// ==UserScript==
// @name         抖音视频下载助手
// @namespace    https://github.com/scriptCat/
// @version      1.0.0
// @description  抖音视频下载助手，监听视频详情API并提供下载功能
// @author       wangxi
// @match        https://www.douyin.com/*
// @grant        GM_addStyle
// @grant        GM_download
// @connect      douyin.com
// @connect      *
// @require      https://cdn.jsdelivr.net/npm/sweetalert2@11
// @run-at       document-start
// @license      MIT
// ==/UserScript==



(function() {
    'use strict';
    
    // 配置
    const CONFIG = {
        enabled: true
    };
    
    // 当前视频信息
    let currentVideoInfo = null;
    
    // 简化工具函数
    function showToast(message, type = 'info') {
        const Toast = Swal.mixin({
            toast: true,
            position: 'top-end',
            showConfirmButton: false,
            timer: 2000
        });
        Toast.fire({ icon: type, title: message });
    }
    

    
    // 下载视频
    function downloadVideo() {
        if (!currentVideoInfo) {
            showToast('没有可下载的视频', 'error');
            return;
        }
        
        const filename = `${currentVideoInfo.videoId}.mp4`;
        console.log('[抖音下载] 下载链接:', currentVideoInfo.downloadUrl);
        console.log('[抖音下载] 文件名:', filename);
        
        updateFloatingButton('downloading');
        
        // 使用fetch下载并创建blob链接
        fetch(currentVideoInfo.downloadUrl, {
            headers: {
                'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.124 Safari/537.36',
                'Referer': 'https://www.douyin.com/',
                'Accept': '*/*'
            }
        })
        .then(response => {
            if (!response.ok) {
                throw new Error(`HTTP error! status: ${response.status}`);
            }
            return response.blob();
        })
        .then(blob => {
            // 创建下载链接
            const url = URL.createObjectURL(blob);
            const a = document.createElement('a');
            a.href = url;
            a.download = filename;
            document.body.appendChild(a);
            a.click();
            document.body.removeChild(a);
            URL.revokeObjectURL(url);
            
            showToast('下载成功', 'success');
            updateFloatingButton('ready');
        })
        .catch(error => {
            console.error('[抖音下载] 下载失败:', error);
            showToast('下载失败', 'error');
            updateFloatingButton('ready');
        });
    }
    
         // 创建悬浮按钮
     function createFloatingButton() {
         // 检查是否已存在
         if (document.querySelector('.douyin-download-float')) {
             return;
         }
         
         const floatingButton = document.createElement('div');
        floatingButton.className = 'douyin-download-float';
        floatingButton.innerHTML = `
            <div class="douyin-download-btn" title="下载视频">
                <svg class="douyin-download-icon" viewBox="0 0 24 24" fill="currentColor">
                    <path d="M19 9h-4V3H9v6H5l7 7 7-7zM5 18v2h14v-2H5z"/>
                </svg>
                <span class="douyin-download-text">下载</span>
            </div>
        `;
        
        // 添加样式
        GM_addStyle(`
            .douyin-download-float {
                position: fixed;
                bottom: 100px;
                right: 30px;
                z-index: 9999;
                user-select: none;
                transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
                opacity: 0.8;
            }
            
            .douyin-download-float:hover {
                opacity: 1;
                transform: scale(1.05);
            }
            
            .douyin-download-float.dragging {
                transition: none !important;
                opacity: 1;
                transform: scale(1.05);
            }
            
            .douyin-download-btn {
                display: flex;
                align-items: center;
                gap: 8px;
                padding: 12px 16px;
                background: linear-gradient(135deg, #ff6b6b 0%, #ff8e8e 100%);
                color: white;
                border-radius: 25px;
                cursor: pointer;
                font-size: 14px;
                font-weight: 500;
                box-shadow: 0 4px 12px rgba(255, 107, 107, 0.3);
                transition: all 0.2s ease;
                min-width: 80px;
                justify-content: center;
            }
            
            .douyin-download-btn:hover {
                background: linear-gradient(135deg, #ff5252 0%, #ff7979 100%);
                box-shadow: 0 6px 16px rgba(255, 107, 107, 0.4);
            }
            
            .douyin-download-btn:active {
                transform: scale(0.95);
            }
            
