package cli //nolint:testpackage // shares hermeticConfig and the capture helpers

import (
	"context"
	"database/sql"
	"encoding/json"
	"fmt"
	"os"
	"path/filepath"
	"testing"
	"time"

	"github.com/adrg/xdg"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
	"sneak.berlin/go/vaultik/internal/database"
	"sneak.berlin/go/vaultik/internal/types"
)

// pruneJSONDocument is the shape `prune --json` writes: the
// PruneBlobsResult document, and nothing else.
//
//nolint:tagliatelle // snake_case is the established JSON output format
type pruneJSONDocument struct {
	BlobsFound   int   `json:"blobs_found"`
	BlobsDeleted int   `json:"blobs_deleted"`
	BytesFreed   int64 `json:"bytes_freed"`
}

// stalePruneSnapshotID is seeded into the local index with no manifest
// on the destination store, which is exactly what makes it stale.
const stalePruneSnapshotID = "test-host_test_2026-04-01T09:00:00Z"

// TestEntryPruneJSONStdoutIsExactlyOneDocument is the end-to-end
// regression guard for issue #108: `vaultik prune --json | jq .` must
// work with no other flags.
//
// It runs Entry over the process's real stdout descriptor, through
// cobra and the fx graph, against a hermetic file:// destination store
// — the same construction TestEntryJSONStdoutIsExactlyOneDocument uses
// for `snapshot list`, with the pipe to jq replaced by a decoder.
//
// Both branches of the local-snapshot reconciliation are exercised
// because the three stdout writes that broke this covered all of them:
// one line per stale record and a summary when there were any, and a
// "No stale local snapshots found." line when there were none. No input
// avoided the contamination, so no single branch demonstrates the fix.
//
// Not parallel: it replaces os.Args, os.Stdout and the xdg globals.
//
//nolint:paralleltest // replaces os.Args, os.Stdout and the xdg globals
func TestEntryPruneJSONStdoutIsExactlyOneDocument(t *testing.T) {
	for _, testCase := range []struct {
		name        string
		seedStale   bool
		description string
	}{
		{
			name:        "no stale local records",
			seedStale:   false,
			description: "the empty-index branch used to print a 'No stale' line",
		},
		{
			name:      "stale local records present",
			seedStale: true,
			description: "the removal branch used to print a line per record " +
				"plus a summary",
		},
	} {
		t.Run(testCase.name, func(t *testing.T) {
			configPath := writeHermeticPruneConfig(t, testCase.seedStale)

			previousArgs := os.Args

			t.Cleanup(func() {
				os.Args = previousArgs
				rootFlags = RootFlags{}
			})

			os.Args = []string{
				programName, flagConfig, configPath, cmdPrune, flagJSON,
			}

			stdout := captureProcessStdout(t, Entry)

			requireExactlyOneJSONDocument(t, stdout)

			var document pruneJSONDocument

			require.NoError(t, json.Unmarshal([]byte(stdout), &document),
				testCase.description)

			// A destination store with no blobs has none to prune. The
			// assertion that matters is the one above; this one keeps the
			// test honest about which document it decoded.
			assert.Equal(t, 0, document.BlobsFound)
		})
	}
}

// writeHermeticPruneConfig builds a config over a temp directory and, if
// seedStale is set, creates the index database up front with one
// snapshot record that has no counterpart on the destination store.
// Returns the config path.
func writeHermeticPruneConfig(t *testing.T, seedStale bool) string {
	t.Helper()

	dir := t.TempDir()
	configPath := filepath.Join(dir, "config.yml")
	indexPath := filepath.Join(dir, "index.sqlite")

	contents := fmt.Sprintf(hermeticConfig,
		filepath.Join(dir, "source"),
		filepath.Join(dir, "store"),
		indexPath)

	require.NoError(t,
		os.WriteFile(configPath, []byte(contents), configFileMode))

	// The PID lock lives under xdg.DataHome, which xdg resolves at
	// package init; point it at the temp dir so the test neither
	// touches nor collides with the real one.
	t.Setenv("XDG_DATA_HOME", filepath.Join(dir, "data"))
	xdg.Reload()
	t.Cleanup(xdg.Reload)

	if seedStale {
		seedStaleSnapshotRecord(t, indexPath)
	}

	return configPath
}

// seedStaleSnapshotRecord creates the index database at path and
// inserts one completed snapshot into it. Nothing is written to the
// destination store, so `prune` finds the record stale and removes it —
// the branch that printed a line per record.
func seedStaleSnapshotRecord(t *testing.T, path string) {
	t.Helper()

	ctx := context.Background()

	db, err := database.New(ctx, path)
	require.NoError(t, err)

	defer func() { require.NoError(t, db.Close()) }()

	startedAt := time.Date(2026, 4, 1, 9, 0, 0, 0, time.UTC)
	completedAt := startedAt.Add(time.Minute)

	snap := &database.Snapshot{
		ID:             types.SnapshotID(stalePruneSnapshotID),
		Hostname:       "test-host",
		VaultikVersion: "test",
		StartedAt:      startedAt,
		CompletedAt:    &completedAt,
	}

	repos := database.NewRepositories(db)

	err = repos.WithTx(ctx, func(ctx context.Context, tx *sql.Tx) error {
		return repos.Snapshots.Create(ctx, tx, snap)
	})
	require.NoError(t, err)
}