"""UnifiedRenderService 单元测试.

测试图层分组算法、filter_complex 构建、以及渲染流程。
"""

from __future__ import annotations

from dataclasses import dataclass, field
from pathlib import Path
from typing import Any
from unittest.mock import MagicMock, patch

import pytest
from video_processing.unified_render_service import (
    RenderLayer,
    RenderResult,
    ResolvedClip,
    UnifiedRenderService,
    _resolve_layer_role,
)

# ── Fixtures ──────────────────────────────────────────────────────────────────


@dataclass
class FakeClip:
    """模拟 EditPlanClip。"""

    id: str
    plan_id: str = "plan_001"
    clip_type: str = "main"
    order: int = 0
    asset_id: str = ""
    text_content: str = ""
    start_time: float = 0.0
    duration: float = 0.0
    transition_effect: str = "cut"
    status: str = "ready"
    config: dict[str, Any] = field(default_factory=dict)


@dataclass
class FakePlan:
    """模拟 EditPlan。"""

    id: str = "plan_001"
    name: str = "测试计划"


def _make_clip(
    clip_id: str,
    clip_type: str = "main",
    order: int = 0,
    asset_id: str = "",
    duration: float = 0.0,
    transition_effect: str = "cut",
    config: dict[str, Any] | None = None,
) -> FakeClip:
    return FakeClip(
        id=clip_id,
        clip_type=clip_type,
        order=order,
        asset_id=asset_id or f"asset_{clip_id}.mp4",
        duration=duration,
        transition_effect=transition_effect,
        config=config or {},
    )


def _make_service(
    clips: list[FakeClip] | None = None,
    asset_paths: dict[str, Path] | None = None,
    work_dir: Path | None = None,
) -> UnifiedRenderService:
    """创建测试用的 UnifiedRenderService 实例。

    如果未提供 asset_paths，自动从 clips 生成默认映射
    （asset_id → /tmp/asset_{clip_id}.mp4）。
    """
    plan = FakePlan()
    clips = clips or []
    work_dir = work_dir or Path("/tmp/test_render")
    if asset_paths is None:
        asset_paths = {}
        for c in clips:
            if c.asset_id:
                asset_paths[c.asset_id] = Path(f"/tmp/{c.asset_id}")
    return UnifiedRenderService(
        plan=plan,
        clips=clips,
        asset_path_map=asset_paths,
        work_dir=work_dir,
    )


def _patch_path_exists():
    """Patch Path.exists() 让测试路径返回 True。"""
    return patch("pathlib.Path.exists", return_value=True)


# ── 测试 _resolve_layer_role ─────────────────────────────────────────────────


class TestResolveLayerRole:
    """测试 clip_type → layer role 映射。"""

    def test_main_default(self):
        assert _resolve_layer_role("main", {}) == "main"

    def test_main_with_b_roll_role(self):
        assert _resolve_layer_role("main", {"role": "b_roll"}) == "broll"

    def test_overlay(self):
        assert _resolve_layer_role("overlay", {}) == "overlay"

    def test_background(self):
        assert _resolve_layer_role("background", {}) == "background"

    def test_corner_voice(self):
        assert _resolve_layer_role("corner_voice", {}) == "corner_voice"

    def test_b_roll(self):
        assert _resolve_layer_role("b_roll", {}) == "broll"

    def test_intro(self):
        assert _resolve_layer_role("intro", {}) == "main"

    def test_outro(self):
        assert _resolve_layer_role("outro", {}) == "main"


# ── 测试图层分组 ──────────────────────────────────────────────────────────────


class TestGroupClipsIntoLayers:
    """测试 _group_clips_into_layers 方法。"""

    def test_group_clips_one_take(self):
        """4 个 main clips → 1 个 main_layer。"""
        clips = [
            _make_clip("c1", "main", order=0),
            _make_clip("c2", "main", order=1),
            _make_clip("c3", "main", order=2),
            _make_clip("c4", "main", order=3),
        ]
        svc = _make_service(clips)
        with _patch_path_exists(), patch("video_processing.unified_render_service.probe_duration", return_value=5.0):
            resolved = svc._resolve_clips()
            layers = svc._group_clips_into_layers(resolved)

        assert len(layers) == 1
        assert layers[0].role == "main"
        assert len(layers[0].clips) == 4
        assert layers[0].z_index == 0

