// ==UserScript==
// @name         rm在线观看加密TXT文件
// @namespace     http://tampermonkey.net/
// @version      1.2
// @description  在下载确认页面添加在线观看按钮，直接解密并显示TXT内容
// @author       YourName
// @match        *://*/*
// @grant        GM_xmlhttpRequest
// ==/UserScript==

(function() {
    'use strict';

    // ==================== 脚本启用提示 ====================
    console.log('%c🎬 在线观看加密TXT文件脚本已启用', 'color: #00ff00; font-size: 16px; font-weight: bold;');

    // 页面角标提示
    function addPageIndicator() {
        const indicator = document.createElement('div');
        indicator.id = 'crypto-script-indicator';
        indicator.innerHTML = '🎬 加密TXT在线观看脚本已启动';
        indicator.style.cssText = `
            position: fixed;
            bottom: 20px;
            right: 20px;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            color: white;
            padding: 6px 12px;
            border-radius: 16px;
            font-size: 11px;
            font-family: Arial, sans-serif;
            z-index: 999999;
            box-shadow: 0 2px 8px rgba(0,0,0,0.2);
            cursor: pointer;
            opacity: 0.85;
        `;
        indicator.onclick = () => indicator.remove();
        document.body.appendChild(indicator);
        setTimeout(() => indicator.remove(), 5000);
    }

    if (document.readyState === 'loading') {
        document.addEventListener('DOMContentLoaded', addPageIndicator);
    } else {
        addPageIndicator();
    }

    // ==================== 核心加密解密模块 ====================
    const FIXED_KEY = "multi-mode-encryption-2024";

    function base64ToArray(base64) {
        const binaryString = atob(base64);
        const len = binaryString.length;
        const bytes = new Uint8Array(len);
        for (let i = 0; i < len; i++) {
            bytes[i] = binaryString.charCodeAt(i);
        }
        return bytes;
    }

    function isEncryptedText(text) {
        if (!text || text.length < 50) return false;
        try {
            const base64Regex = /^[A-Za-z0-9+/]*={0,2}$/;
            const cleanText = text.replace(/\s/g, '');
            const isBase64 = base64Regex.test(cleanText);
            const hasInvalidChars = /[^A-Za-z0-9+/=\s]/.test(text);
            const lengthValid = cleanText.length % 4 === 0;
            const hasChineseChars = /[\u4e00-\u9fa5]/.test(text);
            return isBase64 && !hasInvalidChars && lengthValid && !hasChineseChars;
        } catch {
            return false;
        }
    }

    async function decrypt(encryptedBase64, password = FIXED_KEY) {
        try {
            const cleanBase64 = encryptedBase64.replace(/\s/g, '');
            const combined = base64ToArray(cleanBase64);
            const salt = combined.slice(0, 16);
            const iv = combined.slice(16, 28);
            const encrypted = combined.slice(28);

            const encoder = new TextEncoder();
            const passwordKey = await crypto.subtle.importKey(
                'raw',
                encoder.encode(password),
                { name: 'PBKDF2' },
                false,
                ['deriveKey']
            );

            const key = await crypto.subtle.deriveKey(
                {
                    name: 'PBKDF2',
                    salt: salt,
                    iterations: 100000,
                    hash: 'SHA-256'
                },
                passwordKey,
                { name: 'AES-GCM', length: 256 },
                false,
                ['decrypt']
            );

            const decrypted = await crypto.subtle.decrypt(
                { name: 'AES-GCM', iv: iv },
                key,
                encrypted
            );

            return new TextDecoder().decode(decrypted);
        } catch (error) {
            console.error('解密错误:', error);
            throw new Error('解密失败：文件可能已损坏或不是有效的加密文件');
        }
    }

    // ==================== 获取下载URL ====================
    function getDownloadUrl() {
        const confirmBtn = document.querySelector('.btn2 button[onclick*="location.href"], button[onclick*="location.href"]');
        if (confirmBtn) {
            const onclickAttr = confirmBtn.getAttribute('onclick');
            const match = onclickAttr.match(/location\.href='([^']+)'/);
            if (match && match[1]) {
                return match[1];
            }
        }
        return null;
    }

