1 /*
2  * Copyright (C) 2011 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License"); you may not
5  * use this file except in compliance with the License. You may obtain a copy of
6  * the License at
7  *
8  * http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
12  * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
13  * License for the specific language governing permissions and limitations under
14  * the License.
15  */
16 package android.speech.tts;
17 
18 import static android.provider.Settings.Secure.getString;
19 
20 import android.annotation.NonNull;
21 import android.compat.annotation.UnsupportedAppUsage;
22 import android.content.Context;
23 import android.content.Intent;
24 import android.content.pm.ApplicationInfo;
25 import android.content.pm.PackageManager;
26 import android.content.pm.PackageManager.NameNotFoundException;
27 import android.content.pm.ResolveInfo;
28 import android.content.pm.ServiceInfo;
29 import android.content.res.Resources;
30 import android.content.res.TypedArray;
31 import android.content.res.XmlResourceParser;
32 import android.provider.Settings;
33 import android.speech.tts.TextToSpeech.Engine;
34 import android.speech.tts.TextToSpeech.EngineInfo;
35 import android.text.TextUtils;
36 import android.util.AttributeSet;
37 import android.util.Log;
38 import android.util.Xml;
39 
40 import org.xmlpull.v1.XmlPullParserException;
41 
42 import java.io.IOException;
43 import java.util.ArrayList;
44 import java.util.Collections;
45 import java.util.Comparator;
46 import java.util.HashMap;
47 import java.util.List;
48 import java.util.Locale;
49 import java.util.Map;
50 import java.util.MissingResourceException;
51 
52 /**
53  * Support class for querying the list of available engines
54  * on the device and deciding which one to use etc.
55  *
56  * Comments in this class the use the shorthand "system engines" for engines that
57  * are a part of the system image.
58  *
59  * This class is thread-safe/
60  *
61  * @hide
62  */
63 public class TtsEngines {
64     private static final String TAG = "TtsEngines";
65     private static final boolean DBG = false;
66 
67     /** Locale delimiter used by the old-style 3 char locale string format (like "eng-usa") */
68     private static final String LOCALE_DELIMITER_OLD = "-";
69 
70     /** Locale delimiter used by the new-style locale string format (Locale.toString() results,
71      * like "en_US") */
72     private static final String LOCALE_DELIMITER_NEW = "_";
73 
74     private final Context mContext;
75 
76     /** Mapping of various language strings to the normalized Locale form */
77     private static final Map<String, String> sNormalizeLanguage;
78 
79     /** Mapping of various country strings to the normalized Locale form */
80     private static final Map<String, String> sNormalizeCountry;
81 
82     // Populate the sNormalize* maps
83     static {
84         HashMap<String, String> normalizeLanguage = new HashMap<String, String>();
85         for (String language : Locale.getISOLanguages()) {
86             try {
normalizeLanguage.put(new Locale(language).getISO3Language(), language)87                 normalizeLanguage.put(new Locale(language).getISO3Language(), language);
88             } catch (MissingResourceException e) {
89                 continue;
90             }
91         }
92         sNormalizeLanguage = Collections.unmodifiableMap(normalizeLanguage);
93 
94         HashMap<String, String> normalizeCountry = new HashMap<String, String>();
95         for (String country : Locale.getISOCountries()) {
96             try {
normalizeCountry.put(new Locale("", country).getISO3Country(), country)97                 normalizeCountry.put(new Locale("", country).getISO3Country(), country);
98             } catch (MissingResourceException e) {
99                 continue;
100             }
101         }
102         sNormalizeCountry = Collections.unmodifiableMap(normalizeCountry);
103     }
104 
105     @UnsupportedAppUsage
TtsEngines(Context ctx)106     public TtsEngines(Context ctx) {
107         mContext = ctx;
108     }
109 
110     /**
111      * @return the default TTS engine. If the user has set a default, and the engine
112      *         is available on the device, the default is returned. Otherwise,
113      *         the highest ranked engine is returned as per {@link EngineInfoComparator}.