    def test_group_clips_pip(self):
        """1 main + 2 overlay → main_layer + overlay_layer。"""
        clips = [
            _make_clip("c1", "main", order=0),
            _make_clip("c2", "overlay", order=1),
            _make_clip("c3", "overlay", order=2),
        ]
        svc = _make_service(clips)
        with _patch_path_exists(), patch("video_processing.unified_render_service.probe_duration", return_value=5.0):
            resolved = svc._resolve_clips()
            layers = svc._group_clips_into_layers(resolved)

        roles = {lyr.role for lyr in layers}
        assert "main" in roles
        assert "overlay" in roles

        main_layer = next(lyr for lyr in layers if lyr.role == "main")
        overlay_layer = next(lyr for lyr in layers if lyr.role == "overlay")
        assert len(main_layer.clips) == 1
        assert len(overlay_layer.clips) == 2
        assert overlay_layer.z_index > main_layer.z_index

    def test_group_clips_voice_over(self):
        """3 个 main(b_roll) clips → 1 个 broll_layer。"""
        clips = [
            _make_clip("c1", "main", order=0, config={"role": "b_roll"}),
            _make_clip("c2", "main", order=1, config={"role": "b_roll"}),
            _make_clip("c3", "main", order=2, config={"role": "b_roll"}),
        ]
        svc = _make_service(clips)
        with _patch_path_exists(), patch("video_processing.unified_render_service.probe_duration", return_value=5.0):
            resolved = svc._resolve_clips()
            layers = svc._group_clips_into_layers(resolved)

        assert len(layers) == 1
        assert layers[0].role == "broll"
        assert len(layers[0].clips) == 3

    def test_group_clips_voice_pip(self):
        """1 background + 1 corner_voice + 2 b_roll → 3 layers。"""
        clips = [
            _make_clip("c1", "background", order=0),
            _make_clip("c2", "corner_voice", order=1),
            _make_clip("c3", "b_roll", order=2),
            _make_clip("c4", "b_roll", order=3),
        ]
        svc = _make_service(clips)
        with _patch_path_exists(), patch("video_processing.unified_render_service.probe_duration", return_value=5.0):
            resolved = svc._resolve_clips()
            layers = svc._group_clips_into_layers(resolved)

        roles = {lyr.role for lyr in layers}
        assert roles == {"background", "corner_voice", "broll"}
        assert len(layers) == 3

        # z_index 排序
        assert layers[0].z_index <= layers[1].z_index <= layers[2].z_index

    def test_group_clips_intro_outro(self):
        """intro + 2 main + outro → 1 main_layer（4 clips，按 order 排序）。"""
        clips = [
            _make_clip("intro", "intro", order=0),
            _make_clip("c1", "main", order=1),
            _make_clip("c2", "main", order=2),
            _make_clip("outro", "outro", order=3),
        ]
        svc = _make_service(clips)
        with _patch_path_exists(), patch("video_processing.unified_render_service.probe_duration", return_value=5.0):
            resolved = svc._resolve_clips()
            layers = svc._group_clips_into_layers(resolved)

        assert len(layers) == 1
        assert layers[0].role == "main"
        assert len(layers[0].clips) == 4
        # 按 order 排序
        orders = [c.order for c in layers[0].clips]
        assert orders == [0, 1, 2, 3]


# ── 测试 _resolve_clips ──────────────────────────────────────────────────────


class TestResolveClips:
    """测试 _resolve_clips 方法。"""

    def test_skip_missing_asset(self):
        """跳过 asset_id 在 asset_path_map 中找不到的 clip。"""
        clips = [
            _make_clip("c1", "main", order=0, asset_id="asset_1.mp4"),
            _make_clip("c2", "main", order=1, asset_id="missing.mp4"),
        ]
        # 只有 asset_1.mp4 存在
        asset_paths = {"asset_1.mp4": Path("/tmp/asset_1.mp4")}

        svc = _make_service(clips, asset_paths)

        with _patch_path_exists(), patch("video_processing.unified_render_service.probe_duration", return_value=5.0):
            resolved = svc._resolve_clips()

        assert len(resolved) == 1
        assert resolved[0].clip_id == "c1"

    def test_skip_empty_asset_id(self):
        """跳过 asset_id 为空的 clip。"""
        clips = [
            _make_clip("c1", "main", order=0, asset_id=""),
            _make_clip("c2", "main", order=1, asset_id="asset_2.mp4"),
        ]
        asset_paths = {"asset_2.mp4": Path("/tmp/asset_2.mp4")}

        svc = _make_service(clips, asset_paths)

        with _patch_path_exists(), patch("video_processing.unified_render_service.probe_duration", return_value=5.0):
            resolved = svc._resolve_clips()

        assert len(resolved) == 1
        assert resolved[0].clip_id == "c2"

