"""Summarizer 标题树接入的单元测试"""

from app.core.summarizer import Summarizer
from app.models.document import SummaryLevel


class FakeOllama:
    """记录调用次数的 OllamaClient 替身"""

    def __init__(self) -> None:
        self.prompts: list[str] = []

    async def generate(self, prompt: str) -> str:
        self.prompts.append(prompt)
        return "LLM 生成结果"


def _structured_text() -> str:
    """构造带标题结构且长度 ≥ 500 的文档（不触发 2.5 回退）"""
    paragraph = "这是章节正文内容，包含足够多的信息量。" * 10
    return f"# 安装指南\n{paragraph}\n## 环境准备\n{paragraph}\n## 安装步骤\n{paragraph}"


class TestStructuredDocument:
    """结构化文档：L2 直接使用标题树，不调 LLM"""

    async def test_l2_from_headings_skips_llm(self):
        ollama = FakeOllama()
        summarizer = Summarizer(ollama=ollama)  # type: ignore[arg-type]

        summary = await summarizer.summarize(_structured_text(), title="安装文档")

        assert summary.level == SummaryLevel.L3
        # L1 + L3 两次调用，跳过了 L2 的 LLM 调用
        assert len(ollama.prompts) == 2
        # 大纲由标题树渲染，包含标题文本与层级缩进
        assert summary.l2_outline is not None
        assert "- 安装指南" in summary.l2_outline
        assert "  - 环境准备" in summary.l2_outline
        assert "  - 安装步骤" in summary.l2_outline
        assert summary.l2_outline != "LLM 生成结果"
        # L3 的 prompt 中注入了标题树大纲
        assert "安装指南" in ollama.prompts[1]


class TestPlainDocument:
    """无结构文档：L2 回退 LLM 生成"""

    async def test_l2_falls_back_to_llm(self):
        ollama = FakeOllama()
        summarizer = Summarizer(ollama=ollama)  # type: ignore[arg-type]
        text = "这是一段没有标题结构的正文内容，" * 40  # 640 字符，不触发 2.5 回退

        summary = await summarizer.summarize(text, title="")

        assert summary.level == SummaryLevel.L3
        # L1 + L2 + L3 三次调用
        assert len(ollama.prompts) == 3
        assert summary.l2_outline == "LLM 生成结果"


class TestFallbackUnaffected:
    """2.5 级回退逻辑不受标题树改造影响"""

    async def test_short_structured_text_still_fallback(self):
        ollama = FakeOllama()
        summarizer = Summarizer(ollama=ollama)  # type: ignore[arg-type]
        text = "# 标题一\n简短内容。\n# 标题二\n简短内容。"

        summary = await summarizer.summarize(text, title="")

        assert summary.level == SummaryLevel.L2_HALF
        assert summary.l2_outline is None
        # L1 + L2.5 两次调用
        assert len(ollama.prompts) == 2