George / FEQ-1990 / Transfer file utils

src/constants/document.constants.ts

@@ -0,0 +1,3 @@
+export const supportedDocumentFormats = ["PNG", "JPG", "JPEG", "GIF", "PDF"] as const;
+
+export type DocumentFormats = (typeof supportedDocumentFormats)[number];

src/constants/index.ts

@@ -1,7 +1,15 @@
 import * as AppIDConstants from "./app-id.constants";
 import * as CurrencyConstants from "./currency.constants";
+import * as DocumentConstants from "./document.constants";
 import * as LocalStorageConstants from "./localstorage.constants";
 import * as URLConstants from "./url.constants";
 import * as ValidationConstants from "./validation.constants";
 
-export { AppIDConstants, CurrencyConstants, LocalStorageConstants, URLConstants, ValidationConstants };
+export {
+    AppIDConstants,
+    CurrencyConstants,
+    DocumentConstants,
+    LocalStorageConstants,
+    URLConstants,
+    ValidationConstants,
+};

src/utils/__test__/image.utils.spec.ts

@@ -0,0 +1,97 @@
+import { convertToBase64, isSupportedImageFormat } from "../image.utils";
+import { describe, test, expect } from "vitest";
+
+describe("convertToBase64()", () => {
+    const mockImageFile = new File(["image-data-contents"], "image1.jpg", { type: "image/jpeg" });
+
+    test("should convert a File to base64", async () => {
+        const base64Image = await convertToBase64(mockImageFile);
+
+        expect(base64Image).toEqual(
+            expect.objectContaining({
+                src: expect.any(String),
+                filename: "image1.jpg",
+            }),
+        );
+
+        expect(base64Image.src).toMatch(/^data:image\/jpeg;base64,/);
+    });
+
+    test("should handle empty files", async () => {
+        const mockFile = new File([], "empty.txt", { type: "text/plain" });
+        const base64Image = await convertToBase64(mockFile);
+
+        expect(base64Image).toEqual(
+            expect.objectContaining({
+                src: "data:text/plain;base64,",
+                filename: "empty.txt",
+            }),
+        );
+    });
+
+    test("should handle files with special characters in their names", async () => {
+        const mockFile = new File(["file contents"], "special&chars.jpg", { type: "image/jpeg" });
+        const base64Image = await convertToBase64(mockFile);
+
+        expect(base64Image).toEqual(
+            expect.objectContaining({
+                src: expect.any(String),
+                filename: "special&chars.jpg",
+            }),
+        );
+
+        expect(base64Image.src).toMatch(/^data:image\/jpeg;base64,/);
+    });
+
+    test("should handle non-image files", async () => {
+        const mockFile = new File(["file contents"], "document.pdf", { type: "application/pdf" });
+        const base64Image = await convertToBase64(mockFile);
+
+        expect(base64Image).toEqual(
+            expect.objectContaining({
+                src: expect.any(String),
+                filename: "document.pdf",
+            }),
+        );
+
+        expect(base64Image.src).toMatch(/^data:application\/pdf;base64,/);
+    });
+
+    test("should handle files with no type information", async () => {
+        const mockFile = new File(["file contents"], "unknown", { type: "" });
+        const base64Image = await convertToBase64(mockFile);
+
+        expect(base64Image).toEqual(
+            expect.objectContaining({
+                src: expect.any(String),
+                filename: "unknown",
+            }),
+        );
+    });
+});
+
+describe("isSupportedImageFormat()", () => {
+    test("should return true for supported image formats", () => {
+        expect(isSupportedImageFormat("image1.png")).toBe(true);
+        expect(isSupportedImageFormat("image1.jpg")).toBe(true);
+        expect(isSupportedImageFormat("image1.jpeg")).toBe(true);
+        expect(isSupportedImageFormat("image1.gif")).toBe(true);
+        expect(isSupportedImageFormat("document.pdf")).toBe(true);
+        expect(isSupportedImageFormat("mixed.CaSe.JPeG")).toBe(true);
+    });
+
+    test("should return false for unsupported image formats", () => {
+        expect(isSupportedImageFormat("file.txt")).toBe(false);
+        expect(isSupportedImageFormat("document.docx")).toBe(false);
+        expect(isSupportedImageFormat("data.xml")).toBe(false);
+        expect(isSupportedImageFormat("fake-image.jpg.txt")).toBe(false);
+        expect(isSupportedImageFormat("compressed.jpg.rar")).toBe(false);
+    });
+
+    test("should handle edge cases", () => {
+        // @ts-expect-error - test case to simulate passing null
+        expect(isSupportedImageFormat(null)).toBe(false);
+        // @ts-expect-error - test case to simulate passing undefined
+        expect(isSupportedImageFormat(undefined)).toBe(false);
+    });
+});