    def test_sort_by_order(self):
        """解析后的 clips 按 order 排序。"""
        clips = [
            _make_clip("c3", "main", order=3, asset_id="a3.mp4"),
            _make_clip("c1", "main", order=1, asset_id="a1.mp4"),
            _make_clip("c2", "main", order=2, asset_id="a2.mp4"),
        ]
        asset_paths = {
            "a1.mp4": Path("/tmp/a1.mp4"),
            "a2.mp4": Path("/tmp/a2.mp4"),
            "a3.mp4": Path("/tmp/a3.mp4"),
        }

        svc = _make_service(clips, asset_paths)

        with _patch_path_exists(), patch("video_processing.unified_render_service.probe_duration", return_value=5.0):
            resolved = svc._resolve_clips()

        orders = [c.order for c in resolved]
        assert orders == [1, 2, 3]


# ── 测试 _build_filter_complex ───────────────────────────────────────────────


class TestBuildFilterComplex:
    """测试 _build_filter_complex 方法。"""

    def test_single_layer_single_clip(self):
        """只有 1 个 main clip → 简单 scale + setpts。"""
        clips = [_make_clip("c1", "main", order=0)]
        asset_paths = {"asset_c1.mp4": Path("/tmp/asset_c1.mp4")}
        svc = _make_service(clips, asset_paths)

        with _patch_path_exists(), patch("video_processing.unified_render_service.probe_duration", return_value=5.0):
            resolved = svc._resolve_clips()
            layers = svc._group_clips_into_layers(resolved)
            fc, input_args = svc._build_filter_complex(layers)

        assert "-i" in input_args
        assert "/tmp/asset_c1.mp4" in input_args
        assert "scale=" in fc
        assert "[final_video]" in fc

    def test_single_layer_multi_clips(self):
        """多个 main clips → xfade 串联。"""
        clips = [
            _make_clip("c1", "main", order=0, duration=3.0),
            _make_clip("c2", "main", order=1, duration=3.0),
        ]
        asset_paths = {
            "asset_c1.mp4": Path("/tmp/asset_c1.mp4"),
            "asset_c2.mp4": Path("/tmp/asset_c2.mp4"),
        }
        svc = _make_service(clips, asset_paths)

        with _patch_path_exists(), patch("video_processing.unified_render_service.probe_duration", return_value=5.0):
            resolved = svc._resolve_clips()
            layers = svc._group_clips_into_layers(resolved)
            fc, input_args = svc._build_filter_complex(layers)

        assert input_args.count("-i") == 2
        assert "xfade=" in fc
        assert "[final_video]" in fc

    def test_with_overlay(self):
        """main + overlay → overlay 滤镜。"""
        clips = [
            _make_clip("c1", "main", order=0),
            _make_clip("c2", "overlay", order=1),
        ]
        asset_paths = {
            "asset_c1.mp4": Path("/tmp/asset_c1.mp4"),
            "asset_c2.mp4": Path("/tmp/asset_c2.mp4"),
        }
        svc = _make_service(clips, asset_paths)

        with _patch_path_exists(), patch("video_processing.unified_render_service.probe_duration", return_value=5.0):
            resolved = svc._resolve_clips()
            layers = svc._group_clips_into_layers(resolved)
            fc, input_args = svc._build_filter_complex(layers)

        assert "overlay=" in fc
        assert "[final_video]" in fc

    def test_setpts_before_fps_in_xfade_inputs(self):
        """多视频 xfade 模式：setpts=PTS-STARTPTS 必须在 fps 之前，确保 xfade 时各片段 PTS 一致。

        构造两个不同时长的视频片段，验证生成的 filter_complex 中每个片段的
        预处理滤镜链里 setpts 都在 fps 前面。
        """
        clips = [
            _make_clip("c1", "main", order=0, duration=3.0),
            _make_clip("c2", "main", order=1, duration=5.0),
        ]
        asset_paths = {
            "asset_c1.mp4": Path("/tmp/asset_c1.mp4"),
            "asset_c2.mp4": Path("/tmp/asset_c2.mp4"),
        }
        svc = _make_service(clips, asset_paths)

        with _patch_path_exists(), patch("video_processing.unified_render_service.probe_duration", return_value=5.0):
            resolved = svc._resolve_clips()
            layers = svc._group_clips_into_layers(resolved)
            fc, _ = svc._build_filter_complex(layers)

