Download itch.io cover art into OGPU's local boxart dir so games show real covers instead of the placeholder

core/library_itch.gd

@@ -77,6 +77,7 @@ func _load_library(caching_flags: int = Cache.FLAGS.LOAD | Cache.FLAGS.SAVE) ->
 			var items := [] as Array[LibraryLaunchItem]
 			for i in json_items:
 				items.append(LibraryLaunchItem.from_dict(i))
+			_queue_boxart(items)
 			return items
 
 	if not itch.is_logged_in:
@@ -133,9 +134,129 @@ func _load_library(caching_flags: int = Cache.FLAGS.LOAD | Cache.FLAGS.SAVE) ->
 		if Cache.save_json(_cache_dir, _apps_cache_file, json_items) != OK:
 			logger.warn("Unable to save itch.io apps cache")
 
+	_queue_boxart(items)
+
 	return items
 
 
+## Queues background downloads of each game's cover art into OGPU's local
+## boxart directory (user://boxart/local/). The built-in "local" BoxArtProvider
+## picks those files up by <game name>-<layout>.png, so games show their real
+## cover instead of the placeholder. Covers are only downloaded once (the task
+## bails out if a layout file already exists).
+func _queue_boxart(items: Array) -> void:
+	for i in items:
+		var item: LibraryLaunchItem = i
+		var game: Dictionary = item.metadata.get("game", {})
+		var title: String = game.get("title", "")
+		var cover_url: String = game.get("coverUrl", "")
+		if title.is_empty() or cover_url.is_empty():
+			continue
+		if FileAccess.file_exists("/".join([_boxart_dir(), title + "-portrait.png"])):
+			continue
+		itch.thread_group.scheduled_exec(_ensure_boxart.bind(game), 0)
+
+
+## Downloads the given game's cover (blocking, runs on the shared thread) and
+## writes it to every boxart layout. itch.zone only serves one fixed landscape
+## image per game, and OGPU's boxart slots all keep-aspect (scale + crop), so a
+## single image is reused for portrait, landscape, banner and logo.
+func _ensure_boxart(game: Dictionary) -> void:
+	var title: String = game.get("title", "")
+	var cover_url: String = game.get("coverUrl", "")
+	if title.is_empty() or cover_url.is_empty():
+		return
+	var dir := _boxart_dir()
+	if FileAccess.file_exists("/".join([dir, title + "-portrait.png"])):
+		return
+
+	var body := _download_cover(cover_url)
+	if body.is_empty():
+		logger.warn("Unable to download cover art for '" + title + "'")
+		return
+	if not _is_raster_image(body):
+		# OGPU's local provider only loads png/jpg; animated gif covers (rare)
+		# can't be rendered, so skip them rather than write an unloadable file.
+		logger.warn("Skipping unsupported cover format for '" + title + "'")
+		return
+
+	DirAccess.make_dir_recursive_absolute(dir)
+	for layout in ["portrait", "landscape", "banner", "logo"]:
+		var path := "/".join([dir, title + "-" + layout + ".png"])
+		var file := FileAccess.open(path, FileAccess.WRITE)
+		if file:
+			file.store_buffer(body)
+			file.close()
+	logger.info("Downloaded boxart for '" + title + "'")
+
+
+func _boxart_dir() -> String:
+	return ProjectSettings.globalize_path("user://boxart/local")
+
+
+## Blocking HTTPS GET of a single cover image, for use on a background thread.
+func _download_cover(url: String) -> PackedByteArray:
+	var parts := url.split("/")
+	var use_tls := parts[0] == "https:"
+	var http := HTTPClient.new()
+	var err: int = http.connect_to_host(parts[2], 443 if use_tls else 80, TLSOptions.client() if use_tls else null)
+	if err != OK:
+		return PackedByteArray()
+	var deadline := Time.get_ticks_msec() + 15000
+	while http.get_status() == HTTPClient.STATUS_CONNECTING or http.get_status() == HTTPClient.STATUS_RESOLVING:
+		http.poll()
+		if Time.get_ticks_msec() > deadline:
+			http.close()
+			return PackedByteArray()
+		OS.delay_msec(50)
+	if http.get_status() != HTTPClient.STATUS_CONNECTED:
+		http.close()
+		return PackedByteArray()
+
+	http.request(HTTPClient.METHOD_GET, "/" + "/".join(parts.slice(3)), PackedStringArray())
+	deadline = Time.get_ticks_msec() + 15000
+	while http.get_status() == HTTPClient.STATUS_REQUESTING:
+		http.poll()
+		if Time.get_ticks_msec() > deadline:
+			http.close()
+			return PackedByteArray()
+		OS.delay_msec(10)
+
+	var body := PackedByteArray()
+	while http.get_status() == HTTPClient.STATUS_BODY:
+		http.poll()
+		var chunk: PackedByteArray = http.read_response_body_chunk()
+		if chunk.is_empty():
+			if Time.get_ticks_msec() > deadline:
+				http.close()
+				return PackedByteArray()
+			OS.delay_msec(10)
+			continue
+		body.append_array(chunk)
+
+	var code: int = http.get_response_code()
+	http.close()
+	if code != 200:
+		return PackedByteArray()
+	return body
+
+
+## Returns true if the bytes look like a PNG or JPEG (the only formats OGPU's
+## local boxart provider can load).
+func _is_raster_image(body: PackedByteArray) -> bool:
+	if body.size() < 12:
+		return false
+	var png_magic := [0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a]
+	var is_png := true
+	for i in png_magic.size():
+		if body[i] != png_magic[i]:
+			is_png = false
+			break
+	if is_png:
+		return true
+	return body[0] == 0xff and body[1] == 0xd8 and body[2] == 0xff
+
+
 ## 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.