/*
 * PS3 Media Server, for streaming any medias to your PS3.
 * Copyright (C) 2008  A.Brochard
 *
 * This program 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; version 2
 * of the License only.
 *
 * This program 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 this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */
package net.pms.dlna;

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

import org.apache.commons.lang.StringUtils;
import org.jdom.Content;
import org.jdom.Element;

import com.sun.syndication.feed.synd.SyndCategory;
import com.sun.syndication.feed.synd.SyndEnclosure;
import com.sun.syndication.feed.synd.SyndEntry;
import com.sun.syndication.feed.synd.SyndFeed;
import com.sun.syndication.io.SyndFeedInput;
import com.sun.syndication.io.XmlReader;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * TODO: Change all instance variables to private. For backwards compatibility
 * with external plugin code the variables have all been marked as deprecated
 * instead of changed to private, but this will surely change in the future.
 * When everything has been changed to private, the deprecated note can be
 * removed.
 */
public class Feed extends DLNAResource {
	private static final Logger logger = LoggerFactory.getLogger(Feed.class);

	/**
	 * @deprecated Use standard getter and setter to access this variable.
	 */
	@Deprecated
	protected String name;

	/**
	 * @deprecated Use standard getter and setter to access this variable.
	 */
	@Deprecated
	protected String url;

	/**
	 * @deprecated Use standard getter and setter to access this variable.
	 */
	@Deprecated
	protected String tempItemTitle;

	/**
	 * @deprecated Use standard getter and setter to access this variable.
	 */
	@Deprecated
	protected String tempItemLink;

	/**
	 * @deprecated Use standard getter and setter to access this variable.
	 */
	@Deprecated
	protected String tempFeedLink;

	/**
	 * @deprecated Use standard getter and setter to access this variable.
	 */
	@Deprecated
	protected String tempCategory;

	/**
	 * @deprecated Use standard getter and setter to access this variable.
	 */
	@Deprecated
	protected String tempItemThumbURL;

	@Override
	public void resolve() {
		super.resolve();
		try {
			parse();
		} catch (Exception e) {
			logger.error("Error in parsing stream: " + url, e);
		}
	}

	public Feed(String name, String url, int type) {
		super(type);
		setUrl(url);
		setName(name);
	}

	@SuppressWarnings("unchecked")
	public void parse() throws Exception {
		SyndFeedInput input = new SyndFeedInput();
		byte b[] = downloadAndSendBinary(url);
		if (b != null) {
			String content = new String(b, "UTF-8");
			content = stripNonValidXMLCharacters(content);
			SyndFeed feed = input.build(new XmlReader(new ByteArrayInputStream(b)));
			setName(feed.getTitle());
			if (feed.getCategories() != null && feed.getCategories().size() > 0) {
				SyndCategory category = (SyndCategory) feed.getCategories().get(0);
				setTempCategory(category.getName());
			}
			List<SyndEntry> entries = feed.getEntries();
			for (SyndEntry entry : entries) {
				setTempItemTitle(entry.getTitle());
				setTempItemLink(entry.getLink());
				setTempFeedLink(entry.getUri());
				setTempItemThumbURL(null);

				ArrayList<Element> elements = (ArrayList<Element>) entry.getForeignMarkup();
				for (Element elt : elements) {
					if ("group".equals(elt.getName()) && "media".equals(elt.getNamespacePrefix())) {
						List<Content> subElts = elt.getContent();
						for (Content subelt : subElts) {
							if (subelt instanceof Element) {
								parseElement((Element) subelt, false);
							}
						}
					}
					parseElement(elt, true);
				}
				List<SyndEnclosure> enclosures = entry.getEnclosures();
				for (SyndEnclosure enc : enclosures) {
					if (StringUtils.isNotBlank(enc.getUrl())) {
						setTempItemLink(enc.getUrl());
					}
				}
				manageItem();
			}
		}
		setLastmodified(System.currentTimeMillis());
	}

	@SuppressWarnings("unchecked")
	private void parseElement(Element elt, boolean parseLink) {
		if ("content".equals(elt.getName()) && "media".equals(elt.getNamespacePrefix())) {
			if (parseLink) {
				setTempItemLink(elt.getAttribute("url").getValue());
			}
			List<Content> subElts = elt.getContent();
			for (Content subelt : subElts) {
				if (subelt instanceof Element) {
					parseElement((Element) subelt, false);
				}
			}
		}
		if ("thumbnail".equals(elt.getName()) && "media".equals(elt.getNamespacePrefix())) {
			if (getTempItemThumbURL() == null) {
				setTempItemThumbURL(elt.getAttribute("url").getValue());
			}
		}
		if ("image".equals(elt.getName()) && "exInfo".equals(elt.getNamespacePrefix())) {
			if (getTempItemThumbURL() == null) {
				setTempItemThumbURL(elt.getValue());
			}
		}
	}

