package course.labs.notificationslab;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.net.URL;

import android.app.Activity;
import android.app.Notification;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.os.AsyncTask;
import android.util.Log;
import android.widget.RemoteViews;

public class DownloaderTask extends AsyncTask<String, Void, String[]> {

    private static final int SIM_NETWORK_DELAY = 5000;
    private static final String TAG = "Lab-Notifications";
    private final int MY_NOTIFICATION_ID = 11151990;
    private String mFeeds[] = new String[3];
    private MainActivity mParentActivity;
    private Context mApplicationContext;

    // Change this variable to false if you do not have a stable network
    // connection
    private static final boolean HAS_NETWORK_CONNECTION = true;

    // Raw feed file IDs used if you do not have a stable connection
    public static final int txtFeeds[] = { R.raw.tswift, R.raw.rblack, R.raw.lgaga };

    // Constructor
    public DownloaderTask(MainActivity parentActivity) {
        super();
        mParentActivity = parentActivity;
        mApplicationContext = parentActivity.getApplicationContext();
    }

    @Override
    protected String[] doInBackground(String... urlParameters) {
        log("Entered doInBackground()");
        return download(urlParameters);
    }

    private String[] download(String urlParameters[]) {

        boolean downloadCompleted = false;

        try {

            for (int idx = 0; idx < urlParameters.length; idx++) {

                URL url = new URL(urlParameters[idx]);
                try {
                    Thread.sleep(SIM_NETWORK_DELAY);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }

                InputStream inputStream;
                BufferedReader in;

                // Alternative for students without
                // a network connection
                if (HAS_NETWORK_CONNECTION) {
                    inputStream = url.openStream();
                    in = new BufferedReader(new InputStreamReader(inputStream));
                } else {
                    inputStream = mApplicationContext.getResources().openRawResource(txtFeeds[idx]);
                    in = new BufferedReader(new InputStreamReader(inputStream));
                }

                String readLine;
                StringBuffer buf = new StringBuffer();

                while ((readLine = in.readLine()) != null) {
                    buf.append(readLine);
                }

                mFeeds[idx] = buf.toString();

                if (null != in) {
                    in.close();
                }
            }

            downloadCompleted = true;

        } catch (IOException e) {
            e.printStackTrace();
        }

        log("Tweet Download Completed:" + downloadCompleted);

        notify(downloadCompleted);

        return mFeeds;
    }

    // Call back to the MainActivity to update the feed display
    @Override
    protected void onPostExecute(String[] result) {
        super.onPostExecute(result);

        if (mParentActivity != null) {
            mParentActivity.setRefreshed(result);
        }

    }

    // If necessary, notifies the user that the tweet downloads are complete.
    // Sends an ordered broadcast back to the BroadcastReceiver in MainActivity
    // to determine whether the notification is necessary.
    private void notify(final boolean success) {
        log("Entered notify()");
        final Intent restartMainActivtyIntent = new Intent(mApplicationContext, MainActivity.class);
        restartMainActivtyIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);

        if (success) {
            // Save tweets to a file
            saveTweetsToFile();
        }

        // Sends an ordered broadcast to determine whether MainActivity is
        // active and in the foreground. Creates a new BroadcastReceiver
        // to receive a result indicating the state of MainActivity

        // The Action for this broadcast Intent is MainActivity.DATA_REFRESHED_ACTION
        // The result Activity.RESULT_OK, indicates that MainActivity is active and
        // in the foreground.
        mApplicationContext.sendOrderedBroadcast(
                new Intent(MainActivity.DATA_REFRESHED_ACTION), null, new BroadcastReceiver() {

                    final String failMsg = "Download has failed. Please retry Later.";
                    final String successMsg = "Download completed successfully.";

                    @Override
                    public void onReceive(Context context, Intent intent) {

                        log("Entered result receiver's onReceive() method");

                        // TODO: Check whether the result code is RESULT_OK

                        if (/*change this*/ true) {

                            // TODO:  If so, create a PendingIntent using the
                            // restartMainActivityIntent and set its flags
                            // to FLAG_UPDATE_CURRENT

                            final PendingIntent pendingIntent = null;

                            // Uses R.layout.custom_notification for the
                            // layout of the notification View. The xml
                            // file is in res/layout/custom_notification.xml
                            RemoteViews mContentView = new RemoteViews(
                                    mApplicationContext.getPackageName(),
                                    R.layout.custom_notification);

                            // TODO: Set the notification View's text to
                            // reflect whether or the download completed
                            // successfully

                            // TODO: Use the Notification.Builder class to
                            // create the Notification. You will have to set
                            // several pieces of information. You can use
                            // android.R.drawable.stat_sys_warning
                            // for the small icon. You should also setAutoCancel(true).

                            Notification.Builder notificationBuilder = null;

                            // TODO: Send the notification

                            log("Notification Area Notification sent");
                        }
                    }
                }, null, 0, null, null);
    }

    // Saves the tweets to a file
    private void saveTweetsToFile() {
        PrintWriter writer = null;
        try {
            FileOutputStream fos = mApplicationContext.openFileOutput(
                    MainActivity.TWEET_FILENAME, Context.MODE_PRIVATE);
            writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(
                            fos)));

            for (String s : mFeeds) {
                writer.println(s);
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (null != writer) {
                writer.close();
            }
        }
    }

    // Simplified log output method
    private void log(String msg) {
        try {
            Thread.sleep(500);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        Log.i(TAG, msg);
    }
}