package storage

import (
	"encoding/json"
	"fmt"
	"go-desk/internal/crypto"
	"go-desk/internal/dbclient"
	"go-desk/internal/storage/models"

	"gorm.io/gorm"
)

// ConnectionService 连接管理服务
type ConnectionService struct {
	db *gorm.DB
}

// NewConnectionService 创建连接服务
func NewConnectionService() (*ConnectionService, error) {
	db := GetDB()
	if db == nil {
		// 尝试重新初始化
		var err error
		db, err = Init()
		if err != nil {
			return nil, fmt.Errorf("数据库初始化失败: %v", err)
		}
	}
	return &ConnectionService{db: db}, nil
}

// SaveConnection 保存连接配置
func (s *ConnectionService) SaveConnection(conn *models.DbConnection) error {
	if conn.Name == "" {
		return fmt.Errorf("连接名称不能为空")
	}
	if conn.Type == "" {
		return fmt.Errorf("数据库类型不能为空")
	}
	if conn.Host == "" {
		return fmt.Errorf("主机地址不能为空")
	}

	// 检查名称是否重复（排除当前记录）
	var count int64
	query := s.db.Model(&models.DbConnection{}).Where("name = ?", conn.Name)
	if conn.ID > 0 {
		query = query.Where("id != ?", conn.ID)
	}
	query.Count(&count)
	if count > 0 {
		return fmt.Errorf("连接名称已存在")
	}

	if conn.ID > 0 {
		// 更新模式
		updateData := map[string]interface{}{
			"name":     conn.Name,
			"type":     conn.Type,
			"host":     conn.Host,
			"port":     conn.Port,
			"username": conn.Username,
			"database": conn.Database,
			"options":  conn.Options,
		}

		// 如果提供了新密码，加密后更新
		if conn.Password != "" {
			encrypted, err := crypto.EncryptPassword(conn.Password)
			if err != nil {
				return fmt.Errorf("密码加密失败: %v", err)
			}
			updateData["password"] = encrypted
		}
		// 如果密码为空，不更新密码字段（保留原密码）

		return s.db.Model(&models.DbConnection{}).Where("id = ?", conn.ID).Updates(updateData).Error
	}

	// 新增模式 - 必须提供密码
	if conn.Password == "" {
		return fmt.Errorf("新增连接时密码不能为空")
	}

	// 加密密码
	encrypted, err := crypto.EncryptPassword(conn.Password)
	if err != nil {
		return fmt.Errorf("密码加密失败: %v", err)
	}
	conn.Password = encrypted

	return s.db.Create(conn).Error
}

// ListConnections 获取连接列表
func (s *ConnectionService) ListConnections() ([]models.DbConnection, error) {
	var connections []models.DbConnection
	err := s.db.Order("created_at DESC").Find(&connections).Error
	return connections, err
}

// GetConnection 获取连接详情
func (s *ConnectionService) GetConnection(id uint) (*models.DbConnection, error) {
	var conn models.DbConnection
	err := s.db.First(&conn, id).Error
	if err != nil {
		return nil, err
	}
	return &conn, nil
}

// DeleteConnection 删除连接配置
func (s *ConnectionService) DeleteConnection(id uint) error {
	return s.db.Delete(&models.DbConnection{}, id).Error
}

// TestConnection 测试连接（需要根据类型调用不同的测试方法）
func (s *ConnectionService) TestConnection(conn *models.DbConnection) error {
	// 解密密码用于测试
	password, err := crypto.DecryptPassword(conn.Password)
	if err != nil {
		return fmt.Errorf("密码解密失败: %v", err)
	}

	// 根据类型测试连接
	switch conn.Type {
	case "mysql":
		return testMySQLConnection(conn.Host, conn.Port, conn.Username, password, conn.Database)
	case "redis":
		return testRedisConnection(conn.Host, conn.Port, password)
	case "mongo":
		// 解析 Options 获取 MongoDB 连接参数
		authSource := ""
		authMechanism := ""
		if conn.Options != "" {
			var opts map[string]interface{}
			if err := json.Unmarshal([]byte(conn.Options), &opts); err == nil {
				if as, ok := opts["authSource"].(string); ok && as != "" {
					authSource = as
				}
				if am, ok := opts["authMechanism"].(string); ok && am != "" {
					authMechanism = am
				}
			}
		}
		return testMongoConnection(conn.Host, conn.Port, conn.Username, password, conn.Database, authSource, authMechanism)
	default:
		return fmt.Errorf("不支持的数据库类型: %s", conn.Type)
	}
}

// testMySQLConnection 测试 MySQL 连接
func testMySQLConnection(host string, port int, username, password, database string) error {
	return dbclient.TestMySQLConnection(host, port, username, password, database)
}

// testRedisConnection 测试 Redis 连接
func testRedisConnection(host string, port int, password string) error {
	return dbclient.TestRedisConnection(host, port, password)
}

// testMongoConnection 测试 MongoDB 连接
func testMongoConnection(host string, port int, username, password, database, authSource, authMechanism string) error {
	return dbclient.TestMongoConnectionWithOptions(host, port, username, password, database, authSource, authMechanism)
}