src/utils/image.utils.ts

@@ -0,0 +1,200 @@
+import { DocumentConstants } from "../constants";
+
+const DEFAULT_IMAGE_WIDTH = 2560;
+const DEFAULT_IMAGE_QUALITY = 0.9;
+const WORD_SIZE = 4;
+
+interface IExtendedBlob extends Blob {
+    lastModifiedDate?: number;
+    name?: string;
+}
+
+type TCompressImageOption = {
+    maxWidth?: number;
+    quality?: number;
+};
+
+type TBase64Image = {
+    filename: string;
+    src: string;
+};
+
+type TCompressImage = TBase64Image & {
+    options?: TCompressImageOption;
+};
+
+export type TFileObject = {
+    filename?: File["name"];
+    buffer: FileReader["result"];
+    fileSize: File["size"];
+};
+
+/**
+ * Compress an image and return it as a Blob.
+ * @param {TCompressImage} params - The parameters for image compression.
+ * @param {string} params.src - The source image URL or data URI.
+ * @param {string} params.filename - The desired filename for the compressed image.
+ * @param {Object} [params.options] - Options for image compression.
+ * @param {number} [params.options.maxWidth=DEFAULT_IMAGE_WIDTH] - The maximum width for the compressed image.
+ * @param {number} [params.options.quality=DEFAULT_IMAGE_QUALITY] - The image quality (0 to 1) for compression.
+ * @returns {Promise<IExtendedBlob>} A Promise that resolves with the compressed image as a Blob.
+ */
+export const compressImage = ({ src, filename, options }: TCompressImage): Promise<IExtendedBlob> => {
+    const { maxWidth = DEFAULT_IMAGE_WIDTH, quality = DEFAULT_IMAGE_QUALITY } = options || {};
+
+    return new Promise((resolve, reject) => {
+        const image = new Image();
+        image.src = src;
+        image.onload = () => {
+            const canvas = document.createElement("canvas");
+            const canvas_context = canvas.getContext("2d");
+            if (!canvas_context || !(canvas_context instanceof CanvasRenderingContext2D)) {
+                return reject(new Error("Failed to get 2D context"));
+            }
+
+            if (image.naturalWidth > maxWidth) {
+                const width = DEFAULT_IMAGE_WIDTH;
+                const scaleFactor = width / image.naturalWidth;
+                canvas.width = width;
+                canvas.height = image.naturalHeight * scaleFactor;
+            } else {
+                canvas.width = image.naturalWidth;
+                canvas.height = image.naturalHeight;
+            }
+
+            canvas_context.fillStyle = "transparent";
+            canvas_context.fillRect(0, 0, canvas.width, canvas.height);
+            canvas_context.save();
+            canvas_context.drawImage(image, 0, 0, canvas.width, canvas.height);
+
+            canvas.toBlob(
+                (blob) => {
+                    if (!blob) return;
+                    const modified_filename = filename.replace(/\.[^/.]+$/, ".jpg");
+                    const file: IExtendedBlob = new Blob([blob], { type: "image/jpeg" });
+                    file.lastModifiedDate = Date.now();
+                    file.name = modified_filename;
+                    resolve(file);
+                },
+                "image/jpeg",
+                quality,
+            );
+        };
+    });
+};
+
+/**
+ * Convert a File to a Base64 encoded image representation.
+ * @param {File} file - The File object to convert to Base64.
+ * @returns {Promise<TBase64Image>} A Promise that resolves with an object containing the Base64 image data and the filename.
+ */
+export const convertToBase64 = (file: File): Promise<TBase64Image> => {
+    return new Promise((resolve) => {
+        const reader = new FileReader();
+        reader.readAsDataURL(file);
+        reader.onloadend = () => {
+            resolve({
