/**
* Copyright (C) 2012-2014 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package ninja.i18n;
import java.util.Locale;
import ninja.Context;
import ninja.Cookie;
import ninja.Result;
import ninja.utils.NinjaConstant;
import ninja.utils.NinjaProperties;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.google.common.base.Optional;
import com.google.common.base.Splitter;
import com.google.inject.Inject;
import com.google.inject.Singleton;
@Singleton
public class LangImpl implements Lang {
private static Logger logger = LoggerFactory.getLogger(LangImpl.class);
private final String applicationCookiePrefix;
private final int TEN_YEARS = 60*60*24*365*10;
private final NinjaProperties ninjaProperties;
private final String DEFAULT_LANGUAGE;
@Inject
public LangImpl(NinjaProperties ninjaProperties) {
this.ninjaProperties = ninjaProperties;
this.applicationCookiePrefix = ninjaProperties
.getOrDie(NinjaConstant.applicationCookiePrefix);
this.DEFAULT_LANGUAGE = getDefaultLanguage(this.ninjaProperties);
}
@Override
public void clearLanguage(Result result) {
Cookie defaultLangCookie = generateNinjaLanguageCookie();
result.unsetCookie(defaultLangCookie.getName());
}
@Override
public Result setLanguage(String locale, Result result) {
Cookie defaultLangCookie = generateNinjaLanguageCookie();
Cookie cookie = Cookie.builder(defaultLangCookie).setValue(locale).build();
result.addCookie(cookie);
return result;
}
@Override
public Optional<String> getLanguage(Context context, Optional<Result> result) {
Cookie defaultCookie = generateNinjaLanguageCookie();
// Step 1: Determine language from result.
// Result always has priority over context and will overwrite context.
if (result.isPresent()) {
Cookie cookie = result.get().getCookie(defaultCookie.getName());
if (cookie != null) {
if (cookie.getValue() != null
&& !cookie.getValue().isEmpty()) {
//forced language is:
return Optional.of(cookie.getValue());
}
}
}
// Step 2 => we did not find the language in the result
// We try to determine it from the context.
Cookie cookie = context.getCookie(defaultCookie.getName());
if (cookie != null) {
if (cookie.getValue() != null
&& !cookie.getValue().isEmpty()) {
//forced language is:
return Optional.of(cookie.getValue());
}
}
// Step 3: Determine language from Accept-Language header.
String acceptLanguage = context.getAcceptLanguage();
if (acceptLanguage == null) {
return Optional.absent();
}
// Check if we get a registered mapping for the language input string.
// At that point the language may be either language-country or only country.
// extract multiple languages from Accept-Language header
Iterable<String> languages = Splitter.on(",").trimResults().split(acceptLanguage);
for (String language: languages){
// Ignore the relative quality factor in Accept-Language header
if (language.contains(";")){
language = language.split(";")[0];
return Optional.of(language);
} else {
return Optional.of(language);
}
}
return Optional.absent();
}
/**
* Retrieves the language cookie or generates one with a very long max age (ten years).
*
* @param context
* @return The cookie
*/
private Cookie generateNinjaLanguageCookie() {
Cookie cookie = Cookie.builder(applicationCookiePrefix
+ ninja.utils.NinjaConstant.LANG_COOKIE_SUFFIX, "")
.setMaxAge(TEN_YEARS).build();
return cookie;
}
@Override
public boolean isLanguageDirectlySupportedByThisApplication(String language) {
String applicationLanguages = ninjaProperties.get(NinjaConstant.applicationLanguages);
Iterable<String> languages = Splitter.on(",").trimResults().split(applicationLanguages);
for (String applicationLanguage : languages) {
if (applicationLanguage.equals(language)) {
return true;
}
}
return false;
}
@Override
public Locale getLocaleFromStringOrDefault(Optional<String> language) {
if (language.isPresent()) {
return Locale.forLanguageTag(language.get());
} else {
return Locale.forLanguageTag(DEFAULT_LANGUAGE);
}
}
String getDefaultLanguage(NinjaProperties ninjaProperties) {
String [] applicationLanguages
= ninjaProperties.getStringArray(NinjaConstant.applicationLanguages);
if (applicationLanguages == null || applicationLanguages.length == 0) {
String EXCEPTION_TEXT =
"Can not retrieve application languages from ninjaProperties."
+ " Did you forget to define at least one language in your application.conf file?"
+ " For instance 'application.languages=en' makes 'en' your default language.";
throw new IllegalStateException(EXCEPTION_TEXT);
}
// by convention the first language is the default language
String defaultLanguage = applicationLanguages[0];
return defaultLanguage;
}
}