package components

import (
	"image"

	"gioui.org/layout"
	"gioui.org/unit"
	"gioui.org/widget"
	"gioui.org/widget/material"
)

type ButtonState int

const (
	NormalButton ButtonState = iota
	SelectedButton
	UnselectedButton
)

type iconAndTextButton struct {
	theme  *material.Theme
	button *widget.Clickable
	icon   *widget.Icon
	word   string
	axis   layout.Axis
	state  ButtonState
}

func (b iconAndTextButton) Layout(gtx layout.Context) layout.Dimensions {
	btn := material.ButtonLayout(b.theme, b.button)
	switch b.state {
	case NormalButton:
		btn.Background = b.theme.Palette.Bg
	case SelectedButton:
		btn.Background = b.theme.Palette.ContrastBg
	case UnselectedButton:
		btn.Background = b.theme.Palette.Bg
	}

	return btn.Layout(gtx, func(gtx layout.Context) layout.Dimensions {
		return layout.UniformInset(unit.Dp(12)).Layout(gtx, func(gtx layout.Context) layout.Dimensions {
			iconAndLabel := layout.Flex{Axis: b.axis, Alignment: layout.Middle}
			var bottomSpacer, textIconSpacer unit.Dp

			if b.axis == layout.Horizontal {
				bottomSpacer = unit.Dp(0)
				textIconSpacer = unit.Dp(2)
			} else {
				bottomSpacer = unit.Dp(2)
				textIconSpacer = unit.Dp(0)
			}

			layIcon := layout.Rigid(func(gtx layout.Context) layout.Dimensions {
				return layout.Inset{Bottom: bottomSpacer, Right: textIconSpacer}.Layout(gtx, func(gtx layout.Context) layout.Dimensions {
					var d layout.Dimensions
					if b.icon != nil {
						size := gtx.Dp(unit.Dp(24))

						if b.axis == layout.Horizontal {
							size = gtx.Dp(unit.Dp(56)) - 2*gtx.Dp(unit.Dp(16))
						}

						gtx.Constraints = layout.Exact(image.Pt(size, size))
						if b.state == SelectedButton {
							d = b.icon.Layout(gtx, b.theme.Palette.ContrastFg)
						} else {
							d = b.icon.Layout(gtx, b.theme.Palette.Fg)
						}
					}
					return d
				})
			})

			layLabel := layout.Rigid(func(gtx layout.Context) layout.Dimensions {
				return layout.Inset{Top: bottomSpacer, Right: textIconSpacer}.Layout(gtx, func(gtx layout.Context) layout.Dimensions {
					l := material.Body1(b.theme, b.word)
					if b.state == SelectedButton {
						l.Color = b.theme.Palette.ContrastFg
					} else {
						l.Color = b.theme.Palette.Fg
					}
					return l.Layout(gtx)
				})
			})

			return iconAndLabel.Layout(gtx, layIcon, layLabel)
		})
	})
}