"""章节封面：无 cover_asset_id 时用正文首张 asset:// 作列表封面。"""

from unittest.mock import MagicMock

from app.features.memoir.helpers import chapter_cover_to_dict


def test_cover_falls_back_to_first_inline_asset_url() -> None:
    ch = MagicMock(spec=[])
    ch.canonical_markdown = "正文\n\n![场景](asset://img-1)"
    ch.cover_asset_id = None
    ch.story_links = []
    ch.images = []
    m = chapter_cover_to_dict(
        ch,
        asset_url_map={"img-1": "https://cos.example.com/signed-1"},
        markdown_for_response=None,
    )
    assert m is not None
    assert m["url"] == "https://cos.example.com/signed-1"
    assert m["status"] == "completed"


def test_cover_from_reading_segments_when_canonical_has_no_asset() -> None:
    """分段快照里有 asset://，章节 canonical 未带图时仍能出封面 URL。"""
    ch = MagicMock(spec=[])
    ch.canonical_markdown = "只有文字没有图" * 20
    ch.cover_asset_id = None
    ch.story_links = []
    ch.images = []
    ch.reading_segments_json = [
        {"story_id": "s1", "body_markdown": "![景](asset://seg-1)"}
    ]
    m = chapter_cover_to_dict(
        ch,
        asset_url_map={"seg-1": "https://cos.example.com/seg"},
        markdown_for_response=None,
    )
    assert m is not None
    assert m["url"] == "https://cos.example.com/seg"


def test_cover_prefers_cover_asset_id_over_inline() -> None:
    ch = MagicMock(spec=[])
    ch.canonical_markdown = "![a](asset://inline-1)"
    ch.cover_asset_id = "cover-99"
    ch.story_links = []
    ch.images = []
    m = chapter_cover_to_dict(
        ch,
        asset_url_map={
            "inline-1": "https://cos.example.com/inline",
            "cover-99": "https://cos.example.com/cover",
        },
        markdown_for_response=None,
    )
    assert m["url"] == "https://cos.example.com/cover"