extends Button
class_name LevelCard

## One map on the level select: its photograph, its name, and its mode.
##
## The cards used to be a two-stop gradient generated from `color1` and `color2`
## in the map's meta file. That tells a player which card they clicked last time
## and nothing at all about the map, which is the entire job of a level select —
## and the hover state was `use_hdr = true` on the gradient texture, which is not
## a visible change on any of them.
##
## The preview comes from assets/ui/map_previews/<folder>.png, shot by
## debug/map_preview_capture.gd from inside the map. A map with no preview falls
## back to its gradient, so nothing breaks for a map that has not been
## photographed yet.
##
## Built on Button rather than TextureButton so it gets focus, keyboard
## navigation and the theme's state machinery for free. The image sits inside the
## button's border rather than under it, so the border reads as a frame around a
## photograph instead of a rectangle behind one.

const INSET := 5

var _plate: ColorRect
var _label: Label
var _mode_label: Label


func setup(title: String, preview_path: String, gradient: Gradient,
		card_size: Vector2) -> void:
	custom_minimum_size = card_size
	clip_contents = true

	# The frame. Papaya at rest, volt on hover, and the fill stays transparent
	# so the photograph is what the player sees.
	var clear := Color(0, 0, 0, 0)
	add_theme_stylebox_override("normal", _frame(clear, UITheme.PAPAYA, 3))
	add_theme_stylebox_override("hover", _frame(clear, UITheme.VOLT, 5))
	add_theme_stylebox_override("pressed", _frame(
		Color(UITheme.VOLT.r, UITheme.VOLT.g, UITheme.VOLT.b, 0.25),
		UITheme.VOLT, 5))
	add_theme_stylebox_override("focus", _frame(clear, UITheme.CYAN, 5))
	add_theme_stylebox_override("disabled", _frame(
		Color(UITheme.INK.r, UITheme.INK.g, UITheme.INK.b, 0.7),
		UITheme.DEAD_EDGE, 3))

	if ResourceLoader.exists(preview_path):
		var shot := TextureRect.new()
		shot.texture = load(preview_path)
		shot.expand_mode = TextureRect.EXPAND_IGNORE_SIZE
		# COVERED, not scaled: a photograph letterboxed inside a card reads as a
		# thumbnail in a file browser. Filling the card and cropping reads as a
		# poster, which is what this is.
		shot.stretch_mode = TextureRect.STRETCH_KEEP_ASPECT_COVERED
		shot.mouse_filter = Control.MOUSE_FILTER_IGNORE
		_fill(shot)
		add_child(shot)
	else:
		var grad := TextureRect.new()
		var tex := GradientTexture2D.new()
		tex.gradient = gradient
		tex.width = int(card_size.x)
		tex.height = int(card_size.y)
		tex.fill_to = Vector2(1, 1)
		grad.texture = tex
		grad.expand_mode = TextureRect.EXPAND_IGNORE_SIZE
		grad.stretch_mode = TextureRect.STRETCH_SCALE
		grad.mouse_filter = Control.MOUSE_FILTER_IGNORE
		_fill(grad)
		add_child(grad)

	# The name plate: a hard ink band across the bottom rather than a gradient
	# fade, because the theme is drawn and a soft fade is not.
	_plate = ColorRect.new()
	_plate.color = Color(UITheme.INK.r, UITheme.INK.g, UITheme.INK.b, 0.88)
	_plate.mouse_filter = Control.MOUSE_FILTER_IGNORE
	_plate.set_anchors_and_offsets_preset(Control.PRESET_BOTTOM_WIDE)
	_plate.offset_top = -62
	_plate.offset_left = INSET
	_plate.offset_right = -INSET
	_plate.offset_bottom = -INSET
	add_child(_plate)

	var stack := VBoxContainer.new()
	stack.set_anchors_and_offsets_preset(Control.PRESET_FULL_RECT)
	stack.add_theme_constant_override("separation", -2)
	stack.mouse_filter = Control.MOUSE_FILTER_IGNORE
	_plate.add_child(stack)

	_label = Label.new()
	_label.text = title
	_label.add_theme_font_size_override("font_size", 28)
	_label.add_theme_color_override("font_color", UITheme.PAPER)
	_label.add_theme_color_override("font_outline_color", UITheme.INK)
	_label.add_theme_constant_override("outline_size", 6)
	_label.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
	stack.add_child(_label)

	_mode_label = Label.new()
	_mode_label.add_theme_font_size_override("font_size", 16)
	_mode_label.add_theme_color_override("font_color", UITheme.PAPER_DIM)
	_mode_label.add_theme_color_override("font_outline_color", UITheme.INK)
	_mode_label.add_theme_constant_override("outline_size", 4)
	_mode_label.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
	stack.add_child(_mode_label)

	# The label follows the frame, same rule as every other control: hover turns
	# the frame volt, so the name turns volt with it.
	mouse_entered.connect(func(): _tint(UITheme.VOLT))
	mouse_exited.connect(func(): _tint(UITheme.PAPER))
	focus_entered.connect(func(): _tint(UITheme.CYAN))
	focus_exited.connect(func(): _tint(UITheme.PAPER))


## What pressing this card will start. Shown under the name so the player is
## never guessing which mode the button they are about to press launches.
func set_mode_text(text: String) -> void:
	if _mode_label:
		_mode_label.text = text


func _tint(c: Color) -> void:
	if _label:
		_label.add_theme_color_override("font_color", c)


func _fill(c: Control) -> void:
	c.set_anchors_and_offsets_preset(Control.PRESET_FULL_RECT)
	c.offset_left = INSET
	c.offset_top = INSET
	c.offset_right = -INSET
	c.offset_bottom = -INSET


func _frame(fill: Color, border: Color, width: int) -> StyleBoxFlat:
	var sb := StyleBoxFlat.new()
	sb.bg_color = fill
	sb.border_color = border
	sb.set_border_width_all(width)
	sb.set_corner_radius_all(5)
	sb.shadow_color = Color(UITheme.INK.r, UITheme.INK.g, UITheme.INK.b, 0.6)
	sb.shadow_size = 4
	sb.shadow_offset = Vector2(5, 5)
	return sb