// ==UserScript==
// @name         Dangqi Piaopiao Auto Runner
// @namespace    https://github.com/
// @version      1.0.1
// @description  自动轮播当前课程视频、跳过提示并提供可配置悬浮面板。
// @author       GitHub Copilot
// @match        https://dangqipiaopiao.*.edu.cn/*
// @grant        none
// @run-at       document-idle
// ==/UserScript==

(function () {
	'use strict';

	const COOKIE_NAME = 'dqpp_auto_settings';
	const COOKIE_MAX_AGE = 60 * 60 * 24 * 365; // 365 天
	const PANEL_ID = 'dqpp-auto-panel';
	const PANEL_STYLE_ID = 'dqpp-auto-panel-style';
	const LOG_MAX_ENTRIES = 60;
	const ALERT_AUDIO_URL = 'https://cdn.pixabay.com/audio/2023/10/22/audio_107003231b.mp3';

	const SELECTORS = {
		finishModal: 'body > div.public_cont.public_cont1',
		finishButton: 'div.public_btn > a',
		introModal: 'div.public_cont:not(.public_cont1)',
		introSubmit: '.public_submit',
		progressCancel: '.public_cancel',
		playerElapsed: 'div.plyr__controls__item:nth-child(2)',
		playerRemaining: 'div.plyr__controls__item:nth-child(3)',
		playlistDuration: 'li.video_red1 > span:nth-child(2)',
		playerContainer: '#wrapper.video_play1 .plyr',
		playerPoster: '#wrapper.video_play1 .plyr__poster',
	};

	const defaultSettings = {
		autoPlayNext: false,
		skipIntro: false,
		running: false,
		delayMin: 1,
		delayMax: 2,
		panelPosition: {
			top: '120px',
			left: '24px',
		},
	};

	let settings = loadSettings();
	let isRunning = false;
	let loopTimer = null;
	let loopBusy = false;
	let nextClickScheduled = false;
	let readyToAdvance = false;
	const logs = [];
	let pauseResumeAttempts = 0;
	let pauseResumeBlocked = false;
	let alertAudio = null;
	const operationFailureCounter = Object.create(null);

	const uiState = {
		panel: null,
		status: null,
		runButton: null,
		stopButton: null,
		autoNextCheckbox: null,
		skipIntroCheckbox: null,
		delayMinInput: null,
		delayMaxInput: null,
		logList: null,
		logEmpty: null,
	};

	whenReady(() => {
		injectPanelStyle();
		buildPanel();
		applySettingsToPanel();
		prepareAlertAudio();
		if (settings.running) {
			startAutomation(true);
		} else {
			setStatusMessage('待命');
		}
	});

	function whenReady(callback) {
		if (document.readyState === 'loading') {
			document.addEventListener('DOMContentLoaded', callback, { once: true });
		} else {
			callback();
		}
	}

