RedditSubredditHistory.java

/*******************************************************************************
 * This file is part of RedReader.
 *
 * RedReader is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * RedReader is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with RedReader.  If not, see <http://www.gnu.org/licenses/>.
 ******************************************************************************/

package org.quantumbadger.redreader.reddit;

import org.quantumbadger.redreader.account.RedditAccount;
import org.quantumbadger.redreader.common.Constants;
import org.quantumbadger.redreader.common.PrefsUtility;
import org.quantumbadger.redreader.reddit.things.SubredditCanonicalId;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;


// Keeps an in-memory list of all known subreddits per account
public class RedditSubredditHistory {

	private static final HashMap<RedditAccount, HashSet<SubredditCanonicalId>> SUBREDDITS
			= new HashMap<>();

	private static HashSet<SubredditCanonicalId> getForAccount(final RedditAccount account) {

		HashSet<SubredditCanonicalId> result = SUBREDDITS.get(account);

		if(result == null) {
			result = new HashSet<>(Constants.Reddit.DEFAULT_SUBREDDITS);
			result.addAll(PrefsUtility.pref_pinned_subreddits(false));
			SUBREDDITS.put(account, result);
		}

		return result;
	}

	public static synchronized void addSubreddit(
			final RedditAccount account,
			final SubredditCanonicalId id) {

		getForAccount(account).add(id);
	}

	public static synchronized void addSubreddits(
			final RedditAccount account,
			final Collection<SubredditCanonicalId> ids) {

		getForAccount(account).addAll(ids);
	}

	public static synchronized ArrayList<SubredditCanonicalId> getSubredditsSorted(
			final RedditAccount account) {

		final ArrayList<SubredditCanonicalId> result = new ArrayList<>(getForAccount(
				account));
		Collections.sort(result);
		return result;
	}
}