class_name GameSetupMenu
extends CanvasLayer

## GameSetupMenu - Setup screen for configuring game before starting
## Allows selection of game type and decks for each player

signal back_pressed
signal start_game_requested(p1_deck: Array, p2_deck: Array)

const WINDOW_SIZE := Vector2(800, 600)

# UI Components
var background: PanelContainer
var main_vbox: VBoxContainer
var title_label: Label
var game_type_container: HBoxContainer
var game_type_dropdown: OptionButton
var players_container: HBoxContainer
var player1_panel: Control
var player2_panel: Control
var p1_deck_dropdown: OptionButton
var p2_deck_dropdown: OptionButton
var p1_preview: Control
var p2_preview: Control
var buttons_container: HBoxContainer
var start_button: Button
var back_button: Button

# Deck data
var saved_decks: Array[String] = []
var starter_decks: Array = []  # Array of StarterDeckData
var p1_selected_deck: Array = []  # Card IDs
var p2_selected_deck: Array = []  # Card IDs


func _ready() -> void:
	# Set high layer to be on top of everything
	layer = 100
	_load_deck_options()
	_create_ui()
	_select_random_decks()


func _load_deck_options() -> void:
	# Load saved decks
	saved_decks = DeckManager.list_decks()

	# Load starter decks
	starter_decks = CardDatabase.get_starter_decks()


func _create_ui() -> void:
	# Background panel - use the window size constant
	background = PanelContainer.new()
	add_child(background)
	background.position = Vector2.ZERO
	background.size = WINDOW_SIZE
	background.add_theme_stylebox_override("panel", _create_panel_style())

	# Main vertical layout with padding
	var margin = MarginContainer.new()
	background.add_child(margin)
	margin.set_anchors_and_offsets_preset(Control.PRESET_FULL_RECT)
	margin.add_theme_constant_override("margin_left", 25)
	margin.add_theme_constant_override("margin_right", 25)
	margin.add_theme_constant_override("margin_top", 15)
	margin.add_theme_constant_override("margin_bottom", 15)

	main_vbox = VBoxContainer.new()
	margin.add_child(main_vbox)
	main_vbox.add_theme_constant_override("separation", 8)

	# Title
	_create_title()

	# Game type selector
	_create_game_type_selector()

	# Player panels
	_create_player_panels()

	# Spacer
	var spacer = Control.new()
	spacer.size_flags_vertical = Control.SIZE_EXPAND_FILL
	main_vbox.add_child(spacer)

	# Buttons
	_create_buttons()


func _create_title() -> void:
	title_label = Label.new()
	title_label.text = "GAME SETUP"
	title_label.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
	title_label.add_theme_font_size_override("font_size", 32)
	title_label.add_theme_color_override("font_color", Color(1.0, 0.95, 0.8))
	main_vbox.add_child(title_label)

	# Separator
	var separator = HSeparator.new()
	separator.add_theme_stylebox_override("separator", _create_separator_style())
	main_vbox.add_child(separator)


func _create_game_type_selector() -> void:
	game_type_container = HBoxContainer.new()
	game_type_container.add_theme_constant_override("separation", 15)
	main_vbox.add_child(game_type_container)

	var label = Label.new()
	label.text = "Game Type:"
	label.add_theme_font_size_override("font_size", 18)
	label.add_theme_color_override("font_color", Color(0.9, 0.85, 0.7))
	game_type_container.add_child(label)

	game_type_dropdown = OptionButton.new()
	game_type_dropdown.custom_minimum_size = Vector2(250, 36)
	game_type_dropdown.add_item("2-Player Local (Share Screen)")
	game_type_dropdown.add_item("vs AI (Coming Soon)")
	game_type_dropdown.set_item_disabled(1, true)
	game_type_dropdown.add_theme_font_size_override("font_size", 14)
	_style_dropdown(game_type_dropdown)
	game_type_container.add_child(game_type_dropdown)


func _create_player_panels() -> void:
	players_container = HBoxContainer.new()
	players_container.add_theme_constant_override("separation", 20)
	players_container.alignment = BoxContainer.ALIGNMENT_CENTER
	main_vbox.add_child(players_container)

	player1_panel = _create_player_panel("PLAYER 1", 1)
	players_container.add_child(player1_panel)

	player2_panel = _create_player_panel("PLAYER 2", 2)
	players_container.add_child(player2_panel)


