refactor: improve code style

DimensionDev · Oct 11, 2022 · df9e3d7 · df9e3d7
1 parent c33a1c4
commit df9e3d7
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Showing 24 changed files with 216 additions and 284 deletions.
diff --git a/.changeset/modern-keys-bathe.md b/.changeset/modern-keys-bathe.md
@@ -0,0 +1,5 @@
+---
+'@dimensiondev/stego-js': minor
+---
+
+make exported type readonly as possible
diff --git a/.vscode/settings.json b/.vscode/settings.json
@@ -2,5 +2,6 @@
   "editor.formatOnSave": true,
   "editor.codeActionsOnSave": {
     "source.fixAll": true
-  }
+  },
+  "cSpell.words": ["stego", "unshuffle"]
 }
diff --git a/src/cli/cli.ts b/src/cli/cli.ts
@@ -1,7 +1,6 @@
 #!/usr/bin/env node
 import meow from 'meow'
 import { createReadStream } from 'fs'
-import { rs2Buf } from '../utils/helper.js'
 import { encode, decode, AlgorithmVersion } from '../node.js'
 import {
   CLI_NAME,
@@ -15,6 +14,17 @@ import {
   DEFAULT_ALGORITHM_VERSION,
 } from '../constant.js'
 import { normalizeFlags, validateFlags, flags2Options, flags } from './flag.js'
+import { Readable } from 'stream'
+
+function rs2Buf(rs: Readable) {
+  return new Promise<Buffer>((resolve, reject) => {
+    const buffers: Uint8Array[] = []
+
+    rs.on('data', (c) => buffers.push(c))
+    rs.on('end', () => resolve(Buffer.concat(buffers)))
+    rs.on('error', (err) => reject(err))
+  })
+}
 
 const cli = meow(
   `Usage

diff --git a/src/cli/flag.ts b/src/cli/flag.ts
@@ -126,10 +126,13 @@ export const flags = {
 } as const
 
 export function normalizeFlags(rawFlags: TypedFlags<typeof flags>) {
-  const { encode, decode, mask, tolerance } = rawFlags
+  const { encode, decode, mask, tolerance, transform } = rawFlags
   return {
     ...rawFlags,
-    tolerance: tolerance === TOLERANCE_NOT_SET ? DEFAULT_TOLERANCE[rawFlags.algorithmVersion].transform : tolerance,
+    tolerance:
+      tolerance === TOLERANCE_NOT_SET
+        ? DEFAULT_TOLERANCE[rawFlags.algorithmVersion as AlgorithmVersion][transform as TransformAlgorithm]
+        : tolerance,
     encode: encode && !decode,
     decode,
     mask: mask ? resolvePath(process.cwd(), mask) : '',
@@ -159,8 +162,8 @@ export function validateFlags({
   if (isNaN(copies) || copies <= 0 || copies % 2 === 0 || copies > 31) {
     return '-c, --copies should be a postive odd number and less than 31'
   }
-  // the valiadation for transform algorithm should prior to tolerance,
-  // becasue tolerance validation depends on transform algorithm
+  // the validation for transform algorithm should prior to tolerance,
+  // because tolerance validation depends on transform algorithm
   if (!Object.values(TransformAlgorithm).includes(transform)) {
     return 'unknown transform algorithm'
   }

diff --git a/src/constant.ts b/src/constant.ts
@@ -10,7 +10,7 @@ export const DEFAULT_COPIES = 3
 export const DEFAULT_PARAM_COPIES = 9
 export const DEFAULT_SIZE = 8
 export const TOLERANCE_NOT_SET = -1
-export const DEFAULT_TOLERANCE: Record<string, Record<string, number>> = {
+export const DEFAULT_TOLERANCE: Readonly<Record<AlgorithmVersion, Record<TransformAlgorithm, number>>> = Object.freeze({
   [AlgorithmVersion.V1]: {
     [TransformAlgorithm.DCT]: 100,
     [TransformAlgorithm.FastDCT]: 500,
@@ -23,26 +23,26 @@ export const DEFAULT_TOLERANCE: Record<string, Record<string, number>> = {
     [TransformAlgorithm.FFT1D]: 30,
     [TransformAlgorithm.FFT2D]: 150,
   },
-}
-export const MAX_TOLERANCE: Record<string, number> = {
+})
+export const MAX_TOLERANCE: Readonly<Record<TransformAlgorithm, number>> = Object.freeze({
   [TransformAlgorithm.DCT]: 5000,
   [TransformAlgorithm.FastDCT]: 5000,
   [TransformAlgorithm.FFT1D]: 5000,
   [TransformAlgorithm.FFT2D]: 50000,
-}
+})
 export const DEFAULT_FAKE_MASK_PIXELS = false
 export const DEFAULT_EXHAUST_PIXELS = true
 export const DEFAULT_CROP_EDGE_PIXELS = true
 export const DEFAULT_ALGORITHM_VERSION = AlgorithmVersion.V2
 