    // ==================== 获取并显示文件内容 ====================
    async function fetchAndDisplayFile() {
        const downloadUrl = getDownloadUrl();

        if (!downloadUrl) {
            showError('无法获取下载链接');
            return;
        }

        showFullscreenView('loading', '正在获取文件内容，请稍候...');

        try {
            GM_xmlhttpRequest({
                method: 'GET',
                url: downloadUrl,
                responseType: 'text',
                onload: async function(response) {
                    if (response.status === 200) {
                        const content = response.responseText;

                        const contentType = response.responseHeaders?.toLowerCase() || '';
                        const isTextFile = contentType.includes('text/plain') ||
                                          downloadUrl.toLowerCase().endsWith('.txt') ||
                                          !content.match(/[\x00-\x08\x0b\x0c\x0e-\x1f]/);

                        if (!isTextFile) {
                            showError('该文件不是文本文件（.txt），无法在线观看');
                            return;
                        }

                        if (!isEncryptedText(content)) {
                            showFullscreenView('text', content, '⚠️ 该文件不是加密内容，以下是原始内容：');
                            return;
                        }

                        updateFullscreenProgress('正在解密内容，请稍候...');

                        try {
                            const decrypted = await decrypt(content);
                            showFullscreenView('text', decrypted, '✅ 解密成功！以下是文件内容：');
                        } catch (decryptError) {
                            showError(`解密失败：${decryptError.message}`);
                        }

                    } else {
                        showError(`获取文件失败：HTTP ${response.status}`);
                    }
                },
                onerror: function(error) {
                    showError('网络请求失败，请检查网络连接');
                },
                ontimeout: function() {
                    showError('请求超时，请稍后重试');
                },
                timeout: 30000
            });

        } catch (error) {
            showError(`发生错误：${error.message}`);
        }
    }

    // ==================== 全屏显示界面 ====================
    function showFullscreenView(type, content, title = '') {
        const existingView = document.getElementById('onlineViewer');
        if (existingView) existingView.remove();

        const viewer = document.createElement('div');
        viewer.id = 'onlineViewer';
        viewer.style.cssText = `
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background: rgba(0,0,0,0.95);
            z-index: 999999;
            display: flex;
            flex-direction: column;
            font-family: 'Microsoft YaHei', 'SimHei', 'PingFang SC', monospace;
        `;

        const header = document.createElement('div');
        header.style.cssText = `
            background: #2d2d2d;
            color: white;
            padding: 15px 20px;
            display: flex;
            justify-content: space-between;
            align-items: center;
            border-bottom: 1px solid #444;
            flex-shrink: 0;
        `;

        const titleSpan = document.createElement('span');
        titleSpan.style.cssText = `
            font-size: 18px;
            font-weight: bold;
        `;
        titleSpan.textContent = title || (type === 'loading' ? '加载中' : '在线观看');

        const closeBtn = document.createElement('button');
        closeBtn.textContent = '✕ 关闭';
        closeBtn.style.cssText = `
            background: #e74c3c;
            color: white;
            border: none;
            padding: 8px 20px;
            border-radius: 5px;
            cursor: pointer;
            font-size: 14px;
            font-weight: bold;
        `;
        closeBtn.onmouseover = () => closeBtn.style.background = '#c0392b';
        closeBtn.onmouseout = () => closeBtn.style.background = '#e74c3c';
        closeBtn.onclick = () => viewer.remove();

        header.appendChild(titleSpan);
        header.appendChild(closeBtn);

        const contentArea = document.createElement('div');
        contentArea.className = 'content-area';
        contentArea.style.cssText = `
            flex: 1;
            overflow: auto;
            padding: 20px;
            background: #1e1e1e;
        `;

