/***************************************************************************
    qgsrasterdataprovider.h - DataProvider Interface for raster layers
     --------------------------------------
    Date                 : Mar 11, 2005
    Copyright            : (C) 2005 by Brendan Morley
    email                : morb at ozemail dot com dot au
 ***************************************************************************/

/***************************************************************************
 *                                                                         *
 *   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; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 ***************************************************************************/
/* $Id: qgsrasterdataprovider.h 12276 2009-11-28 17:07:29Z jef $ */

/* Thank you to Marco Hugentobler for the original vector DataProvider */

#ifndef QGSRASTERDATAPROVIDER_H
#define QGSRASTERDATAPROVIDER_H


#include "qgsdataprovider.h"

class QImage;
class QgsPoint;

/** \ingroup core
 * Base class for raster data providers.
 *
 *  \note  This class has been copied and pasted from
 *         QgsVectorDataProvider, and does not yet make
 *         sense for Raster layers.
 */

class CORE_EXPORT QgsRasterDataProvider : public QgsDataProvider
{

    Q_OBJECT

  public:

    //! If you add to this, please also add to capabilitiesString()
    enum Capability
    {
      NoCapabilities =              0,
      Identify =                    1
//      Capability2 =           1 <<  1, etc
    };


    QgsRasterDataProvider();

    QgsRasterDataProvider( QString const & uri );

    virtual ~QgsRasterDataProvider() {};


    /**
     * Add the list of WMS layer names to be rendered by this server
     */
    virtual void addLayers( QStringList const & layers,
                            QStringList  const & styles = QStringList() ) = 0;

    //! get raster image encodings supported by (e.g.) the WMS Server, expressed as MIME types
    virtual QStringList supportedImageEncodings() = 0;

    /**
     * Get the image encoding (as a MIME type) used in the transfer from (e.g.) the WMS server
     */
    virtual QString imageEncoding() const = 0;

    /**
     * Set the image encoding (as a MIME type) used in the transfer from (e.g.) the WMS server
     */
    virtual void setImageEncoding( QString  const & mimeType ) = 0;

    /**
     * Set the image projection (in WMS CRS format) used in the transfer from (e.g.) the WMS server
     */
    virtual void setImageCrs( QString const & crs ) = 0;


    // TODO: Document this better.
    /** \brief   Renders the layer as an image
     */
    virtual QImage* draw( QgsRectangle  const & viewExtent, int pixelWidth, int pixelHeight ) = 0;

    /** Returns a bitmask containing the supported capabilities
        Note, some capabilities may change depending on whether
        a spatial filter is active on this provider, so it may
        be prudent to check this value per intended operation.
      */
    virtual int capabilities() const
    {
      return QgsRasterDataProvider::NoCapabilities;
    }

    /**
     *  Returns the above in friendly format.
     */
    QString capabilitiesString() const;


    // TODO: Get the supported formats by this provider

    // TODO: Get the file masks supported by this provider, suitable for feeding into the file open dialog box


    /**
     * Get metadata in a format suitable for feeding directly
     * into a subset of the GUI raster properties "Metadata" tab.
     */
    virtual QString metadata() = 0;

    /**
     * \brief Identify details from a server (e.g. WMS) from the last screen update
     *
     * \param point[in]  The pixel coordinate (as it was displayed locally on screen)
     *
     * \return  A text document containing the return from the WMS server
     *
     * \note WMS Servers prefer to receive coordinates in image space, therefore
     *       this function expects coordinates in that format.
     *
     * \note  The arbitraryness of the returned document is enforced by WMS standards
     *        up to at least v1.3.0
     */
    virtual QString identifyAsText( const QgsPoint& point ) = 0;

    /**
     * \brief   Returns the caption error text for the last error in this provider
     *
     * If an operation returns 0 (e.g. draw()), this function
     * returns the text of the error associated with the failure.
     * Interactive users of this provider can then, for example,
     * call a QMessageBox to display the contents.
     *
     */
    virtual QString lastErrorTitle() = 0;

    /**
     * \brief   Returns the verbose error text for the last error in this provider
     *
     * If an operation returns 0 (e.g. draw()), this function
     * returns the text of the error associated with the failure.
     * Interactive users of this provider can then, for example,
     * call a QMessageBox to display the contents.
     *
     */
    virtual QString lastError() = 0;

    /**Returns the dpi of the output device.
      @note: this method was added in version 1.2*/
    int dpi() const {return mDpi;}

    /**Sets the output device resolution.
      @note: this method was added in version 1.2*/
    void setDpi( int dpi ) {mDpi = dpi;}


  protected:
    /**Dots per intch. Extended WMS (e.g. QGIS mapserver) support DPI dependent output and therefore
    are suited for printing. A value of -1 means it has not been set
    @note: this member has been added in version 1.2*/
    int mDpi;

};

#endif
