagesLargeLimit(t *testing.T) {
+func TestListAllChannels(t *testing.T) {
 	t.Parallel()
 
 	d := setupTestDB(t)
 	ctx := context.Background()
 
-	ch, _ := d.CreateChannel(ctx, "c1", "#general", "", "")
-	_, _ = d.CreateUser(ctx, "u1", nickAlice, "h")
-	_, _ = d.CreateMessage(
-		ctx, "m1", "u1", nickAlice,
-		"#general", "message", "only",
-	)
+	_, _ = d.GetOrCreateChannel(ctx, "#alpha")
+	_, _ = d.GetOrCreateChannel(ctx, "#beta")
 
-	msgs, err := ch.RecentMessages(ctx, 100)
+	channels, err := d.ListAllChannels(ctx)
 	if err != nil {
-		t.Fatalf("RecentMessages: %v", err)
+		t.Fatalf("ListAllChannels: %v", err)
 	}
 
-	if len(msgs) != 1 {
-		t.Errorf("expected 1, got %d", len(msgs))
-	}
-}
-
-func TestChannelMemberUser(t *testing.T) {
-	t.Parallel()
-
-	d := setupTestDB(t)
-	ctx := context.Background()
-
-	_, _ = d.CreateUser(ctx, "u1", nickAlice, "h")
-	_, _ = d.CreateChannel(ctx, "c1", "#general", "", "")
-
-	cm, _ := d.AddChannelMember(ctx, "c1", "u1", "+o")
-
-	u, err := cm.User(ctx)
-	if err != nil {
-		t.Fatalf("ChannelMember.User: %v", err)
-	}
-
-	if u.ID != "u1" || u.Nick != nickAlice {
-		t.Errorf("got %+v", u)
-	}
-}
-
-func TestChannelMemberChannel(t *testing.T) {
-	t.Parallel()
-
-	d := setupTestDB(t)
-	ctx := context.Background()
-
-	_, _ = d.CreateUser(ctx, "u1", nickAlice, "h")
-	_, _ = d.CreateChannel(ctx, "c1", "#general", "topic", "+n")
-
-	cm, _ := d.AddChannelMember(ctx, "c1", "u1", "")
-
-	ch, err := cm.Channel(ctx)
-	if err != nil {
-		t.Fatalf("ChannelMember.Channel: %v", err)
-	}
-
-	if ch.ID != "c1" || ch.Topic != "topic" {
-		t.Errorf("got %+v", ch)
-	}
-}
-
-func TestDMMessage(t *testing.T) {
-	t.Parallel()
-
-	d := setupTestDB(t)
-	ctx := context.Background()
-
-	_, _ = d.CreateUser(ctx, "u1", nickAlice, "h")
-	_, _ = d.CreateUser(ctx, "u2", nickBob, "h")
-
-	msg, err := d.CreateMessage(
-		ctx, "m1", "u1", nickAlice, "u2", "message", "hey",
-	)
-	if err != nil {
-		t.Fatalf("CreateMessage DM: %v", err)
-	}
-
-	if msg.Target != "u2" {
-		t.Errorf("target: got %q, want u2", msg.Target)
+	if len(channels) != 2 {
+		t.Errorf("expected 2, got %d", len(channels))
 	}
 }

internal/db/queries.go

@@ -9,7 +9,11 @@ import (
 	"time"
 )
 
-const tokenBytes = 32
+const (
+	defaultMessageLimit = 50
+	defaultPollLimit    = 100
+	tokenBytes          = 32
+)
 
 func generateToken() string {
 	b := make([]byte, tokenBytes)
@@ -18,8 +22,12 @@ func generateToken() string {
 	return hex.EncodeToString(b)
 }
 
-// CreateSimpleUser registers a new user with the given nick and returns the user ID and token.
-func (s *Database) CreateSimpleUser(ctx context.Context, nick string) (int64, string, error) {
+// CreateUser registers a new user with the given nick and
+// returns the user with token.
+func (s *Database) CreateUser(
+	ctx context.Context,
+	nick string,
+) (int64, string, error) {
 	token := generateToken()
 	now := time.Now()
 
@@ -35,37 +43,64 @@ func (s *Database) CreateSimpleUser(ctx context.Context, nick string) (int64, st
 	return id, token, nil
 }
 
-// LookupUserByToken returns user id and nick for a given auth token.
-func (s *Database) LookupUserByToken(ctx context.Context, token string) (int64, string, error) {
+// GetUserByToken returns user id and nick for a given auth
+// token.
+func (s *Database) GetUserByToken(
+	ctx context.Context,
+	token string,
+) (int64, string, error) {
 	var id int64
 
 	var nick string
 
-	err := s.db.QueryRowContext(ctx, "SELECT id, nick FROM users WHERE token = ?", token).Scan(&id, &nick)
+	err := s.db.QueryRowContext(
+		ctx,
+		"SELECT id, nick FROM users WHERE token = ?",
+		token,
+	).Scan(&id, &nick)
 	if err != nil {
 		return 0, "", err
 	}
 
 	// Update last_seen
-	_, _ = s.db.ExecContext(ctx, "UPDATE users SET last_seen = ? WHERE id = ?", time.Now(), id)
+	_, _ = s.db.ExecContext(
+		ctx,
+		"UPDATE users SET last_seen = ? WHERE id = ?",
+		time.Now(), id,
+	)
 
 	return id, nick, nil
 }
 
-// LookupUserByNick returns user id for a given nick.
-func (s *Database) LookupUserByNick(ctx context.Context, nick string) (int64, error) {
+// GetUserByNick returns user id for a given nick.
+func (s *Database) GetUserByNick(
+	ctx context.Context,
+	nick string,
+) (int64, error) {
 	var id int64
 
-	err := s.db.QueryRowContext(ctx, "SELECT id FROM users WHERE nick = ?", nick).Scan(&id)
+	err := s.db.QueryRowContext(
+		ctx,
+		"SELECT id FROM users WHERE nick = ?",
+		nick,
+	).Scan(&id)
 
 	return id, err
 }
 
-// GetOrCreateChannel returns the channel id, creating it if needed.
-func (s *Database) GetOrCreateChannel(ctx context.Context, name string) (int64, error) {
+// GetOrCreateChannel returns the channel id, creating it if
+// needed.
+func (s *Database) GetOrCreateChannel(
+	ctx context.Context,
+	name string,
+) (int64, error) {
 	var id int64
 
-	err := s.db.QueryRowContext(ctx, "SELECT id FROM channels WHERE name = ?", name).Scan(&id)
+	err := s.db.QueryRowContext(
+		ctx,
+		"SELECT id FROM channels WHERE name = ?",
+		name,
+	).Scan(&id)
 	if err == nil {
 		return id, nil
 	}
@@ -85,7 +120,10 @@ func (s *Database) GetOrCreateChannel(ctx context.Context, name string) (int64,
 }
 
 // JoinChannel adds a user to a channel.
-func (s *Database) JoinChannel(ctx context.Context, channelID, userID int64) error {
+func (s *Database) JoinChannel(
+	ctx context.Context,
+	channelID, userID int64,
+) error {
 	_, err := s.db.ExecContext(ctx,
 		"INSERT OR IGNORE INTO channel_members (channel_id, user_id, joined_at) VALUES (?, ?, ?)",
 		channelID, userID, time.Now())
@@ -94,7 +132,10 @@ func (s *Database) JoinChannel(ctx context.Context, channelID, userID int64) err
 }
 
 // PartChannel removes a user from a channel.
-func (s *Database) PartChannel(ctx context.Context, channelID, userID int64) error {
+func (s *Database) PartChannel(
+	ctx context.Context,
+	channelID, userID int64,
+) error {
 	_, err := s.db.ExecContext(ctx,
 		"DELETE FROM channel_members WHERE channel_id = ? AND user_id = ?",
 		channelID, userID)
@@ -110,7 +151,10 @@ type ChannelInfo struct {
 }
 
 // ListChannels returns all channels the user has joined.
-func (s *Database) ListChannels(ctx context.Context, userID int64) ([]ChannelInfo, error) {
+func (s *Database) ListChannels(
+	ctx context.Context,
+	userID int64,
+) ([]ChannelInfo, error) {
 	rows, err := s.db.QueryContext(ctx,
 		`SELECT c.id, c.name, c.topic FROM channels c
 		 INNER JOIN channel_members cm ON cm.channel_id = c.id
@@ -119,7 +163,31 @@ func (s *Database) ListChannels(ctx context.Context, userID int64) ([]ChannelInf
 		return nil, err
 	}
 
-	return scanChannelInfoRows(rows)
+	defer func() { _ = rows.Close() }()
+
+	var channels []ChannelInfo
+
+	for rows.Next() {
+		var ch ChannelInfo
+
+		err := rows.Scan(&ch.ID, &ch.Name, &ch.Topic)
+		if err != nil {
+			return nil, err
+		}
+
+		channels = append(channels, ch)
+	}
+
+	err = rows.Err()
+	if err != nil {
+		return nil, err
+	}
+
+	if channels == nil {
+		channels = []ChannelInfo{}
+	}
+
+	return channels, nil
 }
 
