TopGamesFragment.java

package com.boardgamegeek.ui;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.widget.ContentLoadingProgressBar;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import com.boardgamegeek.R;
import com.boardgamegeek.model.TopGame;
import com.boardgamegeek.ui.adapter.TopGamesAdapter;
import com.boardgamegeek.util.AnimationUtils;

import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.nodes.Element;
import org.jsoup.select.Elements;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import butterknife.BindView;
import butterknife.ButterKnife;
import butterknife.Unbinder;
import rx.Single;
import rx.SingleSubscriber;
import rx.android.schedulers.AndroidSchedulers;
import rx.schedulers.Schedulers;
import timber.log.Timber;

public class TopGamesFragment extends Fragment {
	Unbinder unbinder;
	TopGamesAdapter adapter;
	@BindView(android.R.id.progress) ContentLoadingProgressBar progressView;
	@BindView(android.R.id.empty) TextView emptyView;
	@BindView(android.R.id.list) RecyclerView recyclerView;

	@Override
	public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
		View rootView = inflater.inflate(R.layout.fragment_top_games, container, false);
		unbinder = ButterKnife.bind(this, rootView);
		setUpRecyclerView();
		loadTopGames();
		return rootView;
	}

	private void setUpRecyclerView() {
		recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
		recyclerView.setHasFixedSize(true);
	}

	private void loadTopGames() {
		Single
			.create(new Single.OnSubscribe<List<TopGame>>() {
				@Override
				public void call(SingleSubscriber<? super List<TopGame>> singleSubscriber) {
					try {
						List<TopGame> topGames = findTopGames();
						singleSubscriber.onSuccess(topGames);
					} catch (Throwable t) {
						singleSubscriber.onError(t);
					}
				}
			})
			.subscribeOn(Schedulers.io())
			.observeOn(AndroidSchedulers.mainThread())
			.subscribe(new SingleSubscriber<List<TopGame>>() {
				@Override
				public void onSuccess(List<TopGame> topGames) {
					if (topGames.isEmpty()) {
						AnimationUtils.fadeIn(emptyView);
					} else {
						adapter = new TopGamesAdapter(topGames);
						recyclerView.setAdapter(adapter);
						AnimationUtils.fadeIn(getActivity(), recyclerView, isResumed());
					}
					progressView.hide();
				}

				@Override
				public void onError(Throwable error) {
					Timber.e(error, "Error loading top games");
					if (isAdded()) {
						emptyView.setText(getString(R.string.empty_http_error, error.getLocalizedMessage()));
					}
					AnimationUtils.fadeIn(emptyView);
					progressView.hide();
				}
			});
	}

	private List<TopGame> findTopGames() throws IOException {
		List<TopGame> topGames = new ArrayList<>();

		int rank = 1;
		Document doc = Jsoup.connect("https://www.boardgamegeek.com/browse/boardgame").get();
		Elements gameElements = doc.select("td.collection_thumbnail");
		for (Element element : gameElements) {
			TopGame game = new TopGame();
			Element link = element.getElementsByTag("a").first();
			game.id = getGameIdFromLink(link.attr("href"));
			game.rank = rank;
			game.yearPublished = 0;
			game.thumbnailUrl = link.child(0).attr("src").replaceAll("_mt\\.", "_t.");

			Element gameNameElement = element.parent().select(".collection_objectname").get(0).child(1);
			game.name = gameNameElement.child(0).text();
			String yearPublishedText = gameNameElement.child(1).text();
			game.yearPublished = Integer.parseInt(yearPublishedText.substring(1, yearPublishedText.length() - 1));

			topGames.add(game);
			rank++;
		}
		return topGames;
	}

	private int getGameIdFromLink(String href) {
		int boardGameIndex = href.indexOf("/boardgame/");
		String afterBoardGameString;
		if (boardGameIndex != -1) {
			afterBoardGameString = href.substring(boardGameIndex + 11);
		} else {
			int boardGameExpansionIndex = href.indexOf("/boardgameexpansion/");
			afterBoardGameString = href.substring(boardGameExpansionIndex + 20);
		}
		int slashIndex = afterBoardGameString.indexOf("/");
		return Integer.parseInt(afterBoardGameString.substring(0, slashIndex));
	}
}