package postgres

import (
	"fmt"
	"time"
	"gorm.io/gorm"
	"gorm.io/driver/postgres"
	"photography-backend/internal/config"
	"photography-backend/internal/models"
)

// Database 数据库连接
type Database struct {
	DB *gorm.DB
}

// NewDatabase 创建数据库连接
func NewDatabase(cfg *config.DatabaseConfig) (*Database, error) {
	dsn := fmt.Sprintf("host=%s port=%d user=%s password=%s dbname=%s sslmode=%s",
		cfg.Host,
		cfg.Port,
		cfg.Username,
		cfg.Password,
		cfg.Database,
		cfg.SSLMode,
	)
	
	db, err := gorm.Open(postgres.Open(dsn), &gorm.Config{})
	if err != nil {
		return nil, fmt.Errorf("failed to connect to database: %w", err)
	}
	
	// 获取底层sql.DB实例配置连接池
	sqlDB, err := db.DB()
	if err != nil {
		return nil, fmt.Errorf("failed to get sql.DB instance: %w", err)
	}
	
	// 设置连接池参数
	sqlDB.SetMaxOpenConns(cfg.MaxOpenConns)
	sqlDB.SetMaxIdleConns(cfg.MaxIdleConns)
	sqlDB.SetConnMaxLifetime(time.Duration(cfg.ConnMaxLifetime) * time.Second)
	
	// 测试连接
	if err := sqlDB.Ping(); err != nil {
		return nil, fmt.Errorf("failed to ping database: %w", err)
	}
	
	return &Database{DB: db}, nil
}

// AutoMigrate 自动迁移数据库表结构
func (d *Database) AutoMigrate() error {
	return d.DB.AutoMigrate(
		&models.User{},
		&models.Category{},
		&models.Tag{},
		&models.Photo{},
	)
}

// Close 关闭数据库连接
func (d *Database) Close() error {
	sqlDB, err := d.DB.DB()
	if err != nil {
		return err
	}
	return sqlDB.Close()
}

// Health 检查数据库健康状态
func (d *Database) Health() error {
	sqlDB, err := d.DB.DB()
	if err != nil {
		return err
	}
	return sqlDB.Ping()
}