package database

import (
	"fmt"
	"log"
	"sync"

	"git.x2erp.com/qdy/go-base/config"
	"git.x2erp.com/qdy/go-base/config/subconfigs"
	"git.x2erp.com/qdy/go-base/ctx"
	"git.x2erp.com/qdy/go-base/logger"
	"git.x2erp.com/qdy/go-base/model/response"
	"git.x2erp.com/qdy/go-db/driver"
	"git.x2erp.com/qdy/go-db/function"

	"github.com/jmoiron/sqlx"
)

// DBFactory 数据库工厂（全局单例模式）
type DBFactory struct {
	db     *sqlx.DB
	config *subconfigs.DatabaseConfig
}

var (
	instanceDB     *DBFactory
	instanceDBOnce sync.Once
	initErrDB      error
)

// CreateDBFactory 获取数据库工厂单例
func CreateDBFactory(cfg config.IConfig) *DBFactory {

	config := cfg.GetDatabaseConfig()
	instanceDBOnce.Do(func() {

		instanceDB, initErrDB = createDBFactoryNew(config)

	})

	if initErrDB != nil {
		log.Fatalf("DBFactory is error: '%v'", initErrDB)
	}

	return instanceDB
}

// createDBFactoryNew 获取数据库工厂单例
func createDBFactoryNew(config *subconfigs.DatabaseConfig) (*DBFactory, error) {

	if config == nil {
		log.Fatal("配置未初始化，请先在yaml进行配置")
	}

	if config.Type == "" {

		initErrDB = fmt.Errorf("database type must be configured")
		return nil, initErrDB
	}
	if config.Host == "" {
		initErrDB = fmt.Errorf("database host must be configured")
		return nil, initErrDB
	}
	if config.Database == "" {
		initErrDB = fmt.Errorf("database name must be configured")
		return nil, initErrDB
	}

	log.Printf("Creating database connection...")

	// 获取对应的驱动
	dbDriver, err := driver.Get(config.Type)
	if err != nil {
		initErrDB = fmt.Errorf("failed to get database driver: %v", err)
		return nil, initErrDB
	}

	// 将内部 DBConfig 转换为 drivers.DBConfig
	driverConfig := driver.DBConfig{
		Type:            config.Type,
		Host:            config.Host,
		Port:            config.Port,
		Username:        config.Username,
		Password:        config.Password,
		Database:        config.Database,
		MaxOpenConns:    config.MaxOpenConns,
		MaxIdleConns:    config.MaxIdleConns,
		ConnMaxLifetime: config.ConnMaxLifetime,
	}

	// 创建数据库连接
	db, err := dbDriver.Open(driverConfig)
	if err != nil {
		initErrDB = fmt.Errorf("failed to open database connection: %v", err)
		return nil, initErrDB
	}

	// 测试连接
	if err := function.TestConnection(db, config.Type); err != nil {
		db.Close()
		initErrDB = fmt.Errorf("database connection test failed: %v", err)
		return nil, initErrDB
	}

	log.Printf("DBFactory is successfully created.\n")

	instanceDB = &DBFactory{
		db:     db,
		config: config,
	}

	return instanceDB, initErrDB
}

// ========== DBFactory 实例方法 ==========

// GetDB 获取数据库连接
func (f *DBFactory) GetDB() *sqlx.DB {
	return f.db
}

func (f *DBFactory) GetName() string {
	return "DBFactory"
}

// Close 关闭数据库连接
func (f *DBFactory) Close() {
	if f.db != nil {
		err := f.db.Close()
		if err != nil {
			logger.Errorf("failed to close database connection: %v", err)
		}
		log.Printf("Database connection closed gracefully\n")
		f.db = nil
	}
}

// GetConfig 获取配置信息
func (f *DBFactory) GetConfig() subconfigs.DatabaseConfig {
	return *f.config
}

// TestConnection 测试连接
func (f *DBFactory) TestConnection() error {
	return function.TestConnection(f.db, f.config.Type)
}

// ========== 快捷操作方法 ==========

// QueryToJSON 快捷查询，直接返回 JSON 字节流
func (f *DBFactory) QueryToJSON(sql string, reqCtx *ctx.RequestContext) *response.QueryResult[[]map[string]interface{}] {
	return function.QueryToJSON(f.db, sql, reqCtx)
}

// QueryPositionalToJSON 位置参数查询并返回 JSON 字节数据
func (f *DBFactory) QueryPositionalToJSON(sql string, params []interface{}, reqCtx *ctx.RequestContext) *response.QueryResult[[]map[string]interface{}] {
	return function.QueryPositionalToJSON(f.db, sql, params, reqCtx)
}

// QueryParamsNameToJSON 命名参数查询并返回 JSON 字节数据
func (f *DBFactory) QueryParamsNameToJSON(sql string, params map[string]interface{}, reqCtx *ctx.RequestContext) *response.QueryResult[[]map[string]interface{}] {
	return function.QueryParamsNameToJSON(f.db, sql, params, reqCtx)
}

// QueryToCSV 快捷查询，直接返回 CSV 字符串（包含表头）
func (f *DBFactory) QueryToCSV(sql string, writerHeader bool, reqCtx *ctx.RequestContext) ([]byte, error) {
	return function.QueryToCSV(f.db, sql, writerHeader, reqCtx)
}