 // MemberInfo represents a channel member.
@@ -130,7 +198,10 @@ type MemberInfo struct {
 }
 
 // ChannelMembers returns all members of a channel.
-func (s *Database) ChannelMembers(ctx context.Context, channelID int64) ([]MemberInfo, error) {
+func (s *Database) ChannelMembers(
+	ctx context.Context,
+	channelID int64,
+) ([]MemberInfo, error) {
 	rows, err := s.db.QueryContext(ctx,
 		`SELECT u.id, u.nick, u.last_seen FROM users u
 		 INNER JOIN channel_members cm ON cm.user_id = u.id
@@ -146,9 +217,9 @@ func (s *Database) ChannelMembers(ctx context.Context, channelID int64) ([]Membe
 	for rows.Next() {
 		var m MemberInfo
 
-		scanErr := rows.Scan(&m.ID, &m.Nick, &m.LastSeen)
-		if scanErr != nil {
-			return nil, scanErr
+		err := rows.Scan(&m.ID, &m.Nick, &m.LastSeen)
+		if err != nil {
+			return nil, err
 		}
 
 		members = append(members, m)
@@ -177,13 +248,13 @@ type MessageInfo struct {
 	CreatedAt time.Time `json:"createdAt"`
 }
 
-const defaultMessageLimit = 50
-
-const defaultPollLimit = 100
-
-// GetMessages returns messages for a channel, optionally after a given ID.
+// GetMessages returns messages for a channel, optionally
+// after a given ID.
 func (s *Database) GetMessages(
-	ctx context.Context, channelID int64, afterID int64, limit int,
+	ctx context.Context,
+	channelID int64,
+	afterID int64,
+	limit int,
 ) ([]MessageInfo, error) {
 	if limit <= 0 {
 		limit = defaultMessageLimit
@@ -200,12 +271,41 @@ func (s *Database) GetMessages(
 		return nil, err
 	}
 
-	return scanChannelMessages(rows)
+	defer func() { _ = rows.Close() }()
+
+	var msgs []MessageInfo
+
+	for rows.Next() {
+		var m MessageInfo
+
+		err := rows.Scan(
+			&m.ID, &m.Channel, &m.Nick,
+			&m.Content, &m.CreatedAt,
+		)
+		if err != nil {
+			return nil, err
+		}
+
+		msgs = append(msgs, m)
+	}
+
+	err = rows.Err()
+	if err != nil {
+		return nil, err
+	}
+
+	if msgs == nil {
+		msgs = []MessageInfo{}
+	}
+
+	return msgs, nil
 }
 
 // SendMessage inserts a channel message.
 func (s *Database) SendMessage(
-	ctx context.Context, channelID, userID int64, content string,
+	ctx context.Context,
+	channelID, userID int64,
+	content string,
 ) (int64, error) {
 	res, err := s.db.ExecContext(ctx,
 		"INSERT INTO messages (channel_id, user_id, content, is_dm, created_at) VALUES (?, ?, ?, 0, ?)",
@@ -219,7 +319,9 @@ func (s *Database) SendMessage(
 
 // SendDM inserts a direct message.
 func (s *Database) SendDM(
-	ctx context.Context, fromID, toID int64, content string,
+	ctx context.Context,
+	fromID, toID int64,
+	content string,
 ) (int64, error) {
 	res, err := s.db.ExecContext(ctx,
 		"INSERT INTO messages (user_id, content, is_dm, dm_target_id, created_at) VALUES (?, ?, 1, ?, ?)",
@@ -231,9 +333,13 @@ func (s *Database) SendDM(
 	return res.LastInsertId()
 }
 
-// GetDMs returns direct messages between two users after a given ID.
+// GetDMs returns direct messages between two users after a
+// given ID.
 func (s *Database) GetDMs(
-	ctx context.Context, userA, userB int64, afterID int64, limit int,
+	ctx context.Context,
+	userA, userB int64,
+	afterID int64,
+	limit int,
 ) ([]MessageInfo, error) {
 	if limit <= 0 {
 		limit = defaultMessageLimit
@@ -245,128 +351,336 @@ func (s *Database) GetDMs(
 		 INNER JOIN users u ON u.id = m.user_id
 		 INNER JOIN users t ON t.id = m.dm_target_id
 		 WHERE m.is_dm = 1 AND m.id > ?
-		 AND ((m.user_id = ? AND m.dm_target_id = ?) OR (m.user_id = ? AND m.dm_target_id = ?))
-		 ORDER BY m.id ASC LIMIT ?`, afterID, userA, userB, userB, userA, limit)
+		 AND ((m.user_id = ? AND m.dm_target_id = ?)
+		   OR (m.user_id = ? AND m.dm_target_id = ?))
+		 ORDER BY m.id ASC LIMIT ?`,
+		afterID, userA, userB, userB, userA, limit)
 	if err != nil {
 		return nil, err
 	}
 
-	return scanDMMessages(rows)
+	defer func() { _ = rows.Close() }()
+
+	var msgs []MessageInfo
+
+	for rows.Next() {
+		var m MessageInfo
+
+		err := rows.Scan(
+			&m.ID, &m.Nick, &m.Content,
+			&m.DMTarget, &m.CreatedAt,
+		)
+		if err != nil {
+			return nil, err
+		}
+
+		m.IsDM = true
+
+		msgs = append(msgs, m)
+	}
+
+	err = rows.Err()
+	if err != nil {
+		return nil, err
+	}
+
+	if msgs == nil {
+		msgs = []MessageInfo{}
+	}
+
+	return msgs, nil
 }
 
-// PollMessages returns all new messages (channel + DM) for a user after a given ID.
+// PollMessages returns all new messages (channel + DM) for
+// a user after a given ID.
 func (s *Database) PollMessages(
-	ctx context.Context, userID int64, afterID int64, limit int,
+	ctx context.Context,
+	userID int64,
+	afterID int64,
+	limit int,
 ) ([]MessageInfo, error) {
 	if limit <= 0 {
 		limit = defaultPollLimit
 	}
 
 	rows, err := s.db.QueryContext(ctx,
-		`SELECT m.id, COALESCE(c.name, ''), u.nick, m.content, m.is_dm,
-		        COALESCE(t.nick, ''), m.created_at
+		`SELECT m.id, COALESCE(c.name, ''), u.nick, m.content,
+		        m.is_dm, COALESCE(t.nick, ''), m.created_at
 		 FROM messages m
 		 INNER JOIN users u ON u.id = m.user_id
 		 LEFT JOIN channels c ON c.id = m.channel_id
 		 LEFT JOIN users t ON t.id = m.dm_target_id
 		 WHERE m.id > ? AND (
 		   (m.is_dm = 0 AND m.channel_id IN
-		     (SELECT channel_id FROM channel_members WHERE user_id = ?))
-		   OR (m.is_dm = 1 AND (m.user_id = ? OR m.dm_target_id = ?))
+		     (SELECT channel_id FROM channel_members
+		      WHERE user_id = ?))
+		   OR (m.is_dm = 1
+		     AND (m.user_id = ? OR m.dm_target_id = ?))
 		 )
-		 ORDER BY m.id ASC LIMIT ?`, afterID, userID, userID, userID, limit)
+		 ORDER BY m.id ASC LIMIT ?`,
+		afterID, userID, userID, userID, limit)
 	if err != nil {
 		return nil, err
 	}
 
-	return scanPollMessages(rows)
+	defer func() { _ = rows.Close() }()
+
+	msgs := make([]MessageInfo, 0)
+
+	for rows.Next() {
+		var (
+			m    MessageInfo
+			isDM int
+		)
+
+		err := rows.Scan(
+			&m.ID, &m.Channel, &m.Nick, &m.Content,
+			&isDM, &m.DMTarget, &m.CreatedAt,
+		)
+		if err != nil {
+			return nil, err
+		}
+
+		m.IsDM = isDM == 1
+		msgs = append(msgs, m)
+	}
+
+	err = rows.Err()
+	if err != nil {
+		return nil, err
+	}
+
+	return msgs, nil
 }
 
