extends Control
## World list screen — browses public worlds via GET /api/worlds.
##
## Displays a scrollable list of world cards (name + description).
## Handles loading, empty list, errors, and refresh.

const WORLD_CARD_SCENE := preload("res://scenes/world_card.tscn")

# UI references
@onready var scroll_container: ScrollContainer = $VBoxContainer/ScrollContainer
@onready var world_list: VBoxContainer = $VBoxContainer/ScrollContainer/WorldList
@onready var loading_label: Label = $VBoxContainer/LoadingLabel
@onready var error_label: Label = $VBoxContainer/ErrorLabel
@onready var refresh_button: Button = $VBoxContainer/RefreshButton
@onready var back_button: Button = $VBoxContainer/BackButton
@onready var empty_label: Label = $VBoxContainer/EmptyLabel


func _ready() -> void:
	refresh_button.disabled = false
	back_button.disabled = false
	loading_label.visible = false
	error_label.visible = false
	empty_label.visible = false
	world_list.visible = false
	_refresh_worlds()


func _on_refresh_button_pressed() -> void:
	_refresh_worlds()


func _on_back_button_pressed() -> void:
	get_tree().change_scene_to_file("res://scenes/main_menu.tscn")


## Fetch the world list from the backend and update the UI.
func _refresh_worlds() -> void:
	# Reset UI state
	loading_label.visible = true
	error_label.visible = false
	empty_label.visible = false
	world_list.visible = false
	refresh_button.disabled = true

	# Clear previous world cards
	for child in world_list.get_children():
		child.queue_free()

	var result := await ApiClient.get_worlds()

	loading_label.visible = false
	refresh_button.disabled = false

	if not result.ok:
		# Show error message (401, network failure, etc.)
		error_label.text = "Error: %s" % result.detail
		error_label.visible = true
		empty_label.visible = false
		world_list.visible = false
		return

	var data = result.data
	if not data is Array:
		error_label.text = "Unexpected response format."
		error_label.visible = true
		empty_label.visible = false
		world_list.visible = false
		return

	if data.is_empty():
		empty_label.text = "No worlds yet. Check back later!"
		empty_label.visible = true
		error_label.visible = false
		world_list.visible = false
		return

	# Render world cards
	world_list.visible = true
	empty_label.visible = false
	error_label.visible = false

	for world_dict in data:
		if not world_dict is Dictionary:
			continue
		var card := _create_world_card(world_dict)
		world_list.add_child(card)


## Create a visual card for a single world entry.
func _create_world_card(world_dict: Dictionary) -> Control:
	var card := VBoxContainer.new()
	card.size_flags_horizontal = Control.SIZE_FILL
	card.custom_minimum_size = Vector2(0, 80)
	card.theme_override_constants/separation = 4

	var name_label := Label.new()
	name_label.text = world_dict.get("name", "Unnamed World")
	name_label.autowrap_mode = TextServer.AUTOWRAP_WORD
	name_label.size_flags_horizontal = Control.SIZE_FILL
	name_label.size_flags_vertical = Control.SIZE_SHRINK_BEGIN
	name_label.add_theme_font_size_override("font_size", 18)

	var desc_label := Label.new()
	var description := world_dict.get("description", "")
	desc_label.text = description if description != "" else "No description."
	desc_label.autowrap_mode = TextServer.AUTOWRAP_WORD
	desc_label.size_flags_horizontal = Control.SIZE_FILL
	desc_label.size_flags_vertical = Control.SIZE_EXPAND_FILL
	desc_label.add_theme_font_size_override("font_size", 14)
	desc_label.add_theme_color_override("font_color", Color(0.7, 0.7, 0.7, 1.0))

	var meta_label := Label.new()
	var visibility := world_dict.get("visibility", "public")
	var created := world_dict.get("created_at", "")
	meta_label.text = "Visibility: %s%s" % [visibility, " | Created: " + created if created != "" else ""]
	meta_label.autowrap_mode = TextServer.AUTOWRAP_WORD
	meta_label.size_flags_horizontal = Control.SIZE_FILL
	meta_label.size_flags_vertical = Control.SIZE_SHRINK_BEGIN
	meta_label.add_theme_font_size_override("font_size", 12)
	meta_label.add_theme_color_override("font_color", Color(0.5, 0.5, 0.5, 1.0))

	card.add_child(name_label)
	card.add_child(desc_label)
	card.add_child(meta_label)

	# Subtle background for the card
	var bg := ColorRect.new()
	bg.color = Color(0.15, 0.15, 0.15, 1.0)
	bg.size_flags_horizontal = Control.SIZE_FILL
	bg.size_flags_vertical = Control.SIZE_FILL
	bg.custom_minimum_size = Vector2(0, 80)
	card.add_child(bg)
	card.move_child(bg, 0)

	return card