extends CanvasLayer

# Minimalistic Inventory UI with Stats Panel
# Toggle with Tab key, shows stats, equipment slots and inventory items

var is_open: bool = false
var local_player: Node = null

# Selection tracking
var selected_item: Item = null  # Selected inventory item
var selected_slot: String = ""  # Selected equipment slot name
var selected_type: String = ""  # "item" or "equipment"

# UI Nodes
var container: Control = null
var stats_panel: Control = null
var equipment_panel: Control = null
var inventory_grid: GridContainer = null
var scroll_container: ScrollContainer = null

# Stats labels
var label_base_stats: Label = null
var label_base_stats_value: Label = null
var label_derived_stats: Label = null
var label_derived_stats_value: Label = null

# Store button/item mappings for selection highlighting
var inventory_buttons: Dictionary = {}  # item -> button
var equipment_buttons: Dictionary = {}  # slot_name -> button

# Equipment slot buttons
var equipment_slots: Dictionary = {
	"mainhand": null,
	"offhand": null,
	"headgear": null,
	"armour": null,
	"boots": null,
	"accessory": null
}

func _ready():
	# Set layer to be above game but below chat
	layer = 150
	
	# Create UI structure
	_setup_ui()
	
	# Find local player
	call_deferred("_find_local_player")

func _find_local_player():
	# Find the local player
	var game_world = get_tree().get_first_node_in_group("game_world")
	if game_world:
		var player_manager = game_world.get_node_or_null("PlayerManager")
		if player_manager:
			var local_players = player_manager.get_local_players()
			if local_players.size() > 0:
				local_player = local_players[0]
				if local_player and local_player.character_stats:
					# Connect to character_changed signal
					if local_player.character_stats.character_changed.is_connected(_on_character_changed):
						local_player.character_stats.character_changed.disconnect(_on_character_changed)
					local_player.character_stats.character_changed.connect(_on_character_changed)
					# Initial update
					_update_ui()
					_update_stats()

func _setup_ui():
	# Main container (anchored to bottom-left, larger to fit stats + inventory)
	container = Control.new()
	container.name = "InventoryContainer"
	container.set_anchors_preset(Control.PRESET_BOTTOM_LEFT)
	container.offset_left = 10   # 10px padding from left
	container.offset_right = 10 + 620  # Width 620px (stats 200px + inventory 400px + gap 20px)
	container.offset_top = -350    # Height 340px (350 - 10)
	container.offset_bottom = -10  # 10px padding from bottom
	container.visible = false
	add_child(container)
	
	# Background panel
	var background = ColorRect.new()
	background.name = "Background"
	background.color = Color(0.1, 0.1, 0.1, 0.85)
	background.mouse_filter = Control.MOUSE_FILTER_IGNORE
	container.add_child(background)
	background.set_anchors_preset(Control.PRESET_FULL_RECT)
	
	# HBox for stats and inventory side by side
	var hbox = HBoxContainer.new()
	hbox.name = "HBox"
	container.add_child(hbox)
	hbox.set_anchors_preset(Control.PRESET_FULL_RECT)
	hbox.add_theme_constant_override("separation", 10)
	
	# Stats panel (left side)
	_create_stats_panel()
	hbox.add_child(stats_panel)
	
	# Inventory/Equipment panel (right side)
	var inv_panel = VBoxContainer.new()
	inv_panel.name = "InventoryPanel"
	inv_panel.custom_minimum_size = Vector2(400, 0)
	hbox.add_child(inv_panel)
	inv_panel.add_theme_constant_override("separation", 5)
	
	# Equipment label
	var eq_label = Label.new()
	eq_label.text = "Equipment"
	eq_label.add_theme_font_size_override("font_size", 14)
	var standard_font_resource = null
	if ResourceLoader.exists("res://assets/fonts/standard_font.png"):
		standard_font_resource = load("res://assets/fonts/standard_font.png")
		if standard_font_resource:
			eq_label.add_theme_font_override("font", standard_font_resource)
	inv_panel.add_child(eq_label)
	
	equipment_panel = GridContainer.new()
	equipment_panel.name = "EquipmentPanel"
	equipment_panel.columns = 3
	equipment_panel.add_theme_constant_override("h_separation", 5)
	equipment_panel.add_theme_constant_override("v_separation", 5)
	inv_panel.add_child(equipment_panel)
	