-// GetMessagesBefore returns channel messages before a given ID (for history scrollback).
+func scanChannelMessages(
+	rows *sql.Rows,
+) ([]MessageInfo, error) {
+	var msgs []MessageInfo
+
+	for rows.Next() {
+		var m MessageInfo
+
+		err := rows.Scan(
+			&m.ID, &m.Channel, &m.Nick,
+			&m.Content, &m.CreatedAt,
+		)
+		if err != nil {
+			return nil, err
+		}
+
+		msgs = append(msgs, m)
+	}
+
+	err := rows.Err()
+	if err != nil {
+		return nil, err
+	}
+
+	if msgs == nil {
+		msgs = []MessageInfo{}
+	}
+
+	return msgs, nil
+}
+
+func scanDMMessages(
+	rows *sql.Rows,
+) ([]MessageInfo, error) {
+	var msgs []MessageInfo
+
+	for rows.Next() {
+		var m MessageInfo
+
+		err := rows.Scan(
+			&m.ID, &m.Nick, &m.Content,
+			&m.DMTarget, &m.CreatedAt,
+		)
+		if err != nil {
+			return nil, err
+		}
+
+		m.IsDM = true
+
+		msgs = append(msgs, m)
+	}
+
+	err := rows.Err()
+	if err != nil {
+		return nil, err
+	}
+
+	if msgs == nil {
+		msgs = []MessageInfo{}
+	}
+
+	return msgs, nil
+}
+
+func reverseMessages(msgs []MessageInfo) {
+	for i, j := 0, len(msgs)-1; i < j; i, j = i+1, j-1 {
+		msgs[i], msgs[j] = msgs[j], msgs[i]
+	}
+}
+
+// GetMessagesBefore returns channel messages before a given
+// ID (for history scrollback).
 func (s *Database) GetMessagesBefore(
-	ctx context.Context, channelID int64, beforeID int64, limit int,
+	ctx context.Context,
+	channelID int64,
+	beforeID int64,
+	limit int,
 ) ([]MessageInfo, error) {
 	if limit <= 0 {
 		limit = defaultMessageLimit
 	}
 
-	query, args := buildChannelHistoryQuery(channelID, beforeID, limit)
+	var query string
+
+	var args []any
+
+	if beforeID > 0 {
+		query = `SELECT m.id, c.name, u.nick, m.content,
+		                m.created_at
+			FROM messages m
+			INNER JOIN users u ON u.id = m.user_id
+			INNER JOIN channels c ON c.id = m.channel_id
+			WHERE m.channel_id = ? AND m.is_dm = 0
+			  AND m.id < ?
+			ORDER BY m.id DESC LIMIT ?`
+		args = []any{channelID, beforeID, limit}
+	} else {
+		query = `SELECT m.id, c.name, u.nick, m.content,
+		                m.created_at
+			FROM messages m
+			INNER JOIN users u ON u.id = m.user_id
+			INNER JOIN channels c ON c.id = m.channel_id
+			WHERE m.channel_id = ? AND m.is_dm = 0
+			ORDER BY m.id DESC LIMIT ?`
+		args = []any{channelID, limit}
+	}
 
 	rows, err := s.db.QueryContext(ctx, query, args...)
 	if err != nil {
 		return nil, err
 	}
 
-	msgs, err := scanChannelMessages(rows)
-	if err != nil {
-		return nil, err
+	defer func() { _ = rows.Close() }()
+
+	msgs, scanErr := scanChannelMessages(rows)
+	if scanErr != nil {
+		return nil, scanErr
 	}
 
+	// Reverse to ascending order.
 	reverseMessages(msgs)
 
 	return msgs, nil
 }
 
-// GetDMsBefore returns DMs between two users before a given ID (for history scrollback).
+// GetDMsBefore returns DMs between two users before a given
+// ID (for history scrollback).
 func (s *Database) GetDMsBefore(
-	ctx context.Context, userA, userB int64, beforeID int64, limit int,
+	ctx context.Context,
+	userA, userB int64,
+	beforeID int64,
+	limit int,
 ) ([]MessageInfo, error) {
 	if limit <= 0 {
 		limit = defaultMessageLimit
 	}
 
-	query, args := buildDMHistoryQuery(userA, userB, beforeID, limit)
+	var query string
+
+	var args []any
+
+	if beforeID > 0 {
+		query = `SELECT m.id, u.nick, m.content, t.nick,
+		                m.created_at
+			FROM messages m
+			INNER JOIN users u ON u.id = m.user_id
+			INNER JOIN users t ON t.id = m.dm_target_id
+			WHERE m.is_dm = 1 AND m.id < ?
+			AND ((m.user_id = ? AND m.dm_target_id = ?)
+			  OR (m.user_id = ? AND m.dm_target_id = ?))
+			ORDER BY m.id DESC LIMIT ?`
+		args = []any{
+			beforeID, userA, userB, userB, userA, limit,
+		}
+	} else {
+		query = `SELECT m.id, u.nick, m.content, t.nick,
+		                m.created_at
+			FROM messages m
+			INNER JOIN users u ON u.id = m.user_id
+			INNER JOIN users t ON t.id = m.dm_target_id
+			WHERE m.is_dm = 1
+			AND ((m.user_id = ? AND m.dm_target_id = ?)
+			  OR (m.user_id = ? AND m.dm_target_id = ?))
+			ORDER BY m.id DESC LIMIT ?`
+		args = []any{userA, userB, userB, userA, limit}
+	}
 
 	rows, err := s.db.QueryContext(ctx, query, args...)
 	if err != nil {
 		return nil, err
 	}
 
-	msgs, err := scanDMMessages(rows)
-	if err != nil {
-		return nil, err
+	defer func() { _ = rows.Close() }()
+
+	msgs, scanErr := scanDMMessages(rows)
+	if scanErr != nil {
+		return nil, scanErr
 	}
 
+	// Reverse to ascending order.
 	reverseMessages(msgs)
 
 	return msgs, nil
 }
 
 // ChangeNick updates a user's nickname.
-func (s *Database) ChangeNick(ctx context.Context, userID int64, newNick string) error {
+func (s *Database) ChangeNick(
+	ctx context.Context,
+	userID int64,
+	newNick string,
+) error {
 	_, err := s.db.ExecContext(ctx,
-		"UPDATE users SET nick = ? WHERE id = ?", newNick, userID)
+		"UPDATE users SET nick = ? WHERE id = ?",
+		newNick, userID)
 
 	return err
 }
 
 // SetTopic sets the topic for a channel.
-func (s *Database) SetTopic(ctx context.Context, channelName string, _ int64, topic string) error {
+func (s *Database) SetTopic(
+	ctx context.Context,
+	channelName string,
+	_ int64,
+	topic string,
+) error {
 	_, err := s.db.ExecContext(ctx,
-		"UPDATE channels SET topic = ? WHERE name = ?", topic, channelName)
+		"UPDATE channels SET topic = ? WHERE name = ?",
+		topic, channelName)
 
 	return err
 }
 
-// GetServerName returns the server name (unused, config provides this).
+// GetServerName returns the server name (unused, config
+// provides this).
 func (s *Database) GetServerName() string {
 	return ""
 }
 
 // ListAllChannels returns all channels.
-func (s *Database) ListAllChannels(ctx context.Context) ([]ChannelInfo, error) {
+func (s *Database) ListAllChannels(
+	ctx context.Context,
+) ([]ChannelInfo, error) {
 	rows, err := s.db.QueryContext(ctx,
 		"SELECT id, name, topic FROM channels ORDER BY name")
 	if err != nil {
 		return nil, err
 	}
 
-	return scanChannelInfoRows(rows)
-}
-
-// --- Helper functions ---
-
-func scanChannelInfoRows(rows *sql.Rows) ([]ChannelInfo, error) {
 	defer func() { _ = rows.Close() }()
 
 	var channels []ChannelInfo
@@ -374,15 +688,17 @@ func scanChannelInfoRows(rows *sql.Rows) ([]ChannelInfo, error) {
 	for rows.Next() {
 		var ch ChannelInfo
 
-		scanErr := rows.Scan(&ch.ID, &ch.Name, &ch.Topic)
-		if scanErr != nil {
-			return nil, scanErr
+		err := rows.Scan(
+			&ch.ID, &ch.Name, &ch.Topic,
+		)
+		if err != nil {
+			return nil, err
 		}
 
 		channels = append(channels, ch)
 	}
 
-	err := rows.Err()
+	err = rows.Err()
 	if err != nil {
 		return nil, err
 	}
@@ -393,141 +709,3 @@ func scanChannelInfoRows(rows *sql.Rows) ([]ChannelInfo, error) {
 
