package dao

import (
	"fmt"
	"time"

	"github.com/gin-gonic/gin"
	"github.com/jinzhu/gorm"
	_ "github.com/jinzhu/gorm/dialects/mysql"
	_ "github.com/jinzhu/gorm/dialects/sqlite"
	"github.com/spf13/viper"

	"zendea/model"
	"zendea/util/log"
)

var (
	db *gorm.DB
)

const DRIVER_MYSQL = "mysql"
const DRIVER_SQLITE = "sqlite"

// Setup : Connect to mysql database
func Setup() {
	var err error

	switch viper.Get("database.driver") {
	case DRIVER_SQLITE:
		path := viper.GetString("database.sqlite.path")
		db, err = gorm.Open("sqlite3", path)
		if err != nil {
			log.Fatal(fmt.Sprintf("Failed to connect sqlite %s", err.Error()))
		} else {
			log.Info("Successfully connect to sqlite3, path: %s.", path)
			db.LogMode(true)
		}
	case DRIVER_MYSQL:
		host := viper.GetString("database.mysql.host")
		user := viper.GetString("database.mysql.user")
		password := viper.GetString("database.mysql.password")
		name := viper.GetString("database.mysql.name")
		charset := viper.GetString("database.mysql.charset")

		dsn := fmt.Sprintf("%s:%s@tcp(%s)/%s?charset=%s&parseTime=True&loc=Local", user, password, host, name, charset)
		db, err = gorm.Open("mysql", dsn)
		if err != nil {
			log.Fatal(fmt.Sprintf("Failed to connect mysql %s", err.Error()))
		} else {
			log.Info("Successfully connect to MySQL, database: %s.", name)
			db.DB().SetMaxIdleConns(viper.GetInt("database.mysql.pool.min"))
			db.DB().SetMaxOpenConns(viper.GetInt("database.mysql.pool.max"))
			db.DB().SetConnMaxLifetime(time.Minute)
			if gin.Mode() != gin.ReleaseMode {
				db.LogMode(true)
			}
		}
	default:
		log.Fatal("We do not support this kind of storage system yet!")
	}

	db.SingularTable(true) //禁用表名复数
	if err = db.AutoMigrate(model.Models...).Error; nil != err {
		log.Error("auto migrate tables failed")
	}
}

// Shutdown - close database connection
func Shutdown() error {
	log.Info("Closing database's connections")
	return db.Close()
}

// GetDb - get a database connection
func DB() *gorm.DB {
	return db
}

// 事务环绕
func Tx(txFunc func(tx *gorm.DB) error) (err error) {
	tx := db.Begin()
	if tx.Error != nil {
		return
	}

	defer func() {
		if r := recover(); r != nil {
			tx.Rollback()
			panic(r) // re-throw panic after Rollback
		} else if err != nil {
			tx.Rollback()
		} else {
			err = tx.Commit().Error
		}
	}()

	err = txFunc(tx)
	return err
}