chore: migration to typescript (#18)

Author: EscapedGibbon

.eslintrc.yml

@@ -11,4 +11,4 @@ jobs:
     # Documentation: https://github.com/zakodium/workflows#nodejs-ci
     uses: zakodium/workflows/.github/workflows/nodejs.yml@nodejs-v1
     with:
-      node-version-matrix: '[14, 16, 18]'
+      lint-check-types: true

.github/workflows/nodejs.yml

@@ -1,2 +1,4 @@
 node_modules
-coverage
+coverage
+lib
+lib-esm

.gitignore

@@ -0,0 +1,4 @@
+module.exports = {
+  presets: ['@babel/preset-typescript'],
+  plugins: ['@babel/plugin-transform-modules-commonjs'],
+};

babel.config.js

@@ -0,0 +1,14 @@
+import cheminfo from 'eslint-config-cheminfo-typescript';
+import globals from 'globals';
+
+export default [
+  ...cheminfo,
+  {
+    languageOptions: {
+      globals: {
+        ...globals.jest,
+        ...globals.node,
+      },
+    },
+  },
+];

eslint.config.mjs

@@ -2,29 +2,45 @@
   "name": "fast-bmp",
   "version": "2.0.1",
   "description": "A bmp image encoder",
-  "main": "src/index.js",
+  "main": "./lib/index.js",
+  "module": "./lib-esm/index.js",
+  "types": "./lib/index.d.ts",
   "repository": "[email protected]:image-js/fast-bmp.git",
   "author": "Daniel Kostro <[email protected]>",
   "license": "MIT",
+  "files": [
+    "src",
+    "lib",
+    "lib-esm"
+  ],
   "dependencies": {
-    "iobuffer": "^5.1.0"
+    "iobuffer": "^5.4.0"
   },
   "devDependencies": {
-    "@jest/globals": "^29.1.1",
-    "eslint": "^8.24.0",
-    "eslint-config-cheminfo": "^8.0.2",
+    "@babel/plugin-transform-modules-commonjs": "^7.26.3",
+    "@babel/preset-typescript": "^7.26.0",
+    "@types/jest": "^29.5.14",
+    "eslint": "^9.21.0",
+    "eslint-config-cheminfo-typescript": "^17.0.0",
     "jest": "^29.1.1",
-    "prettier": "^2.7.1"
+    "prettier": "^2.7.1",
+    "rimraf": "^6.0.1",
+    "typescript": "^5.8.2"
   },
   "scripts": {
     "eslint": "eslint src",
     "eslint-fix": "eslint --fix src",
     "prettier": "prettier --check src",
     "prettier-write": "prettier --write src",
-    "test": "npm run test-only && npm run eslint && npm run prettier",
+    "test": "npm run test-only && npm run eslint && npm run prettier && npm run check-types",
     "test-only": "jest --coverage",
-    "test-watch": "jest --watch",
-    "test-write": "FAST_BMP_WRITE_DATA_FILES=1 npm run test-jest"
+    "test-write": "FAST_BMP_WRITE_DATA_FILES=1 npm run test-only",
+    "check-types": "tsc --noEmit",
+    "clean": "rimraf lib lib-esm",
+    "prepack": "npm run tsc",
+    "tsc": "npm run clean && npm run tsc-cjs && npm run tsc-esm",
+    "tsc-cjs": "tsc --project tsconfig.cjs.json",
+    "tsc-esm": "tsc --project tsconfig.esm.json"
   },
   "jest": {
     "testEnvironment": "node"

package.json

@@ -1,16 +1,47 @@
-'use strict';
+import { IOBuffer } from 'iobuffer';
 
-const { IOBuffer } = require('iobuffer');
+import { BITMAPV5HEADER } from './constants';
 
