Fix lint error

src/browser/index.js

@@ -1,98 +1,61 @@
-var defaultOptions = {
-    // workerPath: 'https://cdn.jsdelivr.net/gh/naptha/tesseract.js@0.2.0/dist/worker.js',
-    corePath: 'https://cdn.jsdelivr.net/gh/naptha/tesseract.js-core@0.1.0/index.js',    
-    langPath: 'https://cdn.jsdelivr.net/gh/naptha/tessdata@gh-pages/3.02/',
+const isURL = require('is-url');
+
+const defaultOptions = {
+  // workerPath: 'https://cdn.jsdelivr.net/gh/naptha/tesseract.js@0.2.0/dist/worker.js',
+  corePath: 'https://cdn.jsdelivr.net/gh/naptha/tesseract.js-core@0.1.0/index.js',
+  langPath: 'https://cdn.jsdelivr.net/gh/naptha/tessdata@gh-pages/3.02/',
+};
+
+if (process.env.NODE_ENV === 'development') {
+  console.debug('Using Development Configuration');
+  // eslint-disable-next-line
+  const { protocol, host } = location;
+  defaultOptions.workerPath = `${protocol}://${host}/dist/worker.dev.js?nocache=${Math.random().toString(36).slice(3)}`;
+} else {
+  const { version } = require('../../package.json');
+  defaultOptions.workerPath = `https://cdn.jsdelivr.net/gh/naptha/tesseract.js@${version}/dist/worker.js`;
 }
 
-if (process.env.NODE_ENV === "development") {
-    console.debug('Using Development Configuration')
-    defaultOptions.workerPath = location.protocol + '//' + location.host + '/dist/worker.dev.js?nocache=' + Math.random().toString(36).slice(3)
-}else{
-    var version = require('../../package.json').version;
-    defaultOptions.workerPath = 'https://cdn.jsdelivr.net/gh/naptha/tesseract.js@' + version + '/dist/worker.js'
-}
+const loadImage = (imageURI) => {
+  if (isURL(imageURI)) {
+    return fetch(imageURI)
+      .then(resp => resp.buffer());
+  }
+  return new Promise();
+};
 
 exports.defaultOptions = defaultOptions;
 
-
-exports.spawnWorker = function spawnWorker(instance, workerOptions){
-    if(window.Blob && window.URL){
-        var blob = new Blob(['importScripts("' + workerOptions.workerPath + '");'])
-        var worker = new Worker(window.URL.createObjectURL(blob));
-    }else{
-        var worker = new Worker(workerOptions.workerPath)
-    }
-
-    worker.onmessage = function(e){
-        var packet = e.data;
-        instance._recv(packet)
-    }
-    return worker
-}
-
-exports.terminateWorker = function(instance){
-    instance.worker.terminate()
-}
-
-exports.sendPacket = function sendPacket(instance, packet){
-    loadImage(packet.payload.image, function(img){
-        packet.payload.image = img
-        instance.worker.postMessage(packet) 
-    })
-}
-
-
-function loadImage(image, cb){
-    if(typeof image === 'string'){
-        if(/^\#/.test(image)){
-            // element css selector
-            return loadImage(document.querySelector(image), cb)
-        }else if(/(blob|data)\:/.test(image)){
-            // data url
-            var im = new Image
-            im.src = image;
-            im.onload = e => loadImage(im, cb);
-            return
-        }else{
-            var xhr = new XMLHttpRequest();
-            xhr.open('GET', image, true)
-            xhr.responseType = "blob";
-            xhr.onload = e => loadImage(xhr.response, cb);
-            xhr.onerror = function(e){
-                if(/^https?:\/\//.test(image) && !/^https:\/\/crossorigin.me/.test(image)){
-                    console.debug('Attempting to load image with CORS proxy')
-                    loadImage('https://crossorigin.me/' + image, cb)
-                }
-            }
-            xhr.send(null)
-            return
-        }
-    }else if(image instanceof File){
-        // files
-        var fr = new FileReader()
-        fr.onload = e => loadImage(fr.result, cb);
-        fr.readAsDataURL(image)
-        return
-    }else if(image instanceof Blob){
-        return loadImage(URL.createObjectURL(image), cb)
-    }else if(image.getContext){
-        // canvas element
-        return loadImage(image.getContext('2d'), cb)
-    }else if(image.tagName == "IMG" || image.tagName == "VIDEO"){
-        // image element or video element
-        var c = document.createElement('canvas');
-        c.width  = image.naturalWidth  || image.videoWidth;
-        c.height = image.naturalHeight || image.videoHeight;
-        var ctx = c.getContext('2d');
-        ctx.drawImage(image, 0, 0);
-        return loadImage(ctx, cb)
-    }else if(image.getImageData){
-        // canvas context
-        var data = image.getImageData(0, 0, image.canvas.width, image.canvas.height);
-        return loadImage(data, cb)
-    }else{
-        return cb(image)
-    }
-    throw new Error('Missing return in loadImage cascade')
-
-}
+exports.spawnWorker = (instance, workerOptions) => {
+  let worker;
+  if (window.Blob && window.URL) {
+    const blob = new Blob([`importScripts("${workerOptions.workerPath}");`]);
+    worker = new Worker(window.URL.createObjectURL(blob));
+  } else {
+    worker = new Worker(workerOptions.workerPath);
+  }
+
+  worker.onmessage = ({ data }) => {
+    instance._recv(data);
+  };
+
+  return worker;
+};
+
+exports.terminateWorker = (instance) => {
+  instance.worker.terminate();
+};
+
+exports.sendPacket = (instance, packet) => {
+  loadImage(packet.payload.image)
+    .then(buf => new Uint8Array(buf))
+    .then((img) => {
+      instance.worker.postMessage({
+        ...packet,
+        payload: {
+          ...packet.payload,
+          image: Array.from(img),
+        },
+      });
+    });
+};