        if (type === 'loading') {
            contentArea.innerHTML = `
                <div style="display: flex; justify-content: center; align-items: center; height: 100%;">
                    <div style="text-align: center;">
                        <div style="width: 50px; height: 50px; border: 4px solid #3330; border-top-color: #3498db; border-radius: 50%; animation: spin 1s linear infinite; margin: 0 auto 20px;"></div>
                        <div style="color: #ccc; font-size: 16px;">${content}</div>
                    </div>
                </div>
                <style>
                    @keyframes spin {
                        to { transform: rotate(360deg); }
                    }
                </style>
            `;
        } else if (type === 'text') {
            const pre = document.createElement('pre');
            pre.textContent = content;
            pre.style.cssText = `
                margin: 0;
                padding: 15px;
                background: #252526;
                color: #d4d4d4;
                border-radius: 8px;
                font-family: 'Consolas', 'Monaco', 'Courier New', monospace;
                font-size: 14px;
                line-height: 1.6;
                overflow-x: auto;
                white-space: pre-wrap;
                word-wrap: break-word;
            `;
            contentArea.appendChild(pre);

            const actions = document.createElement('div');
            actions.style.cssText = `
                margin-top: 15px;
                display: flex;
                gap: 10px;
                justify-content: flex-end;
            `;

            const copyBtn = createActionButton('📋 复制全部内容', async () => {
                try {
                    await navigator.clipboard.writeText(content);
                    showToast('已复制到剪贴板');
                } catch (err) {
                    showToast('复制失败');
                }
            });

            const downloadBtn = createActionButton('💾 下载为TXT', () => {
                const blob = new Blob([content], { type: 'text/plain;charset=utf-8' });
                const url = URL.createObjectURL(blob);
                const a = document.createElement('a');
                a.href = url;
                a.download = `decrypted_${Date.now()}.txt`;
                a.click();
                URL.revokeObjectURL(url);
                showToast('开始下载');
            });

            actions.appendChild(copyBtn);
            actions.appendChild(downloadBtn);
            contentArea.appendChild(actions);
        }

        viewer.appendChild(header);
        viewer.appendChild(contentArea);
        document.body.appendChild(viewer);
    }

    function updateFullscreenProgress(message) {
        const contentArea = document.querySelector('#onlineViewer .content-area');
        if (contentArea) {
            contentArea.innerHTML = `
                <div style="display: flex; justify-content: center; align-items: center; height: 100%;">
                    <div style="text-align: center;">
                        <div style="width: 40px; height: 40px; border: 3px solid #333; border-top-color: #3498db; border-radius: 50%; animation: spin 1s linear infinite; margin: 0 auto 15px;"></div>
                        <div style="color: #ccc;">${message}</div>
                    </div>
                </div>
            `;
        }
    }

    function createActionButton(text, onClick) {
        const btn = document.createElement('button');
        btn.textContent = text;
        btn.style.cssText = `
            background: #3498db;
            color: white;
            border: none;
            padding: 8px 16px;
            border-radius: 5px;
            cursor: pointer;
            font-size: 14px;
        `;
        btn.onmouseover = () => btn.style.background = '#2980b9';
        btn.onmouseout = () => btn.style.background = '#3498db';
        btn.onclick = onClick;
        return btn;
    }

    function showError(message) {
        const existingView = document.getElementById('onlineViewer');
        if (existingView) existingView.remove();

        const toast = document.createElement('div');
        toast.textContent = `❌ ${message}`;
        toast.style.cssText = `
            position: fixed;
            bottom: 20px;
            left: 50%;
            transform: translateX(-50%);
            background: #e74c3c;
            color: white;
            padding: 12px 24px;
            border-radius: 8px;
            z-index: 1000000;
            font-size: 14px;
            box-shadow: 0 2px 10px rgba(0,0,0,0.2);
            animation: fadeOut 3s ease forwards;
        `;

        const style = document.createElement('style');
        style.textContent = `
            @keyframes fadeOut {
                0% { opacity: 1; }
                70% { opacity: 1; }
                100% { opacity: 0; visibility: hidden; }
            }
        `;
        document.head.appendChild(style);
        document.body.appendChild(toast);
        setTimeout(() => toast.remove(), 3000);
    }

    function showToast(message) {
        const toast = document.createElement('div');
        toast.textContent = `✅ ${message}`;
        toast.style.cssText = `
            position: fixed;
            bottom: 20px;
            right: 20px;
            background: #27ae60;
            color: white;
            padding: 10px 20px;
            border-radius: 5px;
            z-index: 1000000;
            font-size: 14px;
            animation: fadeOut 2s ease forwards;
        `;
        document.body.appendChild(toast);
        setTimeout(() => toast.remove(), 2000);
    }

