import os
import unittest
from unittest.mock import Mock, patch

from app.features.memoir.helpers import chapter_to_dict as _chapter_to_dict
from app.features.memoir.memoir_images.storage import CosDownloadUrlError


def _image_stub(**kwargs):
    """构造具有 .placeholder 等属性的 image 对象，供 memoir_image_to_dict 使用。"""
    defaults = {
        "placeholder": "",
        "description": "",
        "order_index": 0,
        "status": "pending",
        "prompt": None,
        "url": None,
        "storage_key": None,
        "provider": None,
        "style": None,
        "size": None,
        "error": None,
        "retryable": None,
        "created_at": None,
        "updated_at": None,
        "section_id": None,
    }
    defaults.update(kwargs)
    return type("ImageStub", (), defaults)()


def _chapter_stub(*, images=None, sections=None):
    """构造带 images/sections 的 chapter stub。images 为 image_stub 列表（section_id=None 的作封面），sections 为 section 列表（含 image_record）。"""
    images = images or []
    sections = sections or []
    return type(
        "ChapterStub",
        (),
        {
            "id": "chapter-1",
            "title": "童年的夏天",
            "content": "",
            "order_index": 0,
            "status": "completed",
            "category": "childhood",
            "images": images,
            "sections": sections,
            "cover_image": None,
            "updated_at": None,
            "is_new": False,
            "source_segments": [],
        },
    )()


class ChaptersRouterImagesTest(unittest.TestCase):
    @patch("app.features.memoir.router.TencentCosStorageService")
    @patch.dict(
        os.environ,
        {
            "TENCENT_COS_BUCKET": "life-echo-dev-1319381411",
            "TENCENT_COS_REGION": "ap-shanghai",
            "TENCENT_COS_BASE_URL": "https://life-echo-dev-1319381411.cos.ap-shanghai.myqcloud.com",
        },
        clear=False,
    )
    def test_chapter_to_dict_returns_signed_image_urls_for_response(self, storage_cls):
        storage = Mock()
        storage.get_download_url.return_value = (
            "https://signed.example.com/memoirs/u1/c1/0-demo.png?sig=123"
        )
        storage_cls.from_settings.return_value = storage

        img0 = _image_stub(
            placeholder="{{IMAGE:南方小镇的青石板路}}",
            description="南方小镇的青石板路",
            status="completed",
            prompt="A serene southern China town",
            url="https://life-echo-dev-1319381411.cos.ap-shanghai.myqcloud.com/memoirs/u1/c1/0-demo.png",
            storage_key="memoirs/u1/c1/0-demo.png",
            section_id=None,
            order_index=0,
        )
        sec = type(
            "SectionStub",
            (),
            {"content": "", "order_index": 0, "image_record": img0, "image_id": None},
        )()
        chapter = _chapter_stub(images=[img0], sections=[sec])

        payload = _chapter_to_dict(chapter)

        self.assertEqual(
            payload["images"][0]["url"],
            "https://signed.example.com/memoirs/u1/c1/0-demo.png?sig=123",
        )
        self.assertEqual(payload["images"][0]["prompt"], "A serene southern China town")
        self.assertNotIn("storage_key", payload["images"][0])

    @patch("app.features.memoir.router.TencentCosStorageService")
    @patch.dict(
        os.environ,
        {
            "TENCENT_COS_BUCKET": "life-echo-dev-1319381411",
            "TENCENT_COS_REGION": "ap-shanghai",
            "TENCENT_COS_BASE_URL": "https://life-echo-dev-1319381411.cos.ap-shanghai.myqcloud.com",
        },
        clear=False,
    )
    def test_chapter_to_dict_preserves_completed_asset_when_signing_fails(
        self, storage_cls
    ):
        storage = Mock()
        storage.get_download_url.side_effect = CosDownloadUrlError(
            "cos unavailable", retryable=True, request_id="req-err"
        )
        storage_cls.from_settings.return_value = storage

