/*
 * Copyright (C) 2016 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 android.net.wifi;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertTrue;

import android.net.wifi.WifiEnterpriseConfig.Eap;
import android.net.wifi.WifiEnterpriseConfig.Phase2;
import android.os.Parcel;
import android.security.Credentials;
import android.test.suitebuilder.annotation.SmallTest;

import org.junit.Before;
import org.junit.Test;

import java.security.cert.X509Certificate;


/**
 * Unit tests for {@link android.net.wifi.WifiEnterpriseConfig}.
 */
@SmallTest
public class WifiEnterpriseConfigTest {
    // Maintain a ground truth of the keystore uri prefix which is expected by wpa_supplicant.
    public static final String KEYSTORE_URI = "keystore://";
    public static final String CA_CERT_PREFIX = KEYSTORE_URI + Credentials.CA_CERTIFICATE;
    public static final String KEYSTORES_URI = "keystores://";

    private WifiEnterpriseConfig mEnterpriseConfig;

    @Before
    public void setUp() throws Exception {
        mEnterpriseConfig = new WifiEnterpriseConfig();
    }

    @Test
    public void testSetGetSingleCaCertificate() {
        X509Certificate cert0 = FakeKeys.CA_CERT0;
        mEnterpriseConfig.setCaCertificate(cert0);
        assertEquals(mEnterpriseConfig.getCaCertificate(), cert0);
    }

    @Test
    public void testSetGetMultipleCaCertificates() {
        X509Certificate cert0 = FakeKeys.CA_CERT0;
        X509Certificate cert1 = FakeKeys.CA_CERT1;
        mEnterpriseConfig.setCaCertificates(new X509Certificate[] {cert0, cert1});
        X509Certificate[] result = mEnterpriseConfig.getCaCertificates();
        assertEquals(result.length, 2);
        assertTrue(result[0] == cert0 && result[1] == cert1);
    }

    @Test
    public void testSaveSingleCaCertificateAlias() {
        final String alias = "single_alias 0";
        mEnterpriseConfig.setCaCertificateAliases(new String[] {alias});
        assertEquals(getCaCertField(), CA_CERT_PREFIX + alias);
    }

    @Test
    public void testLoadSingleCaCertificateAlias() {
        final String alias = "single_alias 1";
        setCaCertField(CA_CERT_PREFIX + alias);
        String[] aliases = mEnterpriseConfig.getCaCertificateAliases();
        assertEquals(aliases.length, 1);
        assertEquals(aliases[0], alias);
    }

    @Test
    public void testSaveMultipleCaCertificates() {
        final String alias0 = "single_alias 0";
        final String alias1 = "single_alias 1";
        mEnterpriseConfig.setCaCertificateAliases(new String[] {alias0, alias1});
        assertEquals(getCaCertField(), String.format("%s%s %s",
                KEYSTORES_URI,
                WifiEnterpriseConfig.encodeCaCertificateAlias(Credentials.CA_CERTIFICATE + alias0),
                WifiEnterpriseConfig.encodeCaCertificateAlias(Credentials.CA_CERTIFICATE + alias1)));
    }

    @Test
    public void testLoadMultipleCaCertificates() {
        final String alias0 = "single_alias 0";
        final String alias1 = "single_alias 1";
        setCaCertField(String.format("%s%s %s",
                KEYSTORES_URI,
                WifiEnterpriseConfig.encodeCaCertificateAlias(Credentials.CA_CERTIFICATE + alias0),
                WifiEnterpriseConfig.encodeCaCertificateAlias(Credentials.CA_CERTIFICATE + alias1)));
        String[] aliases = mEnterpriseConfig.getCaCertificateAliases();
        assertEquals(aliases.length, 2);
        assertEquals(aliases[0], alias0);
        assertEquals(aliases[1], alias1);
    }

    private String getCaCertField() {
        return mEnterpriseConfig.getFieldValue(WifiEnterpriseConfig.CA_CERT_KEY, "");
    }

    private void setCaCertField(String value) {
        mEnterpriseConfig.setFieldValue(WifiEnterpriseConfig.CA_CERT_KEY, value);
    }

    // Retrieves the value for a specific key supplied to wpa_supplicant.
    private class SupplicantConfigExtractor implements WifiEnterpriseConfig.SupplicantSaver {
        private String mValue = null;
        private String mKey;

        SupplicantConfigExtractor(String key) {
            mKey = key;
        }

        @Override
        public boolean saveValue(String key, String value) {
            if (key.equals(mKey)) {
                mValue = value;
            }
            return true;
        }

        public String getValue() {
            return mValue;
        }
    }

    private String getSupplicantEapMethod() {
        SupplicantConfigExtractor entryExtractor = new SupplicantConfigExtractor(
                WifiEnterpriseConfig.EAP_KEY);
        mEnterpriseConfig.saveToSupplicant(entryExtractor);
        return entryExtractor.getValue();
    }

    private String getSupplicantPhase2Method() {
        SupplicantConfigExtractor entryExtractor = new SupplicantConfigExtractor(
                WifiEnterpriseConfig.PHASE2_KEY);
        mEnterpriseConfig.saveToSupplicant(entryExtractor);
        return entryExtractor.getValue();
    }

    /** Verifies the default value for EAP outer and inner methods */
    @Test
    public void eapInnerDefault() {
        assertEquals(null, getSupplicantEapMethod());
        assertEquals(null, getSupplicantPhase2Method());
    }

