DaemonTask.java

/*
 *	This file is part of Transdroid <http://www.transdroid.org>
 *	
 *	Transdroid 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.
 *	
 *	Transdroid 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 Transdroid.  If not, see <http://www.gnu.org/licenses/>.
 *	
 */
package org.transdroid.daemon.task;

import android.os.Bundle;
import android.os.Parcel;
import android.os.Parcelable;

import org.transdroid.core.gui.log.Log;
import org.transdroid.daemon.Daemon;
import org.transdroid.daemon.DaemonMethod;
import org.transdroid.daemon.IDaemonAdapter;
import org.transdroid.daemon.Torrent;

/**
 * A daemon task represents some action that needs to be performed on the server daemon. It has no capabilities on
 * itself; these are marshaled to the daemon adapter. Therefore all needed info (the parameters) needs to be added to
 * the extras bundle.
 * <p/>
 * To help create these tasks and there data, each possible daemon method is created using a task-specific separate
 * class with a create() method.
 * <p/>
 * This class is Parcelable so it can be persisted in between an Activity breakdown and recreation.
 * @author erickok
 */
public class DaemonTask implements Parcelable {

	public static final Parcelable.Creator<DaemonTask> CREATOR = new Parcelable.Creator<DaemonTask>() {
		public DaemonTask createFromParcel(Parcel in) {
			return new DaemonTask(in);
		}

		public DaemonTask[] newArray(int size) {
			return new DaemonTask[size];
		}
	};
	protected final DaemonMethod method;
	protected final Torrent targetTorrent;
	protected final Bundle extras;
	protected IDaemonAdapter adapter;

	private DaemonTask(Parcel in) {
		this.method = DaemonMethod.getStatus(in.readInt());
		this.targetTorrent = in.readParcelable(Torrent.class.getClassLoader());
		this.extras = in.readBundle();
	}

	protected DaemonTask(IDaemonAdapter adapter, DaemonMethod method, Torrent targetTorrent, Bundle extras) {
		this.adapter = adapter;
		this.method = method;
		this.targetTorrent = targetTorrent;
		if (extras == null) {
			this.extras = new Bundle();
		} else {
			this.extras = extras;
		}
	}

	/**
	 * Execute the task on the appropriate daemon adapter
	 * @param log The logger to use when writing exceptions and debug information
	 */
	public DaemonTaskResult execute(Log log) {
		return adapter.executeTask(log, this);
	}

	public DaemonMethod getMethod() {
		return method;
	}

	public Daemon getAdapterType() {
		return this.adapter.getType();
	}

	public Torrent getTargetTorrent() {
		return targetTorrent;
	}

	public Bundle getExtras() {
		return extras;
	}

	@Override
	public int describeContents() {
		return 0;
	}

	@Override
	public void writeToParcel(Parcel dest, int flags) {
		dest.writeInt(method.getCode());
		dest.writeParcelable(targetTorrent, 0);
		dest.writeBundle(extras);
	}

	/**
	 * Returns a readable description of this task in the form 'MethodName on AdapterName with TorrentName and
	 * AllExtras'
	 */
	public String toString() {
		return method.toString() + (adapter == null ? "" : " on " + adapter.getType()) +
				(targetTorrent != null || extras != null ? " with " : "") +
				(targetTorrent == null ? "" : targetTorrent.toString() + (extras != null ? " and " : "")) +
				(extras == null ? "" : extras.toString());
	}

}