-export const DEFAULT_MASK = [
+export const DEFAULT_MASK = Object.freeze([
   137, 80, 78, 71, 13, 10, 26, 10, 0, 0, 0, 13, 73, 72, 68, 82, 0, 0, 0, 1, 0, 0, 0, 1, 1, 3, 0, 0, 0, 37, 219, 86, 202,
   0, 0, 0, 1, 115, 82, 71, 66, 1, 217, 201, 44, 127, 0, 0, 0, 9, 112, 72, 89, 115, 0, 0, 11, 19, 0, 0, 11, 19, 1, 0,
   154, 156, 24, 0, 0, 0, 3, 80, 76, 84, 69, 255, 255, 255, 167, 196, 27, 200, 0, 0, 0, 10, 73, 68, 65, 84, 120, 156, 99,
   96, 0, 0, 0, 2, 0, 1, 72, 175, 164, 113, 0, 0, 0, 0, 73, 69, 78, 68, 174, 66, 96, 130,
-]
+])
 
-export const SEED = [
+export const SEED = Object.freeze([
   76221, 13388, 20800, 80672, 15974, 87005, 71203, 84444, 16928, 51335, 94092, 83586, 37656, 2240, 26283, 1887, 93419,
   96857, 20866, 21797, 42065, 39781, 50192, 24399, 98969, 54274, 38815, 45159, 36824,
-]
+])
diff --git a/src/dct/fastdct.ts b/src/dct/fastdct.ts
@@ -23,8 +23,8 @@
 
 // DCT type II, unscaled. Algorithm by Byeong Gi Lee, 1984.
 // See: http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.118.3056&rep=rep1&type=pdf#page=34
-export function transform(vector: Array<number>): void {
-  const n: number = vector.length
+export function transform(vector: number[]): void {
+  const n = vector.length
   if (n <= 0 || (n & (n - 1)) !== 0) throw 'Length must be power of 2'
   transformInternal(vector, 0, n, new Float64Array(n))
 }

diff --git a/src/dct/index.ts b/src/dct/index.ts
@@ -4,7 +4,7 @@
 const ONE_SQUARE_ROOT_OF_TWO = 1 / Math.sqrt(2)
 
 // type-II DCT
-export function dct(nums: number[], size: number = 8) {
+export function dct(numbers: number[], size: number = 8) {
   const coefficients: number[] = []
 
   for (let v = 0; v < size; v += 1) {
@@ -16,7 +16,9 @@ export function dct(nums: number[], size: number = 8) {
       for (let y = 0; y < size; y += 1) {
         for (let x = 0; x < size; x += 1) {
           sum +=
-            nums[y * size + x] * Math.cos(((2 * x + 1) * u * Math.PI) / 16) * Math.cos(((2 * y + 1) * v * Math.PI) / 16)
+            numbers[y * size + x] *
+            Math.cos(((2 * x + 1) * u * Math.PI) / 16) *
+            Math.cos(((2 * y + 1) * v * Math.PI) / 16)
         }
       }
       coefficients.push((sum * au * av) / 4)
@@ -25,13 +27,13 @@ export function dct(nums: number[], size: number = 8) {
 
   // in-place update
   for (let i = 0; i < coefficients.length; i += 1) {
-    nums[i] = coefficients[i]
+    numbers[i] = coefficients[i]
   }
 }
 
 // type-III DCT
 export function idct(coefficients: number[], size: number = 8) {
-  const nums: number[] = []
+  const numbers: number[] = []
 
   for (let y = 0; y < size; y += 1) {
     for (let x = 0; x < size; x += 1) {
@@ -50,18 +52,12 @@ export function idct(coefficients: number[], size: number = 8) {
             Math.cos(((2 * y + 1) * v * Math.PI) / 16)
         }
       }
-      nums.push(sum / 4)
+      numbers.push(sum / 4)
     }
   }
 