114      */
getDefaultEngine()115     public String getDefaultEngine() {
116         String engine = getString(mContext.getContentResolver(),
117                 Settings.Secure.TTS_DEFAULT_SYNTH);
118         return isEngineInstalled(engine) ? engine : getHighestRankedEngineName();
119     }
120 
121     /**
122      * @return the package name of the highest ranked system engine, {@code null}
123      *         if no TTS engines were present in the system image.
124      */
getHighestRankedEngineName()125     public String getHighestRankedEngineName() {
126         final List<EngineInfo> engines = getEngines();
127 
128         if (engines.size() > 0 && engines.get(0).system) {
129             return engines.get(0).name;
130         }
131 
132         return null;
133     }
134 
135     /**
136      * Returns the engine info for a given engine name. Note that engines are
137      * identified by their package name.
138      */
getEngineInfo(String packageName)139     public EngineInfo getEngineInfo(String packageName) {
140         PackageManager pm = mContext.getPackageManager();
141         Intent intent = new Intent(Engine.INTENT_ACTION_TTS_SERVICE);
142         intent.setPackage(packageName);
143         List<ResolveInfo> resolveInfos = pm.queryIntentServices(intent,
144                 PackageManager.MATCH_DEFAULT_ONLY);
145         // Note that the current API allows only one engine per
146         // package name. Since the "engine name" is the same as
147         // the package name.
148         if (resolveInfos != null && resolveInfos.size() == 1) {
149             return getEngineInfo(resolveInfos.get(0), pm);
150         }
151 
152         return null;
153     }
154 
155     /**
156      * Gets a list of all installed TTS engines.
157      *
158      * @return A list of engine info objects. The list can be empty, but never {@code null}.
159      */
160     @UnsupportedAppUsage
getEngines()161     public List<EngineInfo> getEngines() {
162         PackageManager pm = mContext.getPackageManager();
163         Intent intent = new Intent(Engine.INTENT_ACTION_TTS_SERVICE);
164         List<ResolveInfo> resolveInfos =
165                 pm.queryIntentServices(intent, PackageManager.MATCH_DEFAULT_ONLY);
166         if (resolveInfos == null) return Collections.emptyList();
167 
168         List<EngineInfo> engines = new ArrayList<EngineInfo>(resolveInfos.size());
169 
170         for (ResolveInfo resolveInfo : resolveInfos) {
171             EngineInfo engine = getEngineInfo(resolveInfo, pm);
172             if (engine != null) {
173                 engines.add(engine);
174             }
175         }
176         Collections.sort(engines, EngineInfoComparator.INSTANCE);
177 
178         return engines;
179     }
180 
isSystemEngine(ServiceInfo info)181     private boolean isSystemEngine(ServiceInfo info) {
182         final ApplicationInfo appInfo = info.applicationInfo;
183         return appInfo != null && (appInfo.flags & ApplicationInfo.FLAG_SYSTEM) != 0;
184     }
185 
186     /**
187      * @return true if a given engine is installed on the system.
188      */
isEngineInstalled(String engine)189     public boolean isEngineInstalled(String engine) {
190         if (engine == null) {
191             return false;
192         }
193 
194         return getEngineInfo(engine) != null;
195     }
196 
197     /**
198      * @return an intent that can launch the settings activity for a given tts engine.
199      */
200     @UnsupportedAppUsage
getSettingsIntent(String engine)201     public Intent getSettingsIntent(String engine) {
202         PackageManager pm = mContext.getPackageManager();
203         Intent intent = new Intent(Engine.INTENT_ACTION_TTS_SERVICE);
204         intent.setPackage(engine);
205         List<ResolveInfo> resolveInfos = pm.queryIntentServices(intent,
206                 PackageManager.MATCH_DEFAULT_ONLY | PackageManager.GET_META_DATA);
207         // Note that the current API allows only one engine per
208         // package name. Since the "engine name" is the same as
209         // the package name.
