SimpleEula.java

package org.sagemath.droid.utils;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
import android.content.DialogInterface;
import android.content.SharedPreferences;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.os.AsyncTask;
import android.preference.PreferenceManager;
import android.text.Html;
import android.text.method.LinkMovementMethod;
import android.util.Log;
import android.widget.TextView;
import org.apache.http.HttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONException;
import org.sagemath.droid.R;
import org.sagemath.droid.exceptions.SageInterruptedException;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URI;
import java.net.URISyntaxException;

/**
 * Original SimpleEula by <a href="https://github.com/donnfelker" >Donn Felker</a>
 * <p/>
 * Modified by Rasmi Elasmar for use in the Sage Android Application
 */
public class SimpleEula {

    private final static String TAG = "SimpleEula";
    private String EULA_PREFIX = "eula_";
    private boolean error;
    private Activity CellActivity;

    public SimpleEula(Activity context) {
        CellActivity = context;
    }

    private PackageInfo getPackageInfo() {
        PackageInfo pi = null;
        try {
            pi = CellActivity.getPackageManager().getPackageInfo(CellActivity.getPackageName(), PackageManager.GET_ACTIVITIES);
        } catch (PackageManager.NameNotFoundException e) {
            e.printStackTrace();
        }
        return pi;
    }

    public class EulaTask extends AsyncTask<Void, Void, String> {
        @Override
        protected String doInBackground(Void... voids) {
            String termsString = "";
            try {
                URI absolute = new URI("https://sagecell.sagemath.org");
                //URI(String scheme, String userInfo, String host, int port, String path, String query, String fragment)
                URI tosRelative = new URI("/tos.html");
                URI tosURI = absolute.resolve(tosRelative);
                /*
				int port = 10080;
				URI termsURI = new URI(tosURI.getScheme(), tosURI.getUserInfo(), tosURI.getHost(), port, 
						tosURI.getPath(), tosURI.getQuery(), tosURI.getFragment());
				Log.i(TAG, "Terms URI: " + termsURI.toString());
				*/
                HttpGet termsGet = new HttpGet();
                termsGet.setURI(tosURI);

                DefaultHttpClient termsHttpClient = new DefaultHttpClient();
                HttpResponse termsResponse = termsHttpClient.execute(termsGet);
                InputStream termsStream = termsResponse.getEntity().getContent();

                termsString = streamToString(termsStream);
            } catch (Exception e) {
                Log.e(TAG, "Error while getting EULA text." + e.getLocalizedMessage());
            }
            return termsString;
        }

        protected void onPostExecute(String html) {
            try {
                show(html);
            } catch (Exception e) {
                Log.e(TAG, "Error showing terms: " + e.getLocalizedMessage());
            }

        }
    }

    public void show(String termsHTML) throws IOException, SageInterruptedException, JSONException, URISyntaxException {
        PackageInfo versionInfo = getPackageInfo();

        // the eulaKey changes every time you increment the version number in the AndroidManifest.xml
        final String eulaKey = EULA_PREFIX + versionInfo.versionCode;
        final SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(CellActivity);
        boolean hasBeenShown = prefs.getBoolean(eulaKey, false);
        if (hasBeenShown == false) {

            // Show the Eula
            String title = CellActivity.getString(R.string.app_name) + " v" + versionInfo.versionName;

            //Includes the updates as well so users know what changed.
            //String message = CellActivity.getString(R.string.updates) + "\n\n" + CellActivity.getString(R.string.eula);


            Log.i(TAG, "Terms: " + termsHTML);
            String warning = "<p>By continuing, you indicate that you have read and agree to the <a href=\"http://sagecell.sagemath.org:10080/tos.html\">Sage Cell Server Terms of Usage</a>:</p>";

            if (termsHTML.contains("404") || termsHTML.contains("405")) {
                error = true;
            }

            if (!error) {
                AlertDialog dialog = new AlertDialog.Builder(CellActivity)
                        .setTitle(title)
                        .setMessage(Html.fromHtml((warning + termsHTML)))
                        .setPositiveButton(android.R.string.ok, new Dialog.OnClickListener() {

                            @Override
                            public void onClick(DialogInterface dialogInterface, int i) {
                                // Mark this version as read.
                                SharedPreferences.Editor editor = prefs.edit();
                                editor.putBoolean(eulaKey, true);
                                editor.commit();
                                dialogInterface.dismiss();
                            }
                        })
                        .setNegativeButton(android.R.string.cancel, new Dialog.OnClickListener() {
                            @Override
                            public void onClick(DialogInterface dialog, int which) {
                                // Close the activity as they have declined the EULA
                                CellActivity.finish();
                            }
                        }).create();
                dialog.show();
                // Make links clickable, via Michael Burton: http://about.me/michaelburton
                ((TextView) dialog.findViewById(android.R.id.message)).setMovementMethod(LinkMovementMethod.getInstance());
            }
        }
    }

    private String streamToString(InputStream is) {
        BufferedReader reader = new BufferedReader(new InputStreamReader(is));
        StringBuilder sb = new StringBuilder();

        String line = null;
        try {
            while ((line = reader.readLine()) != null) {
                sb.append(line + "\n");
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                is.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return sb.toString();
    }

}