package ui

import (
	"bytes"
	"fmt"
	"image/color"
	"log"

	"github.com/ebitenui/ebitenui/image"
	"github.com/ebitenui/ebitenui/widget"
	"github.com/hajimehoshi/ebiten/v2/text/v2"
	"golang.org/x/image/colornames"
	"golang.org/x/image/font/gofont/goregular"
)

func Root() *widget.Container {
	face, err := loadFont(12)
	if err != nil {
		panic(err)
	}

	slidersTrack := &widget.SliderTrackImage{
		Idle:  image.NewNineSliceColor(color.NRGBA{100, 100, 100, 255}),
		Hover: image.NewNineSliceColor(color.NRGBA{100, 100, 100, 255}),
	}

	slidersButton := &widget.ButtonImage{
		Idle:    image.NewNineSliceColor(color.NRGBA{255, 100, 100, 255}),
		Hover:   image.NewNineSliceColor(color.NRGBA{255, 100, 100, 255}),
		Pressed: image.NewNineSliceColor(color.NRGBA{255, 100, 100, 255}),
	}

	root := widget.NewContainer(
		widget.ContainerOpts.Layout(widget.NewAnchorLayout()),
	)

	topLeft := widget.NewContainer(
		// widget.ContainerOpts.BackgroundImage(
		// 	image.NewNineSliceColor(colornames.Indigo),
		// ),
		widget.ContainerOpts.Layout(widget.NewRowLayout(
			widget.RowLayoutOpts.Direction(widget.DirectionVertical),
			widget.RowLayoutOpts.Spacing(5),
			widget.RowLayoutOpts.Padding(widget.NewInsetsSimple(5)),
		)),
		widget.ContainerOpts.WidgetOpts(
			widget.WidgetOpts.LayoutData(widget.AnchorLayoutData{
				VerticalPosition:   widget.AnchorLayoutPositionStart,
				HorizontalPosition: widget.AnchorLayoutPositionStart,
				StretchVertical:    true,
			}),
			widget.WidgetOpts.MinSize(80, 50),
		),
	)

	root.AddChild(topLeft)

	overPopLabel := widget.NewText(
		widget.TextOpts.Text(fmt.Sprintf("Over Population Threshold: >%d", 5), &face, color.White),
		widget.TextOpts.Position(widget.TextPositionStart, widget.TextPositionCenter),
		widget.TextOpts.WidgetOpts(
			widget.WidgetOpts.LayoutData(widget.RowLayoutData{
				Position: widget.RowLayoutPositionCenter,
			}),
		),
	)

	topLeft.AddChild(overPopLabel)

	overPopSlider := widget.NewSlider(
		// Set the slider orientation - n/s vs e/w
		widget.SliderOpts.Orientation(widget.DirectionHorizontal),
		// Set the minimum and maximum value for the slider
		widget.SliderOpts.MinMax(0, 6),
		// Set the current value of the slider, without triggering a change event
		widget.SliderOpts.InitialCurrent(5),
		widget.SliderOpts.WidgetOpts(
			// Set the Widget to layout in the center on the screen
			widget.WidgetOpts.LayoutData(widget.AnchorLayoutData{
				HorizontalPosition: widget.AnchorLayoutPositionCenter,
				VerticalPosition:   widget.AnchorLayoutPositionCenter,
			}),
			// Set the widget's dimensions
			widget.WidgetOpts.MinSize(100, 6),
		),
		widget.SliderOpts.Images(
			slidersTrack,
			slidersButton,
		),
		// Set the size of the handle
		widget.SliderOpts.FixedHandleSize(6),
		// Set the offset to display the track
		widget.SliderOpts.TrackOffset(0),
		// Set the size to move the handle
		widget.SliderOpts.PageSizeFunc(func() int {
			return 1
		}),
	)
	topLeft.AddChild(overPopSlider)

	underPopLabel := widget.NewText(
		widget.TextOpts.Text(fmt.Sprintf("Under Population Threshold: <%d", 5), &face, color.White),
		widget.TextOpts.Position(widget.TextPositionStart, widget.TextPositionCenter),
		widget.TextOpts.WidgetOpts(
			widget.WidgetOpts.LayoutData(widget.RowLayoutData{
				Position: widget.RowLayoutPositionCenter,
			}),
		),
	)

	topLeft.AddChild(underPopLabel)