            .douyin-download-btn.disabled {
                background: linear-gradient(135deg, #d1d5db 0%, #9ca3af 100%);
                cursor: not-allowed;
                opacity: 0.6;
            }
            
            .douyin-download-btn.downloading {
                background: linear-gradient(135deg, #f59e0b 0%, #fbbf24 100%);
                box-shadow: 0 4px 12px rgba(245, 158, 11, 0.3);
            }
            
            .douyin-download-icon {
                width: 16px;
                height: 16px;
                flex-shrink: 0;
            }
            
            .douyin-download-icon.spinning {
                animation: spin 1s linear infinite;
            }
            
            @keyframes spin {
                from { transform: rotate(0deg); }
                to { transform: rotate(360deg); }
            }
            
            .douyin-download-text {
                font-size: 13px;
                font-weight: 600;
            }
            
            /* 吸附效果 */
            .douyin-download-float.snap-right {
                right: 0;
                border-radius: 25px 0 0 25px;
            }
            
            .douyin-download-float.snap-left {
                left: 0;
                border-radius: 0 25px 25px 0;
            }
        `);
        
        // 添加到页面
        document.body.appendChild(floatingButton);
        
        // 设置拖拽功能
        setupDragAndSnap(floatingButton);
        
        // 设置点击事件
        const downloadBtn = floatingButton.querySelector('.douyin-download-btn');
        downloadBtn.addEventListener('click', () => {
            if (downloadBtn.classList.contains('disabled')) return;
            
            // 点击反馈
            downloadBtn.style.transform = 'scale(0.9)';
            setTimeout(() => {
                downloadBtn.style.transform = '';
            }, 150);
            
            downloadVideo();
        });
        

    }
    
    // 设置拖拽和吸附功能
    function setupDragAndSnap(floatingButton) {
        let isDragging = false;
        let startX, startY, startLeft, startTop;
        
        floatingButton.addEventListener('mousedown', (e) => {
            isDragging = true;
            startX = e.clientX;
            startY = e.clientY;
            
            const rect = floatingButton.getBoundingClientRect();
            startLeft = rect.left;
            startTop = rect.top;
            
            floatingButton.classList.add('dragging');
            e.preventDefault();
        });
        
        document.addEventListener('mousemove', (e) => {
            if (!isDragging) return;
            
            const deltaX = e.clientX - startX;
            const deltaY = e.clientY - startY;
            
            let newLeft = startLeft + deltaX;
            let newTop = startTop + deltaY;
            
            // 限制在视窗内
            const maxX = window.innerWidth - floatingButton.offsetWidth;
            const maxY = window.innerHeight - floatingButton.offsetHeight;
            
            newLeft = Math.max(0, Math.min(newLeft, maxX));
            newTop = Math.max(0, Math.min(newTop, maxY));
            
            // 设置位置
            floatingButton.style.left = newLeft + 'px';
            floatingButton.style.top = newTop + 'px';
            floatingButton.style.right = 'auto';
            floatingButton.style.bottom = 'auto';
        });
        
        document.addEventListener('mouseup', () => {
            if (!isDragging) return;
            
            isDragging = false;
            floatingButton.classList.remove('dragging');
            
            // 吸附效果
            const rect = floatingButton.getBoundingClientRect();
            const windowWidth = window.innerWidth;
            const centerX = rect.left + rect.width / 2;
            
            // 移除吸附类
            floatingButton.classList.remove('snap-left', 'snap-right');
            
            if (centerX < windowWidth / 2) {
                // 吸附到左边
                floatingButton.style.left = '0px';
                floatingButton.style.right = 'auto';
                floatingButton.classList.add('snap-left');
            } else {
                // 吸附到右边
                floatingButton.style.right = '0px';
                floatingButton.style.left = 'auto';
                floatingButton.classList.add('snap-right');
            }
        });
    }
    
    // 更新悬浮按钮状态
    function updateFloatingButton(status = 'ready') {
        const floatingButton = document.querySelector('.douyin-download-float');
        if (!floatingButton) return;
        
        const downloadBtn = floatingButton.querySelector('.douyin-download-btn');
        const icon = floatingButton.querySelector('.douyin-download-icon');
        const text = floatingButton.querySelector('.douyin-download-text');
        
        if (!downloadBtn || !icon || !text) return;
        
