anotherim/src/main/java/eu/siacs/conversations/utils/Compatibility.java

package eu.siacs.conversations.utils;

import android.content.Context;
import android.content.SharedPreferences;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager;
import android.os.Build;
import android.preference.Preference;
import android.preference.PreferenceCategory;
import android.preference.PreferenceManager;
import android.support.annotation.BoolRes;
import android.support.v4.content.ContextCompat;

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

import eu.siacs.conversations.R;
import eu.siacs.conversations.ui.SettingsActivity;
import eu.siacs.conversations.ui.SettingsFragment;

public class Compatibility {

    private static final List<String> UNUSED_SETTINGS_POST_TWENTYSIX = Arrays.asList(
            "led",
            "notification_ringtone",
            "notification_headsup",
            "vibrate_on_notification");
    private static final List<String> UNUESD_SETTINGS_PRE_TWENTYSIX = Collections.singletonList("more_notification_settings");


    public static boolean hasStoragePermission(Context context) {
        return Build.VERSION.SDK_INT < Build.VERSION_CODES.M || ContextCompat.checkSelfPermission(context, android.Manifest.permission.WRITE_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED;
    }

    public static boolean runsTwentySix() {
        return Build.VERSION.SDK_INT >= Build.VERSION_CODES.O;
    }

    public static boolean twentyTwo() {
        return Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP_MR1;
    }

    private static boolean getBooleanPreference(Context context, String name, @BoolRes int res) {
        return getPreferences(context).getBoolean(name, context.getResources().getBoolean(res));
    }

    private static SharedPreferences getPreferences(final Context context) {
        return PreferenceManager.getDefaultSharedPreferences(context);
    }

    private static boolean targetsTwentySix(Context context) {
        try {
            final PackageManager packageManager = context.getPackageManager();
            final ApplicationInfo applicationInfo = packageManager.getApplicationInfo(context.getPackageName(), 0);
            return applicationInfo == null || applicationInfo.targetSdkVersion >= 26;
        } catch (PackageManager.NameNotFoundException e) {
            return true; //when in doubt…
        }
    }

    public static boolean runsAndTargetsTwentySix(Context context) {
        return runsTwentySix() && targetsTwentySix(context);
    }

    public static boolean keepForegroundService(Context context) {
        return runsAndTargetsTwentySix(context) || getBooleanPreference(context, SettingsActivity.KEEP_FOREGROUND_SERVICE, R.bool.enable_foreground_service);
    }

    public static void removeUnusedPreferences(SettingsFragment settingsFragment) {
        List<PreferenceCategory> categories = Arrays.asList(
                (PreferenceCategory) settingsFragment.findPreference("notification_category"),
                (PreferenceCategory) settingsFragment.findPreference("other_expert_category"));
        for (String key : (runsTwentySix() ? UNUSED_SETTINGS_POST_TWENTYSIX : UNUESD_SETTINGS_PRE_TWENTYSIX)) {
            Preference preference = settingsFragment.findPreference(key);
            if (preference != null) {
                for (PreferenceCategory category : categories) {
                    if (category != null) {
                        category.removePreference(preference);
                    }
                }
            }
        }
        if (Compatibility.runsTwentySix()) {
            if (targetsTwentySix(settingsFragment.getContext())) {
                Preference preference = settingsFragment.findPreference(SettingsActivity.KEEP_FOREGROUND_SERVICE);
                if (preference != null) {
                    for (PreferenceCategory category : categories) {
                        if (category != null) {
                            category.removePreference(preference);
                        }
                    }
                }
            }
        }
    }
}