"""download_backends — the single predicate that routes a platform to the
native ingester vs. gallery-dl. Pure, no DB."""

from pathlib import Path

import pytest

from backend.app.services.download_backends import (
    NATIVE_INGESTER_PLATFORMS,
    _campaign_resolution_error,
    _native_ingester_cls,
    _unsupported_platform_message,
    run_download,
    uses_native_ingester,
    verify_source_credential,
)
from backend.app.services.gallery_dl import ErrorType
from backend.app.services.pixiv_ingester import PixivIngester


def test_native_platforms():
    for platform in ("patreon", "subscribestar"):
        assert uses_native_ingester(platform) is True
        assert platform in NATIVE_INGESTER_PLATFORMS


def test_pixiv_is_no_longer_native():
    """Retired at milestone #406. The refusal below is what stops it falling
    through to gallery-dl now that it is not native."""
    assert uses_native_ingester("pixiv") is False
    assert "pixiv" not in NATIVE_INGESTER_PLATFORMS


# --- the retired-platform guard (#406 phase 1) -----------------------------


class _RecordingGalleryDL:
    """Stands in for GalleryDLService: records whether a download was attempted."""

    def __init__(self):
        self.calls = []

    async def download(self, **kwargs):
        self.calls.append(kwargs["platform"])
        return "reached gallery-dl"


def _ctx(platform):
    return {
        "platform": platform, "url": f"https://example.invalid/{platform}",
        "artist_slug": "someone", "cookies_path": None, "auth_token": None,
    }


@pytest.mark.asyncio
async def test_a_retired_platform_never_reaches_a_downloader():
    """An enabled source on a retired platform is data that survives a deploy.
    Unguarded, pixiv — no longer native — would fall straight through to the
    gallery-dl branch, which still has a pixiv extractor."""
    gdl = _RecordingGalleryDL()
    result, campaign_id = await run_download(
        ctx=_ctx("pixiv"), source_config=None, skip_value=False, mode=None,
        gdl=gdl, sync_session_factory=None,
    )
    assert gdl.calls == []
    assert result.success is False
    assert result.error_type == ErrorType.UNSUPPORTED_URL
    assert "pixiv" in result.error_message
    assert campaign_id is None


@pytest.mark.asyncio
async def test_a_supported_gallery_dl_platform_still_reaches_gallery_dl():
    """The positive control. Without it, a guard that refused EVERY platform
    would pass the test above just as well (rule #167)."""
    gdl = _RecordingGalleryDL()
    result, _ = await run_download(
        ctx=_ctx("hentaifoundry"), source_config=None, skip_value=False, mode=None,
        gdl=gdl, sync_session_factory=None,
    )
    assert gdl.calls == ["hentaifoundry"]
    assert result == "reached gallery-dl"


def test_the_guard_discriminates_by_registration():
    assert _unsupported_platform_message("hentaifoundry") is None
    assert _unsupported_platform_message("patreon") is None
    assert _unsupported_platform_message("pixiv") is not None
    assert _unsupported_platform_message("deviantart") is not None


@pytest.mark.asyncio
async def test_verifying_a_retired_platform_is_inconclusive_not_rejected():
    """Nothing is probed, so nothing is rejected — returning False would tell the
    operator their credential is bad when the platform is simply gone."""
    ok, message = await verify_source_credential(
        platform="pixiv", url="https://www.pixiv.net/users/1", artist_slug="someone",
        config_overrides=None, cookies_path=None, auth_token=None,
        images_root=Path("/nonexistent"),
    )
    assert ok is None
    assert "pixiv" in message


def test_gallery_dl_platforms_are_not_native():
    # The platforms still served by gallery-dl must NOT route to the native
    # ingester — guards an accidental over-broad migration.
    for platform in ("hentaifoundry", "discord"):
        assert uses_native_ingester(platform) is False


def test_unknown_platform_is_not_native():
    assert uses_native_ingester("nonsense") is False


def test_pixiv_dispatches_to_its_ingester():
    assert _native_ingester_cls("pixiv") is PixivIngester


def test_pixiv_resolution_error_names_the_expected_url_shape():
    msg = _campaign_resolution_error("pixiv", "https://www.pixiv.net/artworks/1")
    assert "pixiv user id" in msg
    assert "users/<id>" in msg