    // ==================== 添加在线观看按钮（带边框样式）====================
    function addOnlineViewButton() {
        // 查找确定按钮
        let confirmBtn = document.querySelector('.btn2 button[onclick*="location.href"]');
        if (!confirmBtn) {
            confirmBtn = document.querySelector('button[onclick*="location.href"]');
        }
        if (!confirmBtn) {
            return;
        }

        if (document.getElementById('onlineViewBtn')) {
            return;
        }

        // 找到 popBottom 容器
        const popBottom = confirmBtn.closest('.popBottom');
        if (!popBottom) {
            return;
        }

        // 找到取消按钮所在的 span
        const cancelSpan = popBottom.querySelector('.bt2');

        // 创建新的 span 用于在线观看按钮
        const newSpan = document.createElement('span');
        newSpan.className = 'btn-online';
        newSpan.style.marginLeft = '15px';

        // 创建在线观看按钮 - 带边框样式
        const onlineBtn = document.createElement('button');
        onlineBtn.id = 'onlineViewBtn';
        onlineBtn.textContent = '🎬 在线观看';
        onlineBtn.type = 'button';

        // 漂亮的边框样式
        onlineBtn.style.cssText = `
            padding: 6px 16px;
            border: 1px solid #ff6600;
            border-radius: 20px;
            background: linear-gradient(135deg, #fff 0%, #fff5e6 100%);
            color: #ff6600;
            cursor: pointer;
            font-size: 14px;
            font-weight: bold;
            transition: all 0.3s ease;
            box-shadow: 0 1px 3px rgba(0,0,0,0.1);
        `;

        // 悬停效果
        onlineBtn.onmouseover = () => {
            onlineBtn.style.background = 'linear-gradient(135deg, #ff6600 0%, #ff8833 100%)';
            onlineBtn.style.color = '#fff';
            onlineBtn.style.borderColor = '#ff6600';
            onlineBtn.style.transform = 'translateY(-1px)';
            onlineBtn.style.boxShadow = '0 3px 8px rgba(255,102,0,0.3)';
        };
        onlineBtn.onmouseout = () => {
            onlineBtn.style.background = 'linear-gradient(135deg, #fff 0%, #fff5e6 100%)';
            onlineBtn.style.color = '#ff6600';
            onlineBtn.style.borderColor = '#ff6600';
            onlineBtn.style.transform = 'translateY(0)';
            onlineBtn.style.boxShadow = '0 1px 3px rgba(0,0,0,0.1)';
        };

        // 点击事件
        onlineBtn.onclick = (e) => {
            e.preventDefault();
            e.stopPropagation();
            fetchAndDisplayFile();
        };

        // 将按钮放入新span
        const innerSpan = document.createElement('span');
        innerSpan.appendChild(onlineBtn);
        newSpan.appendChild(innerSpan);

        // 插入到取消按钮之前
        if (cancelSpan) {
            popBottom.insertBefore(newSpan, cancelSpan);
        } else {
            popBottom.appendChild(newSpan);
        }

        // 给取消按钮也加点左边距
        if (cancelSpan && !cancelSpan.style.marginLeft) {
            cancelSpan.style.marginLeft = '15px';
        }

        console.log('✅ 在线观看按钮已添加，带边框样式');
    }

    // 监听页面变化，动态添加按钮
    function init() {
        addOnlineViewButton();

        const observer = new MutationObserver(function(mutations) {
            if (!document.getElementById('onlineViewBtn')) {
                addOnlineViewButton();
            }
        });
        observer.observe(document.body, { childList: true, subtree: true });
    }

    if (document.readyState === 'loading') {
        document.addEventListener('DOMContentLoaded', init);
    } else {
        init();
    }

})();