#!/usr/bin/python3

from . import WBZM3UData


class WobuzzM3U:
    sort_orders = {
        "Title": WBZM3UData.SortOrder.track_title,
        "Artist": WBZM3UData.SortOrder.track_artist,
        "Album": WBZM3UData.SortOrder.track_album,
        "Genre": WBZM3UData.SortOrder.track_genre,
        "Custom": WBZM3UData.SortOrder.custom_sorting
    }

    sort_order_names = {
        WBZM3UData.SortOrder.track_title: "Title",
        WBZM3UData.SortOrder.track_artist: "Artist",
        WBZM3UData.SortOrder.track_album: "Album",
        WBZM3UData.SortOrder.track_genre: "Genre",
        WBZM3UData.SortOrder.custom_sorting: "Custom"
    }

    def __init__(self, filename: str):
        self.filename = filename

    def parse_line(self, line: str) -> WBZM3UData | None:
        if line.startswith("#"):  # comments and EXTM3U/WOBUZZM3U
            if line.startswith("#WOBUZZM3U"):
                return WBZM3UData.Header()

            elif line.startswith("#SORT: "):  # sort
                sorting_params = line[6:]  # delete "#SORT: " from the line

                sorting = sorting_params.split(", ")  # split into the sort column specifier and the sort order
                # e.g. ["Title", "Ascending"]

                if not sorting[0] in self.sort_orders:
                    return None

                sort_by = self.sort_orders[sorting[0]]
                order = sorting[1] == "Ascending"

                return WBZM3UData.SortOrder(sort_by, order)

            elif line.startswith("#TRACK_TITLE: "):
                return WBZM3UData.TrackMetadata.TrackTitle(line[14:])

            elif line.startswith("#TRACK_ARTIST: "):
                return WBZM3UData.TrackMetadata.TrackArtist(line[15:])

            elif line.startswith("#TRACK_ALBUM: "):
                return WBZM3UData.TrackMetadata.TrackAlbum(line[14:])

            return None

        elif line.startswith("http"):
            return WBZM3UData.URL("URLs currently aren't supported.")

        # line contains a path
        return WBZM3UData.Path(line)

    def assemble_line(self, data: WBZM3UData) -> str | None:
        if isinstance(data, WBZM3UData.Header):
            return "#WOBUZZM3U\n"

        if isinstance(data, WBZM3UData.Path):
            return f"{data}\n"

        if isinstance(data, WBZM3UData.URL):
            return None

        if isinstance(data, WBZM3UData.SortOrder):
            direction = "Ascending" if data.ascending else "Descending"

            return f"#SORT: {self.sort_order_names[data.sort_by]}, {direction}\n"

        if isinstance(data, WBZM3UData.TrackMetadata.TrackTitle):
            return f"#TRACK_TITLE: {data}\n"

        if isinstance(data, WBZM3UData.TrackMetadata.TrackArtist):
            return f"#TRACK_ARTIST: {data}\n"

        if isinstance(data, WBZM3UData.TrackMetadata.TrackAlbum):
            return f"#TRACK_ALBUM: {data}\n"

        if isinstance(data, WBZM3UData.TrackMetadata.TrackGenre):
            return f"#TRACK_GENRE: {data}\n"