	function injectPanelStyle() {
		if (document.getElementById(PANEL_STYLE_ID)) return;
		const style = document.createElement('style');
		style.id = PANEL_STYLE_ID;
		style.textContent = `
			#${PANEL_ID} {
				position: fixed;
				top: ${settings.panelPosition.top};
				left: ${settings.panelPosition.left};
				width: 260px;
				background: rgba(17, 24, 39, 0.95);
				color: #f8fafc;
				font-family: 'Segoe UI', 'PingFang SC', sans-serif;
				font-size: 12px;
				border-radius: 10px;
				box-shadow: 0 15px 35px rgba(15, 23, 42, 0.35);
				z-index: 600000;
				backdrop-filter: blur(6px);
				line-height: 1.5;
				user-select: none;
			}
			#${PANEL_ID} header {
				display: flex;
				align-items: center;
				justify-content: space-between;
				padding: 10px 14px;
				cursor: move;
				font-weight: 600;
				border-bottom: 1px solid rgba(148, 163, 184, 0.25);
			}
			#${PANEL_ID} header span {
				font-size: 13px;
			}
			#${PANEL_ID} .dqpp-status {
				font-size: 11px;
				color: #22d3ee;
			}
			#${PANEL_ID} main {
				padding: 12px 14px 14px;
				display: flex;
				flex-direction: column;
				gap: 10px;
			}
			#${PANEL_ID} label {
				display: flex;
				align-items: center;
				gap: 6px;
				cursor: pointer;
			}
			#${PANEL_ID} input[type="checkbox"] {
				accent-color: #38bdf8;
			}
			#${PANEL_ID} .dqpp-field {
				display: flex;
				gap: 6px;
				align-items: center;
			}
			#${PANEL_ID} .dqpp-field input[type="number"] {
				flex: 1;
				width: 70px;
				padding: 4px 6px;
				border: 1px solid rgba(148, 163, 184, 0.4);
				border-radius: 6px;
				background: rgba(15, 23, 42, 0.7);
				color: #f1f5f9;
				outline: none;
			}
			#${PANEL_ID} .dqpp-field input[type="number"]:focus {
				border-color: #38bdf8;
				box-shadow: 0 0 0 2px rgba(56, 189, 248, 0.2);
			}
			#${PANEL_ID} footer {
				display: flex;
				gap: 10px;
				padding: 10px 14px 14px;
			}
			#${PANEL_ID} button {
				flex: 1;
				padding: 8px 0;
				border-radius: 6px;
				border: none;
				cursor: pointer;
				font-weight: 600;
				font-size: 12px;
				transition: transform 0.15s ease, box-shadow 0.15s ease;
			}
			#${PANEL_ID} button:active {
				transform: translateY(1px);
			}
			#${PANEL_ID} .dqpp-btn-run {
				background: linear-gradient(135deg, #38bdf8, #22d3ee);
				color: #0f172a;
				box-shadow: 0 10px 20px rgba(34, 211, 238, 0.25);
			}
			#${PANEL_ID} .dqpp-btn-stop {
				background: linear-gradient(135deg, #f43f5e, #fb7185);
				color: #fff1f2;
				box-shadow: 0 10px 20px rgba(244, 63, 94, 0.25);
			}
			#${PANEL_ID} .dqpp-note {
				font-size: 11px;
				color: rgba(226, 232, 240, 0.7);
			}
			#${PANEL_ID} .dqpp-test-audio {
				padding: 4px 8px;
				font-size: 11px;
				border-radius: 4px;
				border: 1px solid rgba(148, 163, 184, 0.4);
				background: rgba(15, 23, 42, 0.7);
				color: #f1f5f9;
				cursor: pointer;
				transition: all 0.15s ease;
			}
			#${PANEL_ID} .dqpp-test-audio:hover {
				background: rgba(59, 130, 246, 0.2);
				border-color: #3b82f6;
			}
			#${PANEL_ID} .dqpp-log {
				display: flex;
				flex-direction: column;
				gap: 6px;
				border-top: 1px solid rgba(148, 163, 184, 0.2);
				padding-top: 8px;
				max-height: 160px;
			}
			#${PANEL_ID} .dqpp-log-title {
				font-size: 11px;
				font-weight: 600;
				letter-spacing: 0.02em;
				color: rgba(148, 197, 253, 0.9);
			}
			#${PANEL_ID} .dqpp-log-list {
				flex: 1;
				overflow-y: auto;
				padding-right: 4px;
				display: flex;
				flex-direction: column;
				gap: 4px;
				scrollbar-width: thin;
			}
			#${PANEL_ID} .dqpp-log-list::-webkit-scrollbar {
				width: 6px;
			}
			#${PANEL_ID} .dqpp-log-list::-webkit-scrollbar-thumb {
				background: rgba(148, 163, 184, 0.25);
				border-radius: 4px;
			}
			#${PANEL_ID} .dqpp-log-entry {
				display: flex;
				gap: 6px;
				align-items: flex-start;
				font-size: 11px;
				line-height: 1.4;
				color: rgba(226, 232, 240, 0.85);
			}
			#${PANEL_ID} .dqpp-log-entry time {
				font-variant-numeric: tabular-nums;
				color: rgba(148, 163, 184, 0.8);
				flex-shrink: 0;
			}
			#${PANEL_ID} .dqpp-log-empty {
				font-size: 11px;
				color: rgba(148, 163, 184, 0.6);
			}
		`;
		document.head.appendChild(style);
	}

	function buildPanel() {
		if (document.getElementById(PANEL_ID)) {
			uiState.panel = document.getElementById(PANEL_ID);
			return;
		}

