class_name AssetSelector
extends PopupPanel

signal item_selected(entry: Dictionary)
signal cancelled()
signal browse_requested()
signal refresh_requested()
signal make_artwork_requested()
signal edit_scenery_requested()

const COLUMNS := 4
const ROWS := 3
const PAGE_SIZE := COLUMNS * ROWS

const CELL_MIN_SIZE := Vector2(190.0, 220.0)
const THUMB_SIZE := Vector2(156.0, 156.0)
const ASSET_CARD := preload("res://scripts/shared/ui/asset_card.gd")
const BACKGROUND_CARD_PREVIEW := preload("res://scripts/stage/scenery/stage_background_card_preview.gd")
const STARTER_CARD_PREVIEW := preload("res://scripts/stage/scenery/stage_starter_card_preview.gd")

var kind: String = ""

var _entries: Array[Dictionary] = []
var _page: int = 0
var _thumbnails: Dictionary = {}
var _cell_texrects: Dictionary = {}
var _placeholder_tex: ImageTexture = null
var _ui_font: Font = null
var _emoji_font: Font = null
var _sandbox_theme: Variant = null
var _gallery_tab: String = "backgrounds"
var _tag_id: String = "all"
var _current_sky_id: String = ""
var _sky_card_group: ButtonGroup

@onready var _title_label: Label = %TitleLabel
@onready var _grid: GridContainer = %GridContainer
@onready var _empty_label: Label = %EmptyLabel
@onready var _page_label: Label = %PageLabel
@onready var _prev_button: Button = %PrevButton
@onready var _next_button: Button = %NextButton
@onready var _browse_button: Button = %BrowseButton
@onready var _refresh_button: Button = %RefreshButton
@onready var _close_button: Button = %CloseButton
@onready var _tabs: HBoxContainer = %GalleryTabs
@onready var _backgrounds_tab: Button = %BackgroundsTab
@onready var _artwork_tab: Button = %ArtworkTab
@onready var _tag_filter: OptionButton = %TagFilter
@onready var _make_artwork_button: Button = %MakeArtworkButton
@onready var _edit_scenery_button: Button = %EditSceneryButton


func _ready() -> void:
	exclusive = true
	if _tag_filter.item_count == 0:
		for label: String in ["All artwork", "Nature", "Buildings", "Walls", "Roads", "Objects"]:
			_tag_filter.add_item(label)
	_prev_button.pressed.connect(_on_prev)
	_next_button.pressed.connect(_on_next)
	_browse_button.pressed.connect(func() -> void: browse_requested.emit())
	_refresh_button.pressed.connect(func() -> void: refresh_requested.emit())
	_close_button.pressed.connect(func() -> void: cancelled.emit())
	_backgrounds_tab.pressed.connect(func() -> void: _set_gallery_tab("backgrounds"))
	_artwork_tab.pressed.connect(func() -> void: _set_gallery_tab("artwork"))
	_tag_filter.item_selected.connect(_on_tag_filter_selected)
	_make_artwork_button.pressed.connect(func() -> void: make_artwork_requested.emit())
	_edit_scenery_button.pressed.connect(func() -> void: edit_scenery_requested.emit())
	get_tree().root.size_changed.connect(_on_root_size_changed)


func _on_root_size_changed() -> void:
	if visible:
		popup_centered()


func open(p_kind: String, entries: Array[Dictionary], current_sky_id: String = "") -> void:
	kind = p_kind
	_current_sky_id = current_sky_id if kind == "scenery" else ""
	_title_label.text = "Choose Your Stickman" if kind == "stickman" else ("Choose Scenery" if kind == "scenery" else ("Choose a starter scene" if kind == "starters" else "Choose a Prop"))
	_tabs.visible = kind == "scenery"
	_tag_filter.visible = false
	_make_artwork_button.visible = false
	_edit_scenery_button.visible = false
	_browse_button.visible = kind == "stickman" or kind == "prop" or kind == "scenery"
	_refresh_button.visible = kind == "stickman" or kind == "prop" or kind == "scenery"
	_empty_label.text = "No scenery found. Choose Make artwork to draw a new piece." if kind == "scenery" else ("No props found. Browse for a .prop file." if kind == "prop" else ("No starter scenes are available." if kind == "starters" else "No stickmen found."))
	_gallery_tab = "backgrounds"
	_tag_id = "all"
	_backgrounds_tab.set_pressed_no_signal(true)
	_artwork_tab.set_pressed_no_signal(false)
	_tag_filter.select(0)
	set_entries(entries)
	if kind == "scenery":
		_set_gallery_tab("backgrounds")
	popup_centered()


