/*
 * image.h
 *
 * Copyright (c) 2001, 2002, 2003 Frerich Raabe <raabe@kde.org>
 *
 * 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. For licensing and distribution details, check the
 * accompanying file 'COPYING'.
 */
#ifndef LIBRSS_IMAGE_H
#define LIBRSS_IMAGE_H

#include "global.h"

#include <qobject.h>

class QDomNode;

namespace KIO
{
	class Job;
}
class KURL;

namespace RSS
{
	/**
	 * Represents an image as stored in a RSS file. You don't have to
	 * instantiate one of these yourself, the common way to access instances
	 * is via Document::image().
	 * @see Document::image()
	 */
	class Image : public QObject
	{
		Q_OBJECT
		public:
			/**
			 * Default constructor.
			 */
			Image();
		
			/**
			 * Copy constructor.
			 * @param other The Image object to copy.
			 */
			Image(const Image &other);

			/**
			 * Constructs an Image from a piece of RSS markup.
			 * @param node A QDomNode which references the DOM leaf to be used
			 * for constructing the Image.
			 */
			Image(const QDomNode &node);
			
			/**
			 * Assignment operator.
			 * @param other The Image object to clone.
			 * @return A reference to the cloned Image object.
			 */
			Image &operator=(const Image &other);

			/**
			 * Compares two images. Two images are considered identical if
			 * their properties (title, description, link etc.) are identical.
			 * Note that this does not include the actual pixmap data!
			 * @param other The image to compare with.
			 * @return Whether the two images are equal.
			 */
			bool operator==(const Image &other) const;

			/**
			 * Convenience method. Simply calls !operator==().
			 * @param other The image to compared with.
			 * @return Whether the two images are unequal.
			 */
			bool operator!=(const Image &other) const { return !operator==(other); }
			
			/**
			 * Destructor.
			 */
			virtual ~Image();

			/**
			 * RSS 0.90 and upwards
			 * @return The 'caption' of this image, or QString::null if no
			 * caption is available.
			 */
			QString title() const;

			/**
			 * RSS 0.90 and upwards
			 * @return The URL pointing to the file containing the graphic
			 * data (GIF, JPEG or PNG format), or an empty KURL if no URL
			 * is available. You can use getPixmap() and gotPixmap() to have
			 * the Image download the pixmap data itself.
			 * Note that the RSS 0.91 Specification dictates that URLs not
			 * starting with "http://" or "ftp://" are considered invalid.
			 */
			const KURL &url() const;

			/**
			 * RSS 0.90 and upwards
			 * @return A link to some resource, or an empty KURL of no link is
			 * available. Clicking on the image should lead the user to the
			 * resource referenced by this URL.
			 * Note that the RSS 0.91 Specification dictates that URLs not
			 * starting with "http://" or "ftp://" are considered invalid.
			 */
			const KURL &link() const;
			
			/**
			 * RSS 0.91 and upwards
			 * @return A description of what this picture shows, or
			 * QString::null if no description is available. Useful for
			 * people who deactivated images but want or need to know what is
			 * shown.
			 */
			QString description() const;

			/**
			 * RSS 0.91 and upwards
			 * @return The height in pixels as reported by the news site, the
			 * default value is 31 pixels. The RSS 0.91 Specification requires
			 * this value to be between 1 and 400.
			 * '0' if this information isn't available. This is merely provided
			 * for completeness, you should not rely on this value but rather
			 * check what height the QPixmap as returned by gotPixmap()
			 * reports.
			 */
			unsigned int height() const;
			
			/**
			 * RSS 0.91 and upwards
			 * @return The width in pixels as reported by the news site, the
			 * default value is 88 pixels. The RSS 0.91 Specification requires
			 * this value to be between 1 and 144.
			 * This is merely provided for completeness, you should not rely
			 * on this value but rather check what width the QPixmap as
			 * returned by gotPixmap() reports.
			 */
			unsigned int width() const;

			/**
			 * Makes the image download the image data as referenced by the
			 * URL returned by url(). You have to connect to the signal
			 * gotPixmap() first and then call getPixmap().
			 */
			void getPixmap();

		signals:
			/**
			 * Emitted when this Image is done downloading the actual graphics
			 * data as referenced by the URL returned by url(). You can trigger
			 * this download by calling getPixmap().
			 * @param pixmap The pixmap as constructed from the data referenced
			 * by the URL returned by link().
			 */
			void gotPixmap(const QPixmap &pixmap);

		private slots:
			void slotData(KIO::Job *job, const QByteArray &data);
			void slotResult(KIO::Job *job);

		private:
			struct Private;
			Private *d;
	};
}

#endif // LIBRSS_IMAGE_H
// vim: noet:ts=4