		const panel = document.createElement('section');
		panel.id = PANEL_ID;
		panel.innerHTML = `
			<header>
				<span>视频助手</span>
				<span class="dqpp-status">...</span>
			</header>
			<main>
				<label>
					<input type="checkbox" data-opt="autoPlayNext" />
					结束后自动播放下一个视频
				</label>
				<label>
					<input type="checkbox" data-opt="skipIntro" />
					跳过片头提示
				</label>
				<div class="dqpp-field">
					<span>随机延迟 (秒)</span>
				</div>
				<div class="dqpp-field">
					<input type="number" step="0.1" min="0" data-opt="delayMin" placeholder="最小值" />
					<span>~</span>
					<input type="number" step="0.1" min="0" data-opt="delayMax" placeholder="最大值" />
				</div>
				<p class="dqpp-note">随机延迟将在所有自动点击时生效，默认 1~2 秒。</p>
				<div class="dqpp-field">
					<button type="button" class="dqpp-test-audio">测试提示音</button>
				</div>
				<div class="dqpp-log">
					<div class="dqpp-log-title">操作记录</div>
					<div class="dqpp-log-list"></div>
					<div class="dqpp-log-empty">暂无日志</div>
				</div>
			</main>
			<footer>
				<button type="button" class="dqpp-btn-run">运行</button>
				<button type="button" class="dqpp-btn-stop">停止</button>
			</footer>
		`;

		document.body.appendChild(panel);

		uiState.panel = panel;
		uiState.status = panel.querySelector('.dqpp-status');
		uiState.runButton = panel.querySelector('.dqpp-btn-run');
		uiState.stopButton = panel.querySelector('.dqpp-btn-stop');
		uiState.logList = panel.querySelector('.dqpp-log-list');
		uiState.logEmpty = panel.querySelector('.dqpp-log-empty');
		const controls = panel.querySelectorAll('[data-opt]');
		controls.forEach((el) => {
			const key = el.getAttribute('data-opt');
			if (key === 'autoPlayNext') uiState.autoNextCheckbox = el;
			if (key === 'skipIntro') uiState.skipIntroCheckbox = el;
			if (key === 'delayMin') uiState.delayMinInput = el;
			if (key === 'delayMax') uiState.delayMaxInput = el;

			el.addEventListener('change', () => handlePanelInputChange(el, key));
		});

		uiState.runButton.addEventListener('click', () => startAutomation());
		uiState.stopButton.addEventListener('click', () => stopAutomation());

		// 添加测试音频按钮事件监听器
		const testAudioButton = panel.querySelector('.dqpp-test-audio');
		if (testAudioButton) {
			testAudioButton.addEventListener('click', () => {
				playAlertSound('测试提示音播放');
			});
		}

		makePanelDraggable(panel.querySelector('header'));
		renderLogs();
	}

	function makePanelDraggable(handle) {
		if (!handle || !uiState.panel) return;

		let isDragging = false;
		let offsetX = 0;
		let offsetY = 0;

		handle.addEventListener('mousedown', (event) => {
			if (event.button !== 0) return;
			isDragging = true;
			const rect = uiState.panel.getBoundingClientRect();
			offsetX = event.clientX - rect.left;
			offsetY = event.clientY - rect.top;
			document.addEventListener('mousemove', onMouseMove);
			document.addEventListener('mouseup', onMouseUp, { once: true });
		});

		function onMouseMove(event) {
			if (!isDragging) return;
			const newLeft = Math.max(0, event.clientX - offsetX);
			const newTop = Math.max(0, event.clientY - offsetY);
			uiState.panel.style.left = `${newLeft}px`;
			uiState.panel.style.top = `${newTop}px`;
		}

		function onMouseUp() {
			isDragging = false;
			document.removeEventListener('mousemove', onMouseMove);
			savePanelPosition();
		}
	}

	function handlePanelInputChange(element, key) {
		if (!key) return;
		let value;

		if (element.type === 'checkbox') {
			value = element.checked;
		} else if (element.type === 'number') {
			value = element.value;
		} else {
			value = element.value;
		}

		if (key === 'delayMin' || key === 'delayMax') {
			const numeric = clampDelayValue(parseFloat(value));
			element.value = numeric;
			value = numeric;
		}

		settings = {
			...settings,
			[key]: value,
		};

		ensureDelayOrder();
		saveSettings();
	 	logSettingChange(key);

		if (key === 'skipIntro' && settings.skipIntro) {
			setStatusMessage('已开启跳过片头');
		}
	}

	function applySettingsToPanel() {
		if (!uiState.panel) return;
		uiState.panel.style.top = settings.panelPosition.top;
		uiState.panel.style.left = settings.panelPosition.left;

		if (uiState.autoNextCheckbox) {
			uiState.autoNextCheckbox.checked = Boolean(settings.autoPlayNext);
		}
		if (uiState.skipIntroCheckbox) {
			uiState.skipIntroCheckbox.checked = Boolean(settings.skipIntro);
		}
		if (uiState.delayMinInput) {
			uiState.delayMinInput.value = settings.delayMin;
		}
		if (uiState.delayMaxInput) {
			uiState.delayMaxInput.value = settings.delayMax;
		}
		updateRunButtons();
		renderLogs();
	}

