package tools

import (
	"time"

	dp "github.com/markusmobius/go-dateparser"
	"github.com/markusmobius/go-dateparser/date"
)

const (
	day = time.Hour * 24
)

// These are somewhat arbitrary, but reasonably useful min and max times
var (
	MinTime = time.Unix(-2208988800, 0) // Jan 1, 1900
	MaxTime = MinTime.Add(1<<63 - 1)
)

func ParseDate(in string) (t time.Time, err error) {
	if in == "min" {
		return MinTime, nil
	}
	if in == "max" {
		return MaxTime, nil
	}

	d, err := dp.Parse(nil, in)
	if err != nil {
		return
	}
	t = d.Time.Local()
	trunc := time.Second
	switch d.Period {
	case date.Minute:
		trunc = time.Minute
	case date.Hour:
		trunc = time.Hour
	case date.Day:
		trunc = day
		// @todo Handle other cases separately
	}
	t = t.Truncate(trunc)
	return
}