	# Create equipment slot buttons
	_create_equipment_slots()
	
	# Inventory label
	var inv_label = Label.new()
	inv_label.text = "Inventory"
	inv_label.add_theme_font_size_override("font_size", 14)
	if ResourceLoader.exists("res://assets/fonts/standard_font.png"):
		standard_font_resource = load("res://assets/fonts/standard_font.png")
		if standard_font_resource:
			inv_label.add_theme_font_override("font", standard_font_resource)
	inv_panel.add_child(inv_label)
	
	# Scroll container for inventory
	scroll_container = ScrollContainer.new()
	scroll_container.name = "InventoryScroll"
	scroll_container.custom_minimum_size = Vector2(380, 120)
	inv_panel.add_child(scroll_container)
	
	# Inventory grid
	inventory_grid = GridContainer.new()
	inventory_grid.name = "InventoryGrid"
	inventory_grid.columns = 6
	inventory_grid.add_theme_constant_override("h_separation", 3)
	inventory_grid.add_theme_constant_override("v_separation", 3)
	scroll_container.add_child(inventory_grid)

func _create_stats_panel():
	stats_panel = VBoxContainer.new()
	stats_panel.name = "StatsPanel"
	stats_panel.custom_minimum_size = Vector2(200, 0)
	
	# Stats label
	var stats_label = Label.new()
	stats_label.text = "Stats"
	stats_label.add_theme_font_size_override("font_size", 14)
	var standard_font_resource = null
	if ResourceLoader.exists("res://assets/fonts/standard_font.png"):
		standard_font_resource = load("res://assets/fonts/standard_font.png")
		if standard_font_resource:
			stats_label.add_theme_font_override("font", standard_font_resource)
	stats_panel.add_child(stats_label)
	
	# HBox for stats columns
	var stats_hbox = HBoxContainer.new()
	stats_hbox.name = "StatsHBox"
	stats_panel.add_child(stats_hbox)
	stats_hbox.add_theme_constant_override("separation", 5)
	
	# Base stats label
	label_base_stats = Label.new()
	label_base_stats.name = "LabelBaseStats"
	label_base_stats.text = "Level\n\nHP\nMP\n\nSTR\nDEX\nEND\nINT\nWIS\nLCK"
	label_base_stats.add_theme_font_size_override("font_size", 10)
	if ResourceLoader.exists("res://assets/fonts/standard_font.png"):
		var font_resource = load("res://assets/fonts/standard_font.png")
		if font_resource:
			label_base_stats.add_theme_font_override("font", font_resource)
	stats_hbox.add_child(label_base_stats)
	
	# Base stats values label
	label_base_stats_value = Label.new()
	label_base_stats_value.name = "LabelBaseStatsValue"
	label_base_stats_value.text = "1\n\n30/30\n20/20\n\n10\n10\n10\n10\n10\n10"
	label_base_stats_value.add_theme_font_size_override("font_size", 10)
	label_base_stats_value.horizontal_alignment = HORIZONTAL_ALIGNMENT_RIGHT
	if ResourceLoader.exists("res://assets/fonts/standard_font.png"):
		var font_resource = load("res://assets/fonts/standard_font.png")
		if font_resource:
			label_base_stats_value.add_theme_font_override("font", font_resource)
	stats_hbox.add_child(label_base_stats_value)
	
	# Derived stats label
	label_derived_stats = Label.new()
	label_derived_stats.name = "LabelDerivedStats"
	label_derived_stats.text = "XP\nCoin\n\n\n\nDMG\nDEF\nMovSpd\nAtkSpd\nSight\nSpellAmp\nCrit%"
	label_derived_stats.add_theme_font_size_override("font_size", 10)
	if ResourceLoader.exists("res://assets/fonts/standard_font.png"):
		var font_resource = load("res://assets/fonts/standard_font.png")
		if font_resource:
			label_derived_stats.add_theme_font_override("font", font_resource)
	stats_hbox.add_child(label_derived_stats)
	