210         if (resolveInfos != null && resolveInfos.size() == 1) {
211             ServiceInfo service = resolveInfos.get(0).serviceInfo;
212             if (service != null) {
213                 final String settings = settingsActivityFromServiceInfo(service, pm);
214                 if (settings != null) {
215                     Intent i = new Intent();
216                     i.setClassName(engine, settings);
217                     return i;
218                 }
219             }
220         }
221 
222         return null;
223     }
224 
225     /**
226      * The name of the XML tag that text to speech engines must use to
227      * declare their meta data.
228      *
229      * {@link com.android.internal.R.styleable#TextToSpeechEngine}
230      */
231     private static final String XML_TAG_NAME = "tts-engine";
232 
settingsActivityFromServiceInfo(ServiceInfo si, PackageManager pm)233     private String settingsActivityFromServiceInfo(ServiceInfo si, PackageManager pm) {
234         XmlResourceParser parser = null;
235         try {
236             parser = si.loadXmlMetaData(pm, TextToSpeech.Engine.SERVICE_META_DATA);
237             if (parser == null) {
238                 Log.w(TAG, "No meta-data found for :" + si);
239                 return null;
240             }
241 
242             final Resources res = pm.getResourcesForApplication(si.applicationInfo);
243 
244             int type;
245             while ((type = parser.next()) != XmlResourceParser.END_DOCUMENT) {
246                 if (type == XmlResourceParser.START_TAG) {
247                     if (!XML_TAG_NAME.equals(parser.getName())) {
248                         Log.w(TAG, "Package " + si + " uses unknown tag :"
249                                 + parser.getName());
250                         return null;
251                     }
252 
253                     final AttributeSet attrs = Xml.asAttributeSet(parser);
254                     final TypedArray array = res.obtainAttributes(attrs,
255                             com.android.internal.R.styleable.TextToSpeechEngine);
256                     final String settings = array.getString(
257                             com.android.internal.R.styleable.TextToSpeechEngine_settingsActivity);
258                     array.recycle();
259 
260                     return settings;
261                 }
262             }
263 
264             return null;
265         } catch (NameNotFoundException e) {
266             Log.w(TAG, "Could not load resources for : " + si);
267             return null;
268         } catch (XmlPullParserException e) {
269             Log.w(TAG, "Error parsing metadata for " + si + ":" + e);
270             return null;
271         } catch (IOException e) {
272             Log.w(TAG, "Error parsing metadata for " + si + ":" + e);
273             return null;
274         } finally {
275             if (parser != null) {
276                 parser.close();
277             }
278         }
279     }
280 
getEngineInfo(ResolveInfo resolve, PackageManager pm)281     private EngineInfo getEngineInfo(ResolveInfo resolve, PackageManager pm) {
282         ServiceInfo service = resolve.serviceInfo;
283         if (service != null) {
284             EngineInfo engine = new EngineInfo();
285             // Using just the package name isn't great, since it disallows having
286             // multiple engines in the same package, but that's what the existing API does.
287             engine.name = service.packageName;
288             CharSequence label = service.loadLabel(pm);
289             engine.label = TextUtils.isEmpty(label) ? engine.name : label.toString();
290             engine.icon = service.getIconResource();
291             engine.priority = resolve.priority;
292             engine.system = isSystemEngine(service);
293             return engine;
294         }
295 
296         return null;
297     }
298 
299     private static class EngineInfoComparator implements Comparator<EngineInfo> {
EngineInfoComparator()300         private EngineInfoComparator() { }
301 
302         static EngineInfoComparator INSTANCE = new EngineInfoComparator();
303 
304         /**
305          * Engines that are a part of the system image are always lesser
306          * than those that are not. Within system engines / non system engines
307          * the engines are sorted in order of their declared priority.
