package main

import (
	"errors"
	"fmt"
	"strconv"
	"time"

	"git.bullercodeworks.com/brian/gime"
)

// filterTimerCollection takes a collection and a function that it runs every entry through
// If the function returns true for the entry, it adds it to a new collection to be returned
func filterTimerCollection(c *gime.TimeEntryCollection, fn func(t *gime.TimeEntry) bool) *gime.TimeEntryCollection {
	ret := new(gime.TimeEntryCollection)
	for i := 0; i < c.Length(); i++ {
		if fn(c.Get(i)) {
			ret.Push(c.Get(i))
		}
	}
	return ret
}

func TimerCollectionToString(c *gime.TimeEntryCollection) string {
	var ret string
	for i := 0; i < c.Length(); i++ {
		ret += TimerToString(c.Get(i))
		if i < c.Length()-1 {
			ret += "\n"
		}
	}
	return ret
}

// TimerToString takes a TimeEntry and gives a nicely formatted string
func TimerToString(t *gime.TimeEntry) string {
	var ret string
	var end string
	if t.StartsToday() {
		ret = t.GetStart().Format("15:04 - ")
		end = "**:**"
	} else {
		ret = t.GetStart().Format("2006/01/02 15:04:05 - ")
		end = "**:**:**"
	}
	if !t.GetEnd().IsZero() {
		if t.EndsToday() {
			end = t.GetEnd().Format("15:04")
		} else {
			end = t.GetEnd().Format("2006/01/02 15:04:05")
		}
	}
	ret += end
	tags := t.GetTags()
	if tags.Length() > 0 {
		ret += " [ "
		for i := 0; i < tags.Length(); i++ {
			ret += tags.Get(i) + " "
		}
		ret += "]"
	}
	return ret
}

func InferTimerDetailString(t *gime.TimeEntry) string {
	diffEnd := time.Now()
	if !t.GetEnd().IsZero() {
		diffEnd = t.GetEnd()
	}
	if int(diffEnd.Sub(t.GetStart())) >= (int(time.Hour) * diffEnd.Hour()) {
		return TimerDetailToLongString(t)
	}
	return TimerDetailToString(t)
}

func TimerDetailToString(t *gime.TimeEntry) string {
	ret := t.GetStart().Format("15:04")
	if t.GetEnd().IsZero() {
		ret += " (" + padLeft(sinceToString(t.GetStart()), len("00h 00m 00s")) + ") "
	} else {
		ret += " (" + padLeft(diffToString(t.GetStart(), t.GetEnd()), len("00h 00m 00s")) + ") "
	}
	if t.GetTags().Length() > 0 {
		ret += " [ "
		for j := 0; j < t.GetTags().Length(); j++ {
			ret += t.GetTags().Get(j)
			if j < t.GetTags().Length()-1 {
				ret += ", "
			}
		}
		ret += " ] "
	}
	return ret
}

// ...ToLongString includes year/month/day
func TimerDetailToLongString(t *gime.TimeEntry) string {
	ret := t.GetStart().Format(time.Stamp)
	if t.GetEnd().IsZero() {
		ret += " (" + padLeft(sinceToString(t.GetStart()), len("0000y 00m 00d 00h 00m 00s")) + ") "
	} else {
		ret += " (" + padLeft(diffToString(t.GetStart(), t.GetEnd()), len("0000y 00m 00d 00h 00m 00s")) + ") "
	}
	if t.GetTags().Length() > 0 {
		ret += " [ "
		for j := 0; j < t.GetTags().Length(); j++ {
			ret += t.GetTags().Get(j)
			if j < t.GetTags().Length()-1 {
				ret += ", "
			}
		}
		ret += " ] "
	}
	return ret
}

// findTimerById takes a timer id and returns the TimeEntry and the type string
// of the entry corresponding to that id
// It searches TypeCurrent -> TypeRecent -> TypeArchive
func findTimerById(tmrId int) (*gime.TimeEntry, int, error) {
	// Find the timer for this tmrId
	var prevNum, numLoaded int
	for i := range gdb.AllTypes {
		timeCollection := gdb.LoadTimeEntryCollection(gdb.AllTypes[i])
		numLoaded += timeCollection.Length()
		if numLoaded > tmrId {
			// This is the set that it's in, the index we need is tmrId - prevNum
			return timeCollection.Get(tmrId - prevNum), gdb.AllTypes[i], nil
		}
		prevNum = numLoaded
	}
	return nil, gime.TypeAll, errors.New("Unable to find timer with id: " + strconv.Itoa(tmrId))
}

func parseFuzzyTime(t string) (time.Time, error) {
	var ret time.Time
	var err error
	for i := range fuzzyFormats {
		ret, err = time.Parse(fuzzyFormats[i], t)
		if err == nil {
			// Make sure it's in the local timezone
			tz := time.Now().Format("Z07:00")
			t = ret.Format("2006-01-02T15:04:05") + tz
			if ret, err = time.Parse(time.RFC3339, t); err != nil {
				return ret, err
			}
			// Check for zero on year/mo/day
			if ret.Year() == 0 && ret.Month() == time.January && ret.Day() == 1 {
				ret = ret.AddDate(time.Now().Year(), int(time.Now().Month())-1, time.Now().Day()-1)
			}
			return ret, nil
		}
	}
	return time.Time{}, errors.New("Unable to parse time: " + t)
}

func sinceToString(tm time.Time) string {
	return diffToString(tm, time.Now())
}

func diffToString(tm1, tm2 time.Time) string {
	ret := ""
	yr, mo, dy, hr, mn, sc := diff(tm1, tm2)
	higher := false

	if yr > 0 {
		ret += fmt.Sprintf("%4dy ", yr)
		higher = true
	}
	if mo > 0 || higher {
		ret += fmt.Sprintf("%2dm ", mo)
		higher = true
	}
	if dy > 0 || higher {
		ret += fmt.Sprintf("%2dd ", dy)
		higher = true
	}
	if hr > 0 || higher {
		ret += fmt.Sprintf("%2dh ", hr)
		higher = true
	}
	if mn > 0 || higher {
		ret += fmt.Sprintf("%2dm ", mn)
		higher = true
	}
	if sc > 0 || higher {
		ret += fmt.Sprintf("%2ds", sc)
	}
	return ret
}

func padRight(st string, l int) string {
	for len(st) < l {
		st = st + " "
	}
	return st
}

func padLeft(st string, l int) string {
	for len(st) < l {
		st = " " + st
	}
	return st
}

func diff(a, b time.Time) (year, month, day, hour, min, sec int) {
	if a.Location() != b.Location() {
		b = b.In(a.Location())
	}
	if a.After(b) {
		a, b = b, a
	}
	y1, M1, d1 := a.Date()
	y2, M2, d2 := b.Date()

	h1, m1, s1 := a.Clock()
	h2, m2, s2 := b.Clock()

	year = int(y2 - y1)
	month = int(M2 - M1)
	day = int(d2 - d1)
	hour = int(h2 - h1)
	min = int(m2 - m1)
	sec = int(s2 - s1)

	// Normalize negative values
	if sec < 0 {
		sec += 60
		min--
	}
	if min < 0 {
		min += 60
		hour--
	}
	if hour < 0 {
		hour += 24
		day--
	}
	if day < 0 {
		// days in month:
		t := time.Date(y1, M1, 32, 0, 0, 0, 0, time.UTC)
		day += 32 - t.Day()
		month--
	}
	if month < 0 {
		month += 12
		year--
	}

	return
}