	# Derived stats values label
	label_derived_stats_value = Label.new()
	label_derived_stats_value.name = "LabelDerivedStatsValue"
	label_derived_stats_value.text = "0/100\n0\n\n\n\n2.0\n2.0\n2.1\n1.4\n7.0\n5.0\n12.0%"
	label_derived_stats_value.add_theme_font_size_override("font_size", 10)
	label_derived_stats_value.horizontal_alignment = HORIZONTAL_ALIGNMENT_RIGHT
	if ResourceLoader.exists("res://assets/fonts/standard_font.png"):
		var font_resource = load("res://assets/fonts/standard_font.png")
		if font_resource:
			label_derived_stats_value.add_theme_font_override("font", font_resource)
	stats_hbox.add_child(label_derived_stats_value)

func _update_stats():
	if not local_player or not local_player.character_stats:
		return
	
	var char_stats = local_player.character_stats
	
	# Update base stats
	label_base_stats_value.text = str(char_stats.level) + "\n\n" + \
		str(int(char_stats.hp)) + "/" + str(int(char_stats.maxhp)) + "\n" + \
		str(int(char_stats.mp)) + "/" + str(int(char_stats.maxmp)) + "\n\n" + \
		str(char_stats.baseStats.str) + "\n" + \
		str(char_stats.baseStats.dex) + "\n" + \
		str(char_stats.baseStats.end) + "\n" + \
		str(char_stats.baseStats.int) + "\n" + \
		str(char_stats.baseStats.wis) + "\n" + \
		str(char_stats.baseStats.lck)
	
	# Update derived stats
	label_derived_stats_value.text = str(int(char_stats.xp)) + "/" + str(int(char_stats.xp_to_next_level)) + "\n" + \
		str(char_stats.coin) + "\n\n\n\n" + \
		str(char_stats.damage) + "\n" + \
		str(char_stats.defense) + "\n" + \
		str(char_stats.move_speed) + "\n" + \
		str(char_stats.attack_speed) + "\n" + \
		str(char_stats.sight) + "\n" + \
		str(char_stats.spell_amp) + "\n" + \
		str(char_stats.crit_chance) + "%"

func _create_equipment_slots():
	# Equipment slot order: mainhand, offhand, headgear, armour, boots, accessory
	var slot_names = ["mainhand", "offhand", "headgear", "armour", "boots", "accessory"]
	var slot_labels = ["Weapon", "Shield", "Head", "Armour", "Boots", "Accessory"]
	
	for i in range(slot_names.size()):
		var slot_name = slot_names[i]
		var slot_label = slot_labels[i]
		
		# Container for slot
		var slot_container = VBoxContainer.new()
		slot_container.name = slot_name + "_slot"
		equipment_panel.add_child(slot_container)
		
		# Label
		var label = Label.new()
		label.text = slot_label
		label.add_theme_font_size_override("font_size", 10)
		label.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
		if ResourceLoader.exists("res://assets/fonts/standard_font.png"):
			var font_resource = load("res://assets/fonts/standard_font.png")
			if font_resource:
				label.add_theme_font_override("font", font_resource)
		slot_container.add_child(label)
		
		# Button
		var button = Button.new()
		button.name = slot_name + "_btn"
		button.custom_minimum_size = Vector2(60, 60)
		button.flat = true
		button.connect("pressed", _on_equipment_slot_pressed.bind(slot_name))
		slot_container.add_child(button)
		
		equipment_slots[slot_name] = button
		equipment_buttons[slot_name] = button

func _on_equipment_slot_pressed(slot_name: String):
	if not local_player or not local_player.character_stats:
		return
	
	# Select this slot
	selected_slot = slot_name
	selected_item = local_player.character_stats.equipment[slot_name]
	selected_type = "equipment" if selected_item else ""
	_update_selection_highlight()

func _update_selection_highlight():
	# Reset all button styles
	for button in equipment_buttons.values():
		if button:
			var highlight = button.get_node_or_null("Highlight")
			if highlight:
				highlight.queue_free()
	
	for button in inventory_buttons.values():
		if button:
			var highlight = button.get_node_or_null("Highlight")
			if highlight:
				highlight.queue_free()
	