308          */
309         @Override
compare(EngineInfo lhs, EngineInfo rhs)310         public int compare(EngineInfo lhs, EngineInfo rhs) {
311             if (lhs.system && !rhs.system) {
312                 return -1;
313             } else if (rhs.system && !lhs.system) {
314                 return 1;
315             } else {
316                 // Either both system engines, or both non system
317                 // engines.
318                 //
319                 // Note, this isn't a typo. Higher priority numbers imply
320                 // higher priority, but are "lower" in the sort order.
321                 return rhs.priority - lhs.priority;
322             }
323         }
324     }
325 
326     /**
327      * Returns the default locale for a given TTS engine. Attempts to read the
328      * value from {@link Settings.Secure#TTS_DEFAULT_LOCALE}, failing which the
329      * default phone locale is returned.
330      *
331      * @param engineName the engine to return the locale for.
332      * @return the locale preference for this engine. Will be non null.
333      */
334     @UnsupportedAppUsage
getLocalePrefForEngine(String engineName)335     public Locale getLocalePrefForEngine(String engineName) {
336         return getLocalePrefForEngine(engineName,
337                 getString(mContext.getContentResolver(), Settings.Secure.TTS_DEFAULT_LOCALE));
338     }
339 
340     /**
341      * Returns the default locale for a given TTS engine from given settings string. */
getLocalePrefForEngine(String engineName, String prefValue)342     public Locale getLocalePrefForEngine(String engineName, String prefValue) {
343         String localeString = parseEnginePrefFromList(
344                 prefValue,
345                 engineName);
346 
347         if (TextUtils.isEmpty(localeString)) {
348             // The new style setting is unset, attempt to return the old style setting.
349             return Locale.getDefault();
350         }
351 
352         Locale result = parseLocaleString(localeString);
353         if (result == null) {
354             Log.w(TAG, "Failed to parse locale " + localeString + ", returning en_US instead");
355             result = Locale.US;
356         }
357 
358         if (DBG) Log.d(TAG, "getLocalePrefForEngine(" + engineName + ")= " + result);
359 
360         return result;
361     }
362 
363 
364     /**
365      * True if a given TTS engine uses the default phone locale as a default locale. Attempts to
366      * read the value from {@link Settings.Secure#TTS_DEFAULT_LOCALE}. If
367      * its  value is empty, this methods returns true.
368      *
369      * @param engineName the engine to return the locale for.
370      */
isLocaleSetToDefaultForEngine(String engineName)371     public boolean isLocaleSetToDefaultForEngine(String engineName) {
372         return TextUtils.isEmpty(parseEnginePrefFromList(
373                     getString(mContext.getContentResolver(), Settings.Secure.TTS_DEFAULT_LOCALE),
374                     engineName));
375     }
376 
377     /**
378      * Parses a locale encoded as a string, and tries its best to return a valid {@link Locale}
379      * object, even if the input string is encoded using the old-style 3 character format e.g.
380      * "deu-deu". At the end, we test if the resulting locale can return ISO3 language and
381      * country codes ({@link Locale#getISO3Language()} and {@link Locale#getISO3Country()}),
382      * if it fails to do so, we return null.