func _create_player_panel(title: String, player_num: int) -> Control:
	var panel = PanelContainer.new()
	panel.custom_minimum_size = Vector2(320, 280)
	panel.add_theme_stylebox_override("panel", _create_player_panel_style())

	var vbox = VBoxContainer.new()
	vbox.add_theme_constant_override("separation", 8)
	panel.add_child(vbox)

	var margin = MarginContainer.new()
	margin.add_theme_constant_override("margin_left", 12)
	margin.add_theme_constant_override("margin_right", 12)
	margin.add_theme_constant_override("margin_top", 8)
	margin.add_theme_constant_override("margin_bottom", 8)
	vbox.add_child(margin)

	var inner_vbox = VBoxContainer.new()
	inner_vbox.add_theme_constant_override("separation", 6)
	margin.add_child(inner_vbox)

	# Player title
	var title_label = Label.new()
	title_label.text = title
	title_label.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
	title_label.add_theme_font_size_override("font_size", 18)
	title_label.add_theme_color_override("font_color", Color(1.0, 0.95, 0.8))
	inner_vbox.add_child(title_label)

	# Deck dropdown
	var dropdown = OptionButton.new()
	dropdown.custom_minimum_size = Vector2(300, 32)
	dropdown.add_theme_font_size_override("font_size", 12)
	_style_dropdown(dropdown)
	_populate_deck_dropdown(dropdown)
	dropdown.item_selected.connect(_on_deck_selected.bind(player_num))
	inner_vbox.add_child(dropdown)

	if player_num == 1:
		p1_deck_dropdown = dropdown
	else:
		p2_deck_dropdown = dropdown

	# Deck preview panel (with box art)
	var preview = _create_deck_preview(player_num)
	inner_vbox.add_child(preview)

	if player_num == 1:
		p1_preview = preview
	else:
		p2_preview = preview

	return panel


func _create_deck_preview(player_num: int) -> Control:
	var panel = PanelContainer.new()
	panel.custom_minimum_size = Vector2(280, 170)

	var style = StyleBoxFlat.new()
	style.bg_color = Color(0.06, 0.06, 0.1, 0.8)
	style.border_color = Color(0.3, 0.3, 0.35)
	style.set_border_width_all(1)
	style.set_corner_radius_all(4)
	style.content_margin_left = 8
	style.content_margin_right = 8
	style.content_margin_top = 6
	style.content_margin_bottom = 6
	panel.add_theme_stylebox_override("panel", style)

	var vbox = VBoxContainer.new()
	vbox.name = "VBoxContainer"
	vbox.add_theme_constant_override("separation", 4)
	panel.add_child(vbox)

	# Box art container (centered)
	var art_container = CenterContainer.new()
	art_container.name = "ArtContainer"
	art_container.custom_minimum_size = Vector2(260, 90)
	vbox.add_child(art_container)

	# Box art image
	var box_art = TextureRect.new()
	box_art.name = "BoxArt"
	box_art.custom_minimum_size = Vector2(90, 85)
	box_art.expand_mode = TextureRect.EXPAND_FIT_HEIGHT_PROPORTIONAL
	box_art.stretch_mode = TextureRect.STRETCH_KEEP_ASPECT_CENTERED
	art_container.add_child(box_art)

	# Placeholder when no art available
	var placeholder = ColorRect.new()
	placeholder.name = "Placeholder"
	placeholder.custom_minimum_size = Vector2(60, 85)
	placeholder.color = Color(0.15, 0.15, 0.2, 0.5)
	placeholder.visible = true
	art_container.add_child(placeholder)

	# Placeholder icon/text
	var placeholder_label = Label.new()
	placeholder_label.text = "?"
	placeholder_label.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
	placeholder_label.vertical_alignment = VERTICAL_ALIGNMENT_CENTER
	placeholder_label.add_theme_font_size_override("font_size", 48)
	placeholder_label.add_theme_color_override("font_color", Color(0.3, 0.3, 0.35))
	placeholder.add_child(placeholder_label)
	placeholder_label.set_anchors_preset(Control.PRESET_FULL_RECT)

	# Deck name
	var name_label = Label.new()
	name_label.name = "DeckName"
	name_label.text = "No deck selected"
	name_label.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
	name_label.add_theme_font_size_override("font_size", 14)
	name_label.add_theme_color_override("font_color", Color(0.9, 0.85, 0.7))
	vbox.add_child(name_label)