	# Highlight selected equipment slot
	if selected_type == "equipment" and selected_slot != "":
		var button = equipment_buttons.get(selected_slot)
		if button:
			var highlight = ColorRect.new()
			highlight.name = "Highlight"
			highlight.color = Color(1.0, 1.0, 0.0, 0.6)
			highlight.mouse_filter = Control.MOUSE_FILTER_IGNORE
			highlight.z_index = 10
			button.add_child(highlight)
			highlight.set_anchors_preset(Control.PRESET_FULL_RECT)
	
	# Highlight selected inventory item
	if selected_type == "item" and selected_item:
		var button = inventory_buttons.get(selected_item)
		if button:
			var highlight = ColorRect.new()
			highlight.name = "Highlight"
			highlight.color = Color(1.0, 1.0, 0.0, 0.6)
			highlight.mouse_filter = Control.MOUSE_FILTER_IGNORE
			highlight.z_index = 10
			button.add_child(highlight)
			highlight.set_anchors_preset(Control.PRESET_FULL_RECT)

func _update_ui():
	if not local_player or not local_player.character_stats:
		return
	
	var char_stats = local_player.character_stats
	
	# Clear button mappings
	inventory_buttons.clear()
	
	# Update equipment slots
	for slot_name in equipment_slots.keys():
		var button = equipment_slots[slot_name]
		if not button:
			continue
		
		# Clear existing children (sprite, highlight)
		for child in button.get_children():
			child.queue_free()
		
		var equipped_item = char_stats.equipment[slot_name]
		if equipped_item:
			var sprite = Sprite2D.new()
			var texture_path = ""
			var use_equipment_path = false
			
			if slot_name == "mainhand" or slot_name == "offhand":
				texture_path = equipped_item.spritePath
				use_equipment_path = false
			else:
				texture_path = equipped_item.equipmentPath if equipped_item.equipmentPath != "" else equipped_item.spritePath
				use_equipment_path = (equipped_item.equipmentPath != "")
			
			var texture = load(texture_path)
			if texture:
				sprite.texture = texture
				if use_equipment_path:
					sprite.hframes = 35
					sprite.vframes = 8
				else:
					sprite.hframes = equipped_item.spriteFrames.x if equipped_item.spriteFrames.x > 0 else 20
					sprite.vframes = equipped_item.spriteFrames.y if equipped_item.spriteFrames.y > 0 else 14
					sprite.frame = equipped_item.spriteFrame
				sprite.scale = Vector2(1.2, 1.2)
				button.add_child(sprite)
	
	# Update inventory grid
	for child in inventory_grid.get_children():
		child.queue_free()
	
	for item in char_stats.inventory:
		var button = Button.new()
		button.custom_minimum_size = Vector2(60, 60)
		button.flat = true
		button.connect("pressed", _on_inventory_item_pressed.bind(item))
		
		if item.spritePath != "":
			var sprite = Sprite2D.new()
			var texture = load(item.spritePath)
			if texture:
				sprite.texture = texture
				sprite.hframes = item.spriteFrames.x if item.spriteFrames.x > 0 else 20
				sprite.vframes = item.spriteFrames.y if item.spriteFrames.y > 0 else 14
				sprite.frame = item.spriteFrame
				sprite.scale = Vector2(1.2, 1.2)
				button.add_child(sprite)
		
		inventory_grid.add_child(button)
		inventory_buttons[item] = button
	
	# Update selection highlight
	_update_selection_highlight()
	
	# Update stats
	_update_stats()

func _on_inventory_item_pressed(item: Item):
	if not local_player or not local_player.character_stats:
		return
	
	selected_item = item
	selected_slot = ""
	selected_type = "item"
	_update_selection_highlight()

func _on_character_changed(_char: CharacterStats):
	_update_ui()
	_update_stats()

func _input(event):
	# Toggle with Tab key
	if event is InputEventKey and event.keycode == KEY_TAB and event.pressed and not event.echo:
		if is_open:
			_close_inventory()
		else:
			_open_inventory()
		get_viewport().set_input_as_handled()
		return
	
	if not is_open:
		return
	
	# F key: Unequip/equip items
	if event is InputEventKey and event.keycode == KEY_F and event.pressed and not event.echo:
		_handle_f_key()
		get_viewport().set_input_as_handled()
		return
	