383      */
384     @UnsupportedAppUsage
parseLocaleString(String localeString)385     public Locale parseLocaleString(String localeString) {
386         String language = "", country = "", variant = "";
387         if (!TextUtils.isEmpty(localeString)) {
388             String[] split = localeString.split(
389                     "[" + LOCALE_DELIMITER_OLD + LOCALE_DELIMITER_NEW + "]");
390             language = split[0].toLowerCase();
391             if (split.length == 0) {
392                 Log.w(TAG, "Failed to convert " + localeString + " to a valid Locale object. Only" +
393                             " separators");
394                 return null;
395             }
396             if (split.length > 3) {
397                 Log.w(TAG, "Failed to convert " + localeString + " to a valid Locale object. Too" +
398                         " many separators");
399                 return null;
400             }
401             if (split.length >= 2) {
402                 country = split[1].toUpperCase();
403             }
404             if (split.length >= 3) {
405                 variant = split[2];
406             }
407 
408         }
409 
410         String normalizedLanguage = sNormalizeLanguage.get(language);
411         if (normalizedLanguage != null) {
412             language = normalizedLanguage;
413         }
414 
415         String normalizedCountry= sNormalizeCountry.get(country);
416         if (normalizedCountry != null) {
417             country = normalizedCountry;
418         }
419 
420         if (DBG) Log.d(TAG, "parseLocalePref(" + language + "," + country +
421                 "," + variant +")");
422 
423         Locale result = new Locale(language, country, variant);
424         try {
425             result.getISO3Language();
426             result.getISO3Country();
427             return result;
428         } catch(MissingResourceException e) {
429             Log.w(TAG, "Failed to convert " + localeString + " to a valid Locale object.");
430             return null;
431         }
432     }
433 
434     /**
435      * This method tries its best to return a valid {@link Locale} object from the TTS-specific
436      * Locale input (returned by {@link TextToSpeech#getLanguage}
437      * and {@link TextToSpeech#getDefaultLanguage}). A TTS Locale language field contains
438      * a three-letter ISO 639-2/T code (where a proper Locale would use a two-letter ISO 639-1
439      * code), and the country field contains a three-letter ISO 3166 country code (where a proper
440      * Locale would use a two-letter ISO 3166-1 code).
441      *
442      * This method tries to convert three-letter language and country codes into their two-letter
443      * equivalents. If it fails to do so, it keeps the value from the TTS locale.
444      */
445     @UnsupportedAppUsage
normalizeTTSLocale(Locale ttsLocale)446     public static Locale normalizeTTSLocale(Locale ttsLocale) {
447         String language = ttsLocale.getLanguage();
448         if (!TextUtils.isEmpty(language)) {
449             String normalizedLanguage = sNormalizeLanguage.get(language);
450             if (normalizedLanguage != null) {
451                 language = normalizedLanguage;
452             }
453         }
454 
455         String country = ttsLocale.getCountry();
456         if (!TextUtils.isEmpty(country)) {
457             String normalizedCountry= sNormalizeCountry.get(country);
458             if (normalizedCountry != null) {
459                 country = normalizedCountry;
460             }
461         }
462         return new Locale(language, country, ttsLocale.getVariant());
463     }
464 
465     /**
466      * Return the old-style string form of the locale. It consists of 3 letter codes:
467      * <ul>
468      *   <li>"ISO 639-2/T language code" if the locale has no country entry</li>
469      *   <li> "ISO 639-2/T language code{@link #LOCALE_DELIMITER}ISO 3166 country code"
470      *     if the locale has no variant entry</li>
471      *   <li> "ISO 639-2/T language code{@link #LOCALE_DELIMITER}ISO 3166 country
472      *     code{@link #LOCALE_DELIMITER}variant" if the locale has a variant entry</li>
473      * </ul>
474      * If we fail to generate those codes using {@link Locale#getISO3Country()} and
475      * {@link Locale#getISO3Language()}, then we return new String[]{"eng","USA",""};
476      */
toOldLocaleStringFormat(Locale locale)477     static public String[] toOldLocaleStringFormat(Locale locale) {
478         String[] ret = new String[]{"","",""};
479         try {
480             // Note that the default locale might have an empty variant
481             // or language.
482             ret[0] = locale.getISO3Language();
483             ret[1] = locale.getISO3Country();
484             ret[2] = locale.getVariant();
485 
486             return ret;
487         } catch (MissingResourceException e) {
488             // Default locale does not have a ISO 3166 and/or ISO 639-2/T codes. Return the
489             // default "eng-usa" (that would be the result of Locale.getDefault() == Locale.US).
