from contextlib import ExitStack
"""Plot capture follows client demand and actual Qt scene changes."""

from collections import deque
import unittest
from unittest import mock

import numpy as np
from PyQt6.QtCore import QSignalBlocker
from PyQt6.QtWidgets import QApplication, QComboBox

from python_app.tests.gui_test_support import isolated_window


class WebPlotCaptureTest(unittest.TestCase):
    @classmethod
    def setUpClass(cls) -> None:
        cls.app = QApplication.instance() or QApplication([])
        cls.window = isolated_window(cls.addClassCleanup)
        cls.window._pipeline.timer.stop()
        cls.window._pipeline.replay.timer.stop()
        cls.window.show()

    def setUp(self) -> None:
        cleanup = ExitStack()
        self.addCleanup(cleanup.close)
        self.w = self.window
        self.web = self.w._web
        self.web.set_frame_streaming(False)
        self.grab = cleanup.enter_context(mock.patch.object(self.web, "_grab_png", wraps=self.web._grab_png))

    def settle(self) -> None:
        # Initial paints can settle the axis layout over several Qt event turns.
        for _ in range(10):
            self.app.processEvents()
            self.web._last_grab_s = 0
            self.web._grab_frame_if_due()

    def test_no_clients_never_grabs_and_first_client_gets_current_plot(self) -> None:
        self.w._plots.bscan.widget.plot([0, 1], [1, 2])
        self.settle()
        self.grab.assert_not_called()
        controller = self.web
        mode = self.w._view.processing.mode
        with QSignalBlocker(mode):
            mode.setCurrentText("bscan")
        self.w._live.active_mode = "bscan"
        self.w._plots.bscan.history_by_combo = {(2, 3): deque([np.array([1., 2.])])}
        self.w._plots.sync_display_combos()
        self.web.refresh_snapshot()
        self.assertEqual(controller.status()["display_combo"],
                         {"enabled": True, "input": 2, "output": 3, "options": [(2, 3)]})
        self.grab.assert_not_called()
        controller.set_frame_streaming(True)
        self.settle()
        self.assertGreater(self.grab.call_count, 0)
        self.assertIsNotNone(self.web._last_png)
        calls = self.grab.call_count
        self.settle()
        self.assertEqual(self.grab.call_count, calls)  # grab does not keep itself dirty
        controller.set_frame_streaming(False)
        self.w._plots.bscan.widget.clear()
        self.settle()
        self.assertEqual(self.grab.call_count, calls)

    def test_data_clear_zoom_resize_and_sar_grid_trigger_capture_after_idle(self) -> None:
        self.web.set_frame_streaming(True)
        plot = self.w._plots.bscan.widget
        item = plot.getPlotItem()
        assert item is not None
        view = item.getViewBox()
        self.w._plots.stack.setCurrentWidget(plot)
        self.settle()
        actions = [
            lambda: plot.plot([0, 1, 2], [1, 4, 2]),
            lambda: view.setXRange(0.25, 1.5, padding=0),
            plot.clear,
            lambda: self.w.resize(self.w.width() + 50, self.w.height() + 50),
            lambda: self.w._plots.stack.setCurrentWidget(self.w._plots.sar3d.widget),
        ]
        actions.extend(lambda plot=plot: plot.plot([0, 1], [1, 3]) for plot in self.w._plots.sar3d.plots.values())
        for action in actions:
            with self.subTest(action=action):
                calls = self.grab.call_count
                action()
                self.settle()
                self.assertGreater(self.grab.call_count, calls)
        calls = self.grab.call_count
        self.settle()
        self.assertEqual(self.grab.call_count, calls)

    def test_throttle_keeps_dirty_and_ignores_changes_emitted_during_grab(self) -> None:
        self.web.set_frame_streaming(True)
        self.settle()
        self.web._mark_dirty()
        self.web._last_grab_s = 100
        with mock.patch("python_app.gui.controllers.web_controller.time.monotonic", return_value=100.1):
            self.assertIsNone(self.web._grab_frame_if_due())
        self.assertTrue(self.web._dirty)
        self.grab.side_effect = lambda: (self.web._mark_dirty(), "changed-png")[1]
        with mock.patch("python_app.gui.controllers.web_controller.time.monotonic", return_value=100.3):
            self.assertIsNotNone(self.web._grab_frame_if_due())
        self.assertFalse(self.web._dirty)


if __name__ == "__main__":
    unittest.main()