"""R2 C3/C5/C6 in a real DOM: in-place judgment.

A TestClient can prove what the server answers. It cannot prove that a flag
made in the page lands without a reload, that the regions come back fresh, or
that a failure never re-POSTs. So: a real uvicorn, a real Chromium — the same
harness as test_embed_browser.py, and like it this SKIPS, never fails, when no
browser is available.
"""
import pathlib
import socket
import sys
import threading
import time

import pytest

sys.path.insert(0, str(pathlib.Path(__file__).parent.parent))

from booth.app import create_app  # noqa: E402

playwright_api = pytest.importorskip("playwright.sync_api", reason="playwright is not installed")

PNG = b"\x89PNG\r\n\x1a\n"


@pytest.fixture(scope="module")
def browser():
    with playwright_api.sync_playwright() as pw:
        try:
            b = pw.chromium.launch()
        except Exception as exc:  # noqa: BLE001 - any launch failure is a skip
            pytest.skip(f"no usable chromium: {exc}")
        yield b
        b.close()


@pytest.fixture
def live(tmp_path):
    import uvicorn

    sock = socket.socket()
    sock.bind(("127.0.0.1", 0))
    port = sock.getsockname()[1]
    sock.close()
    app = create_app(tmp_path, ttl_hours=24, start_sweeper=False)
    server = uvicorn.Server(uvicorn.Config(app, host="127.0.0.1", port=port, log_level="error"))
    thread = threading.Thread(target=server.run, daemon=True)
    thread.start()
    deadline = time.time() + 10
    while not server.started and time.time() < deadline:
        time.sleep(0.02)
    if not server.started:
        pytest.skip("uvicorn did not come up")
    try:
        yield f"http://127.0.0.1:{port}", tmp_path
    finally:
        server.should_exit = True
        thread.join(timeout=10)


def _set(root: pathlib.Path, n: int = 30) -> pathlib.Path:
    b = root / "g"
    b.mkdir()
    for i in range(1, n + 1):
        (b / f"{i:02d}.png").write_bytes(PNG)
    return b


def test_a_flag_lands_in_place_and_every_region_catches_up(browser, live):
    """Click a tile's flag far down the page: no reload, the scroll position
    holds, and the tile, the tray and the rail's count all show the server's
    new state — the three places one flag appears."""
    base, root = live
    _set(root)
    posts = []
    page = browser.new_page(viewport={"width": 1400, "height": 800})
    page.on("request", lambda r: posts.append(r.url) if r.method == "POST" else None)
    page.goto(f"{base}/b/g/", wait_until="networkidle")
    page.evaluate("window.__noReload = 1")
    tile = page.locator('figure.item[data-item="24.png"]')
    tile.scroll_into_view_if_needed()
    y = page.evaluate("window.scrollY")
    tile.locator(".flagtoggle button").click()
    page.wait_for_selector('figure.item.is-flagged[data-item="24.png"]', timeout=10000)
    state = page.evaluate("""() => ({
        reload: window.__noReload !== 1,
        y: window.scrollY,
        tray: [...document.querySelectorAll('.tray .tray-ord')].map(e => e.textContent),
        count: document.querySelector('.rail-f[data-filter="flagged"] b').textContent,
    })""")
    page.close()
    assert not state["reload"]
    assert abs(state["y"] - y) < 4, "the page must not jump"
    assert state["tray"] == ["#24"]
    assert state["count"] == "1"
    assert len(posts) == 1


def test_a_failed_save_says_so_reloads_and_never_re_posts(browser, live):
    """The server refuses the write (the marks file went bad under the page).
    The script must not retry — a retry after a lost response would duplicate
    the judgment — it says so and reloads to show the server's truth."""
    base, root = live
    b = _set(root, 3)
    posts = []
    page = browser.new_page()
    page.on("request", lambda r: posts.append(r.url) if r.method == "POST" else None)
    page.goto(f"{base}/b/g/", wait_until="networkidle")
    (b / ".marks.json").write_text("{damaged")
    with page.expect_navigation(timeout=10000):
        page.locator('figure.item[data-item="01.png"] .flagtoggle button').click()
    page.wait_for_load_state("networkidle")
    page.close()
    assert len(posts) == 1, f"re-POSTed: {posts}"