package com.example.top10downloadedapps;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;

import android.os.AsyncTask;
import android.os.Bundle;

import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.ArrayAdapter;
import android.widget.ListView;

import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;

public class MainActivity extends AppCompatActivity {
    private static final String TAG = "MainActivity";
    private ListView listView;
    private int feedLimit = 10;
    private String feedCachedUrl = "INVALIDATED";
    private String feedUrl = "http://ax.itunes.apple.com/WebObjects/MZStoreServices.woa/ws/RSS/topfreeapplications/limit=%d/xml";
    private static final String STATE_URL = "feedUrl";
    private static final String STATE_LIMIT = "feedLimit";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        listView = (ListView) findViewById(R.id.listView);
        if(savedInstanceState!=null)
        {
            feedUrl=savedInstanceState.getString(STATE_URL);
            feedLimit=savedInstanceState.getInt(STATE_LIMIT);

        }
        downloadUrl(String.format(feedUrl, feedLimit));

    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.feeds_menu, menu);

        return true;
    }

    @Override
    public boolean onOptionsItemSelected(@NonNull MenuItem item) {
        int id = item.getItemId();

        switch (id) {
            case R.id.mnuFree:
                feedUrl = "http://ax.itunes.apple.com/WebObjects/MZStoreServices.woa/ws/RSS/topfreeapplications/limit=%d/xml";
                break;
            case R.id.mnuPaid:
                feedUrl = "http://ax.itunes.apple.com/WebObjects/MZStoreServices.woa/ws/RSS/toppaidapplications/limit=%d/xml";
                break;
            case R.id.mnuSongs:
                feedUrl = "http://ax.itunes.apple.com/WebObjects/MZStoreServices.woa/ws/RSS/topsongs/limit=%d/xml";
                break;
            case R.id.mnuTop10:
            case R.id.mnuTop25:
                if (!item.isChecked()) {
                    item.setChecked(true);
                    feedLimit = 35 - feedLimit;
                    Log.d(TAG, "onOptionsItemSelected: " + item.getTitle() + "setting feedLimit to " + feedLimit);
                } else {
                    Log.d(TAG, "onOptionsItemSelected: " + item.getTitle() + "feedLimit unchanged");
                }
                break;
            case R.id.mnuRefresh:
                feedCachedUrl="INVALIDATED";
            default:
                return super.onOptionsItemSelected(item);
        }
        downloadUrl(String.format(feedUrl, feedLimit));
        return true;
    }

    @Override
    protected void onSaveInstanceState(@NonNull Bundle outState) {
        outState.putString(STATE_URL,feedUrl);
        outState.putInt(STATE_LIMIT,feedLimit);
        super.onSaveInstanceState(outState);
    }

    public void downloadUrl(String feedUrl) {
        if(!feedUrl.equals(feedCachedUrl)){
            Log.d(TAG, "onCreate: starting Asynctask");
            DownloadData downloadData = new DownloadData();
            downloadData.execute(feedUrl);
          
            feedCachedUrl=feedUrl;
            Log.d(TAG, "onCreate: done");
        }
        else{
            Log.d(TAG, "downloadUrl: url not changed");
        }

    }

    private class DownloadData extends AsyncTask<String, Void, String> {
        private static final String TAG = "DownloadData";

        @Override
        protected void onPostExecute(String s) {
            super.onPostExecute(s);
//            Log.d(TAG, "onPostExecute: parameter is " + s);
            ParseApplications parseApplications = new ParseApplications();
            parseApplications.parse(s);
//            ArrayAdapter<FeedEntry> arrayAdapter = new ArrayAdapter<FeedEntry>(MainActivity.this, R.layout.list_item, parseApplications.getApplications());
//            listView.setAdapter(arrayAdapter);
            FeedAdapter feedAdapter = new FeedAdapter(MainActivity.this, R.layout.list_record, parseApplications.getApplications());
            listView.setAdapter(feedAdapter);
        }

        @Override
        protected String doInBackground(String... strings) {
            Log.d(TAG, "doInBackground: starts with " + strings[0]);
            String rssFeed = downloadXML(strings[0]);
            if (rssFeed == null) {
                Log.e(TAG, "doInBackground: Error downloading");
            }
            return rssFeed;
        }

        private String downloadXML(String urlPath) {
            StringBuilder xmlResult = new StringBuilder();

            try {
                URL url = new URL(urlPath);
                HttpURLConnection connection = (HttpURLConnection) url.openConnection();
                int response = connection.getResponseCode();
//                Log.d(TAG, "downloadXML: The response code was " + response);
//                InputStream inputStream = connection.getInputStream();
//                InputStreamReader inputStreamReader = new InputStreamReader(inputStream);
//                BufferedReader reader = new BufferedReader(inputStreamReader);
                BufferedReader reader = new BufferedReader(new InputStreamReader(connection.getInputStream()));

                int charsRead;
                char[] inputBuffer = new char[500];
                while (true) {
                    charsRead = reader.read(inputBuffer);
                    if (charsRead < 0) {
                        break;
                    }
                    if (charsRead > 0) {
                        xmlResult.append(String.copyValueOf(inputBuffer, 0, charsRead));
                    }
                }
                reader.close();

                return xmlResult.toString();
            } catch (MalformedURLException e) {
                Log.e(TAG, "downloadXML: Invalid URL " + e.getMessage());
            } catch (IOException e) {
                Log.e(TAG, "downloadXML: IO Exception reading data: " + e.getMessage());
            } catch (SecurityException e) {
                Log.e(TAG, "downloadXML: Security Exception.  Needs permission? " + e.getMessage());
//                e.printStackTrace();
            }

            return null;
        }
    }
}