QuranAppUtils.java

package com.quran.labs.androidquran.util;

import android.text.TextUtils;

import com.quran.labs.androidquran.data.Constants;
import com.quran.labs.androidquran.data.QuranInfo;
import com.quran.labs.androidquran.data.SuraAyah;

import org.json.JSONObject;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.concurrent.Callable;

import io.reactivex.Single;
import io.reactivex.schedulers.Schedulers;
import timber.log.Timber;

public class QuranAppUtils {

  public static Single<String> getQuranAppUrlObservable(final String key,
      final SuraAyah start, final SuraAyah end) {
    return Single.fromCallable(new Callable<String>() {
      @Override
      public String call() throws Exception {
        int sura = start.sura;
        int startAyah = start.ayah;
        // quranapp only supports sharing within a sura
        int endAyah = end.sura == start.sura ? end.ayah : QuranInfo.getNumAyahs(start.sura);
        return QuranAppUtils.getQuranAppUrl(key, sura, startAyah, endAyah);
      }
    }).subscribeOn(Schedulers.io());
  }

  private static String getQuranAppUrl(String key, int sura, Integer startAyah, Integer endAyah) {
    String url = null;
    String fallbackUrl = null;
    try {
      Map<String, String> params = new HashMap<String, String>();
      params.put("surah", sura + "");
      fallbackUrl = Constants.QURAN_APP_BASE + sura;
      if (startAyah != null) {
        params.put("start_ayah", startAyah.toString());
        fallbackUrl += "/" + startAyah;
        if (endAyah != null) {
          params.put("end_ayah", endAyah.toString());
          fallbackUrl += "-" + endAyah;
        } else {
          params.put("end_ayah", startAyah.toString());
        }
      }
      params.put("key", key);
      String result = getQuranAppUrl(params);
      if (!TextUtils.isEmpty(result)) {
        JSONObject json = new JSONObject(result);
        url = json.getString("url");
      }
    } catch (Exception e) {
      Timber.d(e, "error getting QuranApp url");
    }

    Timber.d("got back %s and fallback %s", url, fallbackUrl);
    return TextUtils.isEmpty(url) ? fallbackUrl : url;
  }

  private static String getQuranAppUrl(Map<String, String> params)
      throws IOException {
    URL url = null;
    try {
      url = new URL(Constants.QURAN_APP_ENDPOINT);
    } catch (MalformedURLException me) {
      // ignore
    }

    StringBuilder builder = new StringBuilder();
    Iterator<Map.Entry<String, String>> iterator =
        params.entrySet().iterator();
    while (iterator.hasNext()) {
      Map.Entry<String, String> item = iterator.next();
      builder.append(item.getKey()).append("=").append(item.getValue());
      if (iterator.hasNext()) {
        builder.append('&');
      }
    }

    String result = "";
    String body = builder.toString();
    byte[] bytes = body.getBytes();
    HttpURLConnection conn = null;
    try {
      // TODO: use OkHttp
      conn = (HttpURLConnection) url.openConnection();
      conn.setReadTimeout(10000);
      conn.setConnectTimeout(15000);
      conn.setDoOutput(true);
      conn.setDoInput(true);
      conn.setUseCaches(false);
      conn.setFixedLengthStreamingMode(bytes.length);
      conn.setRequestMethod("POST");
      conn.setRequestProperty("Content-Type",
          "application/x-www-form-urlencoded;charset=UTF-8");

      // post the request
      OutputStream out = conn.getOutputStream();
      out.write(bytes);
      out.close();

      // handle the response
      BufferedReader reader =
          new BufferedReader(new InputStreamReader(
              conn.getInputStream(), "UTF-8"));

      String line;
      while ((line = reader.readLine()) != null) {
        result += line;
      }

      try {
        reader.close();
      } catch (Exception e) {
        // ignore
      }
    } finally {
      if (conn != null) {
        conn.disconnect();
      }
    }

    return result;
  }
}