        # 确保 xfade 存在
        assert "xfade=" in fc

        # 提取每个 clip 的预处理滤镜链（[i:v]...[vi] 部分）
        # 验证：每个 clip 滤镜链中，setpts=PTS-STARTPTS 的最后一次出现
        # 必须在 fps= 的前面（PTS 归一化后再统一帧率）
        import re

        clip_pattern = re.compile(r"\[(\d+):v\](.+?)\[v\d+\]")
        matches = clip_pattern.findall(fc)
        assert len(matches) == 2, f"Expected 2 clip preprocessing chains, got {len(matches)}"

        for idx, chain_str in matches:
            # 找到所有 setpts 和 fps 的位置
            setpts_positions = [m.start() for m in re.finditer(r"setpts=PTS-STARTPTS", chain_str)]
            fps_positions = [m.start() for m in re.finditer(r"fps=\d+", chain_str)]

            assert setpts_positions, f"clip {idx}: 未找到 setpts=PTS-STARTPTS"
            assert fps_positions, f"clip {idx}: 未找到 fps="

            # 最后一个 setpts 必须在第一个 fps 之前
            last_setpts = max(setpts_positions)
            first_fps = min(fps_positions)
            assert last_setpts < first_fps, (
                f"clip {idx}: setpts(position={last_setpts}) 应该在 fps(position={first_fps}) 之前。"
                f"滤镜链: {chain_str}"
            )

    def test_setpts_before_fps_single_clip(self):
        """单视频模式（一镜到底）：setpts 也必须在 fps 之前。

        单视频虽然没有 xfade，但滤镜链顺序应保持一致，确保 PTS 处理逻辑统一。
        """
        clips = [_make_clip("c1", "main", order=0, duration=5.0)]
        asset_paths = {"asset_c1.mp4": Path("/tmp/asset_c1.mp4")}
        svc = _make_service(clips, asset_paths)

        with _patch_path_exists(), patch("video_processing.unified_render_service.probe_duration", return_value=5.0):
            resolved = svc._resolve_clips()
            layers = svc._group_clips_into_layers(resolved)
            fc, _ = svc._build_filter_complex(layers)

        import re

        clip_pattern = re.compile(r"\[(\d+):v\](.+?)\[v\d+\]")
        matches = clip_pattern.findall(fc)
        assert len(matches) == 1

        chain_str = matches[0][1]
        setpts_positions = [m.start() for m in re.finditer(r"setpts=PTS-STARTPTS", chain_str)]
        fps_positions = [m.start() for m in re.finditer(r"fps=\d+", chain_str)]

        assert setpts_positions, "单视频: 未找到 setpts=PTS-STARTPTS"
        assert fps_positions, "单视频: 未找到 fps="

        last_setpts = max(setpts_positions)
        first_fps = min(fps_positions)
        assert last_setpts < first_fps, (
            f"单视频: setpts(position={last_setpts}) 应该在 fps(position={first_fps}) 之前。" f"滤镜链: {chain_str}"
        )

    def test_empty_layers_raises(self):
        """空图层列表抛出 ValueError。"""
        svc = _make_service()
        with pytest.raises(ValueError, match="没有可渲染的图层"):
            svc._build_filter_complex([])


# ── 测试 render 方法 ─────────────────────────────────────────────────────────


class TestRender:
    """测试 render 方法。"""

    def test_render_empty_clips_raises(self):
        """没有 clips 时抛出 ValueError。"""
        svc = _make_service(clips=[], asset_paths={})
        with pytest.raises(ValueError, match="没有可渲染的片段"):
            svc.render()

    def test_render_with_missing_assets_raises(self):
        """所有 clips 素材缺失时抛出 ValueError。"""
        clips = [_make_clip("c1", "main", order=0, asset_id="missing.mp4")]
        svc = _make_service(clips, asset_paths={})
        with pytest.raises(ValueError, match="没有可渲染的片段"):
            svc.render()

    def test_render_success(self):
        """正常渲染流程。"""
        clips = [_make_clip("c1", "main", order=0)]
        asset_paths = {"asset_c1.mp4": Path("/tmp/asset_c1.mp4")}
        svc = _make_service(clips, asset_paths)

        with (
            _patch_path_exists(),
            patch("video_processing.unified_render_service.probe_duration", return_value=5.0),
            patch.object(svc, "_execute_ffmpeg") as mock_exec,
            patch.object(svc, "_probe_output", return_value=(5.0, 1024, 1280, 720)),
        ):
            result = svc.render()

        assert isinstance(result, RenderResult)
        assert result.duration == 5.0
        assert result.file_size == 1024
        assert result.width == 1280
        assert result.height == 720
        mock_exec.assert_called_once()