"""StoryRouteAgent：LLM JSON 决策与非法 target 回退。"""

import unittest
from types import SimpleNamespace
from unittest.mock import Mock

from app.agents.memoir.story_route_agent import StoryRouteAgent


def _story_stub(sid: str, title: str = "T"):
    return SimpleNamespace(
        id=sid,
        title=title,
        canonical_markdown="预览正文",
        chapter_links=[],
    )


class StoryRouteAgentTest(unittest.TestCase):
    def test_no_llm_returns_new_story(self):
        agent = StoryRouteAgent()
        out = agent.decide(
            chapter_category="childhood",
            chapter_title="童年",
            batch_transcript="hello",
            candidate_stories=[_story_stub("s1")],
            llm=None,
            valid_story_ids={"s1"},
        )
        self.assertEqual(out.decision, "new_story")
        self.assertIsNone(out.new_story_title)

    def test_append_invalid_id_falls_back_to_new_story(self):
        agent = StoryRouteAgent()
        llm = Mock()
        bound = Mock()
        llm.bind.return_value = bound
        bound.invoke.return_value = SimpleNamespace(
            content='{"decision":"append_story","target_story_id":"unknown"}'
        )
        out = agent.decide(
            chapter_category="childhood",
            chapter_title="童年",
            batch_transcript="hello",
            candidate_stories=[_story_stub("s1")],
            llm=llm,
            valid_story_ids={"s1"},
        )
        self.assertEqual(out.decision, "new_story")
        self.assertEqual(out.reason, "invalid_target")

    def test_append_valid_target(self):
        agent = StoryRouteAgent()
        llm = Mock()
        bound = Mock()
        llm.bind.return_value = bound
        bound.invoke.return_value = SimpleNamespace(
            content='{"decision":"append_story","target_story_id":"s1"}'
        )
        out = agent.decide(
            chapter_category="childhood",
            chapter_title="童年",
            batch_transcript="more text",
            candidate_stories=[_story_stub("s1")],
            llm=llm,
            valid_story_ids={"s1"},
        )
        self.assertEqual(out.decision, "append_story")
        self.assertEqual(out.target_story_id, "s1")


if __name__ == "__main__":
    unittest.main()