package utime

import (
	"database/sql/driver"
	"encoding/json"
	"fmt"
	"strings"
	"time"
)

type UnixTime struct {
	Utime int64
	Valid bool // Valid is true if Time is not NULL
}

func NewUnixTime(t time.Time) UnixTime {
	return UnixTime{
		Utime: t.Unix(),
		Valid: true,
	}
}

func (nt *UnixTime) Scan(value interface{}) error {
	var err error
	switch x := value.(type) {
	case time.Time:
		nt.Utime = x.Unix()
		fmt.Println("Unixtime.Scan: found time.Time ") // debug
	case []uint8:
		tmpTime, err := time.Parse(time.RFC3339, string(x))
		if err != nil {
			// try parsing with time.RFC3339nano
			tmpTime, err = time.Parse(time.RFC3339Nano, string(x))
			if err != nil {
				nt.Valid = false
				return nil
			}
		}
		nt.Utime = tmpTime.Unix()
		fmt.Println("Unixtime.Scan: tmptime: ", tmpTime) // debug
	case nil:
		fmt.Println("Unixtime.Scan: tmptime is nil") // debug
		nt.Valid = false
		return nil
	default:
		err = fmt.Errorf("null: cannot scan type %T into UnixTime: %v", value, value)
	}
	nt.Valid = err == nil
	return err
}

func (nt UnixTime) Value() (driver.Value, error) {
	if !nt.Valid {
		return nil, nil
	}
	return time.Unix(nt.Utime, 0), nil
}

func (nt *UnixTime) String() string {
	if !nt.Valid {
		return ""
	}
	return time.Unix(nt.Utime, 0).Format(time.RFC3339)
}

func (nt UnixTime) MarshalJSON() ([]byte, error) {
	return json.Marshal(strings.Replace(time.Unix(nt.Utime, 0).Format(time.RFC3339), "+", "Z", -1))
}

func (nt *UnixTime) UnmarshalJSON(b []byte) (err error) {
	if b[0] == '"' && b[len(b)-1] == '"' {
		b = b[1 : len(b)-1]
	}
	tmpTime, err := time.Parse(time.RFC3339, string(b))
	if err != nil {
		nt.Valid = false
		return err
	}
	nt.Valid = true
	nt.Utime = tmpTime.Unix()
	return
}