feat: add GitHub and GitLab webhook support

Add auto-detection of webhook source (Gitea, GitHub, GitLab) by
examining HTTP headers (X-Gitea-Event, X-GitHub-Event, X-Gitlab-Event).

Parse push webhook payloads from all three platforms into a normalized
PushEvent type for unified processing. Each platform's payload format
is handled by dedicated parser functions with correct field mapping
and commit URL extraction.

The webhook handler now detects the source automatically — existing
Gitea webhooks continue to work unchanged, while GitHub and GitLab
webhooks are parsed with their respective payload formats.

Includes comprehensive tests for source detection, event type
extraction, payload parsing for all three platforms, commit URL
fallback logic, and integration tests via HandleWebhook.

internal/service/webhook/webhook.go

@@ -4,7 +4,6 @@ package webhook
 import (
 	"context"
 	"database/sql"
-	"encoding/json"
 	"fmt"
 	"log/slog"
 
@@ -44,68 +43,46 @@ func New(_ fx.Lifecycle, params ServiceParams) (*Service, error) {
 	}, nil
 }
 
-// GiteaPushPayload represents a Gitea push webhook payload.
-//
-//nolint:tagliatelle // Field names match Gitea API (snake_case)
-type GiteaPushPayload struct {
-	Ref        string      `json:"ref"`
-	Before     string      `json:"before"`
-	After      string      `json:"after"`
-	CompareURL UnparsedURL `json:"compare_url"`
-	Repository struct {
-		FullName string      `json:"full_name"`
-		CloneURL UnparsedURL `json:"clone_url"`
-		SSHURL   string      `json:"ssh_url"`
-		HTMLURL  UnparsedURL `json:"html_url"`
-	} `json:"repository"`
-	Pusher struct {
-		Username string `json:"username"`
-		Email    string `json:"email"`
-	} `json:"pusher"`
-	Commits []struct {
-		ID      string      `json:"id"`
-		URL     UnparsedURL `json:"url"`
-		Message string      `json:"message"`
-		Author  struct {
-			Name  string `json:"name"`
-			Email string `json:"email"`
-		} `json:"author"`
-	} `json:"commits"`
-}
-
-// HandleWebhook processes a webhook request.
+// HandleWebhook processes a webhook request from any supported source
+// (Gitea, GitHub, or GitLab). The source parameter determines which
+// payload format to use for parsing.
 func (svc *Service) HandleWebhook(
 	ctx context.Context,
 	app *models.App,
+	source Source,
 	eventType string,
 	payload []byte,
 ) error {
-	svc.log.Info("processing webhook", "app", app.Name, "event", eventType)
+	svc.log.Info("processing webhook",
+		"app", app.Name,
+		"source", source.String(),
+		"event", eventType,
+	)
 
-	// Parse payload
-	var pushPayload GiteaPushPayload
-
-	unmarshalErr := json.Unmarshal(payload, &pushPayload)
-	if unmarshalErr != nil {
-		svc.log.Warn("failed to parse webhook payload", "error", unmarshalErr)
-		// Continue anyway to log the event
+	// Parse payload into normalized push event
+	pushEvent, parseErr := ParsePushPayload(source, payload)
+	if parseErr != nil {
+		svc.log.Warn("failed to parse webhook payload",
+			"error", parseErr,
+			"source", source.String(),
+		)
+		// Continue with empty push event to still log the webhook
+		pushEvent = &PushEvent{Source: source}
 	}
 
-	// Extract branch from ref
-	branch := extractBranch(pushPayload.Ref)
-	commitSHA := pushPayload.After
-	commitURL := extractCommitURL(pushPayload)
-
 	// Check if branch matches
-	matched := branch == app.Branch
+	matched := pushEvent.Branch == app.Branch
 
 	// Create webhook event record
 	event := models.NewWebhookEvent(svc.db)
 	event.AppID = app.ID
 	event.EventType = eventType
-	event.Branch = branch
-	event.CommitSHA = sql.NullString{String: commitSHA, Valid: commitSHA != ""}
-	event.CommitURL = sql.NullString{String: commitURL.String(), Valid: commitURL != ""}
+	event.Branch = pushEvent.Branch
+	event.CommitSHA = sql.NullString{String: pushEvent.After, Valid: pushEvent.After != ""}
+	event.CommitURL = sql.NullString{
+		String: pushEvent.CommitURL.String(),
+		Valid:  pushEvent.CommitURL != "",
+	}
 	event.Payload = sql.NullString{String: string(payload), Valid: true}
 	event.Matched = matched
 	event.Processed = false
@@ -117,9 +94,10 @@ func (svc *Service) HandleWebhook(
 
 	svc.log.Info("webhook event recorded",
 		"app", app.Name,
-		"branch", branch,
+		"source", source.String(),
+		"branch", pushEvent.Branch,
 		"matched", matched,
-		"commit", commitSHA,
+		"commit", pushEvent.After,
 	)
 
 	// If branch matches, trigger deployment
@@ -154,33 +132,3 @@ func (svc *Service) triggerDeployment(
 		_ = event.Save(deployCtx)
 	}()
 }
-
-// extractBranch extracts the branch name from a git ref.
-func extractBranch(ref string) string {
-	// refs/heads/main -> main
-	const prefix = "refs/heads/"
-
-	if len(ref) >= len(prefix) && ref[:len(prefix)] == prefix {
-		return ref[len(prefix):]
-	}
-
-	return ref
-}
-
-// extractCommitURL extracts the commit URL from the webhook payload.
-// Prefers the URL from the head commit, falls back to constructing from repo URL.
-func extractCommitURL(payload GiteaPushPayload) UnparsedURL {
-	// Try to find the URL from the head commit (matching After SHA)
-	for _, commit := range payload.Commits {
-		if commit.ID == payload.After && commit.URL != "" {
-			return commit.URL
-		}
-	}
-
-	// Fall back to constructing URL from repo HTML URL
-	if payload.Repository.HTMLURL != "" && payload.After != "" {
-		return UnparsedURL(payload.Repository.HTMLURL.String() + "/commit/" + payload.After)
-	}
-
-	return ""
-}