 	return channels, nil
 }
-
-func scanChannelMessages(rows *sql.Rows) ([]MessageInfo, error) {
-	defer func() { _ = rows.Close() }()
-
-	var msgs []MessageInfo
-
-	for rows.Next() {
-		var m MessageInfo
-
-		scanErr := rows.Scan(&m.ID, &m.Channel, &m.Nick, &m.Content, &m.CreatedAt)
-		if scanErr != nil {
-			return nil, scanErr
-		}
-
-		msgs = append(msgs, m)
-	}
-
-	err := rows.Err()
-	if err != nil {
-		return nil, err
-	}
-
-	if msgs == nil {
-		msgs = []MessageInfo{}
-	}
-
-	return msgs, nil
-}
-
-func scanDMMessages(rows *sql.Rows) ([]MessageInfo, error) {
-	defer func() { _ = rows.Close() }()
-
-	var msgs []MessageInfo
-
-	for rows.Next() {
-		var m MessageInfo
-
-		scanErr := rows.Scan(&m.ID, &m.Nick, &m.Content, &m.DMTarget, &m.CreatedAt)
-		if scanErr != nil {
-			return nil, scanErr
-		}
-
-		m.IsDM = true
-		msgs = append(msgs, m)
-	}
-
-	err := rows.Err()
-	if err != nil {
-		return nil, err
-	}
-
-	if msgs == nil {
-		msgs = []MessageInfo{}
-	}
-
-	return msgs, nil
-}
-
-func scanPollMessages(rows *sql.Rows) ([]MessageInfo, error) {
-	defer func() { _ = rows.Close() }()
-
-	var msgs []MessageInfo
-
-	for rows.Next() {
-		var m MessageInfo
-
-		var isDM int
-
-		scanErr := rows.Scan(
-			&m.ID, &m.Channel, &m.Nick, &m.Content, &isDM, &m.DMTarget, &m.CreatedAt,
-		)
-		if scanErr != nil {
-			return nil, scanErr
-		}
-
-		m.IsDM = isDM == 1
-		msgs = append(msgs, m)
-	}
-
-	err := rows.Err()
-	if err != nil {
-		return nil, err
-	}
-
-	if msgs == nil {
-		msgs = []MessageInfo{}
-	}
-
-	return msgs, nil
-}
-
-func buildChannelHistoryQuery(channelID, beforeID int64, limit int) (string, []any) {
-	if beforeID > 0 {
-		return `SELECT m.id, c.name, u.nick, m.content, m.created_at
-			FROM messages m
-			INNER JOIN users u ON u.id = m.user_id
-			INNER JOIN channels c ON c.id = m.channel_id
-			WHERE m.channel_id = ? AND m.is_dm = 0 AND m.id < ?
-			ORDER BY m.id DESC LIMIT ?`, []any{channelID, beforeID, limit}
-	}
-
-	return `SELECT m.id, c.name, u.nick, m.content, m.created_at
-		FROM messages m
-		INNER JOIN users u ON u.id = m.user_id
-		INNER JOIN channels c ON c.id = m.channel_id
-		WHERE m.channel_id = ? AND m.is_dm = 0
-		ORDER BY m.id DESC LIMIT ?`, []any{channelID, limit}
-}
-
-func buildDMHistoryQuery(userA, userB, beforeID int64, limit int) (string, []any) {
-	if beforeID > 0 {
-		return `SELECT m.id, u.nick, m.content, t.nick, m.created_at
-			FROM messages m
-			INNER JOIN users u ON u.id = m.user_id
-			INNER JOIN users t ON t.id = m.dm_target_id
-			WHERE m.is_dm = 1 AND m.id < ?
-			AND ((m.user_id = ? AND m.dm_target_id = ?)
-			  OR (m.user_id = ? AND m.dm_target_id = ?))
-			ORDER BY m.id DESC LIMIT ?`,
-			[]any{beforeID, userA, userB, userB, userA, limit}
-	}
-
-	return `SELECT m.id, u.nick, m.content, t.nick, m.created_at
-		FROM messages m
-		INNER JOIN users u ON u.id = m.user_id
-		INNER JOIN users t ON t.id = m.dm_target_id
-		WHERE m.is_dm = 1
-		AND ((m.user_id = ? AND m.dm_target_id = ?)
-		  OR (m.user_id = ? AND m.dm_target_id = ?))
-		ORDER BY m.id DESC LIMIT ?`,
-		[]any{userA, userB, userB, userA, limit}
-}
-
-func reverseMessages(msgs []MessageInfo) {
-	for i, j := 0, len(msgs)-1; i < j; i, j = i+1, j-1 {
-		msgs[i], msgs[j] = msgs[j], msgs[i]
-	}
-}

internal/db/schema/003_users.sql

@@ -1,16 +1,53 @@
--- Migration 003: Add simple user auth columns.
--- This migration adds token-based auth support for the web client.
--- Tables created by 002 (with TEXT ids) take precedence via IF NOT EXISTS.
--- We only add columns/indexes that don't already exist.
+-- Migration 003: Replace UUID-based tables with simple integer-keyed
+-- tables for the HTTP API.  Drops the 002 tables and recreates them.
 
--- Add token column to users table if it doesn't exist.
--- SQLite doesn't support IF NOT EXISTS for ALTER TABLE ADD COLUMN,
--- so we check via pragma first.
-CREATE TABLE IF NOT EXISTS _migration_003_check (done INTEGER);
-INSERT OR IGNORE INTO _migration_003_check VALUES (1);
+PRAGMA foreign_keys = OFF;
 
--- The web chat client's simple tables are only created if migration 002
--- didn't already create them with the ORM schema.
--- Since 002 creates all needed tables, 003 is effectively a no-op
--- when run after 002.
-DROP TABLE IF EXISTS _migration_003_check;
+DROP TABLE IF EXISTS message_queue;
+DROP TABLE IF EXISTS sessions;
+DROP TABLE IF EXISTS server_links;
+DROP TABLE IF EXISTS messages;
+DROP TABLE IF EXISTS channel_members;
+DROP TABLE IF EXISTS auth_tokens;
+DROP TABLE IF EXISTS channels;
+DROP TABLE IF EXISTS users;
+
+CREATE TABLE users (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    nick TEXT NOT NULL UNIQUE,
+    token TEXT NOT NULL UNIQUE,
+    created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
+    last_seen DATETIME DEFAULT CURRENT_TIMESTAMP
+);
+
+CREATE TABLE channels (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    name TEXT NOT NULL UNIQUE,
+    topic TEXT NOT NULL DEFAULT '',
+    created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
+    updated_at DATETIME DEFAULT CURRENT_TIMESTAMP
+);
+
+CREATE TABLE channel_members (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    channel_id INTEGER NOT NULL REFERENCES channels(id) ON DELETE CASCADE,
+    user_id INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    joined_at DATETIME DEFAULT CURRENT_TIMESTAMP,
+    UNIQUE(channel_id, user_id)
+);
+
+CREATE TABLE messages (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    channel_id INTEGER REFERENCES channels(id) ON DELETE CASCADE,
+    user_id INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    content TEXT NOT NULL,
+    is_dm INTEGER NOT NULL DEFAULT 0,
+    dm_target_id INTEGER REFERENCES users(id) ON DELETE CASCADE,
+    created_at DATETIME DEFAULT CURRENT_TIMESTAMP
+);
+
+CREATE INDEX idx_messages_channel ON messages(channel_id, created_at);
+CREATE INDEX idx_messages_dm ON messages(user_id, dm_target_id, created_at);
+CREATE INDEX idx_users_token ON users(token);
+
+PRAGMA foreign_keys = ON;

internal/handlers/api.go

@@ -11,10 +11,16 @@ import (
 	"github.com/go-chi/chi"
 )
 
-const maxNickLen = 32
+const (
+	maxNickLen     = 32
+	defaultHistory = 50
+)
 
-// authUser extracts the user from the Authorization header (Bearer token).
-func (s *Handlers) authUser(r *http.Request) (int64, string, error) {
+// authUser extracts the user from the Authorization header
+// (Bearer token).
+func (s *Handlers) authUser(
+	r *http.Request,
+) (int64, string, error) {
 	auth := r.Header.Get("Authorization")
 	if !strings.HasPrefix(auth, "Bearer ") {
 		return 0, "", sql.ErrNoRows
@@ -22,13 +28,20 @@ func (s *Handlers) authUser(r *http.Request) (int64, string, error) {
 
 	token := strings.TrimPrefix(auth, "Bearer ")
 
-	return s.params.Database.LookupUserByToken(r.Context(), token)
+	return s.params.Database.GetUserByToken(r.Context(), token)
 }
 
-func (s *Handlers) requireAuth(w http.ResponseWriter, r *http.Request) (int64, string, bool) {
+func (s *Handlers) requireAuth(
+	w http.ResponseWriter,
+	r *http.Request,
+) (int64, string, bool) {
 	uid, nick, err := s.authUser(r)
 	if err != nil {
-		s.respondJSON(w, r, map[string]string{"error": "unauthorized"}, http.StatusUnauthorized)
+		s.respondJSON(
+			w, r,
+			map[string]string{"error": "unauthorized"},
+			http.StatusUnauthorized,
+		)
 
 		return 0, "", false
 	}
@@ -36,7 +49,48 @@ func (s *Handlers) requireAuth(w http.ResponseWriter, r *http.Request) (int64, s
 	return uid, nick, true
 }
 
