package models

import (
	"encoding/json"
	"fmt"
	"github.com/jinzhu/gorm"
	_ "github.com/jinzhu/gorm/dialects/mysql"
	"github.com/patrickmn/go-cache"
	"io/ioutil"
	"kefu/common"
	"kefu/tools"
	"kefu/types"
	"log"
	"reflect"
	"strings"
	"time"
)

var DB *gorm.DB
var DBcache *cache.Cache

type Model struct {
	ID        uint      `gorm:"primary_key" json:"id"`
	CreatedAt time.Time `json:"created_at"`
	UpdatedAt time.Time `json:"updated_at"`
}

func NewConnect(mysqlConfigFile string) error {
	var mysql = &types.Mysql{
		Username: "go_fly_pro",
		Password: "go_fly_pro",
		Database: "go_fly_pro",
		Server:   "127.0.0.1",
		Port:     "3306",
	}
	isExist, _ := tools.IsFileExist(mysqlConfigFile)
	if !isExist {
		panic("MYSQL配置文件不存在!" + mysqlConfigFile)
	}
	info, err := ioutil.ReadFile(mysqlConfigFile)
	if err != nil {
		panic("MYSQL配置文件读取失败!" + err.Error())
	}
	err = json.Unmarshal(info, mysql)
	if err != nil {
		panic("解析MYSQL配置文件JSON结构失败!" + err.Error())
	}
	dsn := fmt.Sprintf("%s:%s@tcp(%s:%s)/%s?charset=utf8mb4&parseTime=True&loc=Local", mysql.Username, mysql.Password, mysql.Server, mysql.Port, mysql.Database)
	DB, err = gorm.Open("mysql", dsn)
	if err != nil {
		log.Println("数据库连接失败:", err)
		//panic("数据库连接失败!")
		return err
	}
	DB.SingularTable(true)
	DB.LogMode(true)
	DB.DB().SetMaxIdleConns(10)
	DB.DB().SetMaxOpenConns(100)
	DB.DB().SetConnMaxLifetime(59 * time.Second)
	//初始化配置数据
	InitConfig()
	DBcache = cache.New(5*time.Minute, 10*time.Minute)
	return nil
}

func Execute(sql string) error {
	db := DB.Exec(sql)
	err := db.Error
	if err != nil {
		log.Println("models.go sql execute error:" + err.Error())
		return err
	}
	return nil
}
func CloseDB() {
	defer DB.Close()
}

//重连数据库
func CheckModels() {
	if common.MySQLConnectFaild {
		err := NewConnect(common.ConfigDirPath + "/mysql.json")
		if err == nil {
			common.MySQLConnectFaild = false
		}
	}
}
func BatchInsert(db *gorm.DB, data interface{}, batchSize int) error {
	value := reflect.ValueOf(data)
	if value.Kind() != reflect.Slice {
		return fmt.Errorf("BatchInsert: input data type is not slice")
	}

	length := value.Len()
	if length == 0 {
		return nil
	}

	tx := db.Begin()
	if tx.Error != nil {
		return tx.Error
	}

	//modelType := value.Index(0).Type()
	tableName := tx.NewScope(data).TableName()

	fields := make([]string, 0, len(tx.NewScope(data).Fields()))
	for _, field := range tx.NewScope(data).Fields() {
		if !field.IsPrimaryKey && !field.IsIgnored {
			fields = append(fields, field.DBName)
		}
	}

	//placeholders := make([]string, 0, len(fields))
	//for _, _ = range fields {
	//	placeholders = append(placeholders, "?")
	//}
	//placeholderStr := "(" + strings.Join(placeholders, ",") + ")"

	var query strings.Builder
	query.WriteString(fmt.Sprintf("INSERT INTO %s (%s) VALUES ", tableName, strings.Join(fields, ",")))

	var args []interface{}
	for i := 0; i < length/batchSize; i++ {
		start := i * batchSize
		end := (i + 1) * batchSize
		if end > length {
			end = length
		}

		values := make([]string, 0, batchSize)
		for j := start; j < end; j++ {
			var valueStrings []string
			for _, field := range fields {
				valueStrings = append(valueStrings, "?")
				args = append(args, value.FieldByName(field).Interface())
			}
			values = append(values, "("+strings.Join(valueStrings, ",")+")")
		}

		if _, err := query.WriteString(strings.Join(values, ",")); err != nil {
			tx.Rollback()
			return err
		}

		if i < length/batchSize-1 {
			query.WriteString(",")
		}
	}

	if length%batchSize > 0 {
		values := make([]string, 0, length%batchSize)
		for i := length - length%batchSize; i < length; i++ {
			var valueStrings []string
			for _, field := range fields {
				valueStrings = append(valueStrings, "?")
				args = append(args, value.FieldByName(field).Interface())
			}
			values = append(values, "("+strings.Join(valueStrings, ",")+")")
		}

		if _, err := query.WriteString(strings.Join(values, ",")); err != nil {
			tx.Rollback()
			return err
		}
	}

	if db := tx.Exec(query.String(), args...); db.Error != nil {
		tx.Rollback()
		return db.Error
	}

	return tx.Commit().Error
}