    /** Verifies that the EAP inner method is reset when we switch to TLS */
    @Test
    public void eapPhase2MethodForTls() {
        // Initially select an EAP method that supports an phase2.
        mEnterpriseConfig.setEapMethod(Eap.PEAP);
        mEnterpriseConfig.setPhase2Method(Phase2.MSCHAPV2);
        assertEquals("PEAP", getSupplicantEapMethod());
        assertEquals("\"auth=MSCHAPV2\"", getSupplicantPhase2Method());

        // Change the EAP method to another type which supports a phase2.
        mEnterpriseConfig.setEapMethod(Eap.TTLS);
        assertEquals("TTLS", getSupplicantEapMethod());
        assertEquals("\"auth=MSCHAPV2\"", getSupplicantPhase2Method());

        // Change the EAP method to TLS which does not support a phase2.
        mEnterpriseConfig.setEapMethod(Eap.TLS);
        assertEquals(null, getSupplicantPhase2Method());
    }

    /** Verfies that the EAP inner method is reset when we switch phase2 to NONE */
    @Test
    public void eapPhase2None() {
        // Initially select an EAP method that supports an phase2.
        mEnterpriseConfig.setEapMethod(Eap.PEAP);
        mEnterpriseConfig.setPhase2Method(Phase2.MSCHAPV2);
        assertEquals("PEAP", getSupplicantEapMethod());
        assertEquals("\"auth=MSCHAPV2\"", getSupplicantPhase2Method());

        // Change the phase2 method to NONE and ensure the value is cleared.
        mEnterpriseConfig.setPhase2Method(Phase2.NONE);
        assertEquals(null, getSupplicantPhase2Method());
    }

    /** Verfies that the correct "autheap" parameter is supplied for TTLS/GTC. */
    @Test
    public void peapGtcToTtls() {
        mEnterpriseConfig.setEapMethod(Eap.PEAP);
        mEnterpriseConfig.setPhase2Method(Phase2.GTC);
        assertEquals("PEAP", getSupplicantEapMethod());
        assertEquals("\"auth=GTC\"", getSupplicantPhase2Method());

        mEnterpriseConfig.setEapMethod(Eap.TTLS);
        assertEquals("TTLS", getSupplicantEapMethod());
        assertEquals("\"autheap=GTC\"", getSupplicantPhase2Method());
    }

    /** Verfies that the correct "auth" parameter is supplied for PEAP/GTC. */
    @Test
    public void ttlsGtcToPeap() {
        mEnterpriseConfig.setEapMethod(Eap.TTLS);
        mEnterpriseConfig.setPhase2Method(Phase2.GTC);
        assertEquals("TTLS", getSupplicantEapMethod());
        assertEquals("\"autheap=GTC\"", getSupplicantPhase2Method());

        mEnterpriseConfig.setEapMethod(Eap.PEAP);
        assertEquals("PEAP", getSupplicantEapMethod());
        assertEquals("\"auth=GTC\"", getSupplicantPhase2Method());
    }

    /** Verfies that the copy constructor preseves the inner method information. */
    @Test
    public void copyConstructor() {
        WifiEnterpriseConfig enterpriseConfig = new WifiEnterpriseConfig();
        enterpriseConfig.setEapMethod(Eap.TTLS);
        enterpriseConfig.setPhase2Method(Phase2.GTC);
        mEnterpriseConfig = new WifiEnterpriseConfig(enterpriseConfig);
        assertEquals("TTLS", getSupplicantEapMethod());
        assertEquals("\"autheap=GTC\"", getSupplicantPhase2Method());
    }

    /** Verfies that parceling a WifiEnterpriseConfig preseves method information. */
    @Test
    public void parcelConstructor() {
        WifiEnterpriseConfig enterpriseConfig = new WifiEnterpriseConfig();
        enterpriseConfig.setEapMethod(Eap.TTLS);
        enterpriseConfig.setPhase2Method(Phase2.GTC);
        Parcel parcel = Parcel.obtain();
        enterpriseConfig.writeToParcel(parcel, 0);
        parcel.setDataPosition(0);  // Allow parcel to be read from the beginning.
        mEnterpriseConfig = WifiEnterpriseConfig.CREATOR.createFromParcel(parcel);
        assertEquals("TTLS", getSupplicantEapMethod());
        assertEquals("\"autheap=GTC\"", getSupplicantPhase2Method());
    }

    /** Verifies proper operation of the getKeyId() method. */
    @Test
    public void getKeyId() {
        assertEquals("NULL", mEnterpriseConfig.getKeyId(null));
        WifiEnterpriseConfig enterpriseConfig = new WifiEnterpriseConfig();
        enterpriseConfig.setEapMethod(Eap.TTLS);
        enterpriseConfig.setPhase2Method(Phase2.GTC);
        assertEquals("TTLS_GTC", mEnterpriseConfig.getKeyId(enterpriseConfig));
        mEnterpriseConfig.setEapMethod(Eap.PEAP);
        mEnterpriseConfig.setPhase2Method(Phase2.MSCHAPV2);
        assertEquals("PEAP_MSCHAPV2", mEnterpriseConfig.getKeyId(enterpriseConfig));
    }

    /** Verifies that passwords are not displayed in toString. */
    @Test
    public void passwordNotInToString() {
        String password = "supersecret";
        mEnterpriseConfig.setPassword(password);
        assertFalse(mEnterpriseConfig.toString().contains(password));
    }
}