   // in-place update
-  for (let i = 0; i < nums.length; i += 1) {
-    coefficients[i] = nums[i]
+  for (let i = 0; i < numbers.length; i += 1) {
+    coefficients[i] = numbers[i]
   }
 }
-
-export const QUANTIZATION_MATRIX = [
-  16, 11, 10, 16, 24, 40, 51, 61, 12, 12, 14, 19, 26, 58, 60, 55, 14, 13, 16, 24, 40, 57, 69, 56, 14, 17, 22, 29, 51,
-  87, 80, 62, 18, 22, 37, 56, 68, 109, 103, 77, 24, 35, 55, 64, 81, 104, 113, 92, 49, 64, 78, 87, 103, 121, 120, 101,
-  72, 92, 95, 98, 112, 100, 103, 99,
-]
diff --git a/src/dom.ts b/src/dom.ts
@@ -1,58 +1,50 @@
-import { proxy } from './utils/expose.js'
-import { imgType } from './utils/helper.js'
+import { createAPI } from './utils/expose.js'
+import { getImageType } from './utils/helper.js'
 import { preprocessImage } from './utils/image.js'
-import { AlgorithmVersion } from './utils/stego-params.js'
-import * as v1 from './v1/index.js'
-import * as v2 from './v2/index.js'
 
-export { imgType as getImageType }
+export { getImageType }
 export * from './utils/types.js'
 export * from './constant.js'
 
-const { encode, decode } = proxy({
-  algoithms: { [AlgorithmVersion.V1]: v1, [AlgorithmVersion.V2]: v2 },
-  methods: {
-    toImageData(data) {
-      const type = imgType(new Uint8Array(data.slice(0, 8)))
-      const blob = new Blob([data], { type })
-      const url = URL.createObjectURL(blob)
-      return new Promise((resolve, reject) => {
-        const element = new Image()
-        element.addEventListener('load', () => {
-          const { width, height } = element
-          const ctx = createCanvas(width, height).getContext('2d')!
-          ctx.drawImage(element, 0, 0, width, height)
-          resolve(ctx.getImageData(0, 0, width, height))
-        })
-        element.addEventListener('error', reject)
-        element.src = url
+export const { encode, decode } = createAPI({
+  toImageData(data) {
+    const type = getImageType(new Uint8Array(data.slice(0, 8)))
+    const blob = new Blob([data], { type })
+    const url = URL.createObjectURL(blob)
+    return new Promise((resolve, reject) => {
+      const element = new Image()
+      element.addEventListener('load', () => {
+        const { width, height } = element
+        const ctx = createCanvas(width, height).getContext('2d')!
+        ctx.drawImage(element, 0, 0, width, height)
+        resolve(ctx.getImageData(0, 0, width, height))
       })
-    },
-    async toBuffer(imgData, height = imgData.height, width = imgData.width) {
-      const canvas = createCanvas(width, height)
-      canvas.getContext('2d')!.putImageData(imgData, 0, 0, 0, 0, width, height)
-      if (isOffscreenCanvas(canvas)) {
-        return toArrayBuffer(await canvas.convertToBlob({ type: 'image/png' }))
-      }
-      return new Promise<ArrayBuffer>((resolve, reject) => {
-        const callback: BlobCallback = (blob) => {
-          if (blob) {
-            resolve(toArrayBuffer(blob))
-          } else {
-            reject(new Error('fail to generate array buffer'))
-          }
+      element.addEventListener('error', reject)
+      element.src = url
+    })
+  },
+  async toBuffer(imgData, height = imgData.height, width = imgData.width) {
+    const canvas = createCanvas(width, height)
+    canvas.getContext('2d')!.putImageData(imgData, 0, 0, 0, 0, width, height)
+    if (isOffscreenCanvas(canvas)) {
+      return toArrayBuffer(await canvas.convertToBlob({ type: 'image/png' }))
+    }
+    return new Promise<ArrayBuffer>((resolve, reject) => {
+      const callback: BlobCallback = (blob) => {
+        if (blob) {
+          resolve(toArrayBuffer(blob))
+        } else {
+          reject(new Error('fail to generate array buffer'))
         }
-        canvas.toBlob(callback, 'image/png')
-      })
-    },
-    preprocessImage(data) {
-      return preprocessImage(data, (w, h) => createCanvas(w, h).getContext('2d')?.createImageData(w, h) ?? null)
-    },
+      }
+      canvas.toBlob(callback, 'image/png')
+    })
+  },
+  preprocessImage(data) {
+    return preprocessImage(data, (w, h) => createCanvas(w, h).getContext('2d')?.createImageData(w, h) ?? null)
   },
 })
 
