Initial commit

addons/cgheven/core/downloader.gd

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+@tool
+extends Node
+class_name CghDownloader
+## Threaded file download with polled progress (Godot has no progress signal).
+## Emits progress every frame while a download is in flight.
+
+signal progress(pct: float, downloaded: int, total: int)
+signal finished(path: String)
+signal failed(message: String)
+
+var _http: HTTPRequest
+var _active := false
+var _dest := ""
+var _last_got := 0      # bytes seen last frame — to detect a dead/stalled connection
+var _stall := 0.0       # seconds with zero new bytes
+const STALL_LIMIT := 30.0   # a hung download must not block every later one forever
+
+func _ready() -> void:
+	_http = HTTPRequest.new()
+	_http.use_threads = true
+	add_child(_http)
+	_http.request_completed.connect(_on_done)
+
+func download(url: String, filename: String, headers := PackedStringArray()) -> void:
+	if _active:
+		failed.emit("A download is already in progress.")
+		return
+	CghConfig.ensure_dirs()
+	# Save into the SHARED CGHEVEN folder so AE/Blender/etc. see it too (file scanner).
+	var dir := CghConfig.primary_download_dir()
+	DirAccess.make_dir_recursive_absolute(dir)
+	_dest = dir.path_join(CghConfig.safe_download_name(filename))
+	# Clear any orphaned/stuck request first (mirrors api_client) so a previously hung
+	# download that left the node "processing" can't block this new one from starting.
+	_http.cancel_request()
+	_http.download_file = _dest
+	var err := _http.request(url, headers, HTTPClient.METHOD_GET)
+	if err != OK:
+		failed.emit("Download could not start (err %d)" % err)
+		return
+	_active = true
+	_last_got = 0
+	_stall = 0.0
+	set_process(true)
+
+func _process(dt: float) -> void:
+	if not _active:
+		set_process(false)
+		return
+	var got := _http.get_downloaded_bytes()
+	var total := _http.get_body_size()   # -1 on chunked / no Content-Length
+	# Dead-connection guard: if no new bytes arrive for STALL_LIMIT seconds, give up so
+	# the download queue isn't blocked forever (a hung request never fires _on_done).
+	if got > _last_got:
+		_last_got = got
+		_stall = 0.0
+	else:
+		_stall += dt
+		if _stall >= STALL_LIMIT:
+			_http.cancel_request()
+			_active = false
+			set_process(false)
+			failed.emit("Download stalled (no data for %ds) — check your connection and retry." % int(STALL_LIMIT))
+			return
+	if total > 0:
+		progress.emit(float(got) / float(total) * 100.0, got, total)
+	else:
+		progress.emit(-1.0, got, -1)     # indeterminate -> spinner
+
+func cancel() -> void:
+	if _active:
+		_http.cancel_request()
+		_active = false
+		set_process(false)
+
+func _on_done(result: int, code: int, _h: PackedStringArray, _b: PackedByteArray) -> void:
+	_active = false
+	set_process(false)
+	if result != HTTPRequest.RESULT_SUCCESS or code < 200 or code >= 300:
+		var hint := ""
+		if code == 401 or code == 403:
+			hint = " — access denied (file link may be expired/invalid on the server)"
+		elif code == 404:
+			hint = " — file not found on the server"
+		elif result != HTTPRequest.RESULT_SUCCESS:
+			hint = " — network/connection issue"
+		failed.emit("Download failed for %s%s [result %d, HTTP %d]" % [_dest.get_file(), hint, result, code])
+		return
+	CghDownloads.mark_saved(_dest.get_file())
+	finished.emit(_dest)