	function updateRunButtons() {
		if (!uiState.runButton || !uiState.stopButton) return;
		uiState.runButton.disabled = isRunning;
		uiState.stopButton.disabled = !isRunning;
	}

	function setStatusMessage(message, options) {
		if (uiState.status) uiState.status.textContent = message;
		if (!message) return;
		const { log = true, type = 'info' } = options || {};
		if (log) {
			appendLog(message, type);
		}
	}

	function appendLog(message, type = 'info') {
		const entry = {
			id: `${Date.now()}-${Math.random().toString(36).slice(2, 8)}`,
			timestamp: new Date(),
			message: String(message),
			type,
		};
		logs.push(entry);
		while (logs.length > LOG_MAX_ENTRIES) {
			logs.shift();
		}
		renderLogs();
	}

	function renderLogs() {
		if (!uiState.logList) return;
		uiState.logList.innerHTML = '';
		if (!logs.length) {
			if (uiState.logEmpty) uiState.logEmpty.style.display = 'block';
			return;
		}

		if (uiState.logEmpty) uiState.logEmpty.style.display = 'none';
		const fragment = document.createDocumentFragment();
		for (const entry of logs) {
			const row = document.createElement('div');
			row.className = `dqpp-log-entry dqpp-log-entry--${entry.type}`;
			row.dataset.entryId = entry.id;

			const timeEl = document.createElement('time');
			timeEl.textContent = formatLogTimestamp(entry.timestamp);

			const messageEl = document.createElement('span');
			messageEl.textContent = entry.message;

			row.appendChild(timeEl);
			row.appendChild(messageEl);
			fragment.appendChild(row);
		}
		uiState.logList.appendChild(fragment);
		uiState.logList.scrollTop = uiState.logList.scrollHeight;
	}

	function formatLogTimestamp(date) {
		if (!(date instanceof Date)) return '';
		const pad = (value) => String(value).padStart(2, '0');
		const hours = pad(date.getHours());
		const minutes = pad(date.getMinutes());
		const seconds = pad(date.getSeconds());
		return `${hours}:${minutes}:${seconds}`;
	}

	function startAutomation(isAutoStart = false) {
		if (isRunning) return;
		isRunning = true;
		settings.running = true;
		saveSettings();
		updateRunButtons();
		setStatusMessage(isAutoStart ? '自动恢复运行中…' : '运行中');

		if (loopTimer) clearInterval(loopTimer);
		loopTimer = setInterval(runAutomationTick, 1500);
		runAutomationTick();
	}

	function stopAutomation() {
		if (!isRunning) return;
		isRunning = false;
		settings.running = false;
		saveSettings();
		updateRunButtons();
		setStatusMessage('已停止');

		if (loopTimer) {
			clearInterval(loopTimer);
			loopTimer = null;
		}
	}

	function runAutomationTick() {
		if (!isRunning || loopBusy) return;
		loopBusy = true;

		try {
			if (settings.skipIntro) {
				handleIntroModal();
			}

			const handledFinish = handleFinishModal();
			if (!handledFinish) {
				handlePausedPlayback();
				if (settings.autoPlayNext) {
					maybeScheduleNextVideo();
				}
			}
		} finally {
			loopBusy = false;
		}
	}

	function handleIntroModal() {
		const introModal = document.querySelector(SELECTORS.introModal);
		if (!introModal) return false;
		if (introModal.dataset.dqppSkipHandled === '1') return true;

		const submitButton = introModal.querySelector(SELECTORS.introSubmit);
		if (!submitButton) return false;

		introModal.dataset.dqppSkipHandled = '1';
		const delay = randomDelayMs();
		setStatusMessage(`检测到片头提示，将在 ${(delay / 1000).toFixed(1)}s 内跳过…`);

			setTimeout(() => {
				if (!settings.skipIntro) return;
				safeClick(submitButton);
				setStatusMessage('已尝试跳过片头');
		}, delay);

		return true;
	}

		function handleFinishModal() {
			const finishModal = document.querySelector(SELECTORS.finishModal);
			if (!finishModal) {
				readyToAdvance = false;
				return false;
			}

			const handledState = finishModal.dataset.dqppFinishHandled;
			if (handledState && handledState !== 'closing' && !isElementVisible(finishModal)) {
				delete finishModal.dataset.dqppFinishHandled;
			}

