from typing import Union
from discord.ext.commands import Context
from discord import Client
from Handlers.AbstractHandler import AbstractHandler
from Handlers.HandlerResponse import HandlerResponse
from Config.Exceptions import BadCommandUsage, VulkanError, ErrorRemoving, InvalidInput, NumberRequired


class RemoveHandler(AbstractHandler):
    def __init__(self, ctx: Context, bot: Client) -> None:
        super().__init__(ctx, bot)

    async def run(self, position: str) -> HandlerResponse:
        if not self.player.playlist:
            embed = self.embeds.NOT_PLAYING()
            error = BadCommandUsage()
            return HandlerResponse(self.ctx, embed, error)

        error = self.__validate_input(position)
        if error:
            embed = self.embeds.ERROR_EMBED(error.message)
            return HandlerResponse(self.ctx, embed, error)

        position = self.__sanitize_input(position)
        if not self.player.playlist.validate_position(position):
            error = InvalidInput()
            embed = self.embeds.PLAYLIST_RANGE_ERROR()
            return HandlerResponse(self.ctx, embed, error)

        try:
            song = self.player.playlist.remove_song(position)
            name = song.title if song.title else song.identifier

            embed = self.embeds.SONG_REMOVED(name)
            return HandlerResponse(self.ctx, embed)
        except:
            error = ErrorRemoving()
            embed = self.embeds.ERROR_REMOVING()
            return HandlerResponse(self.ctx, embed, error)

    def __validate_input(self, position: str) -> Union[VulkanError, None]:
        try:
            position = int(position)
        except:
            return NumberRequired(self.messages.ERROR_NUMBER)

    def __sanitize_input(self, position: str) -> int:
        position = int(position)

        if position == -1:
            position = len(self.player.playlist)
        return position