	# E key: Drop selected item
	if event is InputEventKey and event.keycode == KEY_E and event.pressed and not event.echo:
		_handle_e_key()
		get_viewport().set_input_as_handled()
		return

func _handle_f_key():
	if not local_player or not local_player.character_stats:
		return
	
	var char_stats = local_player.character_stats
	
	if selected_type == "equipment" and selected_slot != "":
		var equipped_item = char_stats.equipment[selected_slot]
		if equipped_item:
			char_stats.unequip_item(equipped_item)
			selected_item = null
			selected_slot = ""
			selected_type = ""
			return
	
	if selected_type == "item" and selected_item:
		if selected_item.item_type == Item.ItemType.Equippable and selected_item.equipment_type != Item.EquipmentType.NONE:
			char_stats.equip_item(selected_item)
			selected_item = null
			selected_slot = ""
			selected_type = ""
		elif selected_item.item_type == Item.ItemType.Restoration:
			_use_consumable_item(selected_item)
			selected_item = null
			selected_slot = ""
			selected_type = ""

func _use_consumable_item(item: Item):
	if not local_player or not local_player.character_stats:
		return
	
	var char_stats = local_player.character_stats
	
	if item.modifiers.has("hp"):
		var hp_heal = item.modifiers["hp"]
		if local_player.has_method("heal"):
			local_player.heal(hp_heal)
	if item.modifiers.has("mp"):
		var mana_amount = item.modifiers["mp"]
		char_stats.restore_mana(mana_amount)
	
	var index = char_stats.inventory.find(item)
	if index >= 0:
		char_stats.inventory.remove_at(index)
		char_stats.character_changed.emit(char_stats)
	
	print(local_player.name, " used item: ", item.item_name)

func _handle_e_key():
	if not local_player or not local_player.character_stats:
		return
	
	if selected_type != "item" or not selected_item:
		return
	
	var char_stats = local_player.character_stats
	
	if not selected_item in char_stats.inventory:
		return
	
	var index = char_stats.inventory.find(selected_item)
	if index >= 0:
		char_stats.inventory.remove_at(index)
	
	var drop_position = local_player.global_position + Vector2(randf_range(-20, 20), randf_range(-20, 20))
	var game_world = get_tree().get_first_node_in_group("game_world")
	var entities_node = null
	if game_world:
		entities_node = game_world.get_node_or_null("Entities")
	
	if entities_node:
		var loot = ItemLootHelper.spawn_item_loot(selected_item, drop_position, entities_node, game_world)
		if loot:
			if local_player.has_method("get_multiplayer_authority"):
				var player_peer_id = local_player.get_multiplayer_authority()
				loot.set_meta("dropped_by_peer_id", player_peer_id)
				loot.set_meta("drop_time", Time.get_ticks_msec())
	
	selected_item = null
	selected_slot = ""
	selected_type = ""
	
	char_stats.character_changed.emit(char_stats)
	
	print(local_player.name, " dropped item")

func _open_inventory():
	if is_open:
		return
	
	is_open = true
	if container:
		container.visible = true
	
	_lock_player_controls(true)
	_update_ui()
	
	if not local_player:
		_find_local_player()

func _close_inventory():
	if not is_open:
		return
	
	is_open = false
	if container:
		container.visible = false
	
	selected_item = null
	selected_slot = ""
	selected_type = ""
	
	_lock_player_controls(false)

func _lock_player_controls(lock: bool):
	var game_world = get_tree().get_first_node_in_group("game_world")
	if game_world:
		var player_manager = game_world.get_node_or_null("PlayerManager")
		if player_manager:
			var local_players = player_manager.get_local_players()
			for player in local_players:
				player.controls_disabled = lock