from __future__ import annotations

from pathlib import Path

import pytest

from yt_shorts_downloader import api
from yt_shorts_downloader.exceptions import InvalidSessionError, InvalidUrlError
from yt_shorts_downloader.models import DownloadedVideo, SessionValidation


def _build_valid_session_validation(path: Path) -> SessionValidation:
    return SessionValidation(True, True, True, True, str(path))


def test_download_returns_binary_mp4(monkeypatch: pytest.MonkeyPatch, tmp_path: Path) -> None:
    expected_content = b"mp4-binary-content"

    def fake_validate_session_file(path: Path) -> SessionValidation:
        return _build_valid_session_validation(path)

    def fake_download_video(*, url: str, output_dir: Path, session_path: Path) -> Path:
        del url, session_path
        downloaded_file = output_dir / "video.mp4"
        downloaded_file.write_bytes(expected_content)
        return downloaded_file

    monkeypatch.setattr(api, "validate_session_file", fake_validate_session_file)
    monkeypatch.setattr(api, "download_video", fake_download_video)

    downloaded_video = api.download(
        "https://youtube.com/shorts/example",
        session_path="cookies.txt",
    )

    assert downloaded_video == DownloadedVideo(
        filename="video.mp4",
        content=expected_content,
    )


def test_download_to_path_returns_path_from_downloader(
    monkeypatch: pytest.MonkeyPatch, tmp_path: Path
) -> None:
    expected_path = tmp_path / "video.mp4"

    def fake_validate_session_file(path: Path) -> SessionValidation:
        return _build_valid_session_validation(path)

    def fake_download_video(*, url: str, output_dir: Path, session_path: Path) -> Path:
        del url, session_path
        expected_path.write_bytes(b"mp4")
        return output_dir / expected_path.name

    monkeypatch.setattr(api, "validate_session_file", fake_validate_session_file)
    monkeypatch.setattr(api, "download_video", fake_download_video)

    downloaded_path = api.download_to_path(
        "https://youtube.com/shorts/example",
        session_path="cookies.txt",
        output_dir=tmp_path,
    )

    assert downloaded_path == expected_path


def test_download_rejects_invalid_url() -> None:
    with pytest.raises(InvalidUrlError):
        api.download("https://example.com/watch?v=1", session_path="cookies.txt")


def test_download_rejects_invalid_session(monkeypatch: pytest.MonkeyPatch) -> None:
    def fake_validate_session_file(path: Path) -> SessionValidation:
        del path
        return SessionValidation(False, False, False, False, "bad session")

    monkeypatch.setattr(api, "validate_session_file", fake_validate_session_file)

    with pytest.raises(InvalidSessionError, match="bad session"):
        api.download("https://youtube.com/shorts/example", session_path="cookies.txt")