// QueryPositionalToCSV 位置参数查询并返回 CSV 字节数据
func (f *DBFactory) QueryPositionalToCSV(sql string, writerHeader bool, params []interface{}, reqCtx *ctx.RequestContext) ([]byte, error) {
	return function.QueryPositionalToCSV(f.db, sql, writerHeader, params, reqCtx)
}

// QueryParamsNameToCSV 命名参数查询并返回 CSV 字节数据
func (f *DBFactory) QueryParamsNameToCSV(sql string, writerHeader bool, params map[string]interface{}, reqCtx *ctx.RequestContext) ([]byte, error) {
	return function.QueryParamsNameToCSV(f.db, sql, writerHeader, params, reqCtx)
}

// ExecuteDDL 快捷执行DDL语句
func (f *DBFactory) ExecuteDDL(ddlSQL string) error {
	return function.ExecuteDDL(f.db, ddlSQL)
}

// ExecuteDDLWithTx 快捷在事务中执行DDL语句
func (f *DBFactory) ExecuteDDLWithTx(ddlSQL string) error {
	return function.ExecuteDDLWithTx(f.db, ddlSQL)
}

// ExecuteMultipleDDL 快捷执行多个DDL语句
func (f *DBFactory) ExecuteMultipleDDL(ddlSQLs []string) error {
	return function.ExecuteMultipleDDL(f.db, ddlSQLs)
}

// GetDBType 得到当前使用数据库类型
func (f *DBFactory) GetDBType() string {
	return f.config.Type
}

// GetDatabaseName 获取数据库名称
func (f *DBFactory) GetDatabaseName() string {
	return f.config.Database
}

// GetHost 获取数据库主机
func (f *DBFactory) GetHost() string {
	return f.config.Host
}

// GetPort 获取数据库端口
func (f *DBFactory) GetPort() int {
	return f.config.Port
}

// BeginTx 开始事务
func (f *DBFactory) BeginTx() (*sqlx.Tx, error) {
	return f.db.Beginx()
}

// GetStats 获取数据库连接统计信息
func (f *DBFactory) GetStats() interface{} {
	return f.db.Stats()
}

// Ping 测试数据库连接是否正常
func (f *DBFactory) Ping() error {
	return f.db.Ping()
}

// GetAvailableDrivers 获取可用的数据库驱动
func (f *DBFactory) GetAvailableDrivers() []string {
	return driver.GetAllDrivers()
}

// ========== 新增的简化操作方法 ==========

// QueryOne 查询单条记录
func (f *DBFactory) QueryOne(sql string, dest interface{}) error {
	return f.db.Get(dest, sql)
}

// QueryOneWithParams 带参数查询单条记录
func (f *DBFactory) QueryOneWithParams(sql string, dest interface{}, params ...interface{}) error {
	return f.db.Get(dest, sql, params...)
}

// QueryMany 查询多条记录
func (f *DBFactory) QueryMany(sql string, dest interface{}) error {
	return f.db.Select(dest, sql)
}

// QueryManyWithParams 带参数查询多条记录
func (f *DBFactory) QueryManyWithParams(sql string, dest interface{}, params ...interface{}) error {
	return f.db.Select(dest, sql, params...)
}

// Execute 执行更新操作
func (f *DBFactory) Execute(sql string) (int64, error) {
	result, err := f.db.Exec(sql)
	if err != nil {
		return 0, err
	}
	return result.RowsAffected()
}

// ExecuteWithParams 带参数执行更新操作
func (f *DBFactory) ExecuteWithParams(sql string, params ...interface{}) (int64, error) {
	result, err := f.db.Exec(sql, params...)
	if err != nil {
		return 0, err
	}
	return result.RowsAffected()
}

// QueryMap 查询单条记录到map
func (f *DBFactory) QueryMap(sql string) (map[string]interface{}, error) {
	result := make(map[string]interface{})
	err := f.db.QueryRowx(sql).MapScan(result)
	return result, err
}

// QueryMapWithParams 带参数查询单条记录到map
func (f *DBFactory) QueryMapWithParams(sql string, params ...interface{}) (map[string]interface{}, error) {
	result := make(map[string]interface{})
	err := f.db.QueryRowx(sql, params...).MapScan(result)
	return result, err
}

// QuerySliceMap 查询多条记录到map切片
func (f *DBFactory) QuerySliceMap(sql string) ([]map[string]interface{}, error) {
	rows, err := f.db.Queryx(sql)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var results []map[string]interface{}
	for rows.Next() {
		result := make(map[string]interface{})
		if err := rows.MapScan(result); err != nil {
			return nil, err
		}
		results = append(results, result)
	}
	return results, nil
}

// QuerySliceMapWithParams 带参数查询多条记录到map切片
func (f *DBFactory) QuerySliceMapWithParams(sql string, params ...interface{}) ([]map[string]interface{}, error) {
	rows, err := f.db.Queryx(sql, params...)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var results []map[string]interface{}
	for rows.Next() {
		result := make(map[string]interface{})
		if err := rows.MapScan(result); err != nil {
			return nil, err
		}
		results = append(results, result)
	}
	return results, nil
}