package store

import (
	"fmt"
	"log"
	"os"
	"path/filepath"
	"opencatd-open/pkg/config"

	_ "github.com/lib/pq"
	"github.com/ncruces/go-sqlite3/gormlite"
	"gorm.io/driver/mysql"
	"gorm.io/driver/postgres"
	"gorm.io/gorm"
)

var DB *gorm.DB

func InitDB(cfg *config.Config) (*gorm.DB, error) {
	var (
		dialector gorm.Dialector
		err       error
	)

	switch cfg.DB_Type {
	case "sqlite":
		dialector, err = sqliteDialector(cfg.DSN)
		if err != nil {
			return nil, err
		}
	case "postgres":
		dialector = postgresDialector(cfg.DSN)
	case "mysql":
		dialector = mysqlDialector(cfg.DSN)
	default:
		return nil, fmt.Errorf("unsupported database type: %s", cfg.DB_Type)
	}

	db, err := gorm.Open(dialector, &gorm.Config{})
	if err != nil {
		return nil, fmt.Errorf("failed to connect database: %w", err)
	}

	sqlDB, err := db.DB()
	if err != nil {
		return nil, fmt.Errorf("failed to get underlying *sql.DB: %w", err)
	}
	sqlDB.SetMaxOpenConns(cfg.DBMaxOpenConns)
	sqlDB.SetMaxIdleConns(cfg.DBMaxIdleConns)

	if err := db.AutoMigrate(AllModels()...); err != nil {
		log.Printf("AutoMigrate warning: %v", err)
	}

	DB = db
	return db, nil
}

func sqliteDialector(dsn string) (gorm.Dialector, error) {
	if dsn == "" {
		dsn = "db/openteam.db"
	}
	// sqlite 不会自动创建上级目录，先确保它存在（与 docker-compose 挂载的 /app/db 对应）
	if dir := filepath.Dir(dsn); dir != "." && dir != string(filepath.Separator) {
		if err := os.MkdirAll(dir, 0o755); err != nil {
			return nil, fmt.Errorf("failed to create database directory %s: %w", dir, err)
		}
	}
	return gormlite.Open(dsn), nil
}

func postgresDialector(dsn string) gorm.Dialector {
	if dsn == "" {
		dsn = "host=localhost user=postgres password=postgres dbname=opencatd port=5432 sslmode=disable"
	}
	return postgres.Open(dsn)
}

func mysqlDialector(dsn string) gorm.Dialector {
	if dsn == "" {
		dsn = "root:password@tcp(127.0.0.1:3306)/opencatd?charset=utf8mb4&parseTime=True&loc=Local"
	}
	return mysql.Open(dsn)
}