package database

import (
	"log"
	"os"
	"strconv"
	"strings"
	"time"

	"gorm.io/driver/mysql"
	"gorm.io/driver/postgres"
	"gorm.io/driver/sqlite"
	"gorm.io/driver/sqlserver"
	"gorm.io/gorm"
	"gorm.io/gorm/logger"
)

type Credentials struct {
	Host        string
	Port        int
	Dialect     string
	Database    string
	Table       string
	User        string
	Password    string
	Socket      string
	MaxOpenConn int
	MaxIdleConn int
	MaxLifeTime int
	Debug       bool
}

func (c *Credentials) getDSN() gorm.Dialector {
	switch strings.ToLower(c.Dialect) {
	case "mysql":
		if c.Socket != "" {
			dsn := c.User +
				":" + c.Password +
				"@unix(" + c.Socket +
				")/" + c.Database +
				"?charset=utf8mb4&collation=utf8mb4_unicode_ci&readTimeout=10s&writeTimeout=30s&timeout=5s&parseTime=True&loc=UTC&time_zone=%27%2B00%3A00%27"
			return mysql.Open(dsn)
		}
		dsn := c.User +
			":" + c.Password +
			"@tcp(" + c.Host +
			":" + strconv.Itoa(c.Port) +
			")/" + c.Database +
			"?charset=utf8mb4&collation=utf8mb4_unicode_ci&readTimeout=30s&writeTimeout=30s&timeout=5s&parseTime=True&loc=UTC&time_zone=%27%2B00%3A00%27"
		return mysql.Open(dsn)
	case "mssql":
		dsn := "sqlserver://" + c.User +
			":" + c.Password + "@" +
			c.Host + ":" +
			strconv.Itoa(c.Port) + "?database=" + c.Database + "&connection+timeout=5;SelectMethod=Cursor;integratedSecurity=true;"
		return sqlserver.Open(dsn)
	case "postgres":
		dsn := "host=" + c.Host +
			" port=" + strconv.Itoa(c.Port) +
			" user=" + c.User +
			" dbname=" + c.Database +
			" password=" + c.Password +
			" sslmode=disable connect_timeout=5"
		return postgres.Open(dsn)
	case "sqlite":
		return sqlite.Open("gorm.db")
		// return sqlite.Open("file::memory:?cache=shared")
	}
	return nil
}

func Connect(c Credentials) (*gorm.DB, error) {
	newLogger := logger.New(
		log.New(os.Stdout, "\r\n", log.LstdFlags), // io writer
		logger.Config{
			SlowThreshold: time.Second, // Slow SQL threshold
			LogLevel:      logger.Info, // Log level
			Colorful:      true,        // Disable color
		},
	)
	config := gorm.Config{Logger: newLogger}
	if strings.EqualFold(c.Dialect, "sqlite") {
		// FIXME HACK for sqlite
		config.DisableForeignKeyConstraintWhenMigrating = true
	}
	db, err := gorm.Open(c.getDSN(), &config)
	if err != nil {
		return nil, err
	}
	return db, nil
	// sqlDB, err := db.DB()
	// sqlDB.SetMaxOpenConns(config.Configuration.DBMaxOpenConn)
	// sqlDB.SetMaxIdleConns(config.Configuration.DBMaxIdleConn)
	// sqlDB.SetConnMaxLifetime(time.Duration(config.Configuration.DBMaxLifeTime) * time.Second)
}