class_name ResourceTransferList
extends Control

# Two-sided cargo control. Resources are rows and locations stay fixed:
# fleet on the left, the current building on the right. Horizontal arrows
# make the result of a press visible before the player commits to it.

signal transfer_requested(resource_type: String, to_building: bool, amount: int)

const HEADER_HEIGHT: float = 66.0
const FLEET_COLOR: Color = Color(1.0, 0.78, 0.25)
const LOCAL_COLOR: Color = Color(0.45, 0.9, 0.55)
const RULE_COLOR: Color = Color(0.18, 0.38, 0.52)
const ALL_AMOUNT: int = 1 << 30
const AMOUNT_OPTIONS: Array[int] = [1, 5, 25, ALL_AMOUNT]

var building_id: int = 0
var extractor_index: int = -1
var _destination_heading: Label
var _rows: Dictionary = {}


func _ready() -> void:
	var fleet_heading := _make_label("FLEET HOLD", 26, FLEET_COLOR)
	fleet_heading.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
	add_child(fleet_heading)
	_destination_heading = _make_label("THIS BUILDING", 26, LOCAL_COLOR)
	_destination_heading.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
	add_child(_destination_heading)

	for resource_type in GameState.resource_types():
		var colour: Color = GameState.resource_color(resource_type)
		var glyph := ResourceGlyph.new()
		glyph.resource_type = resource_type
		add_child(glyph)
		var name_label := _make_label(GameState.resource_name(resource_type).to_upper(), 29, colour)
		name_label.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
		add_child(name_label)
		var fleet_amount := _make_label("0", 48, FLEET_COLOR)
		fleet_amount.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
		add_child(fleet_amount)
		var local_amount := _make_label("0", 48, LOCAL_COLOR)
		local_amount.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
		add_child(local_amount)

		var unload := IconButton.new()
		unload.name = "%sToBuildingButton" % GameState.resource_name(resource_type)
		unload.icon = IconButton.Icon.RIGHT_ARROW
		unload.glow_color = colour
		unload.pressed.connect(_request_transfer.bind(resource_type, true))
		add_child(unload)
		var unload_label := _make_label("UNLOAD  →", 23, colour)
		unload_label.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
		add_child(unload_label)

		var load := IconButton.new()
		load.name = "%sToFleetButton" % GameState.resource_name(resource_type)
		load.icon = IconButton.Icon.LEFT_ARROW
		load.glow_color = colour
		load.pressed.connect(_request_transfer.bind(resource_type, false))
		add_child(load)
		var load_label := _make_label("←  LOAD", 23, colour)
		load_label.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
		add_child(load_label)

		var decrease := IconButton.new()
		decrease.name = "%sDecreaseButton" % GameState.resource_name(resource_type)
		decrease.icon = IconButton.Icon.MINUS
		decrease.glow_color = colour
		decrease.pressed.connect(_change_amount.bind(resource_type, -1))
		add_child(decrease)
		var amount_label := _make_label("ALL", 28, colour)
		amount_label.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
		add_child(amount_label)
		var increase := IconButton.new()
		increase.name = "%sIncreaseButton" % GameState.resource_name(resource_type)
		increase.icon = IconButton.Icon.PLUS
		increase.glow_color = colour
		increase.pressed.connect(_change_amount.bind(resource_type, 1))
		add_child(increase)
		var amount_caption := _make_label("AMOUNT", 18, Color(0.62, 0.78, 0.86))
		amount_caption.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
		add_child(amount_caption)

		_rows[resource_type] = {
			"glyph": glyph, "name": name_label,
			"fleet_amount": fleet_amount, "local_amount": local_amount,
			"unload": unload, "unload_label": unload_label,
			"load": load, "load_label": load_label,
			"decrease": decrease, "amount_label": amount_label,
			"increase": increase, "amount_caption": amount_caption,
			"amount_index": AMOUNT_OPTIONS.size() - 1,
		}

	resized.connect(_layout)
	_layout()
	refresh()


func _make_label(text_value: String, font_size: int, colour: Color) -> Label:
	var label := Label.new()
	label.text = text_value
	label.mouse_filter = Control.MOUSE_FILTER_IGNORE
	label.add_theme_font_size_override("font_size", font_size)
	label.add_theme_color_override("font_color", colour)
	label.vertical_alignment = VERTICAL_ALIGNMENT_CENTER
	return label


func _request_transfer(resource_type: String, to_building: bool) -> void:
	var row: Dictionary = _rows.get(resource_type, {})
	if row.is_empty():
		return
	transfer_requested.emit(resource_type, to_building,
		AMOUNT_OPTIONS[int(row.amount_index)])


func _change_amount(resource_type: String, direction: int) -> void:
	var row: Dictionary = _rows.get(resource_type, {})
	if row.is_empty():
		return
	row.amount_index = clampi(int(row.amount_index) + direction, 0, AMOUNT_OPTIONS.size() - 1)
	_refresh_amount_controls(row)


