u

code/file-preview/g3-file/common.js

@@ -0,0 +1,239 @@
+var G3FileUtils = {
+  /**
+   * 格式化文件大小
+   * @param {number} bytes - 文件大小（字节）
+   * @returns {string} 格式化后的大小
+   */
+  formatFileSize: function (bytes) {
+    var numBytes = typeof bytes === "string" ? parseFloat(bytes) : bytes;
+    if (
+      numBytes === null ||
+      numBytes === undefined ||
+      isNaN(numBytes) ||
+      numBytes <= 0
+    ) {
+      return "-";
+    }
+
+    var k = 1024;
+    var sizes = ["B", "KB", "MB", "GB", "TB"];
+
+    var i = Math.floor(Math.log(numBytes) / Math.log(k));
+    i = Math.max(0, Math.min(i, sizes.length - 1));
+
+    return (numBytes / Math.pow(k, i)).toFixed(2) + " " + sizes[i];
+  },
+
+  /**
+   * 格式化日期
+   * @param {string} dateStr - 日期字符串
+   * @returns {string} 格式化后的日期
+   */
+  formatDate: function (dateStr) {
+    if (!dateStr) return "-";
+
+    var date = new Date(dateStr);
+
+    if (isNaN(date.getTime())) {
+      return "-";
+    }
+
+    var year = date.getFullYear();
+    var month = ("0" + (date.getMonth() + 1)).slice(-2);
+    var day = ("0" + date.getDate()).slice(-2);
+    var hours = ("0" + date.getHours()).slice(-2);
+    var minutes = ("0" + date.getMinutes()).slice(-2);
+    var seconds = ("0" + date.getSeconds()).slice(-2);
+
+    return (
+      year +
+      "-" +
+      month +
+      "-" +
+      day +
+      " " +
+      hours +
+      ":" +
+      minutes +
+      ":" +
+      seconds
+    );
+  },
+
+  /**
+   * 判断是否为图片文件
+   * @param {string} filename - 文件名
+   * @returns {boolean} 是否为图片文件
+   */
+  isImageFile: function (filename) {
+    if (!filename || typeof filename !== "string") return false;
+
+    const ext = filename.slice(filename.lastIndexOf(".") + 1).toLowerCase();
+    const imageExts = new Set(["jpg", "jpeg", "png", "gif", "bmp", "webp"]);
+
+    return imageExts.has(ext);
+  },
+
+  /**
+   * 获取文件图标
+   * @param {string} filename - 文件名
+   * @returns {string} 图标HTML
+   */
+  getFileIcon: function (filename) {
+    var ext = filename.split(".").pop().toLowerCase();
+
+    if (this.isImageFile(filename)) {
+      return "";
+    }
+
+    // 根据不同的文件类型显示不同的图标
+    const audioTypes = ["mp3", "wav", "aac", "flac", "ogg"];
+    if (audioTypes.includes(ext)) {
+      return G3FileIcons.file.audio;
+    }
+
+    // 视频类型
+    const videoTypes = ["mp4", "avi", "mkv", "mov", "wmv"];
+    if (videoTypes.includes(ext)) {
+      return G3FileIcons.file.video;
+    }
+
+    if (ext === "txt") {
+      return G3FileIcons.file.txt;
+    }
+
+    if (ext === "pdf") {
+      return G3FileIcons.file.pdf;
+    }
+
+    // 文档类型
+    const documentTypes = ["docx", "xlsx", "pptx", "office"];
+    if (documentTypes.includes(ext)) {
+      return G3FileIcons.file.docs;
+    }
+
+    // 压缩包类型
+    const archiveTypes = ["zip", "rar", "tar", "gz"];
+    if (archiveTypes.includes(ext)) {
+      return G3FileIcons.file.zip;
+    }
+
+    return G3FileIcons.file.default;
+  },
+
+  /**
+   * 获取唯一文件名
+   * @param {string} fileName - 原始文件名
+   * @param {Set} files - 已存在的文件名集合
+   * @returns {string} 唯一文件名
+   */
+  getUniqueFileName: function (fileName, files) {
+    const originalFileName = fileName;
+    let uniqueFileName = fileName;
+    let counter = 1;
+
+    while (files.has(uniqueFileName)) {
+      const fileNameWithoutExtension = originalFileName.replace(
+        /\.[^/.]+$/,
+        "",
+      );
+      const extension = originalFileName.slice(
+        originalFileName.lastIndexOf("."),
+      );
+      uniqueFileName = `${fileNameWithoutExtension} (${counter})${extension}`;
+      counter++;
+    }
+
+    return uniqueFileName;
+  },
+
+  /**
+   * 压缩图片
+   * @param {File} file - 图片文件
+   * @param {Object} options - 压缩选项
+   * @returns {Promise<File|Blob>} 压缩后的文件
+   */
+  compressImage: async function (file, options = {}) {
+    const {
+      minSize = 300 * 1024,
+      maxSize = 1.2 * 1024 * 1024,
+      maxWidth = 1920,
+      maxHeight = 1920,
+    } = options;
+
+    if (!file || !file.type.startsWith("image/")) return file;
+
+    const originSize = file.size;
+
+    if (originSize <= maxSize) {
+      return file;
+    }
+
+    const img = await new Promise((resolve, reject) => {
+      const reader = new FileReader();
+      reader.onload = () => {
+        const image = new Image();
+        image.onload = () => resolve(image);
+        image.onerror = reject;
+        image.src = reader.result;
+      };
+      reader.onerror = reject;
+      reader.readAsDataURL(file);
+    });
+
+    const canvas = document.createElement("canvas");
+    const ctx = canvas.getContext("2d");
+
+    let w = img.width;
+    let h = img.height;
+
+    const scale = Math.min(1, maxWidth / w, maxHeight / h);
+    w = Math.round(w * scale);
+    h = Math.round(h * scale);
+
+    canvas.width = w;
+    canvas.height = h;
+    ctx.drawImage(img, 0, 0, w, h);
+
+    const getBlob = (q) =>
+      new Promise((resolve) => {
+        canvas.toBlob((b) => resolve(b), "image/jpeg", q);
+      });
+
+    let quality = 0.92;
+
+    if (originSize > 4 * 1024 * 1024) {
+      quality = 0.88;
+    }
+
+    const blob = await getBlob(quality);
+
+    if (blob && blob.size < minSize) {
+      const safe = await getBlob(0.97);
+      return safe || file;
+    }
+
+    return blob || file;
+  },
+
+  /**
+   * 生成唯一ID
+   * @returns {string} 唯一ID
+   */
+  generateUniqueId: function () {
+    return "file_" + Math.random().toString(36).slice(2) + Date.now();
+  },
+
+  /**
+   * Base64 编码
+   * @param {string} str - 字符串
+   * @returns {string} Base64 编码结果
+   */
+  base64Encode: function (str) {
+    return btoa(
+      encodeURIComponent(str).replace(/%([0-9A-F]{2})/g, function (match, p1) {
+        return String.fromCharCode("0x" + p1);
+      }),
+    );
+  },
+};