go-timertxt/sort.go

104 lines
2.5 KiB
Go

package timertxt
import (
"errors"
"sort"
"time"
)
// Flags for defining sort element and order.
const (
SortUnfinishedStart = iota
SortStartDateAsc
SortStartDateDesc
SortFinishDateAsc
SortFinishDateDesc
SortError
)
// Sort allows a TimerList to be sorted by certain predefined fields.
// See constants Sort* for fields and sort order.
func (timerlist *TimerList) Sort(sortFlag int) error {
switch sortFlag {
case SortUnfinishedStart:
timerlist.sortByUnfinishedThenStart()
case SortStartDateAsc, SortStartDateDesc:
timerlist.sortByStartDate(sortFlag)
case SortFinishDateAsc, SortFinishDateDesc:
timerlist.sortByFinishDate(sortFlag)
default:
return errors.New("Unrecognized sort option")
}
timerlist.SortFlag = sortFlag
return nil
}
func (timerlist *TimerList) refresh() {
timerlist.Sort(timerlist.SortFlag)
}
type timerlistSort struct {
timerlists TimerList
by func(t1, t2 *Timer) bool
}
func (ts *timerlistSort) Len() int {
return len(ts.timerlists.Timers)
}
func (ts *timerlistSort) Swap(l, r int) {
ts.timerlists.Timers[l], ts.timerlists.Timers[r] = ts.timerlists.Timers[r], ts.timerlists.Timers[l]
}
func (ts *timerlistSort) Less(l, r int) bool {
return ts.by(ts.timerlists.Timers[l], ts.timerlists.Timers[r])
}
func (timerlist *TimerList) sortBy(by func(t1, t2 *Timer) bool) *TimerList {
ts := &timerlistSort{
timerlists: *timerlist,
by: by,
}
sort.Sort(ts)
return timerlist
}
func sortByDate(asc bool, date1, date2 time.Time) bool {
if asc { // ASC
if !date1.IsZero() && !date2.IsZero() {
return date1.Before(date2)
}
return !date2.IsZero()
}
// DESC
if !date1.IsZero() && !date2.IsZero() {
return date1.After(date2)
}
return date2.IsZero()
}
func (timerlist *TimerList) sortByStartDate(order int) *TimerList {
timerlist.sortBy(func(t1, t2 *Timer) bool {
return sortByDate(order == SortStartDateAsc, t1.StartDate, t2.StartDate)
})
return timerlist
}
func (timerlist *TimerList) sortByFinishDate(order int) *TimerList {
timerlist.sortBy(func(t1, t2 *Timer) bool {
return sortByDate(order == SortFinishDateAsc, t1.FinishDate, t2.FinishDate)
})
return timerlist
}
func (timerlist *TimerList) sortByUnfinishedThenStart() *TimerList {
timerlist.sortBy(func(t1, t2 *Timer) bool {
if t1.FinishDate.IsZero() && !t2.FinishDate.IsZero() {
return true
} else if t2.FinishDate.IsZero() && !t1.FinishDate.IsZero() {
return false
}
return sortByDate(false, t1.StartDate, t2.StartDate)
})
return timerlist
}