+                src: reader.result?.toString() || "",
+                filename: file.name,
+            });
+        };
+    });
+};
+
+/**
+ * Check if a given filename has a supported image format extension.
+ *
+ * @param {string} filename - The filename to check for a supported image format.
+ * @returns {boolean} True if the filename has a supported image format extension, false otherwise.
+ */
+export const isSupportedImageFormat = (filename: string) => {
+    if (!filename) return false;
+
+    return DocumentConstants.supportedDocumentFormats.some((documentFormat) =>
+        filename.toUpperCase().endsWith(documentFormat),
+    );
+};
+
+/**
+ * Convert image to base64 and compress an image file if it is a supported image format.
+ *
+ * @param {File} file - The File object to compress.
+ * @returns {Promise<Blob>} A Promise that resolves with the compressed image as a Blob.
+ */
+export const compressImageFile = (file: File) => {
+    return new Promise<Blob>((resolve) => {
+        if (isSupportedImageFormat(file.name)) {
+            convertToBase64(file).then((img) => {
+                compressImage(img).then(resolve);
+            });
+        } else {
+            resolve(file);
+        }
+    });
+};
+
+/**
+ * Get Uint8Array from number
+ *
+ * @param {num} number - The number to convert to Uint8Array.
+ * @returns {Uint8Array} Uint8Array
+ */
+export function numToUint8Array(num: number, arraySize = WORD_SIZE) {
+    const typedArray = new Uint8Array(arraySize);
+    const dv = new DataView(typedArray.buffer);
+    dv.setUint32(0, num);
+    return typedArray;
+}
+
+/**
+ * Turn binary into array of chunks
+ *
+ * @param {binary} Uint8Array - Uint8Array to be chunked.
+ * @returns {Uint8Array[]} Array of Uint8Array chunks
+ */
+export const generateChunks = (binary: Uint8Array, { chunkSize = 16384 /* 16KB */ }) => {
+    const chunks = [];
+    for (let i = 0; i < binary.length; i++) {
+        const item = binary[i];
+        if (i % chunkSize === 0) {
+            chunks.push([item]);
+        } else {
+            chunks[chunks.length - 1].push(item);
+        }
+    }
+    return chunks.map((b) => new Uint8Array(b)).concat(new Uint8Array([]));
+};
+
+/**
+ * Read a file and return it as modified object with a buffer of the file contents.
+ * @param {IExtendedBlob} file - The file to read.
+ * @returns {Promise<TFileObject>} A Promise that resolves with the file as a TFileObject.
+ *
+ */
+export const readFile = (file: IExtendedBlob) => {
+    const fr = new FileReader();
+    return new Promise<
+        | TFileObject
+        | {
+              message: string;
+          }
+    >((resolve) => {
+        fr.onload = () => {
+            const fileMetadata = {
+                filename: file.name,
+                buffer: fr.result,
+                fileSize: file.size,
+            };
+            resolve(fileMetadata);
+        };
+
+        fr.onerror = () => {
+            resolve({
+                message: `Unable to read file ${file.name}`,
+            });
+        };
+
+        // Reading file
+        fr.readAsArrayBuffer(file);
+    });
+};

src/utils/index.ts

@@ -1,8 +1,9 @@
 import * as FormatUtils from "./format.utils";
+import * as ImageUtils from "./image.utils";
 import * as LocalStorageUtils from "./localstorage.utils";
 import * as ObjectUtils from "./object.utils";
 import * as PromiseUtils from "./promise.utils";
 import * as URLUtils from "./url.utils";
 import * as WebSocketUtils from "./websocket.utils";
 
-export { FormatUtils, LocalStorageUtils, ObjectUtils, PromiseUtils, URLUtils, WebSocketUtils };
+export { ImageUtils, FormatUtils, LocalStorageUtils, ObjectUtils, PromiseUtils, URLUtils, WebSocketUtils };