func set_entries(entries: Array[Dictionary]) -> void:
	_entries = entries
	_thumbnails.clear()
	_cell_texrects.clear()
	_page = 0
	_rebuild()


func set_thumbnail(entry: Dictionary, tex: Texture2D) -> void:
	var key := _entry_key(entry)
	_thumbnails[key] = tex
	if _cell_texrects.has(key):
		(_cell_texrects[key] as TextureRect).texture = tex


func set_current_sky(sky_id: StringName) -> void:
	var next_id: String = String(sky_id)
	if kind != "scenery" or _current_sky_id == next_id:
		return
	_current_sky_id = next_id
	if _gallery_tab == "backgrounds":
		_rebuild()


func close() -> void:
	hide()


func apply_font(ui_font: Font, emoji_font: Font) -> void:
	_ui_font = ui_font
	_emoji_font = emoji_font
	var controls: Array = [
		_title_label, _empty_label, _page_label,
		_prev_button, _next_button, _browse_button, _refresh_button, _close_button,
	]
	for c: Control in controls:
		_apply_font_to(c)

func apply_theme(theme: Variant) -> void:
	_sandbox_theme = theme
	if theme != null:
		self.theme = theme.control_theme()
		add_theme_stylebox_override("panel", theme.stylebox("popups.asset_selector"))
		var cell_size: Variant = theme.value("popups.asset_selector.cell_size", CELL_MIN_SIZE)
		if cell_size is Array and (cell_size as Array).size() == 2:
			_cell_min_size = Vector2(float(cell_size[0]), float(cell_size[1]))
		var thumbnail_size: Variant = theme.value("popups.asset_selector.thumbnail_size", THUMB_SIZE)
		if thumbnail_size is Array and (thumbnail_size as Array).size() == 2:
			_thumbnail_size = Vector2(float(thumbnail_size[0]), float(thumbnail_size[1]))

var _cell_min_size: Vector2 = CELL_MIN_SIZE
var _thumbnail_size: Vector2 = THUMB_SIZE


func _unhandled_input(event: InputEvent) -> void:
	if visible and event is InputEventKey:
		var key := event as InputEventKey
		if key.pressed and not key.echo and key.keycode == KEY_ESCAPE:
			get_viewport().set_input_as_handled()
			cancelled.emit()


static func page_bounds(total: int, page: int, page_size: int = PAGE_SIZE) -> Dictionary:
	var page_count := maxi(1, int(ceil(float(total) / float(page_size))))
	var start := page * page_size
	if start >= total:
		start = 0
	var end := mini(start + page_size, total)
	return { "start": start, "end": end, "total": total, "page_count": page_count }


func _entry_key(entry: Dictionary) -> String:
	if kind == "stickman":
		return String(entry.get("path", ""))
	return String(entry.get("id", ""))


func _on_tag_filter_selected(index: int) -> void:
	var ids: Array[String] = ["all", "nature", "buildings", "walls", "roads", "objects"]
	_tag_id = ids[clampi(index, 0, ids.size() - 1)]
	_page = 0
	_rebuild()


func _set_gallery_tab(tab: String) -> void:
	_gallery_tab = tab
	_backgrounds_tab.set_pressed_no_signal(tab == "backgrounds")
	_artwork_tab.set_pressed_no_signal(tab == "artwork")
	_tag_filter.visible = kind == "scenery" and tab == "artwork"
	_make_artwork_button.visible = kind == "scenery" and tab == "artwork"
	_edit_scenery_button.visible = kind == "scenery"
	_browse_button.visible = kind == "stickman" or kind == "prop" or (kind == "scenery" and tab == "artwork")
	_refresh_button.visible = kind == "stickman" or kind == "prop" or (kind == "scenery" and tab == "artwork")
	_empty_label.text = "No artwork in this group yet." if tab == "artwork" else "Choose a Sky look or wall finish."
	_page = 0
	_rebuild()


func _filtered_entries() -> Array[Dictionary]:
	if kind != "scenery":
		return _entries
	var filtered: Array[Dictionary] = []
	for entry: Dictionary in _entries:
		if String(entry.get("gallery_tab", "artwork")) != _gallery_tab:
			continue
		if _gallery_tab == "artwork" and _tag_id != "all":
			var tags: Array = entry.get("tags", []) as Array
			if not tags.has(_tag_id):
				continue
		filtered.append(entry)
	return filtered


func _on_prev() -> void:
	if _page > 0:
		_page -= 1
		_rebuild()


func _on_next() -> void:
	if (_page + 1) * PAGE_SIZE < _filtered_entries().size():
		_page += 1
		_rebuild()