			if (handledState === 'closing') {
				return true;
			}

			if (finishModal.dataset.dqppFinishHandled === '1') {
				return true;
			}

			if (!isElementVisible(finishModal)) {
				return false;
			}

			const finishButton = finishModal.querySelector(SELECTORS.finishButton);
			const cancelButton = finishModal.querySelector(SELECTORS.progressCancel);

			const modalType = classifyPlaybackModal(finishModal);
			const isFinished = modalType === 'finished';
			finishModal.dataset.dqppFinishHandled = '1';
			readyToAdvance = isFinished;

			const actionButton = modalType === 'progress' && cancelButton ? cancelButton : finishButton;
			if (!actionButton) return false;

			const delayBase = isFinished ? 2000 : 500;
			const delay = delayBase + randomDelayMs();
			const nextTarget = isFinished && settings.autoPlayNext ? getNextVideoUrl() : null;

			switch (modalType) {
				case 'finished':
					setStatusMessage(`检测到播放完成，将在 ${(delay / 1000).toFixed(1)}s 后关闭提示…`);
					break;
				case 'intro':
					setStatusMessage(`检测到播放须知，${(delay / 1000).toFixed(1)}s 后继续播放`);
					break;
				case 'paused':
					setStatusMessage(`检测到自动暂停提示，${(delay / 1000).toFixed(1)}s 后继续`);
					break;
				case 'progress':
					setStatusMessage(`检测到进度提示，${(delay / 1000).toFixed(1)}s 后关闭`);
					break;
				default:
					setStatusMessage(`检测到提示窗口，${(delay / 1000).toFixed(1)}s 后确认`);
			}

			setTimeout(() => {
				safeClick(actionButton);
				finishModal.dataset.dqppFinishHandled = 'closing';
				if (isFinished && isRunning && settings.autoPlayNext) {
					if (nextTarget) {
						scheduleNextVideoNavigation(nextTarget);
					} else {
						setStatusMessage('全部视频已播放完毕');
						readyToAdvance = false;
						nextClickScheduled = false;
					}
				} else if (!isFinished) {
					if (modalType === 'progress') {
						setStatusMessage('已关闭进度提示');
					} else {
						setStatusMessage('已尝试恢复播放');
					}
				}
				setTimeout(() => {
					if (finishModal && finishModal.dataset) {
						delete finishModal.dataset.dqppFinishHandled;
					}
				}, 2000);
			}, delay);

			return true;
		}

		function handlePausedPlayback() {
			const player = document.querySelector(SELECTORS.playerContainer);
			if (!player) return false;

			const isPaused = player.classList.contains('plyr--paused');
			const isPlaying = player.classList.contains('plyr--playing');

			if (isPlaying || !isPaused) {
				pauseResumeAttempts = 0;
				pauseResumeBlocked = false;
				markOperationResult('autoResume', true);
				if (player.dataset.dqppResumeHandled) {
					delete player.dataset.dqppResumeHandled;
				}
				return false;
			}

			if (pauseResumeBlocked || player.dataset.dqppResumeHandled === 'blocked') {
				return false;
			}

			const finishModal = document.querySelector(SELECTORS.finishModal);
			if (finishModal && isElementVisible(finishModal)) {
				return false;
			}

			if (player.dataset.dqppResumeHandled === '1') {
				return true;
			}

			if (pauseResumeAttempts >= 3) {
				pauseResumeBlocked = true;
				player.dataset.dqppResumeHandled = 'blocked';
				setStatusMessage('自动续播已尝试 3 次未成功，停止自动恢复', { type: 'warn' });
				markOperationResult('autoResume', false, '自动续播尝试 3 次仍未成功');
				return false;
			}

			pauseResumeAttempts += 1;

			const delay = randomDelayMs();
			setStatusMessage(
				`检测到暂停，第 ${pauseResumeAttempts} 次将在 ${(delay / 1000).toFixed(1)}s 后尝试继续播放`,
			);
			player.dataset.dqppResumeHandled = '1';

			setTimeout(() => {
				const livePlayer = document.querySelector(SELECTORS.playerContainer);
				if (!isRunning || !livePlayer) {
					if (player.dataset) {
						delete player.dataset.dqppResumeHandled;
					}
					return;
				}

				if (!livePlayer.classList.contains('plyr--paused')) {
					delete livePlayer.dataset.dqppResumeHandled;
					pauseResumeAttempts = 0;
					pauseResumeBlocked = false;
					markOperationResult('autoResume', true);
					return;
				}

				focusPlayerArea();

				const focused = document.activeElement && document.activeElement !== document.body
					? document.activeElement
					: livePlayer;
				simulateSpacebarPress(focused);
				const videoEl = livePlayer.querySelector('video');
				if (videoEl && typeof videoEl.play === 'function') {
					videoEl.play().catch(() => {
						// ignore play promise rejection
					});
				}
				setStatusMessage('已尝试继续播放（聚焦+空格）');
				