	underPopSlider := widget.NewSlider(
		// Set the slider orientation - n/s vs e/w
		widget.SliderOpts.Orientation(widget.DirectionHorizontal),
		// Set the minimum and maximum value for the slider
		widget.SliderOpts.MinMax(0, 6),
		// Set the current value of the slider, without triggering a change event
		widget.SliderOpts.InitialCurrent(2),
		widget.SliderOpts.WidgetOpts(
			// Set the Widget to layout in the center on the screen
			widget.WidgetOpts.LayoutData(widget.AnchorLayoutData{
				HorizontalPosition: widget.AnchorLayoutPositionCenter,
				VerticalPosition:   widget.AnchorLayoutPositionCenter,
			}),
			// Set the widget's dimensions
			widget.WidgetOpts.MinSize(100, 6),
		),
		widget.SliderOpts.Images(
			slidersTrack,
			slidersButton,
		),
		// Set the size of the handle
		widget.SliderOpts.FixedHandleSize(6),
		// Set the offset to display the track
		widget.SliderOpts.TrackOffset(0),
		// Set the size to move the handle
		widget.SliderOpts.PageSizeFunc(func() int {
			return 1
		}),
		// Set the callback to call when the slider value is changed
		widget.SliderOpts.ChangedHandler(func(args *widget.SliderChangedEventArgs) {
			if args.Current == 0 {
				underPopLabel.Label = "Under Population Threshold: (disabled)"
			} else {
				underPopLabel.Label = fmt.Sprintf("Under Population Threshold: <%d", args.Current)
			}
			if args.Current > overPopSlider.Current {
				overPopSlider.Current = args.Current
			}
			_ = EventBus().Emit(SliderEvent{data: args, name: UnderPopulationSliderEvent})
		}),
	)

	overPopSlider.ChangedEvent.AddHandler(func(argsRaw any) {
		args, ok := argsRaw.(*widget.SliderChangedEventArgs)
		if !ok {
			return
		}

		if args.Current == 6 {
			overPopLabel.Label = "Over Population Threshold: (disabled)"
		} else {
			overPopLabel.Label = fmt.Sprintf("Over Population Threshold: >%d ", args.Current)
		}

		if args.Current < underPopSlider.Current {
			underPopSlider.Current = args.Current
		}
		_ = EventBus().Emit(SliderEvent{data: args, name: OverPopulationSliderEvent})
	})

	topLeft.AddChild(underPopSlider)

	reprodTartgeLabel := widget.NewText(
		widget.TextOpts.Text(fmt.Sprintf("Reproduction Target: =%d", 2), &face, color.White),
		widget.TextOpts.Position(widget.TextPositionCenter, widget.TextPositionCenter),
		widget.TextOpts.WidgetOpts(
			widget.WidgetOpts.LayoutData(widget.RowLayoutData{
				Position: widget.RowLayoutPositionStart,
			}),
		),
	)

	topLeft.AddChild(reprodTartgeLabel)

	reprodTargetSlider := widget.NewSlider(
		// Set the slider orientation - n/s vs e/w
		widget.SliderOpts.Orientation(widget.DirectionHorizontal),
		// Set the minimum and maximum value for the slider
		widget.SliderOpts.MinMax(0, 6),
		// Set the current value of the slider, without triggering a change event
		widget.SliderOpts.InitialCurrent(2),
		widget.SliderOpts.WidgetOpts(
			// Set the Widget to layout in the center on the screen
			widget.WidgetOpts.LayoutData(widget.AnchorLayoutData{
				HorizontalPosition: widget.AnchorLayoutPositionStart,
				VerticalPosition:   widget.AnchorLayoutPositionCenter,
			}),
			// Set the widget's dimensions
			widget.WidgetOpts.MinSize(100, 6),
		),
		widget.SliderOpts.Images(
			slidersTrack,
			slidersButton,
		),
		// Set the size of the handle
		widget.SliderOpts.FixedHandleSize(6),
		// Set the offset to display the track
		//
		widget.SliderOpts.TrackOffset(0),
		// Set the size to move the handle
		widget.SliderOpts.PageSizeFunc(func() int {
			return 1
		}),
		// Set the callback to call when the slider value is changed
		widget.SliderOpts.ChangedHandler(func(args *widget.SliderChangedEventArgs) {
			if args.Current > overPopSlider.Current || args.Current < underPopSlider.Current {
				reprodTartgeLabel.Label = "Reproduction target: (disabled due to other parameters)"
			} else {
				reprodTartgeLabel.Label = fmt.Sprintf("Reproduction target: =%d", args.Current)
			}
			_ = EventBus().Emit(SliderEvent{data: args, name: ReproductionTargetEvent})
		}),
	)

	topLeft.AddChild(reprodTargetSlider)