-// HandleCreateSession creates a new user session and returns the auth token.
+func (s *Handlers) respondError(
+	w http.ResponseWriter,
+	r *http.Request,
+	msg string,
+	code int,
+) {
+	s.respondJSON(w, r, map[string]string{"error": msg}, code)
+}
+
+func (s *Handlers) internalError(
+	w http.ResponseWriter,
+	r *http.Request,
+	msg string,
+	err error,
+) {
+	s.log.Error(msg, "error", err)
+	s.respondError(w, r, "internal error", http.StatusInternalServerError)
+}
+
+// bodyLines extracts body as string lines from a request body
+// field.
+func bodyLines(body any) []string {
+	switch v := body.(type) {
+	case []any:
+		lines := make([]string, 0, len(v))
+
+		for _, item := range v {
+			if s, ok := item.(string); ok {
+				lines = append(lines, s)
+			}
+		}
+
+		return lines
+	case []string:
+		return v
+	default:
+		return nil
+	}
+}
+
+// HandleCreateSession creates a new user session and returns
+// the auth token.
 func (s *Handlers) HandleCreateSession() http.HandlerFunc {
 	type request struct {
 		Nick string `json:"nick"`
@@ -53,7 +107,10 @@ func (s *Handlers) HandleCreateSession() http.HandlerFunc {
 
 		err := json.NewDecoder(r.Body).Decode(&req)
 		if err != nil {
-			s.respondJSON(w, r, map[string]string{"error": "invalid request"}, http.StatusBadRequest)
+			s.respondError(
+				w, r, "invalid request",
+				http.StatusBadRequest,
+			)
 
 			return
 		}
@@ -61,30 +118,42 @@ func (s *Handlers) HandleCreateSession() http.HandlerFunc {
 		req.Nick = strings.TrimSpace(req.Nick)
 
 		if req.Nick == "" || len(req.Nick) > maxNickLen {
-			s.respondJSON(w, r, map[string]string{"error": "nick must be 1-32 characters"}, http.StatusBadRequest)
+			s.respondError(
+				w, r, "nick must be 1-32 characters",
+				http.StatusBadRequest,
+			)
 
 			return
 		}
 
-		id, token, err := s.params.Database.CreateSimpleUser(r.Context(), req.Nick)
+		id, token, err := s.params.Database.CreateUser(
+			r.Context(), req.Nick,
+		)
 		if err != nil {
 			if strings.Contains(err.Error(), "UNIQUE") {
-				s.respondJSON(w, r, map[string]string{"error": "nick already taken"}, http.StatusConflict)
+				s.respondError(
+					w, r, "nick already taken",
+					http.StatusConflict,
+				)
 
 				return
 			}
 
-			s.log.Error("create user failed", "error", err)
-			s.respondJSON(w, r, map[string]string{"error": "internal error"}, http.StatusInternalServerError)
+			s.internalError(w, r, "create user failed", err)
 
 			return
 		}
 
-		s.respondJSON(w, r, &response{ID: id, Nick: req.Nick, Token: token}, http.StatusCreated)
+		s.respondJSON(
+			w, r,
+			&response{ID: id, Nick: req.Nick, Token: token},
+			http.StatusCreated,
+		)
 	}
 }
 
-// HandleState returns the current user's info and joined channels.
+// HandleState returns the current user's info and joined
+// channels.
 func (s *Handlers) HandleState() http.HandlerFunc {
 	type response struct {
 		ID       int64            `json:"id"`
@@ -98,15 +167,25 @@ func (s *Handlers) HandleState() http.HandlerFunc {
 			return
 		}
 
-		channels, err := s.params.Database.ListChannels(r.Context(), uid)
+		channels, err := s.params.Database.ListChannels(
+			r.Context(), uid,
+		)
 		if err != nil {
-			s.log.Error("list channels failed", "error", err)
-			s.respondJSON(w, r, map[string]string{"error": "internal error"}, http.StatusInternalServerError)
+			s.internalError(
+				w, r, "list channels failed", err,
+			)
 
 			return
 		}
 
-		s.respondJSON(w, r, &response{ID: uid, Nick: nick, Channels: channels}, http.StatusOK)
+		s.respondJSON(
+			w, r,
+			&response{
+				ID: uid, Nick: nick,
+				Channels: channels,
+			},
+			http.StatusOK,
+		)
 	}
 }
 
@@ -118,10 +197,13 @@ func (s *Handlers) HandleListAllChannels() http.HandlerFunc {
 			return
 		}
 
-		channels, err := s.params.Database.ListAllChannels(r.Context())
+		channels, err := s.params.Database.ListAllChannels(
+			r.Context(),
+		)
 		if err != nil {
-			s.log.Error("list all channels failed", "error", err)
-			s.respondJSON(w, r, map[string]string{"error": "internal error"}, http.StatusInternalServerError)
+			s.internalError(
+				w, r, "list all channels failed", err,
+			)
 
 			return
 		}
@@ -140,17 +222,29 @@ func (s *Handlers) HandleChannelMembers() http.HandlerFunc {
 
 		name := "#" + chi.URLParam(r, "channel")
 
-		chID, err := s.lookupChannelID(r, name)
+		var chID int64
+
+		err := s.params.Database.GetDB().QueryRowContext( //nolint:gosec // parameterized query
+			r.Context(),
+			"SELECT id FROM channels WHERE name = ?",
+			name,
+		).Scan(&chID)
 		if err != nil {
-			s.respondJSON(w, r, map[string]string{"error": "channel not found"}, http.StatusNotFound)
+			s.respondError(
+				w, r, "channel not found",
+				http.StatusNotFound,
+			)
 
 			return
 		}
 
-		members, err := s.params.Database.ChannelMembers(r.Context(), chID)
+		members, err := s.params.Database.ChannelMembers(
+			r.Context(), chID,
+		)
 		if err != nil {
-			s.log.Error("channel members failed", "error", err)
-			s.respondJSON(w, r, map[string]string{"error": "internal error"}, http.StatusInternalServerError)
+			s.internalError(
+				w, r, "channel members failed", err,
+			)
 
 			return
 		}
@@ -159,8 +253,8 @@ func (s *Handlers) HandleChannelMembers() http.HandlerFunc {
 	}
 }
 
-// HandleGetMessages returns all new messages (channel + DM) for the user via long-polling.
-// This is the single unified message stream — replaces separate channel/DM/poll endpoints.
+// HandleGetMessages returns all new messages (channel + DM)
+// for the user via long-polling.
 func (s *Handlers) HandleGetMessages() http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		uid, _, ok := s.requireAuth(w, r)
@@ -168,13 +262,21 @@ func (s *Handlers) HandleGetMessages() http.HandlerFunc {
 			return
 		}
 
-		afterID, _ := strconv.ParseInt(r.URL.Query().Get("after"), 10, 64)
-		limit, _ := strconv.Atoi(r.URL.Query().Get("limit"))
+		afterID, _ := strconv.ParseInt(
+			r.URL.Query().Get("after"), 10, 64,
+		)
 
-		msgs, err := s.params.Database.PollMessages(r.Context(), uid, afterID, limit)
+		limit, _ := strconv.Atoi(
+			r.URL.Query().Get("limit"),
+		)
+
+		msgs, err := s.params.Database.PollMessages(
+			r.Context(), uid, afterID, limit,
+		)
 		if err != nil {
-			s.log.Error("get messages failed", "error", err)
-			s.respondJSON(w, r, map[string]string{"error": "internal error"}, http.StatusInternalServerError)
+			s.internalError(
+				w, r, "get messages failed", err,
+			)
 
 			return
 		}
@@ -183,8 +285,15 @@ func (s *Handlers) HandleGetMessages() http.HandlerFunc {
 	}
 }
 
-// HandleSendCommand handles all C2S commands via POST /messages.
-// The "command" field dispatches to the appropriate logic.
+type sendRequest struct {
+	Command string   `json:"command"`
+	To      string   `json:"to"`
+	Params  []string `json:"params,omitempty"`
+	Body    any      `json:"body,omitempty"`
+}
+
+// HandleSendCommand handles all C2S commands via POST
+// /messages.
 func (s *Handlers) HandleSendCommand() http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		uid, nick, ok := s.requireAuth(w, r)
@@ -192,275 +301,373 @@ func (s *Handlers) HandleSendCommand() http.HandlerFunc {
 			return
 		}
 
-		cmd, err := s.decodeSendCommand(r)
+		var req sendRequest
+
+		err := json.NewDecoder(r.Body).Decode(&req)
 		if err != nil {
-			s.respondJSON(w, r, map[string]string{"error": "invalid request"}, http.StatusBadRequest)
+			s.respondError(
+				w, r, "invalid request",
+				http.StatusBadRequest,
+			)
 
 			return
 		}
 
-		switch cmd.Command {
-		case "PRIVMSG", "NOTICE":
-			s.handlePrivmsgCommand(w, r, uid, cmd)
-		case "JOIN":
-			s.handleJoinCommand(w, r, uid, cmd)
-		case "PART":
-			s.handlePartCommand(w, r, uid, cmd)
-		case "NICK":
-			s.handleNickCommand(w, r, uid, cmd)
-		case "TOPIC":
-			s.handleTopicCommand(w, r, cmd)
-		case "PING":
-			s.respondJSON(w, r, map[string]string{"command": "PONG", "from": s.params.Config.ServerName}, http.StatusOK)
-		default:
-			_ = nick // suppress unused warning
+		req.Command = strings.ToUpper(
+			strings.TrimSpace(req.Command),
+		)
+		req.To = strings.TrimSpace(req.To)
 
-			s.respondJSON(w, r, map[string]string{"error": "unknown command: " + cmd.Command}, http.StatusBadRequest)
-		}
+		s.dispatchCommand(w, r, uid, nick, &req)
 	}
 }
 
