package xztime

import (
	"database/sql/driver"
	"fmt"
	sysTime "time"
)

type Time struct {
	sysTime.Time
	layout string
}

var TimeLayout = "2006-01-02 15:04:05"

// 在使用 json.Marshal 时触发
func (t Time) MarshalJSON() ([]byte, error) {
	if t.layout == "" {
		return []byte(fmt.Sprintf(`"%s"`, t.Format(TimeLayout))), nil
	} else {
		return []byte(fmt.Sprintf(`"%s"`, t.Format(t.layout))), nil
	}
}

// 在使用 json.Unmarshal 时触发
func (t *Time) UnmarshalJSON(data []byte) error {
	st, err := sysTime.Parse(`"`+TimeLayout+`"`, string(data))
	if err != nil {
		return err
	}
	*t = Time{Time: st}
	return nil
}

func (t Time) Value() (driver.Value, error) {
	var zeroTime sysTime.Time
	if t.Time.UnixNano() == zeroTime.UnixNano() {
		return nil, nil
	}
	return t.Time, nil
}

func (t *Time) Scan(v interface{}) error {
	value, ok := v.(sysTime.Time)
	if ok {
		*t = Time{Time: value}
		return nil
	}
	return fmt.Errorf("can not convert %v to timestamp", v)
}

// fmt.Printf 触发
func (t *Time) String() string {
	if t.layout == "" {
		return fmt.Sprintf(`"%s"`, t.Format(TimeLayout))
	} else {
		return fmt.Sprintf(`"%s"`, t.Format(t.layout))
	}
}

// 当前时间
func Now() Time {
	return Time{Time: sysTime.Now()}
}

// 根据字符解析时间
func Parse(layout, value string) (time Time, err error) {
	t, err := sysTime.Parse(layout, value)
	if err != nil {
		return
	}
	time.Time = t
	return
}