package component

import (
	"database/sql"
	"fmt"
	"gitea.party/public-messag-service/config"
	"github.com/urfave/cli/v2"
	"gorm.io/driver/mysql"
	"gorm.io/gorm"
	"gorm.io/gorm/schema"
	"gorm.io/plugin/dbresolver"
	"strings"
)

type MySQLClient struct {
	DB  *gorm.DB
	Cfg config.EntityMysql
	ref *MySQL
}

func (c *MySQLClient) Ref() *MySQL {
	return c.ref
}

func (c *MySQLClient) CliFlags(name string) []cli.Flag {
	return []cli.Flag{
		&cli.IntFlag{
			Name:   fmt.Sprintf("mysql-%s-open-limit", name),
			Usage:  fmt.Sprintf("mysql(%s) max open limit", name),
			Action: func(_ *cli.Context, v int) error { c.Cfg.MaxOpen = v; return nil },
		},
		&cli.IntFlag{
			Name:   fmt.Sprintf("mysql-%s-idle-limit", name),
			Usage:  fmt.Sprintf("mysql(%s) idle open limit", name),
			Action: func(_ *cli.Context, v int) error { c.Cfg.MaxIdle = v; return nil },
		},
		&cli.StringFlag{
			Name:  fmt.Sprintf("mysql-%s-dsn", name),
			Usage: fmt.Sprintf("mysql(%s) DSN (format: `{{user_name}}:{{password}}@tcp({{host}}:{{port}})/{{db_name}}?{{connect_options}}`)", name),
			Action: func(_ *cli.Context, val string) (err error) {
				dsn := strings.Split(val, ";")
				if err = c.Cfg.Master.ParserDSN(dsn[0]); err == nil {
					if len(dsn) > 1 {
						c.Cfg.Slave = make([]config.ConnectMysql, 0, len(dsn)-1)
						for i, l := 1, len(dsn); i < l; i++ {
							v := config.ConnectMysql{}
							if err = v.ParserDSN(dsn[i]); err != nil {
								break
							}
							c.Cfg.Slave = append(c.Cfg.Slave, v)
						}
					}
				}
				if err != nil {
					err = fmt.Errorf("Mysql DSN is invalid(%s)", err.Error())
				}
				return err
			},
		},
	}
}

func (c *MySQLClient) Init(env int, cc *MySQL) {
	c.ref = cc
}

func (c *MySQLClient) Config() *config.EntityMysql {
	return &c.Cfg
}

func (c *MySQLClient) Load(name string) (err error) {
	mastDB := mysql.Open(c.Cfg.Master.GetConnectDSN())
	gormDB, err := gorm.Open(mastDB, &gorm.Config{
		SkipDefaultTransaction: true,
		Logger:                 &c.ref.Log,
		NamingStrategy: schema.NamingStrategy{
			SingularTable: true,
		},
	})
	if err == nil {
		if len(c.Cfg.Slave) > 0 {
			slaveDBs := make([]gorm.Dialector, 0, len(c.Cfg.Slave))
			for k := range c.Cfg.Slave {
				slaveDBs = append(slaveDBs, mysql.Open(c.Cfg.Slave[k].GetConnectDSN()))
			}
			readWritePlugin := dbresolver.Register(dbresolver.Config{
				Sources:  []gorm.Dialector{mastDB},
				Replicas: slaveDBs,
				Policy:   dbresolver.RandomPolicy{},
			})
			readWritePlugin.SetMaxOpenConns(c.Cfg.MaxOpen)
			readWritePlugin.SetMaxIdleConns(c.Cfg.MaxIdle)
			err = gormDB.Use(readWritePlugin)
		} else {
			var sqlDB *sql.DB
			if sqlDB, err = gormDB.DB(); err == nil {
				sqlDB.SetMaxOpenConns(c.Cfg.MaxOpen)
				sqlDB.SetMaxIdleConns(c.Cfg.MaxIdle)
			}
		}
	}
	if err != nil {
		gormDB, err = nil, fmt.Errorf("Load Mysql (%s) Failed (Error: %s) ", name, err.Error())
	}
	c.DB = gormDB
	return err
}