LanguageMapper.java

/*
 * Copyright (C) 2017 Stichting Akvo (Akvo Foundation)
 *
 * This file is part of Akvo Flow.
 *
 * Akvo Flow is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Akvo Flow is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Akvo Flow.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

package org.akvo.flow.ui.model;

import android.content.Context;
import android.content.res.Resources;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.text.TextUtils;

import org.akvo.flow.R;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Set;

public class LanguageMapper {

    private final Context context;

    public LanguageMapper(Context context) {
        this.context = context;
    }

    @NonNull
    public List<Language> transform(@Nullable String[] languageCodesSelected,
            @Nullable Set<String> languageCodesAvailable) {
        if (languageCodesSelected == null || languageCodesAvailable == null) {
            return Collections.EMPTY_LIST;
        }
        List<Language> languages = new ArrayList<>(languageCodesAvailable.size());
        for (String language : languageCodesAvailable) {
            Language transformed = transform(language, languageCodesSelected);
            if (transformed != null) {
                languages.add(transformed);
            }
        }
        return languages;
    }

    @Nullable
    private Language transform(@Nullable String languageCode,
            @NonNull String[] languageCodesSelected) {
        if (TextUtils.isEmpty(languageCode)) {
            return null;
        }
        boolean selected = Arrays.asList(languageCodesSelected).contains(languageCode);
        Resources res = context.getResources();
        String[] languageCodes = res.getStringArray(R.array.alllanguagecodes);
        String[] languages = res.getStringArray(R.array.alllanguages);
        /**
         * This presupposes that both arrays languages and language codes have the same order
         * and contain the same languages
         */
        int languagePosition = Arrays.asList(languageCodes).indexOf(languageCode);
        if (languagePosition < 0 || languagePosition >= languages.length) {
            return null;
        }
        String languageName = languages[languagePosition];
        return new Language(languageCode, languageName, selected);
    }
}