	# Elements row (centered)
	var elements_center = CenterContainer.new()
	elements_center.name = "ElementsCenter"
	vbox.add_child(elements_center)

	var elements_hbox = HBoxContainer.new()
	elements_hbox.name = "ElementsRow"
	elements_hbox.add_theme_constant_override("separation", 6)
	elements_center.add_child(elements_hbox)

	# Info row (card count + description)
	var info_hbox = HBoxContainer.new()
	info_hbox.name = "InfoRow"
	info_hbox.alignment = BoxContainer.ALIGNMENT_CENTER
	info_hbox.add_theme_constant_override("separation", 10)
	vbox.add_child(info_hbox)

	# Card count
	var count_label = Label.new()
	count_label.name = "CardCount"
	count_label.text = "0 cards"
	count_label.add_theme_font_size_override("font_size", 11)
	count_label.add_theme_color_override("font_color", Color(0.6, 0.6, 0.6))
	info_hbox.add_child(count_label)

	# Separator
	var sep = Label.new()
	sep.text = "•"
	sep.add_theme_font_size_override("font_size", 11)
	sep.add_theme_color_override("font_color", Color(0.4, 0.4, 0.4))
	info_hbox.add_child(sep)

	# Description
	var desc_label = Label.new()
	desc_label.name = "Description"
	desc_label.text = ""
	desc_label.add_theme_font_size_override("font_size", 11)
	desc_label.add_theme_color_override("font_color", Color(0.5, 0.5, 0.55))
	info_hbox.add_child(desc_label)

	return panel


func _populate_deck_dropdown(dropdown: OptionButton) -> void:
	dropdown.clear()

	# Add "My Decks" section if there are saved decks
	if not saved_decks.is_empty():
		dropdown.add_separator("-- My Decks --")
		for deck_name in saved_decks:
			dropdown.add_item(deck_name)
			dropdown.set_item_metadata(dropdown.get_item_count() - 1, {"type": "saved", "name": deck_name})

	# Add "Starter Decks" section
	dropdown.add_separator("-- Starter Decks --")
	for starter_deck in starter_decks:
		var display_name = "%s (%s)" % [starter_deck.name, starter_deck.opus]
		dropdown.add_item(display_name)
		dropdown.set_item_metadata(dropdown.get_item_count() - 1, {"type": "starter", "id": starter_deck.id})


func _select_random_decks() -> void:
	# Select random starter decks for both players
	if starter_decks.size() >= 2:
		var indices = range(starter_decks.size())
		indices.shuffle()

		var p1_index = _find_dropdown_index_for_starter(p1_deck_dropdown, starter_decks[indices[0]].id)
		var p2_index = _find_dropdown_index_for_starter(p2_deck_dropdown, starter_decks[indices[1]].id)

		if p1_index >= 0:
			p1_deck_dropdown.select(p1_index)
			_on_deck_selected(p1_index, 1)

		if p2_index >= 0:
			p2_deck_dropdown.select(p2_index)
			_on_deck_selected(p2_index, 2)
	elif starter_decks.size() == 1:
		var index = _find_dropdown_index_for_starter(p1_deck_dropdown, starter_decks[0].id)
		if index >= 0:
			p1_deck_dropdown.select(index)
			_on_deck_selected(index, 1)
			p2_deck_dropdown.select(index)
			_on_deck_selected(index, 2)


func _find_dropdown_index_for_starter(dropdown: OptionButton, starter_id: String) -> int:
	for i in range(dropdown.get_item_count()):
		var meta = dropdown.get_item_metadata(i)
		if meta is Dictionary and meta.get("type") == "starter" and meta.get("id") == starter_id:
			return i
	return -1


func _on_deck_selected(index: int, player_num: int) -> void:
	var dropdown = p1_deck_dropdown if player_num == 1 else p2_deck_dropdown
	var preview = p1_preview if player_num == 1 else p2_preview

	var meta = dropdown.get_item_metadata(index)
	if not meta is Dictionary:
		return

	var deck_cards: Array = []
	var deck_name: String = ""
	var deck_elements: Array = []
	var deck_description: String = ""
	var deck_texture: Texture2D = null

	if meta.get("type") == "saved":
		var deck = DeckManager.load_deck(meta.get("name"))
		if deck:
			deck_cards = deck.to_card_array()
			deck_name = deck.name
			deck_elements = _get_elements_from_deck(deck_cards)
			deck_description = "Custom deck"
			# No box art for custom decks
	elif meta.get("type") == "starter":
		var starter = CardDatabase.get_starter_deck(meta.get("id"))
		if starter:
			deck_cards = starter.cards.duplicate()
			deck_name = starter.name
			deck_elements = starter.elements
			deck_description = starter.description
			deck_texture = starter.get_texture()

