package uiwidget

import (
	"math"
	"time"

	"fyne.io/fyne/v2"
	"fyne.io/fyne/v2/theme"
	"fyne.io/fyne/v2/widget"

	xwidget "fyne.io/x/fyne/widget"
)

type DateEntry struct {
	widget.Entry
	calendar *xwidget.Calendar
	popUp    *widget.PopUp

	OnDateChanged func(time.Time)

	date time.Time
}

func NewDateEntry() *DateEntry {
	e := &DateEntry{}
	e.Validator = func(s string) error {
		_, err := time.Parse("02/01/2006", s)
		return err
	}
	e.OnChanged = func(s string) {
		if e.Validate() != nil {
			if e.OnDateChanged != nil {
				time, _ := time.Parse("02/01/2006", s)
				e.OnDateChanged(time)
			}
		}
	}
	e.ExtendBaseWidget(e)
	e.SetDate(time.Now())
	return e
}

func (e *DateEntry) CreateRenderer() fyne.WidgetRenderer {
	e.ExtendBaseWidget(e)
	if e.ActionItem == nil {
		e.ActionItem = e.setupDropdown()
		if e.Disabled() {
			e.ActionItem.(fyne.Disableable).Disable()
		}
	}
	return e.Entry.CreateRenderer()
}

func (e *DateEntry) Enable() {
	if e.ActionItem != nil {
		e.ActionItem.(fyne.Disableable).Enable()
	}
	e.Entry.Enable()
}

func (e *DateEntry) Disable() {
	if e.ActionItem != nil {
		e.ActionItem.(fyne.Disableable).Disable()
	}
	e.Entry.Disable()
}

func (e *DateEntry) MinSize() fyne.Size {
	e.ExtendBaseWidget(e)
	return e.Entry.MinSize()
}

func (e *DateEntry) Move(pos fyne.Position) {
	e.Entry.Move(pos)
	if e.popUp != nil {
		e.popUp.Move(e.popUpPos())
	}
}

func (e *DateEntry) Resize(size fyne.Size) {
	e.Entry.Resize(size)
	if e.popUp != nil {
		e.popUp.Resize(fyne.NewSize(size.Width, e.popUp.Size().Height))
	}
}

func (e *DateEntry) SetDate(date time.Time) {
	e.date = date
	e.calendar = xwidget.NewCalendar(date, e.onDateSelected)
	e.SetText(date.Format("02/01/2006"))

	if e.ActionItem == nil {
		e.ActionItem = e.setupDropdown()
		if e.Disabled() {
			e.ActionItem.(fyne.Disableable).Disable()
		}
	}
}

func (e *DateEntry) GetDate() time.Time {
	return e.date
}

func (e *DateEntry) popUpPos() fyne.Position {
	entryPos := fyne.CurrentApp().Driver().AbsolutePositionForObject(e)
	return entryPos.Add(fyne.NewPos(0, e.Size().Height-theme.InputBorderSize()))
}

func (e *DateEntry) setupDropdown() *widget.Button {
	dropdownButton := widget.NewButton("", func() {
		c := fyne.CurrentApp().Driver().CanvasForObject(e)

		e.popUp = widget.NewPopUp(e.calendar, c)
		e.popUp.ShowAtPosition(e.popUpPos())
		e.popUp.Resize(
			fyne.NewSize(
				float32(math.Max(float64(e.Size().Width), float64(e.popUp.MinSize().Width))),
				e.popUp.MinSize().Height))
	})
	dropdownButton.Importance = widget.LowImportance
	dropdownButton.SetIcon(theme.MenuDropDownIcon())
	return dropdownButton
}

func (e *DateEntry) onDateSelected(date time.Time) {
	e.date = date
	e.SetText(e.date.Format("02/01/2006"))
	if e.popUp != nil {
		e.popUp.Hide()
	}
}