import os

import streamlit as st
import uuid
from typing import Sequence

from app.adapters.aws.s3 import S3Client
from app.adapters.db.base import DB
from app.assets.models import GlobalParticipant, Asset, AssetMetaData
from app.assets.repositories import AssetRepository, GlobalParticipantRepository
from app.config import Settings
from anydi import singleton

import requests


@singleton
class AssetService:
    def __init__(
        self,
        db: DB,
        asset_repository: AssetRepository,
        global_participant_repository: GlobalParticipantRepository,
        s3_client: S3Client,
        settings: Settings,
    ) -> None:
        self.s3_client = s3_client
        self.db = db
        self.asset_repository = asset_repository
        self.global_participant_repository = global_participant_repository
        self.settings = settings

    def download_video(self, url: str, name: str, target_directory: str) -> str:
        local_filename = f"{name}.mp4"
        local_filepath = os.path.join(target_directory, local_filename)

        try:
            with requests.get(url, stream=True) as r:
                r.raise_for_status()
                with open(local_filepath, "wb") as f:
                    for chunk in r.iter_content(chunk_size=8192):
                        f.write(chunk)
        except requests.exceptions.RequestException as e:
            raise RuntimeError(f"Failed to download video from URL: {url}. Error: {e}")

        if not os.path.exists(local_filepath):
            raise FileNotFoundError(
                f"Downloaded file not found at expected path: {local_filepath}"
            )

        return local_filepath

    def find_all_global_participants(self) -> Sequence[GlobalParticipant]:
        return self.global_participant_repository.all()

    def add_song(
        self,
        song_name: str,
        key: str,
        artist: GlobalParticipant | None = None,
        artist_name: str | None = None,
    ) -> Asset:
        global_participant: GlobalParticipant | None = None

        if artist:
            global_participant = self.asset_repository.db.session.merge(artist)
        elif artist_name:
            gp_id = str(uuid.uuid4())
            global_participant = GlobalParticipant(id=gp_id, name=artist_name)
        else:
            raise ValueError()

        new_asset_id = str(uuid.uuid4())

        asset = Asset(
            id=new_asset_id,
            external_id=str(uuid.uuid4()),
            type="YOUTUBE_URL",
            s3_key=key,
            global_participant=global_participant,
            asset_meta_data=AssetMetaData(
                asset_id=new_asset_id,
                asset_name=song_name,
            ),
        )

        self.asset_repository.add(asset)
        self.asset_repository.db.session.commit()

        st.session_state.asset = asset

        return asset