package dal

import (
	"fmt"

	"gorm.io/driver/mysql"
	"gorm.io/gorm"
	"gorm.io/gorm/logger"
	"gorm.io/plugin/dbresolver"

	"gitea.micah.com/micah/standard/conf"
	"gitea.micah.com/micah/standard/internal/dal/query"
)

var DB *gorm.DB

func Init() {
	c := conf.GetConf()
	var err error
	loggerLevel := getLogLevel(c.MySQL.LogLevel)
	if loggerLevel < logger.Silent || loggerLevel > logger.Info {
		loggerLevel = logger.Info
	}

	DB, err = gorm.Open(mysql.Open(c.MySQL.DSN), &gorm.Config{
		SkipDefaultTransaction: true,
		PrepareStmt:            true,
		Logger:                 logger.Default.LogMode(loggerLevel),
	})
	if err != nil {
		panic(fmt.Sprintf("注册 DB DSN 失败, %+v", err))
	}
	if len(c.MySQL.ReplicasDSN) > 0 {
		dialects := make([]gorm.Dialector, len(c.MySQL.ReplicasDSN))
		for i, s := range c.MySQL.ReplicasDSN {
			dialects[i] = mysql.Open(s)
		}
		// 注册 DB Resolver 插件
		err = DB.Use(dbresolver.Register(dbresolver.Config{
			// 主库（写操作）
			Sources: []gorm.Dialector{mysql.Open(c.MySQL.DSN)},
			// 从库（读操作）
			Replicas: dialects,
			// 负载均衡策略（默认轮询）
			Policy: dbresolver.RandomPolicy{}, // 可选：随机、轮询、加权等
			// 自动检查连接健康
			TraceResolverMode: true, // 记录解析器日志
		}).SetMaxOpenConns(100))

		if err != nil {
			panic(fmt.Sprintf("注册 DB Resolver 失败, %+v", err))
		}
	}

	query.SetDefault(DB)
}

func getLogLevel(level string) logger.LogLevel {
	switch level {
	case "info":
		return logger.Info
	case "warn":
		return logger.Warn
	case "error":
		return logger.Error
	default:
		return logger.Silent

	}
}

func GetDB() *gorm.DB {
	return DB
}