	public InputStream getInputStream() throws IOException {
		return null;
	}

	public String getName() {
		return name;
	}

	public boolean isFolder() {
		return true;
	}

	public long length() {
		return 0;
	}

	public long lastModified() {
		return 0;
	}

	@Override
	public String getSystemName() {
		return url;
	}

	@Override
	public boolean isValid() {
		return true;
	}

	protected void manageItem() {
		FeedItem fi = new FeedItem(getTempItemTitle(), getTempItemLink(), getTempItemThumbURL(), null, getSpecificType());
		addChild(fi);
	}

	@Override
	public boolean isRefreshNeeded() {
	    return (System.currentTimeMillis() - getLastmodified() > 3600000);
	}

	@Override
	public void doRefreshChildren() {
		try {
			getChildren().clear();
			parse();
		} catch (Exception e) {
			logger.error("Error in parsing stream: " + url, e);
		}
	}

	/**
	 * This method ensures that the output String has only
	 * valid XML unicode characters as specified by the
	 * XML 1.0 standard. For reference, please see
	 * <a href="http://www.w3.org/TR/2000/REC-xml-20001006#NT-Char">the
	 * standard</a>. This method will return an empty
	 * String if the input is null or empty.
	 *
	 * @param in The String whose non-valid characters we want to remove.
	 * @return The in String, stripped of non-valid characters.
	 */
	private String stripNonValidXMLCharacters(String in) {
		StringBuilder out = new StringBuilder(); // Used to hold the output.
		char current; // Used to reference the current character.

		if (in == null || ("".equals(in))) {
			return ""; // vacancy test.
		}
		for (int i = 0; i < in.length(); i++) {
			current = in.charAt(i); // NOTE: No IndexOutOfBoundsException caught here; it should not happen.
			if ((current == 0x9)
				|| (current == 0xA)
				|| (current == 0xD)
				|| ((current >= 0x20) && (current <= 0xD7FF))
				|| ((current >= 0xE000) && (current <= 0xFFFD))
				|| ((current >= 0x10000) && (current <= 0x10FFFF))) {
				out.append(current);
			}
		}
		return out.toString();
	}

	/**
	 * @return the url
	 * @since 1.50
	 */
	protected String getUrl() {
		return url;
	}

	/**
	 * @param url the url to set
	 * @since 1.50
	 */
	protected void setUrl(String url) {
		this.url = url;
	}

	/**
	 * @return the tempItemTitle
	 * @since 1.50
	 */
	protected String getTempItemTitle() {
		return tempItemTitle;
	}

	/**
	 * @param tempItemTitle the tempItemTitle to set
	 * @since 1.50
	 */
	protected void setTempItemTitle(String tempItemTitle) {
		this.tempItemTitle = tempItemTitle;
	}

	/**
	 * @return the tempItemLink
	 * @since 1.50
	 */
	protected String getTempItemLink() {
		return tempItemLink;
	}

	/**
	 * @param tempItemLink the tempItemLink to set
	 * @since 1.50
	 */
	protected void setTempItemLink(String tempItemLink) {
		this.tempItemLink = tempItemLink;
	}

	/**
	 * @return the tempFeedLink
	 * @since 1.50
	 */
	protected String getTempFeedLink() {
		return tempFeedLink;
	}

	/**
	 * @param tempFeedLink the tempFeedLink to set
	 * @since 1.50
	 */
	protected void setTempFeedLink(String tempFeedLink) {
		this.tempFeedLink = tempFeedLink;
	}

	/**
	 * @return the tempCategory
	 * @since 1.50
	 */
	protected String getTempCategory() {
		return tempCategory;
	}

	/**
	 * @param tempCategory the tempCategory to set
	 * @since 1.50
	 */
	protected void setTempCategory(String tempCategory) {
		this.tempCategory = tempCategory;
	}

	/**
	 * @return the tempItemThumbURL
	 * @since 1.50
	 */
	protected String getTempItemThumbURL() {
		return tempItemThumbURL;
	}

	/**
	 * @param tempItemThumbURL the tempItemThumbURL to set
	 * @since 1.50
	 */
	protected void setTempItemThumbURL(String tempItemThumbURL) {
		this.tempItemThumbURL = tempItemThumbURL;
	}

	/**
	 * @param name the name to set
	 * @since 1.50
	 */
	protected void setName(String name) {
		this.name = name;
	}
}