func _refresh_amount_controls(row: Dictionary) -> void:
	var index: int = int(row.amount_index)
	var amount: int = AMOUNT_OPTIONS[index]
	row.amount_label.text = "ALL" if amount == ALL_AMOUNT else str(amount)
	row.decrease.enabled = index > 0
	row.increase.enabled = index < AMOUNT_OPTIONS.size() - 1
	row.decrease.queue_redraw()
	row.increase.queue_redraw()


func set_destination(id: int, heading: String) -> void:
	building_id = id
	extractor_index = -1
	if _destination_heading != null:
		_destination_heading.text = heading.to_upper()
	refresh()


func set_extractor_destination(index: int, heading: String) -> void:
	building_id = 0
	extractor_index = index
	if _destination_heading != null:
		_destination_heading.text = heading.to_upper()
	refresh()


func refresh() -> void:
	for resource_type in GameState.resource_types():
		var row: Dictionary = _rows.get(resource_type, {})
		if row.is_empty():
			continue
		var fleet_amount: int = GameState.fleet_resource(resource_type)
		var local_amount: int = GameState.extractor_resource(extractor_index, resource_type) \
			if extractor_index >= 0 else GameState.building_resource(building_id, resource_type)
		row.fleet_amount.text = str(fleet_amount)
		row.local_amount.text = str(local_amount)
		row.unload.enabled = fleet_amount > 0
		row.load.enabled = local_amount > 0
		row.unload.queue_redraw()
		row.load.queue_redraw()
		_refresh_amount_controls(row)


func _layout() -> void:
	if _destination_heading == null:
		return
	var side_width: float = size.x * 0.35
	var centre_width: float = size.x - side_width * 2.0
	var right_x: float = side_width + centre_width
	var fleet_heading: Label = get_child(0)
	fleet_heading.position = Vector2(0.0, 0.0)
	fleet_heading.size = Vector2(side_width, HEADER_HEIGHT)
	_destination_heading.position = Vector2(right_x, 0.0)
	_destination_heading.size = Vector2(side_width, HEADER_HEIGHT)

	var row_height: float = (size.y - HEADER_HEIGHT) / maxf(1.0, float(_rows.size()))
	var row_index: int = 0
	for resource_type in GameState.resource_types():
		var row: Dictionary = _rows[resource_type]
		var y: float = HEADER_HEIGHT + float(row_index) * row_height
		var glyph_size: float = minf(66.0, row_height * 0.23)
		row.glyph.position = Vector2(size.x * 0.5 - glyph_size * 0.5, y + 10.0)
		row.glyph.size = Vector2(glyph_size, glyph_size)
		row.name.position = Vector2(side_width, y + 10.0 + glyph_size)
		row.name.size = Vector2(centre_width, 44.0)

		row.fleet_amount.position = Vector2(0.0, y + 10.0)
		row.fleet_amount.size = Vector2(side_width, 70.0)
		row.local_amount.position = Vector2(right_x, y + 10.0)
		row.local_amount.size = Vector2(side_width, 70.0)

		var button_size: float = minf(132.0, row_height * 0.44)
		var button_y: float = y + 88.0
		row.unload.position = Vector2(side_width * 0.5 - button_size * 0.5, button_y)
		row.unload.size = Vector2(button_size, button_size)
		row.load.position = Vector2(right_x + side_width * 0.5 - button_size * 0.5, button_y)
		row.load.size = Vector2(button_size, button_size)
		var caption_y: float = button_y + button_size + 2.0
		row.unload_label.position = Vector2(0.0, caption_y)
		row.unload_label.size = Vector2(side_width, 42.0)
		row.load_label.position = Vector2(right_x, caption_y)
		row.load_label.size = Vector2(side_width, 42.0)

		var selector_size: float = minf(66.0, centre_width * 0.33)
		var selector_y: float = y + 142.0
		row.decrease.position = Vector2(side_width + 2.0, selector_y)
		row.decrease.size = Vector2(selector_size, selector_size)
		row.increase.position = Vector2(right_x - selector_size - 2.0, selector_y)
		row.increase.size = Vector2(selector_size, selector_size)
		row.amount_label.position = Vector2(side_width + selector_size + 2.0, selector_y)
		row.amount_label.size = Vector2(centre_width - selector_size * 2.0 - 4.0, selector_size)
		row.amount_caption.position = Vector2(side_width, selector_y + selector_size + 2.0)
		row.amount_caption.size = Vector2(centre_width, 34.0)
		row_index += 1
	queue_redraw()


func _draw() -> void:
	var row_height: float = (size.y - HEADER_HEIGHT) / maxf(1.0, float(_rows.size()))
	NeonDraw.draw_glowing_line(self, Vector2(0.0, HEADER_HEIGHT), Vector2(size.x, HEADER_HEIGHT),
		RULE_COLOR, 0.5, 0.7)
	for i in range(1, _rows.size()):
		var y: float = HEADER_HEIGHT + float(i) * row_height
		NeonDraw.draw_glowing_line(self, Vector2(0.0, y), Vector2(size.x, y),
			RULE_COLOR, 0.4, 0.6)