"""P2 验收链路：mock 宿主上"导入 → 铺轨 → 切/重建 → 删除 → 加效果 → 取帧验证 →
整段会话撤销"全链路自动化通过（计划文档 §4 P2 验收）。

关键断言：帧非全黑、编辑前后切口帧像素不同、undo_session 后时间线恢复原状。
"""
import hashlib

from mock_host import MockHostAdapter, decode_png, frame_is_black
from quercus_core.tools.executor import HostToolExecutor
from quercus_core.types import Action, Rational

FRAME_SIZE = {"width": 64, "height": 36}


def r(x: int) -> dict:
    return {"num": x, "den": 1}


def _frame_at(executor, t_json, size=FRAME_SIZE):
    result = executor.execute(Action(tool="get_frame", params={"time": t_json, "max_size": size}))
    assert result.ok, f"get_frame 失败: {result.summary}"
    assert len(result.images) == 1
    return result.images[0]


def _sha(png: bytes) -> str:
    return hashlib.sha256(png).hexdigest()


def _first_clips(adapter):
    seq_id = adapter.get_project_overview().timeline_ids[0]
    return adapter.get_timeline_structure(seq_id).tracks[0].clips


def test_p2_acceptance_chain():
    adapter = MockHostAdapter()
    executor = HostToolExecutor(adapter)

    def act(tool, **params):
        result = executor.execute(Action(tool=tool, params=params))
        assert result.ok, f"{tool} 失败: {result.summary}"
        return result

    # 1) 导入两个素材
    act("import_footage", paths=["/media/alpha.mp4", "/media/beta.mp4"])
    footage = {it["name"]: it["id"] for it in adapter.list_footage()}
    f_alpha = footage["alpha.mp4"]
    f_beta = footage["beta.mp4"]

    # 2) 铺轨：alpha[0,4) + beta[4,8)
    act("place_clip", clip_id=f_alpha, track_index=1, time=r(0), in_point=r(0), out_point=r(4))
    act("place_clip", clip_id=f_beta, track_index=1, time=r(4), in_point=r(0), out_point=r(4))
    clip_a = _first_clips(adapter)[0]

    # 3) 切口帧（编辑前）：t=3 处是 alpha 的画面
    frame_before = _frame_at(executor, r(3))
    assert not frame_is_black(frame_before, 64, 36), "编辑前切口帧不得全黑"
    decode_png(frame_before)  # 必须是合法 PNG

    # 4) 在 t=2 处切开 alpha
    act("split_clip", clip_id=clip_a.id, time=r(2))
    right_half = next(c for c in _first_clips(adapter) if c.start == Rational(2))

    # 5) 波纹删除右半段 → beta 前移到 [2,6)
    act("ripple_delete", clip_ids=[right_half.id])
    frame_after_cut = _frame_at(executor, r(3))
    assert not frame_is_black(frame_after_cut, 64, 36)
    # 编辑前后切口帧像素不同（beta 代替了 alpha 出现在 t=3）
    assert _sha(frame_after_cut) != _sha(frame_before), "切口帧像素应随编辑变化"

    # 6) 给 beta 加效果并设参数 → 画面再变
    beta_clip = next(c for c in _first_clips(adapter) if c.source == f_beta)
    act("add_effect", clip_id=beta_clip.id, effect_type="brightness")
    node_id = adapter._must_clip(beta_clip.id).effects[0].node_id  # 白盒取节点
    act("set_param", effect_id=node_id, param="level", value=0.5)
    frame_after_effect = _frame_at(executor, r(3))
    assert not frame_is_black(frame_after_effect, 64, 36)
    assert _sha(frame_after_effect) != _sha(frame_after_cut), "加效果后画面应改变"

    # 7) 整段会话撤销 → 时间线恢复原状（回到首个变更批次之前：空）
    restored = executor.undo_session()
    assert restored >= 6, f"应撤销 ≥6 个批次，实际 {restored}"
    overview = adapter.get_project_overview()
    assert overview.timeline_ids == []  # 无时间线 = 铺轨前的原状
    assert adapter.list_footage() == []  # 连导入也被撤销（快照覆盖首个批次）