extends Library

const ItchClient := preload("res://plugins/itch/core/itch_client.gd")
const _apps_cache_file: String = "apps.json"

@onready var itch: ItchClient = get_tree().get_first_node_in_group("itch_client")


func _ready() -> void:
	super()
	library_id = "itch"
	logger_name = "itch"
	logger = Log.get_logger(logger_name, log_level)
	logger.info("itch.io library loaded")
	itch.logged_in.connect(_on_logged_in)
	itch.install_progressed.connect(_on_install_progressed)


func get_library_launch_items() -> Array[LibraryLaunchItem]:
	return await _load_library(Cache.FLAGS.LOAD | Cache.FLAGS.SAVE)


func install_to(item: LibraryLaunchItem, _location: InstallLocation = null, _options: Dictionary = {}) -> void:
	var game := (item.metadata.get("game", {}) as Dictionary)
	itch.install(game)


func update(item: LibraryLaunchItem) -> void:
	var game := (item.metadata.get("game", {}) as Dictionary)
	itch.install(game, item.provider_app_id)


func uninstall(item: LibraryLaunchItem) -> void:
	itch.uninstall(item.provider_app_id)


## itch.io's CheckUpdate call is async (and rate-limited), so we don't poll it
## synchronously here. LibraryManager is expected to periodically call
## get_library_launch_items() again, which re-fetches from butlerd's cache.
func has_update(_item: LibraryLaunchItem) -> bool:
	return false


func _on_logged_in(status: ItchClient.LOGIN_STATUS, _profile: Dictionary) -> void:
	if status != ItchClient.LOGIN_STATUS.OK:
		return
	logger.info("Logged in. Refreshing itch.io library.")
	var items: Array = await _load_library(Cache.FLAGS.SAVE)
	for i in items:
		var item: LibraryLaunchItem = i
		if not library_manager.has_app(item.name):
			logger.debug("App '" + item.name + "' was not loaded. Reloading library.")
			library_manager.reload_library()
			return


## Re-emits itch.io's raw (id, current, total) install progress under the
## base [Library] signal contract (item, percent_completed) so the UI's
## generic install-progress widgets pick it up regardless of provider.
## TODO: verify the exact LibraryManager lookup method/key for resolving a
## provider_app_id back to its LibraryLaunchItem (this plugin was written
## against the public Library/LibraryLaunchItem API, but LibraryManager's
## internals weren't available while writing this) and wire the emit below
## through it instead of dropping the notification.
func _on_install_progressed(_id: String, _current: int, _total: int) -> void:
	pass


## Builds the full itch.io library: owned games merged with install state
## from Fetch.Caves. Uses the standard Cache system so we don't hammer
## butlerd (and, transitively, the itch.io API) on every library refresh.
func _load_library(caching_flags: int = Cache.FLAGS.LOAD | Cache.FLAGS.SAVE) -> Array[LibraryLaunchItem]:
	if caching_flags & Cache.FLAGS.LOAD and Cache.is_cached(_cache_dir, _apps_cache_file):
		var json_items = Cache.get_json(_cache_dir, _apps_cache_file)
		if json_items != null:
			logger.info("itch.io apps found in cache. Using cache.")
			var items := [] as Array[LibraryLaunchItem]
			for i in json_items:
				items.append(LibraryLaunchItem.from_dict(i))
			return items

	if not itch.is_logged_in:
		logger.info("itch.io client is not logged in yet.")
		return []

	logger.info("Fetching itch.io library...")
	var owned: Array = await itch.get_owned_games()
	var caves: Array = await itch.get_caves()

	var caves_by_game_id := {}
	for c in caves:
		var cave: Dictionary = c
		var game_id: int = cave.get("game", {}).get("id", 0)
		caves_by_game_id[game_id] = cave

	var items := [] as Array[LibraryLaunchItem]
	for o in owned:
		var owned_entry: Dictionary = o
		var game: Dictionary = owned_entry.get("game", {})
		if game.is_empty():
			continue
		# Only surface actual games (itch.io also hosts tools, assets,
		# soundtracks, comics, etc. under the same ownership API).
		if game.get("classification", "game") != "game":
			continue

		var game_id: int = game.get("id", 0)
		var cave: Dictionary = caves_by_game_id.get(game_id, {})

		var item := LibraryLaunchItem.new()
		item.provider_app_id = cave.get("id", "")
		item.name = game.get("title", "Unknown itch.io game")
		item.tags = ["itch"]
		item.categories = ["Game"]
		item.installed = not cave.is_empty()
		item.metadata = {"game": game}

		if not cave.is_empty():
			var install_folder: String = cave.get("installInfo", {}).get("installFolder", "")
			var exe := _find_executable(install_folder)
			item.command = exe
			item.args = []
			item.cwd = install_folder

		items.append(item)

	if caching_flags & Cache.FLAGS.SAVE:
		logger.debug("Saving itch.io apps to cache.")
		var json_items := []
		for i in items:
			var item: LibraryLaunchItem = i
			json_items.append(item.to_dict())
		if Cache.save_json(_cache_dir, _apps_cache_file, json_items) != OK:
			logger.warn("Unable to save itch.io apps cache")

	return items


## Best-effort discovery of the game's launch executable inside its install
## folder. butlerd doesn't hand back a ready-to-exec command the way a
## "gog://" or "steam://" URI does, so we look at what's actually on disk.
## TODO: parse .itch/receipt.json.gz for the authoritative launch target
## and any declared manifest Actions instead of guessing.
func _find_executable(install_folder: String) -> String:
	if install_folder == "":
		return ""
	var out := []
	OS.execute("bash", [
		"-c",
		"find " + install_folder.c_escape() + " -maxdepth 2 -type f -executable | head -n 1"
	], out)
	if out.is_empty():
		return ""
	return (out[0] as String).strip_edges()