package wintergreen

import "image/color"
import "git.tebibyte.media/tomo/tomo"
import "golang.org/x/image/font/basicfont"
import "git.tebibyte.media/tomo/tomo/theme"
import "git.tebibyte.media/tomo/tomo/input"
import "git.tebibyte.media/tomo/tomo/event"

var colorFocus       = color.RGBA { R:  61, G: 128, B: 143, A: 255 }
var colorInput       = color.RGBA { R: 208, G: 203, B: 150, A: 255 }
var colorCarved      = color.RGBA { R: 151, G: 160, B: 150, A: 255 }
var colorShadow      = color.RGBA { R:  57, G:  59, B:  57, A: 255 }
var colorInputShadow = color.RGBA { R: 143, G: 146, B:  91, A: 255 }
var colorHighlight   = color.RGBA { R: 207, G: 215, B: 210, A: 255 }
var colorBackground  = color.RGBA { R: 169, G: 171, B: 168, A: 255 }
var colorForeground  = color.Black
var colorOutline     = color.Black

var outline = tomo.Border {
	Width: tomo.I(1),
	Color: [4]color.Color {
		colorOutline,
		colorOutline,
		colorOutline,
		colorOutline,
	},
}

var borderColorLifted   = [4]color.Color { colorShadow,      colorHighlight, colorHighlight, colorShadow }
var borderColorEngraved = [4]color.Color { colorHighlight,   colorShadow,    colorShadow,    colorHighlight }
var borderColorInput    = [4]color.Color { colorInputShadow, colorInput,     colorInput,     colorInputShadow }
var borderColorFocused  = [4]color.Color { colorFocus,       colorFocus,     colorFocus,     colorFocus }

type Theme struct { }

func (Theme) RGBA (id theme.Color) (r, g, b, a uint32) {
	switch id {
	case theme.ColorBackground: return colorBackground  .RGBA()
	case theme.ColorForeground: return colorForeground  .RGBA()
	case theme.ColorRaised:     return colorCarved      .RGBA()
	case theme.ColorSunken:     return colorCarved      .RGBA()
	case theme.ColorAccent:     return colorFocus       .RGBA()
	default:                    return color.Transparent.RGBA()
	}
}

func (Theme) Apply (object tomo.Object, role theme.Role) event.Cookie {
	box := object.Box()

	if textBox, ok := box.(tomo.TextBox); ok {
		textBox.SetDotColor(colorFocus)
		textBox.SetTextColor(colorForeground)
		textBox.SetFace(basicfont.Face7x13)
	}
	
	switch role.Object {
	case "Button":
		box.SetColor(colorCarved)
		mouseDown := false

		updateStyle := func () {
			border := []tomo.Border { outline, tomo.Border { } }
			switch {
			case mouseDown:
				border[1].Width = tomo.I(1, 0, 0, 1)
				border[1].Color = borderColorLifted
				box.SetPadding(tomo.I(9, 8, 8, 9))
			case box.Focused():
				border[1].Width = tomo.I(1)
				border[1].Color = borderColorFocused
				box.SetPadding(tomo.I(8))
			default:
				border[1].Width = tomo.I(1)
				border[1].Color = borderColorEngraved
				box.SetPadding(tomo.I(8))
			}	
			box.SetBorder(border...)
		}
		updateStyle()
		return event.MultiCookie (
			box.OnMouseDown(func (button input.Button) {
				if button != input.ButtonLeft { return }
				mouseDown = true
				updateStyle()
			}),
			box.OnMouseUp(func (button input.Button) {
				if button != input.ButtonLeft { return }
				mouseDown = false
				updateStyle()
			}),
			box.OnFocusEnter(updateStyle),
			box.OnFocusLeave(updateStyle))
		
	case "TextInput", "NumberInput":
		box.SetColor(colorInput)
		updateStyle := func () {
			border := []tomo.Border { outline, tomo.Border { } }
			switch {
			case box.Focused():
				border[1].Width = tomo.I(1)
				border[1].Color = borderColorFocused
				box.SetPadding(tomo.I(8))
			default:
				border[1].Width = tomo.I(1)
				border[1].Color = borderColorInput
				box.SetPadding(tomo.I(8))
			}
			box.SetBorder(border...)
		}
		updateStyle()
		return event.MultiCookie (
			box.OnFocusEnter(updateStyle),
			box.OnFocusLeave(updateStyle))
	default:
		box.SetColor(colorBackground)
		return event.MultiCookie()
	}
}