				// 延迟检查播放是否成功
				setTimeout(() => {
					if (!isRunning) return;
					const currentPlayer = document.querySelector(SELECTORS.playerContainer);
					if (!currentPlayer) return;
					
					// 检查是否仍然暂停
					if (currentPlayer.classList.contains('plyr--paused')) {
						// 继续播放失败，记录失败
						markOperationResult('autoResume', false, '自动续播操作未能恢复播放');
					} else {
						// 成功恢复播放，重置计数器和状态
						pauseResumeAttempts = 0;
						pauseResumeBlocked = false;
						markOperationResult('autoResume', true);
						setStatusMessage('播放已恢复');
					}
				}, 1500);

				setTimeout(() => {
					if (livePlayer && livePlayer.dataset) {
						delete livePlayer.dataset.dqppResumeHandled;
					}
				}, 2000);
			}, delay);

			return true;
		}

		function maybeScheduleNextVideo() {
			if (!settings.autoPlayNext || nextClickScheduled) return false;
			if (!readyToAdvance) return false;
			const target = getNextVideoUrl();
			if (!target) {
				setStatusMessage('全部视频已播放完毕');
				readyToAdvance = false;
				return false;
			}
			scheduleNextVideoNavigation(target);
			return true;
		}

		function scheduleNextVideoNavigation(target) {
			const { url, label } = target;
		const delay = randomDelayMs();
		setStatusMessage(`将在 ${(delay / 1000).toFixed(1)}s 后跳转：${label}`);

		nextClickScheduled = true;
		readyToAdvance = false;

			setTimeout(() => {
				if (!isRunning || !settings.autoPlayNext) {
					nextClickScheduled = false;
					return;
				}
				setStatusMessage(`正在跳转：${label}`);
				window.location.href = url;
				nextClickScheduled = false;
		}, delay);
		}

		function classifyPlaybackModal(modal) {
			const message = getNormalizedText(modal.querySelector('.public_text > p:nth-child(2)'));
			const finishedKey = '当前视频播放完毕';
			const introKey = '您需要完整观看一遍课程视频，才能获取本课学时，看到视频播放完毕提示框即为完成，然后视频可以拖动播放。';

			if (modal.querySelector(SELECTORS.progressCancel)) {
				return 'progress';
			}

			const remainingSeconds = parseDurationToSeconds(getNormalizedText(document.querySelector(SELECTORS.playerRemaining)));
			if (message.includes(finishedKey) && (remainingSeconds === 0 || remainingSeconds === null)) {
				return 'finished';
			}

			if (message.includes(introKey)) {
				const elapsedSeconds = parseDurationToSeconds(getNormalizedText(document.querySelector(SELECTORS.playerElapsed)));
				const playlistSeconds = parseDurationToSeconds(getNormalizedText(document.querySelector(SELECTORS.playlistDuration)));
				if (elapsedSeconds !== null && playlistSeconds !== null && Math.abs(elapsedSeconds - playlistSeconds) <= 1) {
					return 'intro';
				}
			}

			return 'paused';
		}

		function getNextVideoUrl() {
			try {
				const currentUrl = new URL(window.location.href);
				const ridRaw = currentUrl.searchParams.get('r_id');
				if (!ridRaw) {
					console.warn('[DQPP] 当前链接缺少 r_id 参数，无法计算下一节');
					return null;
				}
				const rid = Number.parseInt(ridRaw, 10);
				if (!Number.isFinite(rid)) {
					console.warn('[DQPP] r_id 参数不是数字，无法计算下一节');
					return null;
				}
				const nextRid = rid + 1;
				currentUrl.searchParams.set('r_id', String(nextRid));
				return {
					url: currentUrl.toString(),
					label: `r_id=${nextRid}`,
				};
			} catch (error) {
				console.error('[DQPP] 生成下一节链接时出错:', error);
				return null;
			}
		}

		function getNormalizedText(element) {
			if (!element) return '';
			return (element.textContent || element.innerText || '').replace(/\s+/g, ' ').trim();
		}

