"""Verifies the sync preview feature: building a short offset-corrected
clip and playing it in a popup PreviewDialog, plus the Sync markers panel
now showing Mark Audio Event before Mark Video Event with a Detect All
Claps button alongside them.

PreviewDialog.exec() is a real modal event loop, which would block this
script's own flow with no way to close it from inside. Monkeypatches it to
show() non-modally instead (capturing the instance) purely for test
purposes -- production code still calls the real modal .exec().
"""
import sys
import time
from pathlib import Path

from PyQt6.QtWidgets import QApplication

sys.path.insert(0, str(Path(__file__).resolve().parent.parent))
import main as app_main

ROOT = Path(__file__).resolve().parent.parent
CLIP = str(ROOT / "test_media" / "sync_test_OUTOFSYNC_audio+350ms.mp4")


def main():
    qapp = QApplication(sys.argv)

    # -- Marker panel order: Mark Audio Event before Mark Video Event, with
    # Detect All Claps in the same panel.
    win = app_main.MainWindow()
    win.show()
    qapp.processEvents()

    marker_layout = win.mark_audio_button.parentWidget().layout()
    widgets = [marker_layout.itemAt(i).widget() for i in range(marker_layout.count())]
    widgets = [w for w in widgets if w is not None]
    audio_idx = widgets.index(win.mark_audio_button)
    video_idx = widgets.index(win.mark_video_button)
    detect_idx = widgets.index(win.detect_all_button)
    assert audio_idx < video_idx, "Mark Audio Event should come before Mark Video Event"
    assert win.detect_all_button in widgets, "Detect All Claps button should be in the same panel"
    print(f"PASS: marker panel order is audio({audio_idx}) < video({video_idx}), detect button present at {detect_idx}")

    # -- Preview: mark both events on the known-shifted fixture, build a
    # preview clip, and confirm it plays back with the events much closer
    # together than the original 350ms.
    captured = {}

    def fake_exec(self):
        captured["dialog"] = self
        # This is the only point guaranteed to run before the real
        # _on_preview_ready's cleanup (os.unlink) fires -- a real .exec()
        # would block here until the dialog closes, but this fake returns
        # immediately, so the app's own cleanup-after-exec() code runs
        # right after this function returns, whether or not the dialog is
        # still visually open. Check existence here, not after.
        captured["existed_while_open"] = Path(win._preview_temp_path).exists()
        self.show()
        return 0

    app_main.PreviewDialog.exec = fake_exec

    win._load(CLIP)
    qapp.processEvents()
    time.sleep(0.2)
    qapp.processEvents()

    win.player.seek(5.000)
    qapp.processEvents()
    win._mark_video()

    win.player.seek(5.350)
    qapp.processEvents()
    win._mark_audio()

    assert win.preview_button.isEnabled()

    win.preview_button.click()
    qapp.processEvents()
    assert not win.preview_button.isEnabled(), "preview button should disable while building"
    temp_path_ref = win._preview_temp_path
    print(f"building preview clip at: {temp_path_ref}")

    deadline = time.time() + 20
    while "dialog" not in captured and time.time() < deadline:
        qapp.processEvents()
        time.sleep(0.05)

    assert "dialog" in captured, "preview dialog was never shown"
    dialog = captured["dialog"]
    qapp.processEvents()
    time.sleep(0.3)
    qapp.processEvents()

    duration = dialog.player.mpv.duration
    print(f"preview clip duration: {duration:.3f}s (expected ~{win.PREVIEW_DURATION_SEC}s, clamped to file bounds)")
    assert duration is not None and 0 < duration <= win.PREVIEW_DURATION_SEC + 0.5

    assert captured["existed_while_open"], "temp preview file should have existed while the dialog was showing"

    dialog.close()
    qapp.processEvents()
    time.sleep(0.2)
    qapp.processEvents()

    assert not Path(temp_path_ref).exists(), "temp preview file should be cleaned up after the (real) exec() returns"
    print("PASS: preview clip built, played, and cleaned up correctly")

    win.player.shutdown()
    print("\nPREVIEW SMOKE TEST PASSED")


if __name__ == "__main__":
    main()