	bottomRight := widget.NewContainer(
		widget.ContainerOpts.Layout(widget.NewRowLayout(
			widget.RowLayoutOpts.Direction(widget.DirectionVertical),
			widget.RowLayoutOpts.Spacing(5),
			widget.RowLayoutOpts.Padding(widget.NewInsetsSimple(5)),
		)),
		widget.ContainerOpts.WidgetOpts(
			widget.WidgetOpts.LayoutData(widget.AnchorLayoutData{
				VerticalPosition:   widget.AnchorLayoutPositionEnd,
				HorizontalPosition: widget.AnchorLayoutPositionEnd,
			}),
			widget.WidgetOpts.MinSize(80, 50),
		),
	)

	root.AddChild(bottomRight)

	speedLabel := widget.NewText(
		widget.TextOpts.Text("Speed: 0 ticks/second", &face, color.White),
		widget.TextOpts.Position(widget.TextPositionStart, widget.TextPositionCenter),
		widget.TextOpts.WidgetOpts(
			widget.WidgetOpts.LayoutData(widget.RowLayoutData{
				Position: widget.RowLayoutPositionCenter,
			}),
		),
	)

	bottomRight.AddChild(speedLabel)

	speedSlider := widget.NewSlider(
		// Set the slider orientation - n/s vs e/w
		widget.SliderOpts.Orientation(widget.DirectionHorizontal),
		// Set the minimum and maximum value for the slider
		widget.SliderOpts.MinMax(0, 10),
		// Set the current value of the slider, without triggering a change event
		widget.SliderOpts.InitialCurrent(1),
		widget.SliderOpts.WidgetOpts(
			// Set the Widget to layout in the center on the screen
			widget.WidgetOpts.LayoutData(widget.AnchorLayoutData{
				HorizontalPosition: widget.AnchorLayoutPositionCenter,
				VerticalPosition:   widget.AnchorLayoutPositionCenter,
			}),
			// Set the widget's dimensions
			widget.WidgetOpts.MinSize(100, 6),
		),
		widget.SliderOpts.Images(
			slidersTrack,
			slidersButton,
		),
		// Set the size of the handle
		widget.SliderOpts.FixedHandleSize(6),
		// Set the offset to display the track
		widget.SliderOpts.TrackOffset(0),
		// Set the size to move the handle
		widget.SliderOpts.PageSizeFunc(func() int {
			return 1
		}),
		// Set the callback to call when the slider value is changed
		widget.SliderOpts.ChangedHandler(func(args *widget.SliderChangedEventArgs) {
			speedLabel.Label = fmt.Sprintf("Speed: %d ticks/second", args.Current)
			_ = EventBus().Emit(SliderEvent{data: args, name: SpeedSliderEvent})
		}),
	)

	bottomRight.AddChild(speedSlider)

	baseColor := colornames.Aliceblue
	resetButton := widget.NewButton(
		widget.ButtonOpts.Image(&widget.ButtonImage{
			Idle:    image.NewBorderedNineSliceColor(baseColor, colornames.Black, 1),
			Hover:   image.NewBorderedNineSliceColor(mixColors(baseColor, colornames.Gainsboro, 0.2), colornames.Black, 1),
			Pressed: image.NewBorderedNineSliceColor(mixColors(baseColor, colornames.Darkgray, 0.2), colornames.Black, 1),
		}),
		widget.ButtonOpts.Text("Reset", &face, &widget.ButtonTextColor{
			Idle: colornames.Purple,
		}),
		widget.ButtonOpts.WidgetOpts(
			widget.WidgetOpts.LayoutData(widget.RowLayoutData{
				Stretch: true,
			}),
		),
		widget.ButtonOpts.TextPosition(
			widget.TextPositionCenter,
			widget.TextPositionCenter,
		),
		widget.ButtonOpts.ClickedHandler(func(args *widget.ButtonClickedEventArgs) {
			_ = EventBus().Emit(ButtonEvent{data: args, name: ResetButtonEvent})
		}),
	)

	bottomRight.AddChild(resetButton)

	return root
}

type SliderEvent struct {
	name string
	data *widget.SliderChangedEventArgs
}

// Data implements Event.
func (s SliderEvent) Data() any {
	return s.data
}

// Name implements Event.
func (s SliderEvent) Name() string {
	return s.name
}

type ButtonEvent struct {
	name string
	data *widget.ButtonClickedEventArgs
}

// Data implements Event.
func (b ButtonEvent) Data() any {
	return b.data
}

// Name implements Event.
func (b ButtonEvent) Name() string {
	return b.name
}

func loadFont(size float64) (text.Face, error) {
	s, err := text.NewGoTextFaceSource(bytes.NewReader(goregular.TTF))
	if err != nil {
		log.Fatal(err)
		return nil, err
	}

	return &text.GoTextFace{
		Source: s,
		Size:   size,
	}, nil
}