		function parseDurationToSeconds(text) {
			if (!text) return null;
			const cleaned = text.replace(/[^0-9:]/g, '');
			if (!cleaned) return null;
			const parts = cleaned.split(':').map((part) => part.trim()).filter(Boolean);
			if (!parts.length) return null;
			let seconds = 0;
			let multiplier = 1;
			for (let i = parts.length - 1; i >= 0; i -= 1) {
				const value = Number.parseInt(parts[i], 10);
				if (Number.isNaN(value)) return null;
				seconds += value * multiplier;
				multiplier *= 60;
			}
			return seconds;
		}

	function clampDelayValue(value) {
		if (Number.isNaN(value) || value < 0) return 0;
		return Math.round(value * 10) / 10;
	}

	function ensureDelayOrder() {
		let { delayMin, delayMax } = settings;
		delayMin = clampDelayValue(parseFloat(delayMin));
		delayMax = clampDelayValue(parseFloat(delayMax));

		if (delayMax < delayMin) {
			[delayMin, delayMax] = [delayMax, delayMin];
		}

		if (delayMin === delayMax) {
			delayMax = clampDelayValue(delayMin + 0.1);
		}

		settings.delayMin = delayMin;
		settings.delayMax = delayMax;

		if (uiState.delayMinInput) uiState.delayMinInput.value = delayMin;
		if (uiState.delayMaxInput) uiState.delayMaxInput.value = delayMax;
	}

	function randomDelayMs() {
		ensureDelayOrder();
		const min = Math.max(0, Number(settings.delayMin) || 0);
		const max = Math.max(min, Number(settings.delayMax) || min + 0.1);
		const randomSeconds = Math.random() * (max - min) + min;
		return Math.round(randomSeconds * 1000);
	}

			function isElementVisible(element) {
				if (!element) return false;
				const rect = element.getBoundingClientRect();
				const style = window.getComputedStyle(element);
				if (style.display === 'none' || style.visibility === 'hidden' || style.opacity === '0') {
					return false;
				}
				return rect.width > 0 && rect.height > 0;
		}

	function safeClick(element) {
		if (!element) return false;
		const eventOptions = { bubbles: true, cancelable: true, view: window };

		try {
			element.dispatchEvent(new MouseEvent('mouseover', eventOptions));
			element.dispatchEvent(new MouseEvent('mousedown', eventOptions));
			element.dispatchEvent(new MouseEvent('mouseup', eventOptions));
			element.dispatchEvent(new MouseEvent('click', eventOptions));
			if (typeof element.click === 'function') {
				element.click();
			}
			return true;
		} catch (error) {
			console.error('[DQPP] 触发点击时出错:', error);
			return false;
		}
	}

	function simulateSpacebarPress(target) {
		const defaultTarget = document.body || window;
		const eventTarget = target || defaultTarget;
		const eventOptions = {
			key: ' ',
			code: 'Space',
			keyCode: 32,
			which: 32,
			bubbles: true,
			cancelable: true,
		};

		try {
			eventTarget.dispatchEvent(new KeyboardEvent('keydown', eventOptions));
			eventTarget.dispatchEvent(new KeyboardEvent('keypress', eventOptions));
			eventTarget.dispatchEvent(new KeyboardEvent('keyup', eventOptions));
		} catch (error) {
			console.error('[DQPP] 触发空格键时出错:', error);
		}
	}

	function logSettingChange(key) {
		switch (key) {
			case 'autoPlayNext':
				appendLog(`结束后自动播放：${settings.autoPlayNext ? '开启' : '关闭'}`, 'config');
				break;
			case 'skipIntro':
				appendLog(`跳过片头提示：${settings.skipIntro ? '开启' : '关闭'}`, 'config');
				break;
			case 'delayMin':
			case 'delayMax':
				appendLog(
					`随机延迟范围：${Number(settings.delayMin).toFixed(1)} ~ ${Number(settings.delayMax).toFixed(1)} 秒`,
					'config',
				);
				break;
			default:
				break;
		}
	}

	function loadSettings() {
		try {
			const raw = getCookieValue(COOKIE_NAME);
			if (!raw) return { ...defaultSettings };
			const parsed = JSON.parse(decodeURIComponent(raw));
			return { ...defaultSettings, ...parsed };
		} catch (error) {
			console.warn('[DQPP] 读取设置失败，使用默认值', error);
			return { ...defaultSettings };
		}
	}

	function saveSettings() {
		const serialisable = {
			...settings,
			panelPosition: {
				top: settings.panelPosition.top,
				left: settings.panelPosition.left,
			},
		};
		setCookie(COOKIE_NAME, JSON.stringify(serialisable), COOKIE_MAX_AGE);
	}

