Translation extension imports translated language names (#1159)

* wip

* wip

* Get viewer language code, and cleanup

* Revert "wip"

This reverts commit 6598738ed2.

# Conflicts:
#	src/extensions/scratch3_translate/index.js

package.json

@@ -61,6 +61,7 @@
     "scratch-parser": "4.1.1",
     "scratch-render": "latest",
     "scratch-storage": "^0.4.0",
+    "scratch-translate-extension-languages": "0.0.20180521154850",
     "script-loader": "0.7.2",
     "socket.io-client": "2.0.4",
     "stats.js": "^0.17.0",

src/extensions/scratch3_translate/index.js

@@ -1,7 +1,10 @@
 const ArgumentType = require('../../extension-support/argument-type');
 const BlockType = require('../../extension-support/block-type');
+const Cast = require('../../util/cast');
 const log = require('../../util/log');
 const nets = require('nets');
+const languageNames = require('scratch-translate-extension-languages');
+const formatMessage = require('format-message');
 
 // TODO: Change these to the correct icons.
 const blockIconURI = 'https://www.gstatic.com/images/icons/material/system/1x/translate_white_24dp.png';
@@ -20,17 +23,27 @@ const serverURL = 'https://translate-service.scratch.mit.edu/';
 const serverTimeoutMs = 10000; // 10 seconds (chosen arbitrarily).
 
 /**
- * Class for the translate-related block in Scratch 3.0
+ * Class for the translate block in Scratch 3.0.
  * @constructor
  */
 class Scratch3TranslateBlocks {
     constructor () {
         /**
-         * List of supported language name and language code pairs.
+         * Language code of the viewer, based on their locale.
+         * @type {string}
+         * @private
+         */
+        this._viewerLanguageCode = this.getViewerLanguageCode();
+
+        /**
+         * List of supported language name and language code pairs, for use in the block menu.
          * @type {Array.<object.<string, string>>}
          * @private
          */
-        this._supportedLanguages = null;
+        this._supportedLanguages = languageNames.menuMap[this._viewerLanguageCode].map(entry => {
+            const obj = {text: entry.name, value: entry.code};
+            return obj;
+        });
 
         /**
          * The result from the most recent translation.
@@ -52,10 +65,6 @@ class Scratch3TranslateBlocks {
          * @private
          */
         this._lastTextTranslated = '';
-
-
-        // Kick off the request to get supported languages from the server.
-        this._getSupportedLanguagesFromServer();
     }
 
     /**
@@ -66,61 +75,6 @@ class Scratch3TranslateBlocks {
         return 'Scratch.translate';
     }
 
-    /**
-     * Makes a request to the translate server to fetch a list of langauges
-     * to fill in the block's language menu.
-     * @private
-     */
-    _getSupportedLanguagesFromServer () {
-        // TODO: Pass through project language instead of English.
-        const url = `${serverURL}supported?language=en`;
-        const langPromise = new Promise(resolve => {
-            nets({
-                method: 'GET',
-                url: url,
-                timeout: serverTimeoutMs,
-                json: {}
-            }, (err, res, body) => {
-                // If we fail to fetch languages, just return an empty list.
-                // TODO: Figure out a reasonable time to retry. Otherwise,
-                // the list stays empty until the extension is reloaded.
-                if (err) {
-                    log.warn(`error fetching language list: ${err}`);
-                    resolve(null);
-                    return;
-                }
-                const langs = body.result;
-                if (!langs) {
-                    log.warn('No result in langauge response.');
-                    resolve(null);
-                    return;
-                }
-                resolve(langs);
-            });
-        });
-        langPromise.then(langs => {
-            if (langs) {
-                this._supportedLanguages =
-                      langs.map(entry => {
-                          const obj = {text: entry.name, value: entry.code};
-                          return obj;
-                      });
-            }
-        });
-    }
-
-    /**
-     * List of supported language name and language code pairs.
-     * @return {Array.<object.<string, string>>} The list of language name/code pairs.
-     * @private
-     */
-    _buildLanguageMenu () {
-        if (!this._supportedLanguages) {
-            return [{}];
-        }
-        return this._supportedLanguages;
-    }
-
     /**
      * @returns {object} metadata for this extension and its blocks.
      */
@@ -142,18 +96,61 @@ class Scratch3TranslateBlocks {
                         },
                         LANGUAGE: {
                             type: ArgumentType.STRING,
-                            menu: 'languages'
-
+                            menu: 'languages',
+                            defaultValue: this._viewerLanguageCode
                         }
                     }
                 }
             ],
             menus: {
-                languages: '_buildLanguageMenu'
+                languages: this._supportedLanguages
             }
         };
     }
-     
+
+
+    /**
+     * Get the viewer's language code.
+     * @return {string} the language code.
+     */
+    getViewerLanguageCode () {
+        const locale = formatMessage.setup().locale;
+        const viewerLanguages = [locale].concat(navigator.languages);
+        const languageKeys = Object.keys(languageNames.menuMap);
+        // Return the first entry in viewerLanguages that matches
+        // one of the available language keys.
+        const languageCode = viewerLanguages.reduce((acc, lang) => {
+            if (acc) {
+                return acc;
+            }
+            if (languageKeys.indexOf(lang) > -1) {
+                return lang;
+            }
+            return acc;
+        }, '') || 'en';
+        return languageCode;
+    }
+
+    /**
+     * Get a language code from a block argument. The arg can be a language code
+     * or a language name, written in any language.
+     * @param  {object} arg A block argument.
+     * @return {string} A language code.
+     */
+    getLanguageCodeFromArg (arg) {
+        const languageArg = Cast.toString(arg).toLowerCase();
+        // Check if the arg matches a language code in the menu.
+        if (languageNames.menuMap.hasOwnProperty(languageArg)) {
+            return languageArg;
+        }
+        // Check for a dropped-in language name, and convert to a language code.
+        if (languageNames.nameMap.hasOwnProperty(languageArg)) {
+            return languageNames.nameMap[languageArg];
+        }
+        // Default to English.
+        return 'en';
+    }
+
     /**
      * Translates the text in the translate block to the language specified in the menu.
      * @param {object} args - the block arguments.
@@ -166,13 +163,9 @@ class Scratch3TranslateBlocks {
             return this._translateResult;
         }
 
-        // TODO: Set default to project language instead of english?
-        let urlBase = `${serverURL}translate?language=`;
-        let lang = 'en';
-        if (args.LANGUAGE) {
-            lang = args.LANGUAGE;
-        }
+        const lang = this.getLanguageCodeFromArg(args.LANGUAGE);
 
+        let urlBase = `${serverURL}translate?language=`;
         urlBase += lang;
         urlBase += '&text=';
         urlBase += encodeURIComponent(args.WORDS);