zTrader Cryptography

package co.bandicoot.ztrader;

import java.util.HashMap;

import android.app.ActionBar;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.content.pm.PackageManager.NameNotFoundException;
import android.net.Uri;
import android.os.Bundle;
import android.text.Editable;
import android.text.TextWatcher;
import android.view.KeyEvent;
import android.view.View;
import android.view.inputmethod.EditorInfo;
import android.view.inputmethod.InputMethodManager;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageButton;
import android.widget.RelativeLayout;
import android.widget.TextView;
import android.widget.TextView.OnEditorActionListener;
import android.widget.Toast;

public class CreateKeyActivity extends Activity {

    private static final int REQUEST_API_QR_CODE = 0;
    private static final int REQUEST_SECRET_QR_CODE = 1;

    Button cancelButton, encryptButton;
    ImageButton scanApiButton, scanSecretButton;
    EditText apiEditText, secretEditText, userIdEditText, passwordEditText;
    RelativeLayout secretLayout;
    int exchange;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_create_key);
        exchange = getIntent().getIntExtra("exchange", 0);

        ActionBar actionBar = getActionBar();
        actionBar.setIcon(R.drawable.ic_action_accounts_light);
        actionBar.setDisplayHomeAsUpEnabled(true);
        actionBar.setTitle(ExchangeService.getName(exchange));

        scanApiButton = (ImageButton) findViewById(R.id.scanApiButton);
        scanSecretButton = (ImageButton) findViewById(R.id.scanSecretButton);
        cancelButton = (Button) findViewById(R.id.cancelButton);
        encryptButton = (Button) findViewById(R.id.encryptButton);
        apiEditText = (EditText) findViewById(R.id.apiEditText);
        secretEditText = (EditText) findViewById(R.id.secretEditText);
        passwordEditText = (EditText) findViewById(R.id.passwordEditText);
        userIdEditText = (EditText) findViewById(R.id.userIdEditText);
        secretLayout = (RelativeLayout) findViewById(R.id.secretLayout);

        if (exchange == ExchangeService.BITSTAMP) {
            userIdEditText.setVisibility(View.VISIBLE);
        } else if (exchange == ExchangeService.JUSTCOIN) {
            secretLayout.setVisibility(View.GONE);
        }

        if (exchange == ExchangeService.CRYPTSY) {
            apiEditText.setHint(getText(R.string.public_key));
            secretEditText.setHint(getText(R.string.private_key));
        } else {
            apiEditText.setHint(getText(R.string.api_key));
            secretEditText.setHint(getText(R.string.secret));
        }

        passwordEditText.addTextChangedListener(new TextWatcher() {

            @Override
            public void afterTextChanged(Editable arg0) {
                if (passwordEditText.getText().toString().length() > 7) {
                    encryptButton.setEnabled(true);
                    passwordEditText.setImeActionLabel(getText(R.string.encrypt), EditorInfo.IME_ACTION_DONE);
                } else {
                    encryptButton.setEnabled(false);
                    passwordEditText.setImeActionLabel(getText(R.string.done), EditorInfo.IME_ACTION_DONE);
                }
            }

            @Override
            public void beforeTextChanged(CharSequence arg0, int arg1, int arg2, int arg3) {

            }

            @Override
            public void onTextChanged(CharSequence arg0, int arg1, int arg2, int arg3) {

            }

        });

        passwordEditText.setOnEditorActionListener(new OnEditorActionListener() {

            @Override
            public boolean onEditorAction(TextView arg0, int arg1, KeyEvent arg2) {
                if (arg1 == EditorInfo.IME_ACTION_DONE && apiEditText.getText().length() > 0
                        && secretEditText.getText().length() > 0) {
                    encrypt(null);
                } else {
                    ((InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE))
                            .hideSoftInputFromWindow(CreateKeyActivity.this.getCurrentFocus()
                                    .getWindowToken(), InputMethodManager.HIDE_NOT_ALWAYS);
                }
                return true;
            }
        });

        scanApiButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (isPackageInstalled("com.google.zxing.client.android")) {
                    if (isCameraAvailable()) {
                        Intent intent = new Intent("com.google.zxing.client.android.SCAN");
                        intent.putExtra("SCAN_MODE", "QR_CODE_MODE");
                        intent.putExtra("SAVE_HISTORY", false);
                        startActivityForResult(intent, REQUEST_API_QR_CODE);
                    } else {
                        Toast.makeText(CreateKeyActivity.this, getText(R.string.camera_unavailable),
                                Toast.LENGTH_SHORT).show();
                    }
                } else {
                    showSendToMarketDialog();
                }
            }
        });

        scanSecretButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (isPackageInstalled("com.google.zxing.client.android")) {
                    if (isCameraAvailable()) {
                        Intent intent = new Intent("com.google.zxing.client.android.SCAN");
                        intent.putExtra("SCAN_MODE", "QR_CODE_MODE");
                        intent.putExtra("SAVE_HISTORY", false);
                        startActivityForResult(intent, REQUEST_SECRET_QR_CODE);
                    } else {
                        Toast.makeText(CreateKeyActivity.this, getText(R.string.camera_unavailable),
                                Toast.LENGTH_SHORT).show();
                    }
                } else {
                    showSendToMarketDialog();
                }
            }
        });

        cancelButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                setResult(RESULT_CANCELED, null);
                finish();
            }
        });
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {

        super.onActivityResult(requestCode, resultCode, data);
        if (requestCode == REQUEST_API_QR_CODE) {
            if (resultCode == RESULT_OK) {
                String contents = data.getStringExtra("SCAN_RESULT");
                if (contents != null) {
                    apiEditText.setText(contents);
                }
            }
        } else if (requestCode == REQUEST_SECRET_QR_CODE) {
            if (resultCode == RESULT_OK) {
                String contents = data.getStringExtra("SCAN_RESULT");
                if (contents != null) {
                    secretEditText.setText(contents);
                }
            }
        }

    }

    public void encrypt(View v) {

        try {

            Intent returnIntent = new Intent();
            returnIntent.putExtra("exchange", exchange);

            HashMap<Integer, ExchangeData> exchangeContainer = Utils
                    .getExchangeContainer(getApplicationContext());
            String encryptedApi = EncodeDecodeAES.encrypt(passwordEditText.getText().toString(), apiEditText
                    .getText().toString());
            exchangeContainer.get(exchange).setEncryptedApi(encryptedApi);

            if (secretLayout.getVisibility() == View.VISIBLE) {
                String encryptedSecret = EncodeDecodeAES.encrypt(passwordEditText.getText().toString(),
                        secretEditText.getText().toString());
                exchangeContainer.get(exchange).setEncryptedSecret(encryptedSecret);
            }

            if (userIdEditText.getVisibility() == View.VISIBLE) {
                String encryptedUserId = EncodeDecodeAES.encrypt(passwordEditText.getText().toString(),
                        userIdEditText.getText().toString());
                exchangeContainer.get(exchange).setEncryptedUserId(encryptedUserId);
            }

            Utils.saveExchangeContainer(getApplicationContext(), exchangeContainer);

            setResult(RESULT_OK, returnIntent);
            finish();
        } catch (Exception e) {
            Toast.makeText(
                    CreateKeyActivity.this,
                    getText(R.string.encryption_failed) + " " + e.getClass().getName() + ": "
                            + e.getMessage(), Toast.LENGTH_LONG).show();
            e.printStackTrace();
        }

    }

    private boolean isCameraAvailable() {

        PackageManager pm = getPackageManager();
        return pm.hasSystemFeature(PackageManager.FEATURE_CAMERA);

    }

    private boolean isPackageInstalled(String packagename) {

        PackageManager pm = getPackageManager();
        try {
            pm.getPackageInfo(packagename, PackageManager.GET_ACTIVITIES);
            return true;
        } catch (NameNotFoundException e) {
            return false;
        }

    }

    private void showSendToMarketDialog() {

        new AlertDialog.Builder(this).setTitle(getText(R.string.scanner_required))
                .setMessage(getText(R.string.zxing_msg))
                .setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface arg0, int arg1) {
                        Uri marketUri = Uri.parse("market://details?id=com.google.zxing.client.android");
                        Intent marketIntent = new Intent(Intent.ACTION_VIEW, marketUri);
                        startActivity(marketIntent);
                    }
                }).setNegativeButton(android.R.string.no, null).create().show();

    }

}