	# Store selected deck
	if player_num == 1:
		p1_selected_deck = deck_cards
	else:
		p2_selected_deck = deck_cards

	# Update preview
	_update_preview(preview, deck_name, deck_elements, deck_cards.size(), deck_description, deck_texture)

	# Update start button state
	_update_start_button()


func _get_elements_from_deck(card_ids: Array) -> Array:
	var elements: Dictionary = {}
	for card_id in card_ids:
		var card = CardDatabase.get_card(card_id)
		if card:
			for element in card.elements:
				var elem_name = Enums.element_to_string(element)
				elements[elem_name] = elements.get(elem_name, 0) + 1

	# Sort by count and return top elements
	var sorted_elements: Array = []
	for elem_name in elements.keys():
		sorted_elements.append({"name": elem_name, "count": elements[elem_name]})
	sorted_elements.sort_custom(func(a, b): return a.count > b.count)

	var result: Array = []
	for i in range(mini(2, sorted_elements.size())):
		result.append(sorted_elements[i].name)
	return result


func _update_preview(preview: Control, deck_name: String, elements: Array, card_count: int, description: String, texture: Texture2D = null) -> void:
	var box_art = preview.get_node_or_null("VBoxContainer/ArtContainer/BoxArt") as TextureRect
	var placeholder = preview.get_node_or_null("VBoxContainer/ArtContainer/Placeholder") as ColorRect
	var name_label = preview.get_node_or_null("VBoxContainer/DeckName") as Label
	var elements_row = preview.get_node_or_null("VBoxContainer/ElementsCenter/ElementsRow") as HBoxContainer
	var count_label = preview.get_node_or_null("VBoxContainer/InfoRow/CardCount") as Label
	var desc_label = preview.get_node_or_null("VBoxContainer/InfoRow/Description") as Label

	# Update box art
	if box_art and placeholder:
		if texture:
			box_art.texture = texture
			box_art.visible = true
			placeholder.visible = false
		else:
			box_art.texture = null
			box_art.visible = false
			placeholder.visible = true

	if name_label:
		name_label.text = deck_name if not deck_name.is_empty() else "No deck selected"

	if elements_row:
		# Clear existing elements
		for child in elements_row.get_children():
			child.queue_free()

		# Add element indicators
		for elem_name in elements:
			var elem_container = HBoxContainer.new()
			elem_container.add_theme_constant_override("separation", 4)

			var color_rect = ColorRect.new()
			color_rect.custom_minimum_size = Vector2(12, 12)
			var element = Enums.element_from_string(elem_name)
			color_rect.color = Enums.element_to_color(element)
			elem_container.add_child(color_rect)

			var elem_label = Label.new()
			elem_label.text = elem_name
			elem_label.add_theme_font_size_override("font_size", 11)
			elem_label.add_theme_color_override("font_color", Color(0.8, 0.8, 0.8))
			elem_container.add_child(elem_label)

			elements_row.add_child(elem_container)

	if count_label:
		count_label.text = "%d cards" % card_count

	if desc_label:
		desc_label.text = description


func _update_start_button() -> void:
	# Require at least 1 card in each deck to start (relaxed from 50 for testing with incomplete card databases)
	var can_start = p1_selected_deck.size() >= 1 and p2_selected_deck.size() >= 1
	start_button.disabled = not can_start

	if can_start:
		start_button.add_theme_color_override("font_color", Color(0.9, 0.85, 0.7))
	else:
		start_button.add_theme_color_override("font_color", Color(0.5, 0.5, 0.5))


func _create_buttons() -> void:
	buttons_container = HBoxContainer.new()
	buttons_container.add_theme_constant_override("separation", 20)
	buttons_container.alignment = BoxContainer.ALIGNMENT_CENTER
	main_vbox.add_child(buttons_container)