-const constants = require('./constants');
+export interface DataToEncode {
+  /**
+   * Image bit depth.
+   */
+  bitDepth: number;
+  /**
+   * Image height.
+   */
+  height: number;
+  /**
+   * Image width.
+   */
+  width: number;
+  /**
+   * Image data.
+   */
+  data: IOBuffer | ArrayBufferLike | ArrayBufferView | Buffer;
+  /**
+   * Image number of channels.
+   */
+  channels: number;
+  /**
+   * Image number of channels excluding alpha.
+   */
+  components: number;
+}
 
-const tableLeft = [];
+const tableLeft: number[] = [];
 for (let i = 0; i <= 8; i++) {
   tableLeft.push(0b11111111 << i);
 }
 
-class BMPEncoder extends IOBuffer {
-  constructor(data) {
+export default class BMPEncoder extends IOBuffer {
+  width: number;
+  height: number;
+  bitDepth: number;
+  channels: number;
+  components: number;
+  encoded: IOBuffer = new IOBuffer();
+  constructor(data: DataToEncode) {
     if (data.bitDepth !== 1) {
       throw new Error('Only bitDepth of 1 is supported');
     }
@@ -34,20 +65,20 @@ class BMPEncoder extends IOBuffer {
     this.writeColorTable();
     const offset = this.encoded.offset;
     this.writePixelArray();
+    const imageSize = this.encoded.getWrittenByteLength();
     this.encoded.rewind();
-    this.writeBitmapFileHeader(offset);
+    this.writeBitmapFileHeader(offset, imageSize);
     return this.encoded.toArray();
   }
 
   writePixelArray() {
-    let io = this.encoded;
+    const io = this.encoded;
     const rowSize = Math.floor((this.bitDepth * this.width + 31) / 32) * 4;
     const dataRowSize = Math.ceil((this.bitDepth * this.width) / 8);
     const skipSize = rowSize - dataRowSize;
     const bitOverflow = (this.bitDepth * this.width) % 8;
     const bitSkip = bitOverflow === 0 ? 0 : 8 - bitOverflow;
     const totalBytes = rowSize * this.height;
-
     let byteA, byteB;
     let offset = 0; // Current off set in the ioData
     let relOffset = 0;
@@ -62,6 +93,7 @@ class BMPEncoder extends IOBuffer {
         const lastCol = j === dataRowSize - 1;
         if (relOffset <= bitSkip && lastCol) {
           // no need to read new data
+
           io.writeByte(byteB << relOffset);
           if ((bitSkip === 0 || bitSkip === relOffset) && !lastRow) {
             byteA = byteB;
@@ -70,6 +102,7 @@ class BMPEncoder extends IOBuffer {
         } else if (relOffset === 0) {
           byteA = byteB;
           byteB = this.readUint8();
+
           io.writeByte(byteA);
         } else {
           byteA = byteB;
@@ -78,6 +111,7 @@ class BMPEncoder extends IOBuffer {
             ((byteA << relOffset) & tableLeft[relOffset]) | (byteB >> iOffset)
           );
         }
+
         if (lastCol) {
           offset += bitOverflow || 0;
           io.skip(skipSize);
@@ -101,10 +135,10 @@ class BMPEncoder extends IOBuffer {
       .writeUint32(0x00ffffff); // white
   }
 
