/*
 * Copyright 2017 Jeremy Jamet / Kunzisoft.
 *
 * This file is part of KeePass DX.
 *
 *  KeePass DX is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  KeePass DX is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with KeePass DX.  If not, see <http://www.gnu.org/licenses/>.
 *
 */
package com.keepassdroid.autofill;

import android.app.assist.AssistStructure;
import android.content.IntentSender;
import android.os.Build;
import android.os.Bundle;
import android.os.CancellationSignal;
import android.service.autofill.AutofillService;
import android.service.autofill.FillCallback;
import android.service.autofill.FillRequest;
import android.service.autofill.FillResponse;
import android.service.autofill.SaveCallback;
import android.service.autofill.SaveRequest;
import android.support.annotation.NonNull;
import android.support.annotation.RequiresApi;
import android.util.Log;
import android.view.autofill.AutofillId;
import android.widget.RemoteViews;

import com.keepassdroid.AutoFillAuthActivity;
import com.kunzisoft.keepass.R;

import java.util.Arrays;

@RequiresApi(api = Build.VERSION_CODES.O)
public class KeeAutofillService extends AutofillService {
    private static final String TAG = "KeeAutofillService";

    @Override
    public void onFillRequest(@NonNull FillRequest request, @NonNull CancellationSignal cancellationSignal,
                              @NonNull FillCallback callback) {
        AssistStructure structure = request.getFillContexts()
                .get(request.getFillContexts().size() - 1).getStructure();

        final Bundle clientState = request.getClientState();

        cancellationSignal.setOnCancelListener(() ->
                Log.e(TAG, "Cancel autofill not implemented in this sample.")
        );

        // Parse AutoFill data in Activity
        StructureParser parser = new StructureParser(getApplicationContext(), structure);
        // TODO: try / catch on other places (onSave, auth activity, etc...)
        try {
            parser.parseForFill();
        } catch (SecurityException e) {
            // TODO: handle cases where DAL didn't pass by showing a custom UI asking the user
            // to confirm the mapping. Might require subclassing SecurityException.
            Log.e(TAG, "Security exception handling " + request);
            callback.onFailure(e.getMessage());
            return;
        }
        AutofillFieldMetadataCollection autofillFields = parser.getAutofillFields();
        FillResponse.Builder responseBuilder = new FillResponse.Builder();
        // Check user's settings for authenticating Responses and Datasets.
        AutofillId[] autofillIds = autofillFields.getAutofillIds();
        if (!Arrays.asList(autofillIds).isEmpty()) {
            // If the entire Autofill Response is authenticated, AuthActivity is used
            // to generate Response.
            IntentSender sender = AutoFillAuthActivity.getAuthIntentSenderForResponse(this);

            RemoteViews presentation =
                    new RemoteViews(getPackageName(), R.layout.autofill_service_unlock);
            presentation.setTextViewText(R.id.text, getString(R.string.autofill_sign_in_prompt));

            responseBuilder
                    .setAuthentication(autofillIds, sender, presentation);
            callback.onSuccess(responseBuilder.build());
        }
    }

    @Override
    public void onSaveRequest(@NonNull SaveRequest request, @NonNull SaveCallback callback) {
        // Do nothing if is fill
    }
}