package database

import (
	"fmt"
	"gorm.io/driver/mysql"
	"gorm.io/driver/postgres"
	"gorm.io/driver/sqlite"
	"gorm.io/gorm"
	"gorm.io/gorm/logger"
	"log"
	"os"
	"time"
)

type Config struct {
	Driver   string `json:"driver"`   // mysql, postgres, sqlite
	Host     string `json:"host,optional"`
	Port     int    `json:"port,optional"`
	Username string `json:"username,optional"`
	Password string `json:"password,optional"`
	Database string `json:"database,optional"`
	Charset  string `json:"charset,optional"`
	SSLMode  string `json:"ssl_mode,optional"`
	FilePath string `json:"file_path,optional"` // for sqlite
}

func NewDB(config Config) (*gorm.DB, error) {
	var db *gorm.DB
	var err error
	
	// 配置日志
	newLogger := logger.New(
		log.New(os.Stdout, "\r\n", log.LstdFlags), // io writer
		logger.Config{
			SlowThreshold: time.Second,   // 慢 SQL 阈值
			LogLevel:      logger.Silent, // 日志级别
			Colorful:      false,         // 禁用彩色打印
		},
	)
	
	switch config.Driver {
	case "mysql":
		dsn := fmt.Sprintf("%s:%s@tcp(%s:%d)/%s?charset=%s&parseTime=True&loc=Local",
			config.Username, config.Password, config.Host, config.Port, config.Database, config.Charset)
		db, err = gorm.Open(mysql.Open(dsn), &gorm.Config{
			Logger: newLogger,
		})
	case "postgres":
		dsn := fmt.Sprintf("host=%s user=%s password=%s dbname=%s port=%d sslmode=%s TimeZone=Asia/Shanghai",
			config.Host, config.Username, config.Password, config.Database, config.Port, config.SSLMode)
		db, err = gorm.Open(postgres.Open(dsn), &gorm.Config{
			Logger: newLogger,
		})
	case "sqlite":
		db, err = gorm.Open(sqlite.Open(config.FilePath), &gorm.Config{
			Logger: newLogger,
		})
	default:
		return nil, fmt.Errorf("unsupported database driver: %s", config.Driver)
	}
	
	if err != nil {
		return nil, err
	}
	
	// 设置连接池
	sqlDB, err := db.DB()
	if err != nil {
		return nil, err
	}
	
	sqlDB.SetMaxIdleConns(10)
	sqlDB.SetMaxOpenConns(100)
	sqlDB.SetConnMaxLifetime(time.Hour)
	
	return db, nil
}