// Package dbtest provides shared helpers for integration tests that need
// a clean Postgres state without disturbing the operator's admin user.
//
// Background: when integration tests run against the same Postgres
// instance an operator uses for local dev (a common dev-laptop setup),
// a TRUNCATE that includes the users table wipes the operator's admin
// login between every test run. To avoid that, tests should:
//
//  1. Call ResetDB instead of issuing TRUNCATE statements directly. It
//     truncates every data table EXCEPT users, then deletes only those
//     users whose username starts with TestUserPrefix.
//  2. Always create test user rows with a username that begins with
//     TestUserPrefix; otherwise those rows survive across runs and
//     leak into other tests.
//
// One test legitimately needs to wipe the entire users table:
// internal/auth/bootstrap_test.go, which exercises first-time admin
// bootstrap. That file does its own TRUNCATE and does not use this
// helper.
package dbtest

import (
	"context"
	"strings"
	"testing"

	"github.com/jackc/pgx/v5/pgxpool"
)

// TestUserPrefix is the required username prefix for any user row
// created by an integration test. ResetDB removes every user matching
// this prefix and leaves all others intact.
const TestUserPrefix = "test-"

// dataTables is the union of every non-users table touched by any
// integration test in the repo. Truncating the union is harmless for
// callers that only care about a subset; truncating tables that don't
// exist would error, but every name here corresponds to a migration
// that has shipped.
var dataTables = []string{
	"artist_similarity",
	"track_similarity",
	"artist_similarity_unmatched", // M5c
	"scrobble_queue",
	"contextual_likes",
	"general_likes_albums",
	"general_likes_artists",
	"general_likes",
	"play_events",
	"skip_events",
	"play_sessions",
	"sessions",
	"lidarr_quarantine_actions",
	"lidarr_quarantine",
	"playlist_tracks",
	"playlists",
	"library_changes", // M7 #357 — must reset to keep cursor isolated per test
	// SettingsService.reconcile() idempotently re-UpsertProviderSettings
	// for every registered provider at boot, so truncating this is the
	// correct per-test reset (clears test-modified enabled/api_key rows).
	// cover_art_sources_meta is NOT truncated — boot only READS it
	// (never recreates the singleton, seeded once by 0018); ResetDB
	// resets its counter via UPDATE below instead.
	"cover_art_provider_settings",
	// recsettings.New reconciles shipped defaults on every construction
	// (#1250), so truncating gives each test pristine tuning values.
	"recommendation_weight_profiles",
	"taste_tuning",
	"recommendation_tuning_audit",
	"tracks",
	"albums",
	"artists",
}

// ResetDB clears all data tables and removes any user whose username
// begins with TestUserPrefix. Users without that prefix (notably the
// operator's admin row) are left alone. Calls t.Fatalf on error.
func ResetDB(t *testing.T, pool *pgxpool.Pool) {
	t.Helper()
	ctx := context.Background()
	stmt := "TRUNCATE " + strings.Join(dataTables, ", ") + " RESTART IDENTITY CASCADE"
	if _, err := pool.Exec(ctx, stmt); err != nil {
		t.Fatalf("dbtest.ResetDB truncate: %v", err)
	}
	if _, err := pool.Exec(ctx,
		"DELETE FROM users WHERE username LIKE $1",
		TestUserPrefix+"%",
	); err != nil {
		t.Fatalf("dbtest.ResetDB delete test users: %v", err)
	}
	// Reset the monotonic cover-art source-version counter to its
	// post-migration seeded value. Truncating the row would break
	// SettingsService boot, which reads (never recreates) this
	// singleton; an UPDATE keeps the row while clearing cross-test
	// version accumulation (CurrentVersion=4 want 1, key-only-bump).
	if _, err := pool.Exec(ctx,
		"UPDATE cover_art_sources_meta SET current_version = 1",
	); err != nil {
		t.Fatalf("dbtest.ResetDB reset cover-art version: %v", err)
	}
}