-type sendCommand struct {
-	Command string   `json:"command"`
-	To      string   `json:"to"`
-	Params  []string `json:"params,omitempty"`
-	Body    any      `json:"body,omitempty"`
-}
-
-func (s *Handlers) decodeSendCommand(r *http.Request) (*sendCommand, error) {
-	var cmd sendCommand
-
-	err := json.NewDecoder(r.Body).Decode(&cmd)
-	if err != nil {
-		return nil, err
-	}
-
-	cmd.Command = strings.ToUpper(strings.TrimSpace(cmd.Command))
-	cmd.To = strings.TrimSpace(cmd.To)
-
-	return &cmd, nil
-}
-
-func bodyLines(body any) []string {
-	switch v := body.(type) {
-	case []any:
-		lines := make([]string, 0, len(v))
-
-		for _, item := range v {
-			if str, ok := item.(string); ok {
-				lines = append(lines, str)
-			}
-		}
-
-		return lines
-	case []string:
-		return v
-	default:
-		return nil
-	}
-}
-
-func (s *Handlers) handlePrivmsgCommand(
-	w http.ResponseWriter, r *http.Request, uid int64, cmd *sendCommand,
+func (s *Handlers) dispatchCommand(
+	w http.ResponseWriter,
+	r *http.Request,
+	uid int64,
+	nick string,
+	req *sendRequest,
 ) {
-	if cmd.To == "" {
-		s.respondJSON(w, r, map[string]string{"error": "to field required"}, http.StatusBadRequest)
+	switch req.Command {
+	case "PRIVMSG", "NOTICE":
+		s.handlePrivmsg(w, r, uid, req)
+	case "JOIN":
+		s.handleJoin(w, r, uid, req)
+	case "PART":
+		s.handlePart(w, r, uid, req)
+	case "NICK":
+		s.handleNick(w, r, uid, req)
+	case "TOPIC":
+		s.handleTopic(w, r, uid, req)
+	case "PING":
+		s.respondJSON(
+			w, r,
+			map[string]string{
+				"command": "PONG",
+				"from":    s.params.Config.ServerName,
+			},
+			http.StatusOK,
+		)
+	default:
+		_ = nick
+
+		s.respondError(
+			w, r,
+			"unknown command: "+req.Command,
+			http.StatusBadRequest,
+		)
+	}
+}
+
+func (s *Handlers) handlePrivmsg(
+	w http.ResponseWriter,
+	r *http.Request,
+	uid int64,
+	req *sendRequest,
+) {
+	if req.To == "" {
+		s.respondError(
+			w, r, "to field required",
+			http.StatusBadRequest,
+		)
 
 		return
 	}
 
-	lines := bodyLines(cmd.Body)
+	lines := bodyLines(req.Body)
 	if len(lines) == 0 {
-		s.respondJSON(w, r, map[string]string{"error": "body required"}, http.StatusBadRequest)
+		s.respondError(
+			w, r, "body required", http.StatusBadRequest,
+		)
 
 		return
 	}
 
 	content := strings.Join(lines, "\n")
 
-	if strings.HasPrefix(cmd.To, "#") {
-		s.sendChannelMessage(w, r, uid, cmd.To, content)
+	if strings.HasPrefix(req.To, "#") {
+		s.sendChannelMsg(w, r, uid, req.To, content)
 	} else {
-		s.sendDirectMessage(w, r, uid, cmd.To, content)
+		s.sendDM(w, r, uid, req.To, content)
 	}
 }
 
-func (s *Handlers) sendChannelMessage(
-	w http.ResponseWriter, r *http.Request, uid int64, channel, content string,
+func (s *Handlers) sendChannelMsg(
+	w http.ResponseWriter,
+	r *http.Request,
+	uid int64,
+	channel, content string,
 ) {
-	chID, err := s.lookupChannelID(r, channel)
+	var chID int64
+
+	err := s.params.Database.GetDB().QueryRowContext( //nolint:gosec // parameterized query
+		r.Context(),
+		"SELECT id FROM channels WHERE name = ?",
+		channel,
+	).Scan(&chID)
 	if err != nil {
-		s.respondJSON(w, r, map[string]string{"error": "channel not found"}, http.StatusNotFound)
+		s.respondError(
+			w, r, "channel not found",
+			http.StatusNotFound,
+		)
 
 		return
 	}
 
-	msgID, err := s.params.Database.SendMessage(r.Context(), chID, uid, content)
+	msgID, err := s.params.Database.SendMessage(
+		r.Context(), chID, uid, content,
+	)
 	if err != nil {
-		s.log.Error("send message failed", "error", err)
-		s.respondJSON(w, r, map[string]string{"error": "internal error"}, http.StatusInternalServerError)
+		s.internalError(w, r, "send message failed", err)
 
 		return
 	}
 
-	s.respondJSON(w, r, map[string]any{"id": msgID, "status": "sent"}, http.StatusCreated)
+	s.respondJSON(
+		w, r,
+		map[string]any{"id": msgID, "status": "sent"},
+		http.StatusCreated,
+	)
 }
 
-func (s *Handlers) sendDirectMessage(
-	w http.ResponseWriter, r *http.Request, uid int64, toNick, content string,
+func (s *Handlers) sendDM(
+	w http.ResponseWriter,
+	r *http.Request,
+	uid int64,
+	toNick, content string,
 ) {
-	targetID, err := s.params.Database.LookupUserByNick(r.Context(), toNick)
+	targetID, err := s.params.Database.GetUserByNick(
+		r.Context(), toNick,
+	)
 	if err != nil {
-		s.respondJSON(w, r, map[string]string{"error": "user not found"}, http.StatusNotFound)
+		s.respondError(
+			w, r, "user not found", http.StatusNotFound,
+		)
 
 		return
 	}
 
-	msgID, err := s.params.Database.SendDM(r.Context(), uid, targetID, content)
+	msgID, err := s.params.Database.SendDM(
+		r.Context(), uid, targetID, content,
+	)
 	if err != nil {
-		s.log.Error("send dm failed", "error", err)
-		s.respondJSON(w, r, map[string]string{"error": "internal error"}, http.StatusInternalServerError)
+		s.internalError(w, r, "send dm failed", err)
 
 		return
 	}
 
-	s.respondJSON(w, r, map[string]any{"id": msgID, "status": "sent"}, http.StatusCreated)
+	s.respondJSON(
+		w, r,
+		map[string]any{"id": msgID, "status": "sent"},
+		http.StatusCreated,
+	)
 }
 
-func (s *Handlers) handleJoinCommand(
-	w http.ResponseWriter, r *http.Request, uid int64, cmd *sendCommand,
+func (s *Handlers) handleJoin(
+	w http.ResponseWriter,
+	r *http.Request,
+	uid int64,
+	req *sendRequest,
 ) {
-	if cmd.To == "" {
-		s.respondJSON(w, r, map[string]string{"error": "to field required"}, http.StatusBadRequest)
+	if req.To == "" {
+		s.respondError(
+			w, r, "to field required",
+			http.StatusBadRequest,
+		)
 
 		return
 	}
 
-	channel := cmd.To
+	channel := req.To
 	if !strings.HasPrefix(channel, "#") {
 		channel = "#" + channel
 	}
 
-	chID, err := s.params.Database.GetOrCreateChannel(r.Context(), channel)
+	chID, err := s.params.Database.GetOrCreateChannel(
+		r.Context(), channel,
+	)
 	if err != nil {
-		s.log.Error("get/create channel failed", "error", err)
-		s.respondJSON(w, r, map[string]string{"error": "internal error"}, http.StatusInternalServerError)
+		s.internalError(
+			w, r, "get/create channel failed", err,
+		)
 
 		return
 	}
 
-	err = s.params.Database.JoinChannel(r.Context(), chID, uid)
+	err = s.params.Database.JoinChannel(
+		r.Context(), chID, uid,
+	)
 	if err != nil {
-		s.log.Error("join channel failed", "error", err)
-		s.respondJSON(w, r, map[string]string{"error": "internal error"}, http.StatusInternalServerError)
+		s.internalError(w, r, "join channel failed", err)
 
 		return
 	}
 
-	s.respondJSON(w, r, map[string]string{"status": "joined", "channel": channel}, http.StatusOK)
+	s.respondJSON(
+		w, r,
+		map[string]string{
+			"status": "joined", "channel": channel,
+		},
+		http.StatusOK,
+	)
 }
 
-func (s *Handlers) handlePartCommand(
-	w http.ResponseWriter, r *http.Request, uid int64, cmd *sendCommand,
+func (s *Handlers) handlePart(
+	w http.ResponseWriter,
+	r *http.Request,
+	uid int64,
+	req *sendRequest,
 ) {
-	if cmd.To == "" {
-		s.respondJSON(w, r, map[string]string{"error": "to field required"}, http.StatusBadRequest)
+	if req.To == "" {
+		s.respondError(
+			w, r, "to field required",
+			http.StatusBadRequest,
+		)
 
 		return
 	}
 
-	channel := cmd.To
+	channel := req.To
 	if !strings.HasPrefix(channel, "#") {
 		channel = "#" + channel
 	}
 
