/*
 * Copyright (c) 2017 dm77, m2049r
 *
 * 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.m2049r.xmrwallet;

import android.content.Context;
import android.os.Bundle;
import android.os.Handler;
import android.support.v4.app.Fragment;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Toast;

import com.google.zxing.BarcodeFormat;
import com.google.zxing.Result;

import me.dm7.barcodescanner.zxing.ZXingScannerView;

public class ScannerFragment extends Fragment implements ZXingScannerView.ResultHandler {
    static final String TAG = "ScannerFragment";

    Listener activityCallback;

    public interface Listener {
        boolean onAddressScanned(String uri);
    }

    private ZXingScannerView mScannerView;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        Log.d(TAG, "onCreateView");
        mScannerView = new ZXingScannerView(getActivity());
        return mScannerView;
    }

    @Override
    public void onResume() {
        super.onResume();
        Log.d(TAG, "onResume");
        mScannerView.setResultHandler(this);
        mScannerView.startCamera();
    }

    static final String QR_SCHEME = "monero:";
    static final String QR_PAYMENTID = "tx_payment_id";
    static final String QR_AMOUNT = "tx_amount";

    @Override
    public void handleResult(Result rawResult) {
        if ((rawResult.getBarcodeFormat() == BarcodeFormat.QR_CODE) &&
                (rawResult.getText().startsWith(QR_SCHEME))) {
            if (activityCallback.onAddressScanned(rawResult.getText())) {
                return;
            } else {
                Toast.makeText(getActivity(), getString(R.string.send_qr_address_invalid), Toast.LENGTH_SHORT).show();
            }
        } else {
            Toast.makeText(getActivity(), getString(R.string.send_qr_invalid), Toast.LENGTH_SHORT).show();
        }

        // Note from dm77:
        // * Wait 2 seconds to resume the preview.
        // * On older devices continuously stopping and resuming camera preview can result in freezing the app.
        // * I don't know why this is the case but I don't have the time to figure out.
        Handler handler = new Handler();
        handler.postDelayed(new

                                    Runnable() {
                                        @Override
                                        public void run() {
                                            mScannerView.resumeCameraPreview(ScannerFragment.this);
                                        }
                                    }, 2000);
    }

    @Override
    public void onPause() {
        Log.d(TAG, "onPause");
        mScannerView.stopCamera();
        super.onPause();
    }

    @Override
    public void onAttach(Context context) {
        super.onAttach(context);
        if (context instanceof Listener) {
            this.activityCallback = (Listener) context;
        } else {
            throw new ClassCastException(context.toString()
                    + " must implement Listener");
        }
    }
}