package ui

import (
	"image/color"
	"time"

	"github.com/hajimehoshi/ebiten/v2"
)

var (
	TIMERBAR_DEFAULT_BACKGROUND = color.Black
	TIMERBAR_DEFAULT_FOREGROUND = color.White
)

type TimerBar struct {
	WidgetBase
	fg       color.Color
	bg       color.Color
	start    time.Time
	deadline time.Time
}

func NewTimerBar(x, y int, width, height int, timer time.Duration) *TimerBar {
	tb := &TimerBar{
		WidgetBase: NewWidgetBase(x, y, width, height),
		bg:         TEXTBOX_DEFAULT_BACKGROUND,
		fg:         TEXTBOX_DEFAULT_FOREGROUND,
		start:      time.Now(),
		deadline:   time.Now().Add(timer),
	}
	tb.renderImpl = func() *ebiten.Image { return tb.render() }
	tb.EventHandlersMap["update"] = func() error {
		if time.Now().Before(tb.deadline) {
			tb.ForceRedraw()
		}
		return nil
	}
	return tb
}

func (tb *TimerBar) Bg(bg color.Color) *TimerBar {
	tb.bg = bg
	return tb
}

func (tb *TimerBar) Fg(fg color.Color) *TimerBar {
	tb.fg = fg
	return tb
}

func (tb *TimerBar) render() *ebiten.Image {
	img := ebiten.NewImage(tb.Width, tb.Height)
	img.Fill(tb.bg)
	fraction := float64(time.Since(tb.start)) / float64(tb.deadline.Sub(tb.start))
	barWidth := int(float64(tb.Width) * fraction)
	if barWidth == 0 {
		barWidth = 1
	}
	bar := ebiten.NewImage(barWidth, tb.Height)
	bar.Fill(tb.fg)
	op := ebiten.DrawImageOptions{}
	img.DrawImage(bar, &op)
	return img
}