func _page_count() -> int:
	var entries: Array[Dictionary] = _filtered_entries()
	if entries.is_empty():
		return 1
	return int(ceil(float(entries.size()) / float(PAGE_SIZE)))


func _rebuild() -> void:
	_sky_card_group = ButtonGroup.new()
	for c: Node in _grid.get_children():
		c.queue_free()
	_cell_texrects.clear()
	var filtered: Array[Dictionary] = _filtered_entries()
	_empty_label.visible = filtered.is_empty()
	_grid.visible = not filtered.is_empty()
	var total := _page_count()
	var single := total <= 1
	_prev_button.visible = not single
	_next_button.visible = not single
	_page_label.visible = not single
	_prev_button.disabled = _page <= 0
	_next_button.disabled = (_page + 1) * PAGE_SIZE >= filtered.size()
	_page_label.text = "Page %d/%d" % [_page + 1, total]
	if filtered.is_empty():
		return
	var bounds := page_bounds(filtered.size(), _page)
	for i: int in range(int(bounds["start"]), int(bounds["end"])):
		_grid.add_child(_build_cell(filtered[i]))


func _build_cell(entry: Dictionary) -> Control:
	var key := _entry_key(entry)
	var cell: Variant = ASSET_CARD.new()
	# Selector cells inherit the popup theme. Avoid a per-card state override so
	# opening a selector never implies that one asset is pre-selected.
	var categories: Array = entry.get("tags", []) as Array
	var category: String = ", ".join(PackedStringArray(categories)) if not categories.is_empty() else String(entry.get("category", entry.get("material_label", "")))
	var card_size: Vector2 = _cell_min_size
	var thumb_size: Vector2 = _thumbnail_size
	if kind == "starters":
		card_size.y = maxf(card_size.y, 248.0)
		thumb_size = Vector2(128.0, 128.0)
	var card_payload: Dictionary = {"placement_id": _entry_key(entry), "label": String(entry.get("name", entry.get("id", ""))), "icon": String(entry.get("icon", "")), "category": category, "description": String(entry.get("description", "")), "thumbnail_size": thumb_size}
	if entry.has("background_kind"):
		card_payload["background_kind"] = entry["background_kind"]
		card_payload["finish_id"] = entry.get("finish_id", "")
		card_payload["id"] = entry.get("id", "")
	var is_sky_choice: bool = String(entry.get("background_kind", "")) == "sky"
	var is_current_sky: bool = is_sky_choice and String(entry.get("id", "")) == _current_sky_id
	if is_current_sky:
		card_payload["status"] = "Current Sky"
		card_payload["status_color"] = _theme_color("mode_colors.edit", Color("#22C6FF"))
	cell.configure(card_payload, _thumbnails.get(key, null), null)
	cell.custom_minimum_size = card_size
	cell.focus_mode = Control.FOCUS_ALL
	cell.activated.connect(func(_payload: Dictionary) -> void: _on_cell_pressed(entry))
	if is_sky_choice:
		cell.button_group = _sky_card_group
		cell.set_selected(is_current_sky, _theme_color("stage_panels.choice.selected_surface", Color("#12394A")), _theme_color("mode_colors.edit", Color("#22C6FF")))
	var tex: Texture2D = _thumbnails.get(key, null)
	if kind == "starters":
		var preview: Control = STARTER_CARD_PREVIEW.new() as Control
		preview.call("configure", entry)
		cell.set_preview_control(preview)
	elif entry.has("background_kind"):
		var preview: StageBackgroundCardPreview = BACKGROUND_CARD_PREVIEW.new() as StageBackgroundCardPreview
		preview.configure(entry)
		cell.set_preview_control(preview)
	else:
		cell.set_thumbnail(tex if tex != null else _get_placeholder())
		_cell_texrects[key] = cell.thumbnail_rect()

	return cell


func _theme_color(path: String, fallback: Color) -> Color:
	if _sandbox_theme != null:
		return _sandbox_theme.color(path, fallback)
	return fallback


func _on_cell_pressed(entry: Dictionary) -> void:
	item_selected.emit(entry)


func _apply_font_to(c: Control) -> void:
	if c == null:
		return
	if _ui_font != null:
		c.add_theme_font_override("font", _ui_font)
	elif _emoji_font != null:
		c.add_theme_font_override("font", _emoji_font)


func _get_placeholder() -> ImageTexture:
	if _placeholder_tex == null:
		var img := Image.create(int(_thumbnail_size.x), int(_thumbnail_size.y), false, Image.FORMAT_RGBA8)
		img.fill(Color(0.16, 0.16, 0.16, 1.0))
		_placeholder_tex = ImageTexture.create_from_image(img)
	return _placeholder_tex