/*
 * Copyright (C) 2018 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.biometrics;

import android.annotation.NonNull;
import android.app.admin.DevicePolicyManager;
import android.app.settings.SettingsEnums;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.hardware.biometrics.BiometricManager;
import android.hardware.biometrics.BiometricManager.Authenticators;
import android.os.Bundle;
import android.os.UserHandle;
import android.provider.Settings;
import android.util.Log;

import com.android.settings.SetupWizardUtils;
import com.android.settings.biometrics.face.FaceEnrollIntroduction;
import com.android.settings.biometrics.fingerprint.FingerprintEnrollFindSensor;
import com.android.settings.biometrics.fingerprint.FingerprintEnrollIntroduction;
import com.android.settings.biometrics.fingerprint.SetupFingerprintEnrollIntroduction;
import com.android.settings.core.InstrumentedActivity;
import com.android.settings.password.ChooseLockGeneric;
import com.android.settings.password.ChooseLockSettingsHelper;

import com.google.android.setupcompat.util.WizardManagerHelper;

/**
 * Trampoline activity launched by the {@code android.settings.BIOMETRIC_ENROLL} action which
 * shows the user an appropriate enrollment flow depending on the device's biometric hardware.
 * This activity must only allow enrollment of biometrics that can be used by
 * {@link android.hardware.biometrics.BiometricPrompt}.
 */
public class BiometricEnrollActivity extends InstrumentedActivity {

    private static final String TAG = "BiometricEnrollActivity";

    // Intent extra. If true, biometric enrollment should skip introductory screens. Currently
    // this only applies to fingerprint.
    public static final String EXTRA_SKIP_INTRO = "skip_intro";

    public static final class InternalActivity extends BiometricEnrollActivity {}

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        // Default behavior is to enroll BIOMETRIC_WEAK or above. See ACTION_BIOMETRIC_ENROLL.
        final int authenticators = getIntent().getIntExtra(
                Settings.EXTRA_BIOMETRIC_AUTHENTICATORS_ALLOWED, Authenticators.BIOMETRIC_WEAK);

        Log.d(TAG, "Authenticators: " + authenticators);

        final PackageManager pm = getApplicationContext().getPackageManager();
        final boolean hasFeatureFingerprint =
                pm.hasSystemFeature(PackageManager.FEATURE_FINGERPRINT);
        final boolean hasFeatureFace = pm.hasSystemFeature(PackageManager.FEATURE_FACE);
        final boolean isSetupWizard = WizardManagerHelper.isAnySetupWizard(getIntent());

        if (isSetupWizard) {
            if (hasFeatureFace && hasFeatureFingerprint) {
                // TODO(b/162341940, b/152242790) this should show a multi-biometric selection
                //  screen
                launchFingerprintOnlyEnroll();
            } else if (hasFeatureFace) {
                launchFaceOnlyEnroll();
            } else if (hasFeatureFingerprint) {
                launchFingerprintOnlyEnroll();
            } else {
                Log.e(TAG, "No biometrics but started by SUW?");
                finish();
            }
        } else {
            // If the caller is not setup wizard, and the user has something enrolled, finish.
            final BiometricManager bm = getSystemService(BiometricManager.class);
            final @BiometricManager.BiometricError int result = bm.canAuthenticate(authenticators);
            if (result != BiometricManager.BIOMETRIC_ERROR_NONE_ENROLLED) {
                Log.e(TAG, "Unexpected result: " + result);
                finish();
                return;
            }

            // This will need to be updated if the device has sensors other than BIOMETRIC_STRONG
            if (authenticators == BiometricManager.Authenticators.DEVICE_CREDENTIAL) {
                launchCredentialOnlyEnroll();
            } else if (hasFeatureFace && hasFeatureFingerprint) {
                // TODO(b/162341940, b/152242790) this should show a multi-biometric selection
                //  screen
                launchFingerprintOnlyEnroll();
            } else if (hasFeatureFingerprint) {
                launchFingerprintOnlyEnroll();
            } else if (hasFeatureFace) {
                launchFaceOnlyEnroll();
            } else {
                Log.e(TAG, "Unknown state, finishing");
                finish();
            }
        }
    }

    /**
     * @param intent Enrollment activity that should be started (e.g. FaceEnrollIntroduction.class,
     *               etc).
     */
    private void launchEnrollActivity(@NonNull Intent intent) {
        intent.setFlags(Intent.FLAG_ACTIVITY_FORWARD_RESULT);
        if (this instanceof InternalActivity) {
            // Propagate challenge and user Id from ChooseLockGeneric.
            final byte[] token = getIntent()
                    .getByteArrayExtra(ChooseLockSettingsHelper.EXTRA_KEY_CHALLENGE_TOKEN);
            final int userId = getIntent()
                    .getIntExtra(Intent.EXTRA_USER_ID, UserHandle.USER_NULL);
            final long gkPwHandle = getIntent().getLongExtra(
                    ChooseLockSettingsHelper.EXTRA_KEY_GK_PW_HANDLE, 0L);

            intent.putExtra(ChooseLockSettingsHelper.EXTRA_KEY_CHALLENGE_TOKEN, token);
            intent.putExtra(Intent.EXTRA_USER_ID, userId);
            if (gkPwHandle != 0L) {
                intent.putExtra(ChooseLockSettingsHelper.EXTRA_KEY_GK_PW_HANDLE, gkPwHandle);
            }
        }

        startActivity(intent);
        finish();
    }

    private void launchCredentialOnlyEnroll() {
        final Intent intent;
        // If only device credential was specified, ask the user to only set that up.
        intent = new Intent(this, ChooseLockGeneric.class);
        intent.putExtra(ChooseLockGeneric.ChooseLockGenericFragment.MINIMUM_QUALITY_KEY,
                DevicePolicyManager.PASSWORD_QUALITY_SOMETHING);
        launchEnrollActivity(intent);
    }

    private void launchFingerprintOnlyEnroll() {
        final Intent intent;
        // ChooseLockGeneric can request to start fingerprint enroll bypassing the intro screen.
        if (getIntent().getBooleanExtra(EXTRA_SKIP_INTRO, false)
                && this instanceof InternalActivity) {
            intent = getFingerprintFindSensorIntent();
        } else {
            intent = getFingerprintIntroIntent();
        }
        launchEnrollActivity(intent);
    }

    private void launchFaceOnlyEnroll() {
        final Intent intent = getFaceIntroIntent();
        launchEnrollActivity(intent);
    }

    private Intent getFingerprintFindSensorIntent() {
        Intent intent = new Intent(this, FingerprintEnrollFindSensor.class);
        SetupWizardUtils.copySetupExtras(getIntent(), intent);
        return intent;
    }

    private Intent getFingerprintIntroIntent() {
        if (WizardManagerHelper.isAnySetupWizard(getIntent())) {
            Intent intent = new Intent(this, SetupFingerprintEnrollIntroduction.class);
            WizardManagerHelper.copyWizardManagerExtras(getIntent(), intent);
            return intent;
        } else {
            return new Intent(this, FingerprintEnrollIntroduction.class);
        }
    }

    private Intent getFaceIntroIntent() {
        Intent intent = new Intent(this, FaceEnrollIntroduction.class);
        WizardManagerHelper.copyWizardManagerExtras(getIntent(), intent);
        return intent;
    }

    @Override
    public int getMetricsCategory() {
        return SettingsEnums.BIOMETRIC_ENROLL_ACTIVITY;
    }
}