-export { encode, decode }
-
 function toArrayBuffer(blob: Blob) {
   return new Promise<ArrayBuffer>((resolve, reject) => {
     const reader = new FileReader()

diff --git a/src/node.ts b/src/node.ts
@@ -1,57 +1,49 @@
 import { JsColorType, Transformer } from '@napi-rs/image'
-import { proxy } from './utils/expose.js'
-import { imgType } from './utils/helper.js'
+import { createAPI } from './utils/expose.js'
+import { getImageType } from './utils/helper.js'
 import { preprocessImage } from './utils/image.js'
-import { AlgorithmVersion } from './utils/stego-params.js'
-import * as v1 from './v1/index.js'
-import * as v2 from './v2/index.js'
 
-export { imgType as getImageType }
+export { getImageType }
 export * from './utils/types.js'
 export * from './constant.js'
 
-const { encode, decode } = proxy({
-  algoithms: { [AlgorithmVersion.V1]: v1, [AlgorithmVersion.V2]: v2 },
-  methods: {
-    async toImageData(data) {
-      let transformer = new Transformer(Buffer.from(data))
-      let { width, height, colorType } = await transformer.metadata()
+export const { encode, decode } = createAPI({
+  async toImageData(data) {
+    let transformer = new Transformer(Buffer.from(data))
+    let { width, height, colorType } = await transformer.metadata()
 
-      if (colorType !== JsColorType.Rgba8 && colorType !== JsColorType.Rgb8) {
-        transformer = new Transformer(await transformer.png())
-        ;({ width, height, colorType } = await transformer.metadata())
-      }
+    if (colorType !== JsColorType.Rgba8 && colorType !== JsColorType.Rgb8) {
+      transformer = new Transformer(await transformer.png())
+      ;({ width, height, colorType } = await transformer.metadata())
+    }
 
-      if (colorType !== JsColorType.Rgba8 && colorType !== JsColorType.Rgb8) {
-        throw new TypeError('Cannot convert the given image to rgba8 format.')
-      }
-      let rgb: Uint8ClampedArray = new Uint8ClampedArray(await transformer.rawPixels())
-      if (colorType === JsColorType.Rgb8) rgb = rgb_to_rgba(rgb)
+    if (colorType !== JsColorType.Rgba8 && colorType !== JsColorType.Rgb8) {
+      throw new TypeError('Cannot convert the given image to rgba8 format.')
+    }
+    let rgb: Uint8ClampedArray = new Uint8ClampedArray(await transformer.rawPixels())
+    if (colorType === JsColorType.Rgb8) rgb = rgb_to_rgba(rgb)
 
-      const imageData: ImageData = {
-        width,
-        height,
-        colorSpace: 'srgb',
-        data: rgb,
-      }
-      return imageData
-    },
-    async toBuffer(imgData, height = imgData.height, width = imgData.width) {
-      return (await Transformer.fromRgbaPixels(imgData.data, width, height).crop(0, 0, width, height).png()).buffer
-    },
-    preprocessImage(data) {
-      return preprocessImage(data, (width, height) => ({
-        height,
-        width,
-        colorSpace: 'srgb',
-        data: new Uint8ClampedArray(width * height * 4),
-      }))
-    },
+    const imageData: ImageData = {
+      width,
+      height,
+      colorSpace: 'srgb',
+      data: rgb,
+    }
+    return imageData
+  },
+  async toBuffer(imgData, height = imgData.height, width = imgData.width) {
+    return (await Transformer.fromRgbaPixels(imgData.data, width, height).crop(0, 0, width, height).png()).buffer
+  },
+  preprocessImage(data) {
+    return preprocessImage(data, (width, height) => ({
+      height,
+      width,
+      colorSpace: 'srgb',
+      data: new Uint8ClampedArray(width * height * 4),
+    }))
   },
 })
 
-export { encode, decode }
-
 function rgb_to_rgba(array: Uint8ClampedArray) {
   const next = new Uint8ClampedArray((array.length / 3) * 4)
   for (var old_index = 0, new_index = 0; old_index < array.length; old_index += 3, new_index += 4) {