-	chID, err := s.lookupChannelID(r, channel)
+	var chID int64
+
+	err := s.params.Database.GetDB().QueryRowContext( //nolint:gosec // parameterized query
+		r.Context(),
+		"SELECT id FROM channels WHERE name = ?",
+		channel,
+	).Scan(&chID)
 	if err != nil {
-		s.respondJSON(w, r, map[string]string{"error": "channel not found"}, http.StatusNotFound)
+		s.respondError(
+			w, r, "channel not found",
+			http.StatusNotFound,
+		)
 
 		return
 	}
 
-	err = s.params.Database.PartChannel(r.Context(), chID, uid)
+	err = s.params.Database.PartChannel(
+		r.Context(), chID, uid,
+	)
 	if err != nil {
-		s.log.Error("part channel failed", "error", err)
-		s.respondJSON(w, r, map[string]string{"error": "internal error"}, http.StatusInternalServerError)
+		s.internalError(w, r, "part channel failed", err)
 
 		return
 	}
 
-	s.respondJSON(w, r, map[string]string{"status": "parted", "channel": channel}, http.StatusOK)
+	s.respondJSON(
+		w, r,
+		map[string]string{
+			"status": "parted", "channel": channel,
+		},
+		http.StatusOK,
+	)
 }
 
-func (s *Handlers) handleNickCommand(
-	w http.ResponseWriter, r *http.Request, uid int64, cmd *sendCommand,
+func (s *Handlers) handleNick(
+	w http.ResponseWriter,
+	r *http.Request,
+	uid int64,
+	req *sendRequest,
 ) {
-	lines := bodyLines(cmd.Body)
+	lines := bodyLines(req.Body)
 	if len(lines) == 0 {
-		s.respondJSON(w, r, map[string]string{"error": "body required (new nick)"}, http.StatusBadRequest)
+		s.respondError(
+			w, r, "body required (new nick)",
+			http.StatusBadRequest,
+		)
 
 		return
 	}
 
 	newNick := strings.TrimSpace(lines[0])
 	if newNick == "" || len(newNick) > maxNickLen {
-		s.respondJSON(w, r, map[string]string{"error": "nick must be 1-32 characters"}, http.StatusBadRequest)
+		s.respondError(
+			w, r, "nick must be 1-32 characters",
+			http.StatusBadRequest,
+		)
 
 		return
 	}
 
-	err := s.params.Database.ChangeNick(r.Context(), uid, newNick)
+	err := s.params.Database.ChangeNick(
+		r.Context(), uid, newNick,
+	)
 	if err != nil {
 		if strings.Contains(err.Error(), "UNIQUE") {
-			s.respondJSON(w, r, map[string]string{"error": "nick already in use"}, http.StatusConflict)
+			s.respondError(
+				w, r, "nick already in use",
+				http.StatusConflict,
+			)
 
 			return
 		}
 
-		s.log.Error("change nick failed", "error", err)
-		s.respondJSON(w, r, map[string]string{"error": "internal error"}, http.StatusInternalServerError)
+		s.internalError(w, r, "change nick failed", err)
 
 		return
 	}
 
-	s.respondJSON(w, r, map[string]string{"status": "ok", "nick": newNick}, http.StatusOK)
+	s.respondJSON(
+		w, r,
+		map[string]string{"status": "ok", "nick": newNick},
+		http.StatusOK,
+	)
 }
 
-func (s *Handlers) handleTopicCommand(
-	w http.ResponseWriter, r *http.Request, cmd *sendCommand,
+func (s *Handlers) handleTopic(
+	w http.ResponseWriter,
+	r *http.Request,
+	uid int64,
+	req *sendRequest,
 ) {
-	if cmd.To == "" {
-		s.respondJSON(w, r, map[string]string{"error": "to field required"}, http.StatusBadRequest)
+	if req.To == "" {
+		s.respondError(
+			w, r, "to field required",
+			http.StatusBadRequest,
+		)
 
 		return
 	}
 
-	lines := bodyLines(cmd.Body)
+	lines := bodyLines(req.Body)
 	if len(lines) == 0 {
-		s.respondJSON(w, r, map[string]string{"error": "body required (topic text)"}, http.StatusBadRequest)
+		s.respondError(
+			w, r, "body required (topic text)",
+			http.StatusBadRequest,
+		)
 
 		return
 	}
 
 	topic := strings.Join(lines, " ")
 
-	channel := cmd.To
+	channel := req.To
 	if !strings.HasPrefix(channel, "#") {
 		channel = "#" + channel
 	}
 
-	err := s.params.Database.SetTopic(r.Context(), channel, 0, topic)
+	err := s.params.Database.SetTopic(
+		r.Context(), channel, uid, topic,
+	)
 	if err != nil {
-		s.log.Error("set topic failed", "error", err)
-		s.respondJSON(w, r, map[string]string{"error": "internal error"}, http.StatusInternalServerError)
+		s.internalError(w, r, "set topic failed", err)
 
 		return
 	}
 
-	s.respondJSON(w, r, map[string]string{"status": "ok", "topic": topic}, http.StatusOK)
+	s.respondJSON(
+		w, r,
+		map[string]string{"status": "ok", "topic": topic},
+		http.StatusOK,
+	)
 }
 
-// HandleGetHistory returns message history for a specific target (channel or DM).
+// HandleGetHistory returns message history for a specific
+// target (channel or DM).
 func (s *Handlers) HandleGetHistory() http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		uid, _, ok := s.requireAuth(w, r)
@@ -470,81 +677,103 @@ func (s *Handlers) HandleGetHistory() http.HandlerFunc {
 
 		target := r.URL.Query().Get("target")
 		if target == "" {
-			s.respondJSON(w, r, map[string]string{"error": "target required"}, http.StatusBadRequest)
+			s.respondError(
+				w, r, "target required",
+				http.StatusBadRequest,
+			)
 
 			return
 		}
 
-		beforeID, _ := strconv.ParseInt(r.URL.Query().Get("before"), 10, 64)
+		beforeID, _ := strconv.ParseInt(
+			r.URL.Query().Get("before"), 10, 64,
+		)
 
-		limit, _ := strconv.Atoi(r.URL.Query().Get("limit"))
+		limit, _ := strconv.Atoi(
+			r.URL.Query().Get("limit"),
+		)
 		if limit <= 0 {
-			limit = defaultHistoryLimit
+			limit = defaultHistory
 		}
 
 		if strings.HasPrefix(target, "#") {
-			s.handleChannelHistory(w, r, target, beforeID, limit)
+			s.getChannelHistory(
+				w, r, target, beforeID, limit,
+			)
 		} else {
-			s.handleDMHistory(w, r, uid, target, beforeID, limit)
+			s.getDMHistory(
+				w, r, uid, target, beforeID, limit,
+			)
 		}
 	}
 }
 
-const defaultHistoryLimit = 50
-
-func (s *Handlers) handleChannelHistory(
-	w http.ResponseWriter, r *http.Request,
-	target string, beforeID int64, limit int,
+func (s *Handlers) getChannelHistory(
+	w http.ResponseWriter,
+	r *http.Request,
+	target string,
+	beforeID int64,
+	limit int,
 ) {
-	chID, err := s.lookupChannelID(r, target)
-	if err != nil {
-		s.respondJSON(w, r, map[string]string{"error": "channel not found"}, http.StatusNotFound)
-
-		return
-	}
-
-	msgs, err := s.params.Database.GetMessagesBefore(r.Context(), chID, beforeID, limit)
-	if err != nil {
-		s.log.Error("get history failed", "error", err)
-		s.respondJSON(w, r, map[string]string{"error": "internal error"}, http.StatusInternalServerError)
-
-		return
-	}
-
-	s.respondJSON(w, r, msgs, http.StatusOK)
-}
-
-func (s *Handlers) handleDMHistory(
-	w http.ResponseWriter, r *http.Request,
-	uid int64, target string, beforeID int64, limit int,
-) {
-	targetID, err := s.params.Database.LookupUserByNick(r.Context(), target)
-	if err != nil {
-		s.respondJSON(w, r, map[string]string{"error": "user not found"}, http.StatusNotFound)
-
-		return
-	}
-
-	msgs, err := s.params.Database.GetDMsBefore(r.Context(), uid, targetID, beforeID, limit)
-	if err != nil {
-		s.log.Error("get dm history failed", "error", err)
-		s.respondJSON(w, r, map[string]string{"error": "internal error"}, http.StatusInternalServerError)
-
-		return
-	}
-
-	s.respondJSON(w, r, msgs, http.StatusOK)
-}
-
-// lookupChannelID queries the channel ID by name using a parameterized query.
-func (s *Handlers) lookupChannelID(r *http.Request, name string) (int64, error) {
 	var chID int64
 
-	//nolint:gosec // query uses parameterized placeholder (?), not string interpolation
-	err := s.params.Database.GetDB().QueryRowContext(r.Context(),
-		"SELECT id FROM channels WHERE name = ?", name).Scan(&chID)
+	err := s.params.Database.GetDB().QueryRowContext( //nolint:gosec // parameterized query
+		r.Context(),
+		"SELECT id FROM channels WHERE name = ?",
+		target,
+	).Scan(&chID)
+	if err != nil {
+		s.respondError(
+			w, r, "channel not found",
+			http.StatusNotFound,
+		)
 
