package db

import (
	"context"
	"database/sql"
	"fmt"
	"io/fs"
	"path/filepath"
	"strings"
	"time"

	"golang.org/x/crypto/bcrypt"

	"github.com/benya/temporserv/internal/auth"
	"github.com/benya/temporserv/internal/config"
)

func Seed(ctx context.Context, database *sql.DB, cfg config.Config) error {
	if err := seedAdmin(ctx, database, cfg); err != nil {
		return err
	}

	if cfg.AppEnv == "development" && !hasMediaFiles(cfg.MediaRoot) {
		if err := seedLibrary(ctx, database); err != nil {
			return err
		}
	}

	return nil
}

func hasMediaFiles(root string) bool {
	found := false
	_ = filepath.WalkDir(root, func(path string, d fs.DirEntry, err error) error {
		if err != nil || d.IsDir() {
			return nil
		}

		switch strings.ToLower(filepath.Ext(path)) {
		case ".aac", ".flac", ".m4a", ".mp3", ".ogg", ".oga", ".opus", ".wav", ".wma":
			found = true
			return fs.SkipAll
		}

		return nil
	})
	return found
}

func seedAdmin(ctx context.Context, database *sql.DB, cfg config.Config) error {
	var count int
	if err := database.QueryRowContext(ctx, "SELECT COUNT(*) FROM users").Scan(&count); err != nil {
		return fmt.Errorf("count users: %w", err)
	}

	if count > 0 {
		return nil
	}

	passwordHash, err := bcrypt.GenerateFromPassword([]byte(cfg.DefaultAdminPassword), bcrypt.DefaultCost)
	if err != nil {
		return fmt.Errorf("hash admin password: %w", err)
	}
	subsonicSecret, err := auth.EncryptSubsonicSecret(cfg.DefaultAdminPassword, cfg.EncryptionKey)
	if err != nil {
		return fmt.Errorf("encrypt admin subsonic secret: %w", err)
	}

	now := time.Now().UTC().Format(time.RFC3339)

	_, err = database.ExecContext(
		ctx,
		`INSERT INTO users (id, username, password_hash, subsonic_auth_secret, is_admin, created_at, last_login_at)
		 VALUES (?, ?, ?, ?, 1, ?, ?)`,
		"user-admin",
		cfg.DefaultAdminUsername,
		string(passwordHash),
		subsonicSecret,
		now,
		now,
	)
	if err != nil {
		return fmt.Errorf("insert admin user: %w", err)
	}

	return nil
}

func seedLibrary(ctx context.Context, database *sql.DB) error {
	var artistCount int
	if err := database.QueryRowContext(ctx, "SELECT COUNT(*) FROM artists").Scan(&artistCount); err != nil {
		return fmt.Errorf("count artists: %w", err)
	}

	if artistCount > 0 {
		return nil
	}

	now := time.Now().UTC().Format(time.RFC3339)

	statements := []struct {
		query string
		args  []any
	}{
		{
			query: `INSERT INTO artists (id, name, sort_name, cover_art_id, created_at, updated_at) VALUES (?, ?, ?, ?, ?, ?)`,
			args:  []any{"artist-1", "Tycho", "Tycho", "", now, now},
		},
		{
			query: `INSERT INTO artists (id, name, sort_name, cover_art_id, created_at, updated_at) VALUES (?, ?, ?, ?, ?, ?)`,
			args:  []any{"artist-2", "Bonobo", "Bonobo", "", now, now},
		},
		{
			query: `INSERT INTO artists (id, name, sort_name, cover_art_id, created_at, updated_at) VALUES (?, ?, ?, ?, ?, ?)`,
			args:  []any{"artist-3", "Boards of Canada", "Boards of Canada", "", now, now},
		},
		{
			query: `INSERT INTO albums (id, artist_id, title, sort_title, year, genre, cover_art_id, created_at, updated_at) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)`,
			args:  []any{"album-1", "artist-1", "Awake", "Awake", 2014, "Electronic", "", now, now},
		},
		{
			query: `INSERT INTO albums (id, artist_id, title, sort_title, year, genre, cover_art_id, created_at, updated_at) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)`,
			args:  []any{"album-2", "artist-2", "Migration", "Migration", 2017, "Electronic", "", now, now},
		},
		{
			query: `INSERT INTO albums (id, artist_id, title, sort_title, year, genre, cover_art_id, created_at, updated_at) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)`,
			args:  []any{"album-3", "artist-3", "Tomorrow's Harvest", "Tomorrow's Harvest", 2013, "Electronic", "", now, now},
		},
		{
			query: `INSERT INTO tracks (id, album_id, artist_id, title, track_number, disc_number, duration_seconds, file_path, content_type, created_at, updated_at) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`,
			args:  []any{"track-1", "album-1", "artist-1", "Awake", 1, 1, 224, "demo/awake.mp3", "audio/mpeg", now, now},
		},
		{
			query: `INSERT INTO tracks (id, album_id, artist_id, title, track_number, disc_number, duration_seconds, file_path, content_type, created_at, updated_at) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`,
			args:  []any{"track-2", "album-2", "artist-2", "Migration", 1, 1, 301, "demo/migration.mp3", "audio/mpeg", now, now},
		},
		{
			query: `INSERT INTO tracks (id, album_id, artist_id, title, track_number, disc_number, duration_seconds, file_path, content_type, created_at, updated_at) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`,
			args:  []any{"track-3", "album-3", "artist-3", "Reach for the Dead", 1, 1, 292, "demo/reach-for-the-dead.mp3", "audio/mpeg", now, now},
		},
	}

	tx, err := database.BeginTx(ctx, nil)
	if err != nil {
		return fmt.Errorf("begin seed transaction: %w", err)
	}

	for _, statement := range statements {
		if _, err := tx.ExecContext(ctx, statement.query, statement.args...); err != nil {
			_ = tx.Rollback()
			return fmt.Errorf("seed statement failed: %w", err)
		}
	}

	if err := tx.Commit(); err != nil {
		return fmt.Errorf("commit seed transaction: %w", err)
	}

	return nil
}