-  writeBitmapFileHeader(imageOffset) {
+  writeBitmapFileHeader(imageOffset: number, fileSize: number) {
     this.encoded
       .writeChars('BM') // 14 bytes bitmap file header
-      .writeInt32(this.encoded.lastWrittenByte) // Size of BMP file in bytes
+      .writeInt32(fileSize) // Size of BMP file in bytes
       .writeUint16(0)
       .writeUint16(0)
       .writeUint32(imageOffset);
@@ -120,22 +154,20 @@ class BMPEncoder extends IOBuffer {
       .writeInt32(this.height) // bV5Height
       .writeUint16(1) // bv5Planes - must be set to 1
       .writeUint16(this.bitDepth) // bV5BitCount
-      .writeUint32(constants.BITMAPV5HEADER.Compression.BI_RGB) // bV5Compression - No compression
+      .writeUint32(BITMAPV5HEADER.Compression.BI_RGB) // bV5Compression - No compression
       .writeUint32(totalBytes) // bv5SizeImage - size of pixel buffer (can be 0 if uncompressed)
       .writeInt32(0) // bV5XPelsPerMeter - resolution
       .writeInt32(0) // bV5YPelsPerMeter - resolution
-      .writeUint32(Math.pow(2, this.bitDepth))
-      .writeUint32(Math.pow(2, this.bitDepth))
+      .writeUint32(2 ** this.bitDepth)
+      .writeUint32(2 ** this.bitDepth)
       .writeUint32(0xff000000) // bV5RedMask
       .writeUint32(0x00ff0000) // bV5GreenMask
       .writeUint32(0x0000ff00) // bV5BlueMask
       .writeUint32(0x000000ff) // bV5AlphaMask
-      .writeUint32(constants.BITMAPV5HEADER.LogicalColorSpace.LCS_sRGB)
+      .writeUint32(BITMAPV5HEADER.LogicalColorSpace.LCS_sRGB)
       .skip(36) // bV5Endpoints
       .skip(12) // bV5GammaRed, Green, Blue
-      .writeUint32(constants.BITMAPV5HEADER.GamutMappingIntent.LCS_GM_IMAGES)
+      .writeUint32(BITMAPV5HEADER.GamutMappingIntent.LCS_GM_IMAGES)
       .skip(12); // ProfileData, ProfileSize, Reserved
   }
 }
-
-module.exports = BMPEncoder;

src/BMPEncoder.js renamed to src/BMPEncoder.ts

@@ -1,12 +1,14 @@
-'use strict';
-
-const testEncode = require('./testEncode');
+import { testEncode } from './testEncode';
 
 const data = {
+  width: 0,
+  height: 0,
+  data: new Uint8Array(),
   bitDepth: 1,
   components: 1,
   channels: 1,
 };
+
 describe('encode image with bitDepth of 1', () => {
   it('encode a 5x5 image', () => {
     // 0 0 0 0 0
@@ -91,7 +93,6 @@ describe('encode image with bitDepth of 1', () => {
     ]);
     testEncode(data, '42x2.bmp');
   });
-
   it('encode image where skipBit can equal relOffset on the last column', () => {
     data.width = 60;
     data.height = 4;

src/__test__/bitDepth1.test.js renamed to src/__test__/bitDepth1.test.ts

@@ -1,6 +1,4 @@
-'use strict';
-
-const encode = require('..').encode;
+import { encode } from '..';
 
 describe('errors', () => {
   it('should throw if width or height are undefined or 0', () => {
@@ -18,6 +16,7 @@ describe('errors', () => {
     expect(() => {
       encode({
         width: 10,
+        height: 0,
         components: 1,
         bitDepth: 1,
         channels: 1,

src/__test__/errors.test.js renamed to src/__test__/errors.test.ts

@@ -1,13 +1,15 @@
-'use strict';
+import fs from 'node:fs';
+import path from 'node:path';
 
-const fs = require('fs');
-const path = require('path');
+import { encode } from '..';
+import type { DataToEncode } from '../BMPEncoder';
 
-const { expect } = require('@jest/globals');
-
-const encode = require('..').encode;
-
-module.exports = function testEncode(data, filename) {
+/**
+ * Testing function for BMP encoding.
+ * @param data - Data for encoding.
+ * @param filename - Filename for a file to write.
+ */
+export function testEncode(data: DataToEncode, filename: string) {
   const buffer = encode(data);
   if (process.env.FAST_BMP_WRITE_DATA_FILES) {
     fs.writeFileSync(path.join(__dirname, 'files', filename), buffer);
@@ -16,4 +18,4 @@ module.exports = function testEncode(data, filename) {
     const fileDataUint8 = Uint8Array.from(fileData);
     expect(buffer).toStrictEqual(fileDataUint8);
   }
-};
+}