// ========== 初始化二维码 ==========
document.addEventListener('DOMContentLoaded', function () {
    new QRCode(document.getElementById('qrcode'), {
        text: SERVER_URL,
        width: 140,
        height: 140,
        colorDark: '#333333',
        colorLight: '#ffffff',
        correctLevel: QRCode.CorrectLevel.M
    });
    loadFiles();
});

// ========== 复制链接 ==========
function copyUrl() {
    const url = document.getElementById('urlValue').textContent;
    navigator.clipboard.writeText(url).then(() => {
        const btn = document.querySelector('.btn-copy');
        const original = btn.textContent;
        btn.textContent = '已复制 ✓';
        setTimeout(() => btn.textContent = original, 1500);
    }).catch(() => {
        // 兼容旧浏览器
        const input = document.createElement('input');
        input.value = url;
        document.body.appendChild(input);
        input.select();
        document.execCommand('copy');
        document.body.removeChild(input);
    });
}

// ========== 上传相关 ==========
const dropZone = document.getElementById('dropZone');
const fileInput = document.getElementById('fileInput');
const progressContainer = document.getElementById('progressContainer');
const progressFill = document.getElementById('progressFill');
const progressName = document.getElementById('progressName');
const progressPercent = document.getElementById('progressPercent');

// 点击触发文件选择
dropZone.addEventListener('click', () => fileInput.click());

// 文件选择
fileInput.addEventListener('change', (e) => {
    if (e.target.files.length) {
        uploadFiles(Array.from(e.target.files));
        fileInput.value = '';
    }
});

// 拖拽事件
['dragenter', 'dragover'].forEach(evt => {
    dropZone.addEventListener(evt, (e) => {
        e.preventDefault();
        e.stopPropagation();
        dropZone.classList.add('dragover');
    });
});

['dragleave', 'drop'].forEach(evt => {
    dropZone.addEventListener(evt, (e) => {
        e.preventDefault();
        e.stopPropagation();
        dropZone.classList.remove('dragover');
    });
});

dropZone.addEventListener('drop', (e) => {
    const files = Array.from(e.dataTransfer.files);
    if (files.length) uploadFiles(files);
});

// 批量上传
function uploadFiles(files) {
    let index = 0;
    const total = files.length;

    function next() {
        if (index >= total) {
            progressContainer.style.display = 'none';
            loadFiles();
            return;
        }
        const file = files[index];
        index++;
        uploadSingle(file, () => next());
    }
    next();
}

// 单个文件上传
function uploadSingle(file, callback) {
    const formData = new FormData();
    formData.append('file', file);

    const xhr = new XMLHttpRequest();

    progressContainer.style.display = 'block';
    progressName.textContent = file.name;
    progressFill.style.width = '0%';
    progressPercent.textContent = '0%';

    xhr.upload.addEventListener('progress', (e) => {
        if (e.lengthComputable) {
            const percent = Math.round((e.loaded / e.total) * 100);
            progressFill.style.width = percent + '%';
            progressPercent.textContent = percent + '%';
        }
    });

    xhr.addEventListener('load', () => {
        progressFill.style.width = '100%';
        progressPercent.textContent = '100%';
        setTimeout(callback, 300);
    });

    xhr.addEventListener('error', () => {
        alert('上传失败：' + file.name);
        callback();
    });

    xhr.open('POST', '/upload');
    xhr.send(formData);
}

// ========== 文件列表 ==========
function loadFiles() {
    fetch('/files')
        .then(res => res.json())
        .then(files => renderFiles(files))
        .catch(err => console.error('加载文件失败', err));
}

function renderFiles(files) {
    const list = document.getElementById('fileList');
    if (!files.length) {
        list.innerHTML = '<li class="empty">暂无文件</li>';
        return;
    }
    list.innerHTML = files.map(f => `
        <li>
            <div class="file-info">
                <span class="file-icon">${getIcon(f.name)}</span>
                <div class="file-meta">
                    <div class="file-name" title="${escapeHtml(f.name)}">${escapeHtml(f.name)}</div>
                    <div class="file-size">${f.size}</div>
                </div>
            </div>
            <div class="file-actions">
                <a class="btn-download" href="/download/${encodeURIComponent(f.name)}">下载</a>
                <button class="btn-delete" onclick="deleteFile('${escapeJs(f.name)}')">删除</button>
            </div>
        </li>
    `).join('');
}

function deleteFile(name) {
    if (!confirm('确定删除 ' + name + ' ？')) return;
    fetch('/delete/' + encodeURIComponent(name), { method: 'DELETE' })
        .then(res => res.json())
        .then(() => loadFiles())
        .catch(err => alert('删除失败'));
}

// ========== 工具函数 ==========
function getIcon(name) {
    const ext = name.split('.').pop().toLowerCase();
    const map = {
        jpg: '🖼️', jpeg: '🖼️', png: '🖼️', gif: '🖼️', webp: '🖼️', svg: '🖼️',
        mp4: '🎬', mov: '🎬', avi: '🎬', mkv: '🎬',
        mp3: '🎵', wav: '🎵', flac: '🎵',
        pdf: '📕', doc: '📘', docx: '📘', xls: '📗', xlsx: '📗', ppt: '📙', pptx: '📙',
        zip: '🗜️', rar: '🗜️', '7z': '🗜️', tar: '🗜️', gz: '🗜️',
        txt: '📄', md: '📝', json: '📋', xml: '📋',
        exe: '⚙️', apk: '📱', dmg: '💿', iso: '💿'
    };
    return map[ext] || '📄';
}

function escapeHtml(str) {
    return String(str).replace(/[&<>"']/g, s => ({
        '&': '&amp;', '<': '&lt;', '>': '&gt;', '"': '&quot;', "'": '&#39;'
    }[s]));
}

function escapeJs(str) {
    return String(str).replace(/\\/g, '\\\\').replace(/'/g, "\\'").replace(/"/g, '\\"');
}