Improve coverage for image upload and schedule helper logic with focused unit tests (#551)

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backend/src/test/image-upload.test.ts

@@ -0,0 +1,87 @@
+import { mkdtempSync, readFileSync, rmSync, writeFileSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import { Readable } from "node:stream";
+import sharp from "sharp";
+import { afterEach, describe, expect, it, vi } from "vitest";
+import {
+	getThumbFilename,
+	MAX_IMAGE_UPLOAD_BYTES,
+	removeImageFiles,
+	streamToBuffer,
+	writeOptimizedImageSet,
+} from "../utils/image-upload";
+
+describe("image-upload utils", () => {
+	const MOCK_TIMESTAMP_MS = 1_700_000_000_000;
+	const tempDirs: string[] = [];
+
+	afterEach(() => {
+		vi.restoreAllMocks();
+		for (const dir of tempDirs.splice(0)) {
+			rmSync(dir, { recursive: true, force: true });
+		}
+	});
+
+	it("builds thumb filename with and without extension", () => {
+		expect(getThumbFilename("avatar.png")).toBe("avatar-thumb.webp");
+		expect(getThumbFilename("avatar")).toBe("avatar-thumb.webp");
+	});
+
+	it("removes original and thumb files when they exist", () => {
+		const imagesDir = mkdtempSync(join(tmpdir(), "medassist-image-upload-"));
+		tempDirs.push(imagesDir);
+
+		const imageFilename = "profile.webp";
+		const imagePath = join(imagesDir, imageFilename);
+		const thumbPath = join(imagesDir, getThumbFilename(imageFilename));
+		writeFileSync(imagePath, Buffer.from("image"));
+		writeFileSync(thumbPath, Buffer.from("thumb"));
+
+		removeImageFiles(imagesDir, imageFilename);
+
+		expect(() => readFileSync(imagePath)).toThrow();
+		expect(() => readFileSync(thumbPath)).toThrow();
+	});
+
+	it("buffers stream chunks and rejects payloads above max size", async () => {
+		const stream = Readable.from([Buffer.from("hello"), Buffer.from("world")]);
+		await expect(streamToBuffer(stream)).resolves.toEqual(Buffer.from("helloworld"));
+
+		const oversized = Readable.from([Buffer.alloc(MAX_IMAGE_UPLOAD_BYTES + 1)]);
+		await expect(streamToBuffer(oversized)).rejects.toThrow("IMAGE_TOO_LARGE");
+	});
+
+	it("writes optimized full and thumbnail webp variants", async () => {
+		const imagesDir = mkdtempSync(join(tmpdir(), "medassist-image-upload-"));
+		tempDirs.push(imagesDir);
+		vi.spyOn(Date, "now").mockReturnValue(MOCK_TIMESTAMP_MS);
+
+		const uploadBuffer = await sharp({
+			create: {
+				width: 64,
+				height: 48,
+				channels: 3,
+				background: { r: 255, g: 0, b: 0 },
+			},
+		})
+			.png()
+			.toBuffer();
+
+		const result = await writeOptimizedImageSet(imagesDir, "med-42", uploadBuffer, {
+			maxEdgePx: 32,
+			thumbSizePx: 16,
+		});
+
+		expect(result.filename).toBe("med-42-1700000000000.webp");
+		expect(result.thumbFilename).toBe("med-42-1700000000000-thumb.webp");
+
+		const optimizedMeta = await sharp(join(imagesDir, result.filename)).metadata();
+		const thumbMeta = await sharp(join(imagesDir, result.thumbFilename)).metadata();
+		expect(optimizedMeta.format).toBe("webp");
+		expect(thumbMeta.format).toBe("webp");
+		expect(Math.max(optimizedMeta.width ?? 0, optimizedMeta.height ?? 0)).toBeLessThanOrEqual(32);
+		expect(thumbMeta.width).toBe(16);
+		expect(thumbMeta.height).toBe(16);
+	});
+});