/*
 * Copyright (C) 2019 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.server.systemconfig;

import static org.junit.Assert.assertEquals;

import android.util.ArrayMap;
import android.util.ArraySet;
import android.util.Log;

import androidx.test.filters.SmallTest;
import androidx.test.runner.AndroidJUnit4;

import com.android.server.SystemConfig;

import org.junit.Before;
import org.junit.Rule;
import org.junit.Test;
import org.junit.rules.TemporaryFolder;
import org.junit.runner.RunWith;

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Arrays;
import java.util.Map;
import java.util.Scanner;
import java.util.Set;

/**
 * Tests for {@link SystemConfig}.
 *
 * Build/Install/Run:
 *  atest FrameworksServicesTests:SystemConfigTest
 */
@RunWith(AndroidJUnit4.class)
@SmallTest
public class SystemConfigTest {
    private static final String LOG_TAG = "SystemConfigTest";

    private SystemConfig mSysConfig;

    @Rule public TemporaryFolder mTemporaryFolder = new TemporaryFolder();

    @Before
    public void setUp() throws Exception {
        mSysConfig = new SystemConfigTestClass();
    }

    /**
     * Subclass of SystemConfig without running the constructor.
     */
    private class SystemConfigTestClass extends SystemConfig {
        SystemConfigTestClass() {
            super(false);
        }
    }

    /**
     * Tests that readPermissions works correctly for the tag: install-in-user-type
     */
    @Test
    public void testInstallInUserType() throws Exception {
        final String contents1 =
                  "<permissions>\n"
                + "    <install-in-user-type package=\"com.android.package1\">\n"
                + "        <install-in user-type=\"FULL\" />\n"
                + "        <install-in user-type=\"PROFILE\" />\n"
                + "    </install-in-user-type>\n"
                + "    <install-in-user-type package=\"com.android.package2\">\n"
                + "        <install-in user-type=\"FULL\" />\n"
                + "        <install-in user-type=\"PROFILE\" />\n"
                + "        <do-not-install-in user-type=\"GUEST\" />\n"
                + "    </install-in-user-type>\n"
                + "</permissions>";

        final String contents2 =
                  "<permissions>\n"
                + "    <install-in-user-type package=\"com.android.package2\">\n"
                + "        <install-in user-type=\"SYSTEM\" />\n"
                + "        <do-not-install-in user-type=\"PROFILE\" />\n"
                + "    </install-in-user-type>\n"
                + "</permissions>";

        final String contents3 =
                  "<permissions>\n"
                + "    <install-in-user-type package=\"com.android.package2\">\n"
                + "        <install-in invalid-attribute=\"ADMIN\" />\n" // Ignore invalid attribute
                + "    </install-in-user-type>\n"
                + "    <install-in-user-type package=\"com.android.package2\">\n"
                + "        <install-in user-type=\"RESTRICTED\" />\n"  // Valid
                + "    </install-in-user-type>\n"
                + "    <install-in-user-type>\n" // Ignored since missing package name
                + "        <install-in user-type=\"ADMIN\" />\n"
                + "    </install-in-user-type>\n"
                + "</permissions>";

        Map<String, Set<String>> expectedWhite = new ArrayMap<>();
        expectedWhite.put("com.android.package1",
                new ArraySet<>(Arrays.asList("FULL", "PROFILE")));
        expectedWhite.put("com.android.package2",
                new ArraySet<>(Arrays.asList("FULL", "PROFILE", "RESTRICTED", "SYSTEM")));

        Map<String, Set<String>> expectedBlack = new ArrayMap<>();
        expectedBlack.put("com.android.package2",
                new ArraySet<>(Arrays.asList("GUEST", "PROFILE")));

        final File folder1 = createTempSubfolder("folder1");
        createTempFile(folder1, "permFile1.xml", contents1);

        final File folder2 = createTempSubfolder("folder2");
        createTempFile(folder2, "permFile2.xml", contents2);

        // Also, make a third file, but with the name folder1/permFile2.xml, to prove no conflicts.
        createTempFile(folder1, "permFile2.xml", contents3);

        mSysConfig.readPermissions(folder1, /* No permission needed anyway */ 0);
        mSysConfig.readPermissions(folder2, /* No permission needed anyway */ 0);

        Map<String, Set<String>> actualWhite = mSysConfig.getAndClearPackageToUserTypeWhitelist();
        Map<String, Set<String>> actualBlack = mSysConfig.getAndClearPackageToUserTypeBlacklist();

        assertEquals("Whitelist was not cleared", 0,
                mSysConfig.getAndClearPackageToUserTypeWhitelist().size());
        assertEquals("Blacklist was not cleared", 0,
                mSysConfig.getAndClearPackageToUserTypeBlacklist().size());

        assertEquals("Incorrect whitelist.", expectedWhite, actualWhite);
        assertEquals("Incorrect blacklist", expectedBlack, actualBlack);
    }

    /**
     * Creates folderName/fileName in the mTemporaryFolder and fills it with the contents.
     * @param folderName subdirectory of mTemporaryFolder to put the file, creating if needed
     * @return the folder
     */
    private File createTempSubfolder(String folderName)
            throws IOException {
        File folder = new File(mTemporaryFolder.getRoot(), folderName);
        folder.mkdir();
        return folder;
    }

    /**
     * Creates folderName/fileName in the mTemporaryFolder and fills it with the contents.
     * @param folder pre-existing subdirectory of mTemporaryFolder to put the file
     * @param fileName name of the file (e.g. filename.xml) to create
     * @param contents contents to write to the file
     * @return the folder containing the newly created file (not the file itself!)
     */
    private File createTempFile(File folder, String fileName, String contents)
            throws IOException {
        File file = new File(folder, fileName);
        BufferedWriter bw = new BufferedWriter(new FileWriter(file));
        bw.write(contents);
        bw.close();

        // Print to logcat for test debugging.
        Log.d(LOG_TAG, "Contents of file " + file.getAbsolutePath());
        Scanner input = new Scanner(file);
        while (input.hasNextLine()) {
            Log.d(LOG_TAG, input.nextLine());
        }

        return folder;
    }
}