        img0 = _image_stub(
            placeholder="{{IMAGE:南方小镇的青石板路}}",
            description="南方小镇的青石板路",
            status="completed",
            prompt="A serene southern China town",
            url="https://life-echo-dev-1319381411.cos.ap-shanghai.myqcloud.com/memoirs/u1/c1/0-demo.png",
            storage_key="memoirs/u1/c1/0-demo.png",
            section_id=None,
            order_index=0,
        )
        sec = type(
            "SectionStub",
            (),
            {"content": "", "order_index": 0, "image_record": img0, "image_id": None},
        )()
        chapter = _chapter_stub(images=[img0], sections=[sec])

        payload = _chapter_to_dict(chapter)

        self.assertEqual(payload["images"][0]["status"], "completed")
        self.assertIsNone(payload["images"][0]["url"])
        self.assertEqual(payload["images"][0]["prompt"], "A serene southern China town")
        self.assertEqual(payload["images"][0]["error"], "image delivery unavailable")
        self.assertNotIn("storage_key", payload["images"][0])

    @patch("app.features.memoir.router.TencentCosStorageService")
    def test_chapter_to_dict_drops_malformed_image_assets(self, storage_cls):
        storage_cls.from_settings.return_value = Mock()
        # 无 sections 时 content/images 来自 _sections_to_content_and_images 得到 []；无有效封面（images 的 section_id 非空）
        img = _image_stub(
            status="completed", placeholder="", description="", section_id="sec1"
        )
        chapter = _chapter_stub(images=[img], sections=[])

        payload = _chapter_to_dict(chapter)

        self.assertEqual(payload["images"], [])

    @patch("app.features.memoir.router.MemoirImageSettings")
    @patch("app.features.memoir.router.TencentCosStorageService")
    def test_chapter_to_dict_hides_non_completed_assets_when_feature_disabled(
        self, storage_cls, memoir_img_settings_cls
    ):
        storage = Mock()
        storage.get_download_url.return_value = (
            "https://signed.example.com/0.png?sig=123"
        )
        storage_cls.from_settings.return_value = storage
        memoir_img_settings_cls.from_settings.return_value = Mock(enabled=False)

        # 仅一个 completed 的 section；enabled=False 时 completed_image_assets 只保留 completed，故仍为 1 条
        img_completed = _image_stub(
            placeholder="{{IMAGE:奶奶坐在院子里的藤椅上}}",
            description="奶奶坐在院子里的藤椅上",
            status="completed",
            url="https://life-echo-dev-1319381411.cos.ap-shanghai.myqcloud.com/memoirs/u1/c1/1-demo.png",
            storage_key="memoirs/u1/c1/1-demo.png",
            order_index=0,
            section_id="s1",
        )
        sec = type(
            "SectionStub",
            (),
            {
                "content": "",
                "order_index": 0,
                "image_record": img_completed,
                "image_id": None,
            },
        )()
        chapter = _chapter_stub(images=[img_completed], sections=[sec])

        payload = _chapter_to_dict(chapter)

        self.assertEqual(len(payload["images"]), 1)
        self.assertEqual(payload["images"][0]["status"], "completed")

    @patch("app.features.memoir.router.TencentCosStorageService")
    @patch.dict(os.environ, {"MEMOIR_IMAGE_ENABLED": "true"}, clear=False)
    def test_chapter_to_dict_preserves_retryable_flag_for_failed_assets(
        self, storage_cls
    ):
        storage_cls.from_settings.return_value = Mock()

        img = _image_stub(
            placeholder="{{IMAGE:南方小镇的青石板路}}",
            description="南方小镇的青石板路",
            status="failed",
            url=None,
            error="upload denied",
            retryable=False,
            order_index=0,
        )
        sec = type(
            "SectionStub",
            (),
            {"content": "", "order_index": 0, "image_record": img, "image_id": None},
        )()
        chapter = _chapter_stub(images=[img], sections=[sec])

        payload = _chapter_to_dict(chapter)

        self.assertEqual(payload["images"][0]["status"], "failed")
        self.assertFalse(payload["images"][0]["retryable"])