	function savePanelPosition() {
		if (!uiState.panel) return;
		settings.panelPosition = {
			top: uiState.panel.style.top || `${uiState.panel.offsetTop}px`,
			left: uiState.panel.style.left || `${uiState.panel.offsetLeft}px`,
		};
		saveSettings();
	}

	function setCookie(name, value, maxAgeSeconds) {
		if (!name) return;
		const encoded = encodeURIComponent(value);
		const cookie = `${name}=${encoded}; max-age=${maxAgeSeconds}; path=/; SameSite=Lax`;
		document.cookie = cookie;
	}

	function getCookieValue(name) {
		if (!name) return null;
		const cookies = document.cookie ? document.cookie.split('; ') : [];
		for (const chunk of cookies) {
			const [key, ...rest] = chunk.split('=');
			if (key === name) {
				return rest.join('=');
			}
		}
		return null;
	}

	function focusPlayerArea() {
		const centerX = Math.round(window.innerWidth / 2);
		const centerY = Math.round(window.innerHeight / 2);
		
		// 直接在页面中心点创建点击事件，不依赖特定元素
		const eventOptions = { 
			bubbles: true, 
			cancelable: true, 
			view: window,
			clientX: centerX,
			clientY: centerY,
			screenX: centerX,
			screenY: centerY
		};

		try {
			// 在页面中心点触发点击事件
			document.elementFromPoint(centerX, centerY)?.focus?.();
			document.dispatchEvent(new MouseEvent('click', eventOptions));
			
			// 确保页面获得焦点
			if (document.body) {
				document.body.focus();
			}
			window.focus();
		} catch (error) {
			console.warn('[DQPP] 聚焦页面中心时出错:', error);
			// 降级方案：尝试点击播放器容器
			const fallbackTarget = document.querySelector(SELECTORS.playerContainer) || document.body;
			safeClick(fallbackTarget);
		}
	}

	function prepareAlertAudio() {
		if (alertAudio) return alertAudio;
		if (!ALERT_AUDIO_URL) {
			console.warn('[DQPP] 音频URL未配置');
			return null;
		}
		
		try {
			alertAudio = new Audio(ALERT_AUDIO_URL);
			alertAudio.preload = 'auto';
			alertAudio.volume = 0.7;
			
			// 添加事件监听器来调试音频加载状态
			alertAudio.addEventListener('canplaythrough', () => {
				console.log('[DQPP] 提示音加载完成');
			});
			
			alertAudio.addEventListener('error', (e) => {
				console.error('[DQPP] 提示音加载失败:', e);
				alertAudio = null;
			});
			
			console.log('[DQPP] 提示音初始化完成，URL:', ALERT_AUDIO_URL);
			return alertAudio;
		} catch (error) {
			console.warn('[DQPP] 初始化提示音失败:', error);
			alertAudio = null;
			return null;
		}
	}

	function playAlertSound(contextMessage) {
		const audio = prepareAlertAudio();
		if (!audio) {
			console.warn('[DQPP] 无法获取音频实例');
			appendLog(`提示音播放失败：音频未初始化`, 'warn');
			return;
		}
		
		try {
			audio.currentTime = 0;
			const playPromise = audio.play();
			
			if (playPromise && typeof playPromise.catch === 'function') {
				playPromise.then(() => {
					console.log('[DQPP] 提示音播放成功');
					if (contextMessage) {
						appendLog(`🔊 ${contextMessage}`, 'warn');
					}
				}).catch((error) => {
					console.warn('[DQPP] 播放提示音失败:', error);
					appendLog(`提示音播放失败：${error.message}`, 'warn');
				});
			} else {
				console.log('[DQPP] 提示音播放（同步模式）');
				if (contextMessage) {
					appendLog(`🔊 ${contextMessage}`, 'warn');
				}
			}
		} catch (error) {
			console.warn('[DQPP] 尝试播放提示音时出错:', error);
			appendLog(`提示音播放异常：${error.message}`, 'warn');
		}
	}

	function markOperationResult(operationKey, succeeded, alertMessage) {
		if (!operationKey) return;
		if (succeeded) {
			operationFailureCounter[operationKey] = 0;
			return;
		}
		const nextValue = (operationFailureCounter[operationKey] || 0) + 1;
		operationFailureCounter[operationKey] = nextValue;
		
		// 每次达到3次失败就播放提示音，但不重置计数器
		if (nextValue % 3 === 0) {
			playAlertSound(alertMessage || `操作 ${operationKey} 已连续失败 ${nextValue} 次`);
		}
	}
})();