class_name UploadPopup
extends BasePopup
## Adds a new soundtrack to the server from a folder: picked with Add soundtrack… in the
## statistics, or dropped on the window.
##
## Lists the folder's songs (see [UploadFolder]), lets the name be changed, and uploads
## the songs one at a time with a progress bar. A song that fails is sent again a couple
## of times before the upload is cancelled. The server then adds the soundtrack at once,
## without a sync.

## Emitted when the server has added the soundtrack.
signal soundtrack_added(soundtrack: SoundtrackWithSongList)

## How many times a song that failed is sent again before the upload is given up.
const RETRIES: int = 2

## The folder shown.
var folder: UploadFolder

# The upload on the server, while there is one
var _upload_id: String = ""
# The song being sent, and how often it failed
var _next: int = 0
var _failures: int = 0
var _uploading: bool = false

@onready var name_field: LineEdit = %NameField
@onready var choose_folder_button: Button = %ChooseFolderButton
@onready var folder_label: Label = %FolderLabel
@onready var song_list: VBoxContainer = %SongList
@onready var summary_label: Label = %SummaryLabel
@onready var upload_progress: ProgressBar = %UploadProgress
@onready var status_label: Label = %StatusLabel
@onready var cancel_button: Button = %CancelButton
@onready var upload_button: Button = %UploadButton
@onready var folder_dialog: FileDialog = %FolderDialog


func _ready() -> void:
	choose_folder_button.pressed.connect(folder_dialog.popup_centered)
	folder_dialog.dir_selected.connect(show_folder)
	cancel_button.pressed.connect(close)
	upload_button.pressed.connect(upload)
	name_field.text_changed.connect(func(_text: String) -> void: _update_buttons())
	name_field.text_submitted.connect(func(_text: String) -> void: upload())


## Asks for a folder, then shows it.
func choose_folder() -> void:
	folder_dialog.popup_centered()


## Lists the songs in the folder at [param path] and opens the popup.
func show_folder(path: String) -> void:
	folder = UploadFolder.scan(path)
	name_field.text = folder.suggested_name
	folder_label.text = "From " + short_path(folder.path)
	folder_label.tooltip_text = folder.path
	_fill_song_list()
	summary_label.text = summary_text(folder)
	upload_progress.visible = false
	status_label.visible = false
	upload_button.visible = true
	cancel_button.text = "Cancel"
	if Settings.is_offline():
		_show_status("Adding a soundtrack needs the server, not a music folder.")
	elif !folder.has_songs():
		_show_status("There are no MP3 files in %s." % folder.path.get_file())
	_set_uploading(false)
	open()


## Starts uploading the songs as a soundtrack with the name in the name field.
func upload() -> void:
	if upload_button.disabled || !upload_button.visible:
		return
	if Settings.currently_syncing:
		_show_status("The server is syncing. Try again when it is done.")
		return
	_set_uploading(true)
	upload_progress.max_value = folder.songs.size()
	upload_progress.value = 0
	upload_progress.visible = true
	_show_status("Starting the upload…")
	MusicServerClient.start_upload(UploadFolder.clean_name(name_field.text), _on_started,
			func() -> void: _stop("Could not start the upload"))


## Stops an upload under way, and closes the popup.
func close() -> void:
	if _uploading:
		_uploading = false
		_cancel_on_server()
	super()


## The last two parts of [param path], e.g. "…/Soundtracks/Chrono Trigger", since the
## start of a long path says the least.
static func short_path(path: String) -> String:
	var parts: PackedStringArray = path.replace("\\", "/").split("/", false)
	if parts.size() <= 2:
		return path
	return "…/" + "/".join(parts.slice(-2))


## "30 songs, 245.1 MB", and how many files are left out.
static func summary_text(shown: UploadFolder) -> String:
	var text: String = "%d %s, %s" % [shown.songs.size(),
			"song" if shown.songs.size() == 1 else "songs",
			SettingsPopup.size_text(shown.total_size)]
	if !shown.skipped.is_empty():
		text += ". %d %s left out: only MP3 files can be uploaded." % [shown.skipped.size(),
				"file" if shown.skipped.size() == 1 else "files"]
	return text


func _on_started(upload_info: Upload) -> void:
	if !_uploading:
		# Closed while the server was answering
		MusicServerClient.cancel_upload(upload_info.id)
		return
	_upload_id = upload_info.id
	_next = 0
	_failures = 0
	_send_next()


func _send_next() -> void:
	if !_uploading:
		return
	if _next >= folder.songs.size():
		_show_status("Adding the soundtrack…")
		MusicServerClient.finish_upload(_upload_id, _on_finished,
				func() -> void: _stop("Could not add the soundtrack"))
		return
	var song: Dictionary = folder.songs[_next]
	_show_status("Uploading %d of %d: %s" % [_next + 1, folder.songs.size(), song.name])
	# One song at a time, so only one is held in memory
	var bytes: PackedByteArray = FileAccess.get_file_as_bytes(song.path)
	if bytes.is_empty():
		MusicServerClient.last_error = "the file could not be read"
		_stop("Could not upload " + song.name)
		return
	MusicServerClient.upload_song(_upload_id, song.name, bytes, _on_song_sent, _on_song_failed)


func _on_song_sent() -> void:
	_next += 1
	_failures = 0
	upload_progress.value = _next
	_send_next()


func _on_song_failed() -> void:
	_failures += 1
	if _failures <= RETRIES && _uploading:
		_send_next()
		return
	_stop("Could not upload " + folder.songs[_next].name)


func _on_finished(soundtrack: SoundtrackWithSongList) -> void:
	_upload_id = ""
	_uploading = false
	upload_progress.value = upload_progress.max_value
	_show_status("Added %s with %d %s." % [soundtrack.name, soundtrack.songs.size(),
			"song" if soundtrack.songs.size() == 1 else "songs"])
	upload_button.visible = false
	cancel_button.text = "Close"
	_set_uploading(false)
	soundtrack_added.emit(soundtrack)


# Gives up, says why with the server's reason, and removes what was uploaded
func _stop(what: String) -> void:
	var reason: String = MusicServerClient.last_error
	_cancel_on_server()
	_uploading = false
	upload_progress.visible = false
	_set_uploading(false)
	_show_status("%s: %s." % [what,
			reason if !reason.is_empty() else "the server could not be reached"])


func _cancel_on_server() -> void:
	if !_upload_id.is_empty():
		MusicServerClient.cancel_upload(_upload_id)
		_upload_id = ""


func _set_uploading(uploading: bool) -> void:
	_uploading = uploading
	name_field.editable = !uploading
	choose_folder_button.disabled = uploading
	_update_buttons()


func _update_buttons() -> void:
	upload_button.disabled = _uploading || folder == null || !folder.has_songs() \
			|| UploadFolder.clean_name(name_field.text).is_empty() || Settings.is_offline()


func _fill_song_list() -> void:
	Settings.delete_children(song_list)
	var row: int = 0
	for song: Dictionary in folder.songs:
		song_list.add_child(ListRow.create("%s  ·  %s" % [song.name,
				SettingsPopup.size_text(song.size)], row, &"TextMedium"))
		row += 1
	for skipped: String in folder.skipped:
		var list_row: ListRow = ListRow.create("%s  ·  not MP3, left out" % skipped, row,
				&"TextMedium")
		list_row.label.self_modulate.a = 0.5
		song_list.add_child(list_row)
		row += 1


func _show_status(message: String) -> void:
	status_label.text = message
	status_label.visible = true