490             return new String[]{"eng","USA",""};
491         }
492     }
493 
494     /**
495      * Parses a comma separated list of engine locale preferences. The list is of the
496      * form {@code "engine_name_1:locale_1,engine_name_2:locale2"} and so on and
497      * so forth. Returns null if the list is empty, malformed or if there is no engine
498      * specific preference in the list.
499      */
parseEnginePrefFromList(String prefValue, String engineName)500     private static String parseEnginePrefFromList(String prefValue, String engineName) {
501         if (TextUtils.isEmpty(prefValue)) {
502             return null;
503         }
504 
505         String[] prefValues = prefValue.split(",");
506 
507         for (String value : prefValues) {
508             final int delimiter = value.indexOf(':');
509             if (delimiter > 0) {
510                 if (engineName.equals(value.substring(0, delimiter))) {
511                     return value.substring(delimiter + 1);
512                 }
513             }
514         }
515 
516         return null;
517     }
518 
519     /**
520      * Serialize the locale to a string and store it as a default locale for the given engine. If
521      * the passed locale is null, an empty string will be serialized; that empty string, when
522      * read back, will evaluate to {@link Locale#getDefault()}.
523      */
524     @UnsupportedAppUsage
updateLocalePrefForEngine( @onNull String engineName, Locale newLocale)525     public synchronized void updateLocalePrefForEngine(
526             @NonNull String engineName, Locale newLocale) {
527         final String prefList = Settings.Secure.getString(mContext.getContentResolver(),
528                 Settings.Secure.TTS_DEFAULT_LOCALE);
529         if (DBG) {
530             Log.d(TAG, "updateLocalePrefForEngine(" + engineName + ", " + newLocale +
531                     "), originally: " + prefList);
532         }
533 
534         final String newPrefList = updateValueInCommaSeparatedList(prefList,
535                 engineName, (newLocale != null) ? newLocale.toString() : "");
536 
537         if (DBG) Log.d(TAG, "updateLocalePrefForEngine(), writing: " + newPrefList.toString());
538 
539         Settings.Secure.putString(mContext.getContentResolver(),
540                 Settings.Secure.TTS_DEFAULT_LOCALE, newPrefList.toString());
541     }
542 
543     /**
544      * Updates the value for a given key in a comma separated list of key value pairs,
545      * each of which are delimited by a colon. If no value exists for the given key,
546      * the kay value pair are appended to the end of the list.
547      */
updateValueInCommaSeparatedList(String list, String key, String newValue)548     private String updateValueInCommaSeparatedList(String list, String key,
549             String newValue) {
550         StringBuilder newPrefList = new StringBuilder();
551         if (TextUtils.isEmpty(list)) {
552             // If empty, create a new list with a single entry.
553             newPrefList.append(key).append(':').append(newValue);
554         } else {
555             String[] prefValues = list.split(",");
556             // Whether this is the first iteration in the loop.
557             boolean first = true;
558             // Whether we found the given key.
559             boolean found = false;
560             for (String value : prefValues) {
561                 final int delimiter = value.indexOf(':');
562                 if (delimiter > 0) {
563                     if (key.equals(value.substring(0, delimiter))) {
564                         if (first) {
565                             first = false;
566                         } else {
567                             newPrefList.append(',');
568                         }
569                         found = true;
570                         newPrefList.append(key).append(':').append(newValue);
571                     } else {
572                         if (first) {
573                             first = false;
574                         } else {
575                             newPrefList.append(',');
576                         }
577                         // Copy across the entire key + value as is.
578                         newPrefList.append(value);
579                     }
580                 }
581             }
582 
583             if (!found) {
584                 // Not found, but the rest of the keys would have been copied
585                 // over already, so just append it to the end.
586                 newPrefList.append(',');
587                 newPrefList.append(key).append(':').append(newValue);
588             }
589         }
590 
591         return newPrefList.toString();
592     }
593 }
594