	back_button = _create_styled_button("Back", Color(0.3, 0.25, 0.25))
	back_button.pressed.connect(_on_back_pressed)
	buttons_container.add_child(back_button)

	start_button = _create_styled_button("Start Game", Color(0.2, 0.35, 0.25))
	start_button.custom_minimum_size.x = 180
	start_button.pressed.connect(_on_start_pressed)
	start_button.disabled = true
	buttons_container.add_child(start_button)


func _create_styled_button(text: String, base_color: Color) -> Button:
	var button = Button.new()
	button.text = text
	button.custom_minimum_size = Vector2(140, 44)
	button.add_theme_font_size_override("font_size", 16)

	var style_normal = StyleBoxFlat.new()
	style_normal.bg_color = base_color
	style_normal.border_color = Color(0.5, 0.4, 0.2)
	style_normal.set_border_width_all(2)
	style_normal.set_corner_radius_all(6)
	button.add_theme_stylebox_override("normal", style_normal)

	var style_hover = StyleBoxFlat.new()
	style_hover.bg_color = base_color.lightened(0.15)
	style_hover.border_color = Color(0.7, 0.55, 0.3)
	style_hover.set_border_width_all(2)
	style_hover.set_corner_radius_all(6)
	button.add_theme_stylebox_override("hover", style_hover)

	var style_pressed = StyleBoxFlat.new()
	style_pressed.bg_color = base_color.darkened(0.1)
	style_pressed.border_color = Color(0.5, 0.4, 0.2)
	style_pressed.set_border_width_all(2)
	style_pressed.set_corner_radius_all(6)
	button.add_theme_stylebox_override("pressed", style_pressed)

	var style_disabled = StyleBoxFlat.new()
	style_disabled.bg_color = Color(0.15, 0.15, 0.18)
	style_disabled.border_color = Color(0.3, 0.3, 0.3)
	style_disabled.set_border_width_all(2)
	style_disabled.set_corner_radius_all(6)
	button.add_theme_stylebox_override("disabled", style_disabled)

	button.add_theme_color_override("font_color", Color(0.9, 0.85, 0.7))
	button.add_theme_color_override("font_hover_color", Color(1.0, 0.95, 0.8))
	button.add_theme_color_override("font_pressed_color", Color(0.7, 0.65, 0.55))
	button.add_theme_color_override("font_disabled_color", Color(0.4, 0.4, 0.4))

	return button


func _style_dropdown(dropdown: OptionButton) -> void:
	var style = StyleBoxFlat.new()
	style.bg_color = Color(0.12, 0.12, 0.16)
	style.border_color = Color(0.4, 0.35, 0.25)
	style.set_border_width_all(1)
	style.set_corner_radius_all(4)
	style.content_margin_left = 10
	style.content_margin_right = 10
	style.content_margin_top = 6
	style.content_margin_bottom = 6

	dropdown.add_theme_stylebox_override("normal", style)

	var hover_style = style.duplicate()
	hover_style.border_color = Color(0.6, 0.5, 0.3)
	dropdown.add_theme_stylebox_override("hover", hover_style)

	dropdown.add_theme_color_override("font_color", Color(0.9, 0.85, 0.7))
	dropdown.add_theme_color_override("font_hover_color", Color(1.0, 0.95, 0.8))


func _create_panel_style() -> StyleBoxFlat:
	var style = StyleBoxFlat.new()
	style.bg_color = Color(0.08, 0.08, 0.12, 1.0)
	# No border on the outer panel to avoid gaps at window edges
	style.set_border_width_all(0)
	style.set_corner_radius_all(0)
	return style


func _create_player_panel_style() -> StyleBoxFlat:
	var style = StyleBoxFlat.new()
	style.bg_color = Color(0.1, 0.1, 0.14, 0.9)
	style.border_color = Color(0.4, 0.35, 0.25)
	style.set_border_width_all(2)
	style.set_corner_radius_all(6)
	return style


func _create_separator_style() -> StyleBoxFlat:
	var style = StyleBoxFlat.new()
	style.bg_color = Color(0.5, 0.4, 0.2, 0.5)
	style.content_margin_top = 1
	return style


func _on_back_pressed() -> void:
	back_pressed.emit()


func _on_start_pressed() -> void:
	if p1_selected_deck.size() >= 1 and p2_selected_deck.size() >= 1:
		start_game_requested.emit(p1_selected_deck, p2_selected_deck)