/*
 * Copyright (C) 2015 Dominik Schürmann <dominik@dominikschuermann.de>
 *
 * This program 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 3 of the License, or
 * (at your option) any later version.
 *
 * This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package org.sufficientlysecure.keychain.ui;


import java.util.ArrayList;

import android.app.Activity;
import android.content.ContentResolver;
import android.content.Intent;
import android.database.Cursor;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

import org.sufficientlysecure.keychain.Constants;
import org.sufficientlysecure.keychain.R;
import org.sufficientlysecure.keychain.pgp.CanonicalizedSecretKey.SecretKeyType;
import org.sufficientlysecure.keychain.provider.KeychainContract.KeyRings;
import org.sufficientlysecure.keychain.util.ExportHelper;

public class BackupFragment extends Fragment {

    // This ids for multiple key export.
    private ArrayList<Long> mIdsForRepeatAskPassphrase;
    // This index for remembering the number of master key.
    private int mIndex;

    static final int REQUEST_REPEAT_PASSPHRASE = 1;


    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.backup_fragment, container, false);

        View backupAll = view.findViewById(R.id.backup_all);
        View backupPublicKeys = view.findViewById(R.id.backup_public_keys);

        backupAll.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                exportToFile(true);
            }
        });

        backupPublicKeys.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                exportToFile(false);
            }
        });

        return view;
    }

    private void exportToFile(boolean includeSecretKeys) {
        FragmentActivity activity = getActivity();
        if (activity == null) {
            return;
        }

        if (!includeSecretKeys) {
            ExportHelper exportHelper = new ExportHelper(activity);
            exportHelper.showExportKeysDialog(null, Constants.Path.APP_DIR_FILE, false);
            return;
        }

        new AsyncTask<ContentResolver,Void,ArrayList<Long>>() {
            @Override
            protected ArrayList<Long> doInBackground(ContentResolver... resolver) {
                ArrayList<Long> askPassphraseIds = new ArrayList<>();
                Cursor cursor = resolver[0].query(
                        KeyRings.buildUnifiedKeyRingsUri(), new String[] {
                                KeyRings.MASTER_KEY_ID,
                                KeyRings.HAS_SECRET,
                        }, KeyRings.HAS_SECRET + " != 0", null, null);
                try {
                    if (cursor != null) {
                        while (cursor.moveToNext()) {
                            SecretKeyType secretKeyType = SecretKeyType.fromNum(cursor.getInt(1));
                            switch (secretKeyType) {
                                // all of these make no sense to ask
                                case PASSPHRASE_EMPTY:
                                case GNU_DUMMY:
                                case DIVERT_TO_CARD:
                                case UNAVAILABLE:
                                    continue;
                                default: {
                                    long keyId = cursor.getLong(0);
                                    askPassphraseIds.add(keyId);
                                }
                            }
                        }
                    }
                } finally {
                    if (cursor != null) {
                        cursor.close();
                    }
                }
                return askPassphraseIds;
            }

            @Override
            protected void onPostExecute(ArrayList<Long> askPassphraseIds) {
                super.onPostExecute(askPassphraseIds);
                FragmentActivity activity = getActivity();
                if (activity == null) {
                    return;
                }

                mIdsForRepeatAskPassphrase = askPassphraseIds;
                mIndex = 0;

                if (mIdsForRepeatAskPassphrase.size() != 0) {
                    startPassphraseActivity();
                    return;
                }

                ExportHelper exportHelper = new ExportHelper(activity);
                exportHelper.showExportKeysDialog(null, Constants.Path.APP_DIR_FILE, true);
            }

        }.execute(activity.getContentResolver());

    }

    private void startPassphraseActivity() {
        Activity activity = getActivity();
        if (activity == null) {
            return;
        }

        Intent intent = new Intent(activity, PassphraseDialogActivity.class);
        long masterKeyId = mIdsForRepeatAskPassphrase.get(mIndex++);
        intent.putExtra(PassphraseDialogActivity.EXTRA_SUBKEY_ID, masterKeyId);
        startActivityForResult(intent, REQUEST_REPEAT_PASSPHRASE);
    }

    @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (requestCode == REQUEST_REPEAT_PASSPHRASE) {
            if (resultCode != Activity.RESULT_OK) {
                return;
            }
            if (mIndex < mIdsForRepeatAskPassphrase.size()) {
                startPassphraseActivity();
                return;
            }

            ExportHelper exportHelper = new ExportHelper(getActivity());
            exportHelper.showExportKeysDialog(null, Constants.Path.APP_DIR_FILE, true);
        }
    }
}