/*
 * Copyright (C) 2022 The Android Open Source Project
 *
 * 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 com.android.settings.applications;

import android.annotation.NonNull;
import android.app.ActivityManager;
import android.app.LocaleConfig;
import android.content.Context;
import android.content.Intent;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.content.pm.ResolveInfo;
import android.os.LocaleList;
import android.util.FeatureFlagUtils;
import android.util.Log;

import com.android.settings.R;

import java.util.List;

/** This class provides methods that help dealing with per app locale. */
public class AppLocaleUtil {
    private static final String TAG = AppLocaleUtil.class.getSimpleName();

    public static final Intent LAUNCHER_ENTRY_INTENT =
            new Intent(Intent.ACTION_MAIN).addCategory(Intent.CATEGORY_LAUNCHER);

    /**
     * Decides the UI display of per app locale.
     */
    public static boolean canDisplayLocaleUi(
            @NonNull Context context,
            @NonNull String packageName,
            @NonNull List<ResolveInfo> infos) {
        boolean isDisallowedPackage = isDisallowedPackage(context, packageName);
        boolean hasLauncherEntry = hasLauncherEntry(packageName, infos);
        boolean isSignedWithPlatformKey = isSignedWithPlatformKey(context, packageName);
        boolean isAppLocaleSupported = isAppLocaleSupported(context, packageName);
        Log.i(TAG, "Can display preference - [" + packageName + "] :"
                + " isDisallowedPackage : " + isDisallowedPackage
                + " / isSignedWithPlatformKey : " + isSignedWithPlatformKey
                + " / hasLauncherEntry : " + hasLauncherEntry
                + " / isAppLocaleSupported : " + isAppLocaleSupported);

        return !isDisallowedPackage
                && !isSignedWithPlatformKey
                && hasLauncherEntry
                && isAppLocaleSupported;
    }

    private static boolean isDisallowedPackage(Context context, String packageName) {
        final String[] disallowedPackages = context.getResources().getStringArray(
                R.array.config_disallowed_app_localeChange_packages);
        for (String disallowedPackage : disallowedPackages) {
            if (packageName.equals(disallowedPackage)) {
                return true;
            }
        }
        return false;
    }

    private static boolean isSignedWithPlatformKey(Context context, String packageName) {
        PackageInfo packageInfo = null;
        PackageManager packageManager = context.getPackageManager();
        ActivityManager activityManager = context.getSystemService(ActivityManager.class);
        try {
            packageInfo = packageManager.getPackageInfoAsUser(
                    packageName, /* flags= */ 0,
                    activityManager.getCurrentUser());
        } catch (PackageManager.NameNotFoundException ex) {
            Log.e(TAG, "package not found: " + packageName);
        }
        if (packageInfo == null) {
            return false;
        }
        return packageInfo.applicationInfo.isSignedWithPlatformKey();
    }

    private static boolean hasLauncherEntry(String packageName, List<ResolveInfo> infos) {
        return infos.stream()
                .anyMatch(info -> info.activityInfo.packageName.equals(packageName));
    }

    /**
     * Check the function of per app language is supported by current application.
     */
    public static boolean isAppLocaleSupported(Context context, String packageName) {
        if (getPackageLocales(context, packageName) != null) {
            return true;
        }

        if (FeatureFlagUtils.isEnabled(
                context, FeatureFlagUtils.SETTINGS_APP_LOCALE_OPT_IN_ENABLED)) {
            return false;
        }

        return getAssetLocales(context, packageName).length > 0;
    }

    /**
     * Get locales fron AssetManager.
     */
    public static String[] getAssetLocales(Context context, String packageName) {
        try {
            PackageManager packageManager = context.getPackageManager();
            String[] locales = packageManager.getResourcesForApplication(
                    packageManager.getPackageInfo(packageName, PackageManager.MATCH_ALL)
                            .applicationInfo).getAssets().getNonSystemLocales();
            if (locales == null) {
                Log.i(TAG, "[" + packageName + "] locales are null.");
            }
            if (locales.length <= 0) {
                Log.i(TAG, "[" + packageName + "] locales length is 0.");
                return new String[0];
            }
            String locale = locales[0];
            Log.i(TAG, "First asset locale - [" + packageName + "] " + locale);
            return locales;
        } catch (PackageManager.NameNotFoundException e) {
            Log.w(TAG, "Can not found the package name : " + packageName + " / " + e);
        }
        return new String[0];
    }

    /**
     * Get locales from LocaleConfig.
     */
    public static LocaleList getPackageLocales(Context context, String packageName) {
        try {
            LocaleConfig localeConfig =
                    new LocaleConfig(context.createPackageContext(packageName, 0));
            if (localeConfig.getStatus() == LocaleConfig.STATUS_SUCCESS) {
                return localeConfig.getSupportedLocales();
            }
        } catch (PackageManager.NameNotFoundException e) {
            Log.w(TAG, "Can not found the package name : " + packageName + " / " + e);
        }
        return null;
    }
}