import pytest
from types import SimpleNamespace

from genesis.writer.writer_agent import (
    WriterAgent,
    WRITER_PROMPT_TEMPLATE,
    CHAPTER_OUTPUT_SCHEMA,
)
from genesis.writer.models import GenerationContext, ChapterSpec
from genesis.writer.writer_state import WriterState
from genesis.writer.exceptions import WriterGenerationError


class FakeEngine:
    def __init__(self):
        self.calls = 0

    def chat_structured(self, *, session_id, prompt, variables, schema, retry_count=2):
        self.calls += 1
        return SimpleNamespace(
            data={"title": variables["title"], "blocks": [{"type": "paragraph", "text": "ok"}]},
            status="ok",
        )


class FakePromptRegistry:
    @staticmethod
    def get_or_create(name, template):
        return SimpleNamespace(name=name, version="1", template=template)


def _ctx(cid, title):
    return GenerationContext(
        chapter_id=cid,
        title=title,
        template_marker=ChapterSpec(chapter_id=cid, title=title, section_placeholder=None),
        structured_source="source text",
        write_rules=["W1"],
        design_rules=["D1"],
        template_styles={"Heading1"},
        prior_state=None,
    )


def test_generate_chapter_success():
    agent = WriterAgent(
        session_id="s",
        engine=FakeEngine(),
        prompt_registry=FakePromptRegistry(),
        state=WriterState(["db_design"]),
    )
    content = agent.generate_chapter(_ctx("db_design", "DB 設計"))
    assert content.chapter_id == "db_design"
    assert content.blocks and content.blocks[0].type == "paragraph"


def test_prompt_template_enforces_title_language():
    # 语言约束：正文需与章节标题语言一致（模板为日文时输出日文）
    assert "语言约束" in WRITER_PROMPT_TEMPLATE
    assert "{{title}}" in WRITER_PROMPT_TEMPLATE


def test_generate_chapter_retries():
    class Boom(FakeEngine):
        def chat_structured(self, *, session_id, prompt, variables, schema, retry_count=2):
            raise RuntimeError("boom")

    agent = WriterAgent(
        session_id="s",
        engine=Boom(),
        prompt_registry=FakePromptRegistry(),
        state=WriterState(["db_design"]),
        max_retries=2,
    )
    with pytest.raises(WriterGenerationError):
        agent.generate_chapter(_ctx("db_design", "DB 設計"))


class AsyncFakeEngine:
    async def chat_structured(self, *, session_id, prompt, variables, schema, retry_count=2):
        return SimpleNamespace(
            data={"title": variables["title"], "blocks": [{"type": "paragraph", "text": "ok"}]},
            status="ok",
        )


def test_generate_chapter_with_async_engine():
    agent = WriterAgent(
        session_id="s",
        engine=AsyncFakeEngine(),
        prompt_registry=FakePromptRegistry(),
        state=WriterState(["db_design"]),
    )
    content = agent.generate_chapter(_ctx("db_design", "DB 設計"))
    assert content.chapter_id == "db_design"
    assert content.blocks and content.blocks[0].type == "paragraph"


def test_generate_chapter_propagates_engine_error_detail():
    class FailingEngine:
        def chat_structured(self, *, session_id, prompt, variables, schema, retry_count=2):
            return SimpleNamespace(
                data={},
                status="failed",
                error="LLM HTTP 401: invalid key",
                error_code="LLM_NETWORK_ERROR",
            )

    agent = WriterAgent(
        session_id="s",
        engine=FailingEngine(),
        prompt_registry=FakePromptRegistry(),
        state=WriterState(["db_design"]),
        max_retries=1,
    )
    with pytest.raises(WriterGenerationError) as exc:
        agent.generate_chapter(_ctx("db_design", "DB 設計"))
    assert "LLM HTTP 401" in str(exc.value)
    assert "LLM_NETWORK_ERROR" in str(exc.value)