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       1                 :            : /***************************************************************************
       2                 :            :   qgsmbtiles.h
       3                 :            :   --------------------------------------
       4                 :            :   Date                 : January 2020
       5                 :            :   Copyright            : (C) 2020 by Martin Dobias
       6                 :            :   Email                : wonder dot sk at gmail dot com
       7                 :            :  ***************************************************************************
       8                 :            :  *                                                                         *
       9                 :            :  *   This program is free software; you can redistribute it and/or modify  *
      10                 :            :  *   it under the terms of the GNU General Public License as published by  *
      11                 :            :  *   the Free Software Foundation; either version 2 of the License, or     *
      12                 :            :  *   (at your option) any later version.                                   *
      13                 :            :  *                                                                         *
      14                 :            :  ***************************************************************************/
      15                 :            : 
      16                 :            : #ifndef QGSMBTILES_H
      17                 :            : #define QGSMBTILES_H
      18                 :            : 
      19                 :            : #include "qgis_core.h"
      20                 :            : 
      21                 :            : #include "sqlite3.h"
      22                 :            : #include "qgssqliteutils.h"
      23                 :            : 
      24                 :            : #define SIP_NO_FILE
      25                 :            : 
      26                 :            : class QImage;
      27                 :            : class QgsRectangle;
      28                 :            : 
      29                 :            : /**
      30                 :            :  * \ingroup core
      31                 :            :  * \brief Utility class for reading and writing MBTiles files (which are SQLite3 databases).
      32                 :            :  *
      33                 :            :  * See the specification for more details:
      34                 :            :  * https://github.com/mapbox/mbtiles-spec/blob/master/1.3/spec.md
      35                 :            :  *
      36                 :            :  * \since QGIS 3.14
      37                 :            :  */
      38                 :          0 : class CORE_EXPORT QgsMbTiles
      39                 :            : {
      40                 :            :   public:
      41                 :            :     //! Constructs MBTiles reader (but it does not open the file yet)
      42                 :            :     explicit QgsMbTiles( const QString &filename );
      43                 :            : 
      44                 :            :     //! Tries to open the file, returns true on success
      45                 :            :     bool open();
      46                 :            : 
      47                 :            :     //! Returns whether the MBTiles file is currently opened
      48                 :            :     bool isOpen() const;
      49                 :            : 
      50                 :            :     /**
      51                 :            :      * Creates a new MBTiles file and initializes it with metadata and tiles tables.
      52                 :            :      * It is up to the caller to set appropriate metadata entries and add tiles afterwards.
      53                 :            :      * Returns TRUE on success. If the file exists already, returns FALSE.
      54                 :            :      */
      55                 :            :     bool create();
      56                 :            : 
      57                 :            :     //! Requests metadata value for the given key
      58                 :            :     QString metadataValue( const QString &key );
      59                 :            : 
      60                 :            :     /**
      61                 :            :      * Sets metadata value for the given key. Does not overwrite existing entries.
      62                 :            :      * \note the database has to be opened in read-write mode (currently only when opened with create()
      63                 :            :      */
      64                 :            :     void setMetadataValue( const QString &key, const QString &value );
      65                 :            : 
      66                 :            :     //! Returns bounding box from metadata, given in WGS 84 (if available)
      67                 :            :     QgsRectangle extent();
      68                 :            : 
      69                 :            :     //! Returns raw tile data for given tile
      70                 :            :     QByteArray tileData( int z, int x, int y );
      71                 :            : 
      72                 :            :     //! Returns tile decoded as a raster image (if stored in a known format like JPG or PNG)
      73                 :            :     QImage tileDataAsImage( int z, int x, int y );
      74                 :            : 
      75                 :            :     /**
      76                 :            :      * Adds tile data for the given tile coordinates. Does not overwrite existing entries.
      77                 :            :      * \note the database has to be opened in read-write mode (currently only when opened with create()
      78                 :            :      */
      79                 :            :     void setTileData( int z, int x, int y, const QByteArray &data );
      80                 :            : 
      81                 :            :     //! Decodes gzip byte stream, returns true on success. Useful for reading vector tiles.
      82                 :            :     static bool decodeGzip( const QByteArray &bytesIn, QByteArray &bytesOut );
      83                 :            :     //! Encodes gzip byte stream, returns true on success. Useful for writing vector tiles.
      84                 :            :     static bool encodeGzip( const QByteArray &bytesIn, QByteArray &bytesOut );
      85                 :            : 
      86                 :            :   private:
      87                 :            :     QString mFilename;
      88                 :            :     sqlite3_database_unique_ptr mDatabase;
      89                 :            : };
      90                 :            : 
      91                 :            : 
      92                 :            : #endif // QGSMBTILES_H