        // 移除所有状态类
        downloadBtn.classList.remove('disabled', 'downloading');
        icon.classList.remove('spinning');
        
        switch (status) {
            case 'ready':
                if (currentVideoInfo) {
                    downloadBtn.title = `下载视频: ${currentVideoInfo.title}`;
                    text.textContent = '下载';
                    icon.innerHTML = '<path d="M19 9h-4V3H9v6H5l7 7 7-7zM5 18v2h14v-2H5z"/>';
                } else {
                    downloadBtn.classList.add('disabled');
                    downloadBtn.title = '等待视频加载...';
                    text.textContent = '等待';
                    icon.innerHTML = '<path d="M12 2C6.48 2 2 6.48 2 12s4.48 10 10 10 10-4.48 10-10S17.52 2 12 2zm-2 15l-5-5 1.41-1.41L10 14.17l7.59-7.59L19 8l-9 9z"/>';
                }
                break;
                
            case 'downloading':
                downloadBtn.classList.add('downloading');
                downloadBtn.title = '正在下载...';
                text.textContent = '下载中';
                icon.classList.add('spinning');
                icon.innerHTML = '<path d="M12 2C6.48 2 2 6.48 2 12s4.48 10 10 10 10-4.48 10-10S17.52 2 12 2zm-2 15l-5-5 1.41-1.41L10 14.17l7.59-7.59L19 8l-9 9z"/>';
                break;
        }
    }
    
      // 早期初始化
     function earlyInit() {
         // 简化的早期初始化
     }
     
     // 从页面提取视频信息
     function extractVideoInfoFromPage() {
         // 直接从HTML video/source标签提取
         extractFromVideoTags();
     }
     

     
     // 从HTML video/source标签提取下载链接
     function extractFromVideoTags() {
         // 直接使用完整选择器获取第一个source
         const firstSource = document.querySelector("xg-video-container video source:first-child");
         
         if (firstSource) {
             const src = firstSource.src || firstSource.getAttribute('src');
             
             if (src) {
                 const videoId = extractVideoIdFromPage();
                 
                 currentVideoInfo = {
                     videoId: videoId || 'unknown',
                     vid: 'vid',
                     downloadUrl: src,
                     title: '抖音视频'
                 };
                 
                 updateFloatingButton();
             }
         }
     }
     
     // 从页面提取视频ID
     function extractVideoIdFromPage() {
         // 方法1：从URL提取
         const urlMatch = window.location.href.match(/\/video\/(\d+)/);
         if (urlMatch) return urlMatch[1];
         
         // 方法2：从指定CSS选择器的链接提取
         const linkElement = document.querySelector('#user_detail_element > div > div._1PChJilq > div > div > div._akC5KCF.W6aLyAOC > div > div.UTSD8keU.bVgnIvTC > ul > li:nth-child(4) > div > a');
         if (linkElement && linkElement.href) {
             const linkMatch = linkElement.href.match(/\/video\/(\d+)/);
             if (linkMatch) return linkMatch[1];
         }
         
         return null;
     }
     
     // 界面初始化
     function uiInit() {
         // 创建悬浮按钮
         createFloatingButton();
         
         // 提取视频信息（带重试机制）
         function tryExtractVideo(retries = 5) {
             extractVideoInfoFromPage();
             if (!currentVideoInfo && retries > 0) {
                 setTimeout(() => tryExtractVideo(retries - 1), 1000);
             }
         }
         tryExtractVideo();
         
         // 监听页面变化
         let currentUrl = location.href;
         new MutationObserver(() => {
             // 检查URL变化
             if (location.href !== currentUrl) {
                 currentUrl = location.href;
                 currentVideoInfo = null;
                 updateFloatingButton();
                 setTimeout(() => tryExtractVideo(3), 500);
             }
             
             // 检查新video标签
             if (!currentVideoInfo) {
                 setTimeout(extractFromVideoTags, 500);
             }
         }).observe(document, {
             subtree: true,
             childList: true
         });
     }
     
     // 立即执行早期初始化
     earlyInit();
     
     // 等待页面准备好后初始化界面
     if (document.readyState === 'loading') {
         document.addEventListener('DOMContentLoaded', () => {
             setTimeout(uiInit, 500);
         });
     } else {
         setTimeout(uiInit, 500);
     }
})();