-	return chID, err
+		return
+	}
+
+	msgs, err := s.params.Database.GetMessagesBefore(
+		r.Context(), chID, beforeID, limit,
+	)
+	if err != nil {
+		s.internalError(w, r, "get history failed", err)
+
+		return
+	}
+
+	s.respondJSON(w, r, msgs, http.StatusOK)
+}
+
+func (s *Handlers) getDMHistory(
+	w http.ResponseWriter,
+	r *http.Request,
+	uid int64,
+	target string,
+	beforeID int64,
+	limit int,
+) {
+	targetID, err := s.params.Database.GetUserByNick(
+		r.Context(), target,
+	)
+	if err != nil {
+		s.respondError(
+			w, r, "user not found", http.StatusNotFound,
+		)
+
+		return
+	}
+
+	msgs, err := s.params.Database.GetDMsBefore(
+		r.Context(), uid, targetID, beforeID, limit,
+	)
+	if err != nil {
+		s.internalError(
+			w, r, "get dm history failed", err,
+		)
+
+		return
+	}
+
+	s.respondJSON(w, r, msgs, http.StatusOK)
 }
 
 // HandleServerInfo returns server metadata (MOTD, name).

internal/models/auth_token.go

@@ -2,13 +2,9 @@ package models
 
 import (
 	"context"
-	"errors"
 	"time"
 )
 
-// ErrUserLookupNotAvailable is returned when user lookup is not configured.
-var ErrUserLookupNotAvailable = errors.New("user lookup not available")
-
 // AuthToken represents an authentication token for a user session.
 type AuthToken struct {
 	Base
@@ -22,5 +18,9 @@ type AuthToken struct {
 
 // User returns the user who owns this token.
 func (t *AuthToken) User(ctx context.Context) (*User, error) {
-	return t.LookupUser(ctx, t.UserID)
+	if ul := t.GetUserLookup(); ul != nil {
+		return ul.GetUserByID(ctx, t.UserID)
+	}
+
+	return nil, ErrUserLookupNotAvailable
 }

internal/models/channel_member.go

@@ -2,13 +2,9 @@ package models
 
 import (
 	"context"
-	"errors"
 	"time"
 )
 
-// ErrChannelLookupNotAvailable is returned when channel lookup is not configured.
-var ErrChannelLookupNotAvailable = errors.New("channel lookup not available")
-
 // ChannelMember represents a user's membership in a channel.
 type ChannelMember struct {
 	Base
@@ -22,10 +18,18 @@ type ChannelMember struct {
 
 // User returns the full User for this membership.
 func (cm *ChannelMember) User(ctx context.Context) (*User, error) {
-	return cm.LookupUser(ctx, cm.UserID)
+	if ul := cm.GetUserLookup(); ul != nil {
+		return ul.GetUserByID(ctx, cm.UserID)
+	}
+
+	return nil, ErrUserLookupNotAvailable
 }
 
 // Channel returns the full Channel for this membership.
 func (cm *ChannelMember) Channel(ctx context.Context) (*Channel, error) {
-	return cm.LookupChannel(ctx, cm.ChannelID)
+	if cl := cm.GetChannelLookup(); cl != nil {
+		return cl.GetChannelByID(ctx, cm.ChannelID)
+	}
+
+	return nil, ErrChannelLookupNotAvailable
 }

internal/models/model.go

@@ -6,6 +6,7 @@ package models
 import (
 	"context"
 	"database/sql"
+	"errors"
 )
 
 // DB is the interface that models use to query the database.
@@ -24,6 +25,12 @@ type ChannelLookup interface {
 	GetChannelByID(ctx context.Context, id string) (*Channel, error)
 }
 
+// Sentinel errors for model lookup methods.
+var (
+	ErrUserLookupNotAvailable    = errors.New("user lookup not available")
+	ErrChannelLookupNotAvailable = errors.New("channel lookup not available")
+)
+
 // Base is embedded in all model structs to provide database access.
 type Base struct {
 	db DB
@@ -39,22 +46,20 @@ func (b *Base) GetDB() *sql.DB {
 	return b.db.GetDB()
 }
 
-// LookupUser looks up a user by ID if the database supports it.
-func (b *Base) LookupUser(ctx context.Context, id string) (*User, error) {
-	ul, ok := b.db.(UserLookup)
-	if !ok {
-		return nil, ErrUserLookupNotAvailable
+// GetUserLookup returns the DB as a UserLookup if it implements the interface.
+func (b *Base) GetUserLookup() UserLookup { //nolint:ireturn
+	if ul, ok := b.db.(UserLookup); ok {
+		return ul
 	}
 
-	return ul.GetUserByID(ctx, id)
+	return nil
 }
 
-// LookupChannel looks up a channel by ID if the database supports it.
-func (b *Base) LookupChannel(ctx context.Context, id string) (*Channel, error) {
-	cl, ok := b.db.(ChannelLookup)
-	if !ok {
-		return nil, ErrChannelLookupNotAvailable
+// GetChannelLookup returns the DB as a ChannelLookup if it implements the interface.
+func (b *Base) GetChannelLookup() ChannelLookup { //nolint:ireturn
+	if cl, ok := b.db.(ChannelLookup); ok {
+		return cl
 	}
 
-	return cl.GetChannelByID(ctx, id)
+	return nil
 }

internal/models/session.go

@@ -18,5 +18,9 @@ type Session struct {
 
 // User returns the user who owns this session.
 func (s *Session) User(ctx context.Context) (*User, error) {
-	return s.LookupUser(ctx, s.UserID)
+	if ul := s.GetUserLookup(); ul != nil {
+		return ul.GetUserByID(ctx, s.UserID)
+	}
+
+	return nil, ErrUserLookupNotAvailable
 }

internal/server/routes.go

@@ -20,13 +20,6 @@ const routeTimeout = 60 * time.Second
 func (s *Server) SetupRoutes() {
 	s.router = chi.NewRouter()
 
-	s.setupMiddleware()
-	s.setupHealthAndMetrics()
-	s.setupAPIRoutes()
-	s.setupSPA()
-}
-
-func (s *Server) setupMiddleware() {
 	s.router.Use(middleware.Recoverer)
 	s.router.Use(middleware.RequestID)
 	s.router.Use(s.mw.Logging())
@@ -44,54 +37,63 @@ func (s *Server) setupMiddleware() {
 		})
 		s.router.Use(sentryHandler.Handle)
 	}
-}
 
-func (s *Server) setupHealthAndMetrics() {
+	// Health check
 	s.router.Get("/.well-known/healthcheck.json", s.h.HandleHealthCheck())
 
+	// Protected metrics endpoint
 	if viper.GetString("METRICS_USERNAME") != "" {
 		s.router.Group(func(r chi.Router) {
 			r.Use(s.mw.MetricsAuth())
 			r.Get("/metrics", http.HandlerFunc(promhttp.Handler().ServeHTTP))
 		})
 	}
-}
 
-func (s *Server) setupAPIRoutes() {
+	// API v1
 	s.router.Route("/api/v1", func(r chi.Router) {
 		r.Get("/server", s.h.HandleServerInfo())
 		r.Post("/session", s.h.HandleCreateSession())
 
+		// Unified state and message endpoints
 		r.Get("/state", s.h.HandleState())
 		r.Get("/messages", s.h.HandleGetMessages())
 		r.Post("/messages", s.h.HandleSendCommand())
 		r.Get("/history", s.h.HandleGetHistory())
 
+		// Channels
 		r.Get("/channels", s.h.HandleListAllChannels())
 		r.Get("/channels/{channel}/members", s.h.HandleChannelMembers())
 	})
-}
 
-func (s *Server) setupSPA() {
+	// Serve embedded SPA
 	distFS, err := fs.Sub(web.Dist, "dist")
 	if err != nil {
 		s.log.Error("failed to get web dist filesystem", "error", err)
-
-		return
-	}
-
+	} else {
 		fileServer := http.FileServer(http.FS(distFS))
 
 		s.router.Get("/*", func(w http.ResponseWriter, r *http.Request) {
+			s.serveSPA(distFS, fileServer, w, r)
+		})
+	}
+}
+
+func (s *Server) serveSPA(
+	distFS fs.FS,
+	fileServer http.Handler,
+	w http.ResponseWriter,
+	r *http.Request,
+) {
 	readFS, ok := distFS.(fs.ReadFileFS)
 	if !ok {
-			http.NotFound(w, r)
+		http.Error(w, "filesystem error", http.StatusInternalServerError)
 
 		return
 	}
 
-		f, readErr := readFS.ReadFile(r.URL.Path[1:])
-		if readErr != nil || len(f) == 0 {
+	// Try to serve the file; fall back to index.html for SPA routing.
+	f, err := readFS.ReadFile(r.URL.Path[1:])
+	if err != nil || len(f) == 0 {
 		indexHTML, _ := readFS.ReadFile("index.html")
 
 		w.Header().Set("Content-Type", "text/html; charset=utf-8")
@@ -102,5 +104,4 @@ func (s *Server) setupSPA() {
 	}
 
 	fileServer.ServeHTTP(w, r)
-	})
 }