GeoTiffElevationService.h

/*--------------------------------------------------------------------------------------------
Copyright (c) 2020, NDEVR LLC
tyler.parke@ndevr.org
  __    __   ____     _____ __     __  _______
 |  \  |  | |  __ \  |  ___|\ \   / / |   __  \
 |   \ |  | | |  \ \ | |___  \ \ / /  |  |__)  |
 |  . \|  | | |__/ / | |___   \ V /   |   _   /
 |  |\    |_|_____/__|_____|___\_/____|  | \  \
 |__| \__________________________________|  \__\
 
Subject to the terms of the Enterprise+ Agreement, NDEVR hereby grants
Licensee a limited, non-exclusive, non-transferable, royalty-free license
(without the right to sublicense) to use the API solely for the purpose of
Licensee's internal development efforts to develop applications for which
the API was provided.
 
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
 
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.
 
Library: GeoTiffElevation
File: GeoTiffElevationService
Included in API: True
Author(s): Tyler Parke
 *-----------------------------------------------------------------------------------------**/
#pragma once
#include "Design/Headers/ElevationService.h"
#include "TIFImageHandler/Headers/GeoTiffFactory.h"
#include "Base/Headers/Dictionary.h"
#include "Base/Headers/File.h"
#include "Base/Headers/RWLock.h"
#include <QObject>
struct tiff;
typedef struct tiff TIFF;
 
namespace NDEVR
{
    class ItemDownloader;
    struct TileKey
    {
        sint04 lat = Constant<sint04>::Invalid; 
        sint04 lon = Constant<sint04>::Invalid; 
        bool operator==(const TileKey& other) const
        {
            return lat == other.lat && lon == other.lon;
        }
        bool operator!=(const TileKey& other) const
        {
            return !operator==(other);
        }
    };
}
namespace std
{
    template<>
    struct hash<TileKey>
    {
        size_t operator()(const TileKey& key) const
        {
            return hash<int>()(key.lat) ^ (hash<int>()(key.lon) << 16);
        }
    };
}
namespace NDEVR
{
    struct CachedTile
    {
        GeoTiffInfo info;               
        TIFF* tif_handle = nullptr;     
        File file_path;                 
 
        uint04 band_index = 0;          
        bool is_tiled = false;          
        uint04 tile_width = 0;          
        uint04 tile_height = 0;         
        uint04 scanline_bytes = 0;      
 
        Buffer<uint01> read_buf;        
 
        uint04 cached_tile_ox = Constant<uint04>::Max;      
        uint04 cached_tile_oy = Constant<uint04>::Max;      
        uint04 cached_scanline_row = Constant<uint04>::Max; 
    };

    class GeoTiffElevationService : public QObject, public ElevationService
    {
    public:
        GeoTiffElevationService();
        ~GeoTiffElevationService();
        static void Initialize();
        virtual void postRequest(const ElevationRequest& request) override;

        static TileKey TileKeyForCoord(fltp08 lat, fltp08 lon);
        Buffer<TileKey> requiredTiles(const ElevationRequest& request);
        String tileUrl(const TileKey& key) const;
        File tileCachePath(const TileKey& key) const;
        String tileName(const TileKey& key) const;
    protected:
        void processRequest(ElevationRequest request);
        void downloadTile(const TileKey& key, LogPtr& log);
        void onTileDownloadedSlot(const TileKey& key);
        void onTileDownloadFailedSlot(const TileKey& key);
        bool loadTileFromDisk(const TileKey& key);
        void checkAndResolve(const UUID& request_id);
        void resolveRequest(ElevationRequest& request);

        fltp08 sampleElevation(CachedTile& tile, fltp08 lat, fltp08 lon);
    protected:
        Dictionary<TileKey, ItemDownloader*> m_active_downloads;        
        Dictionary<TileKey, CachedTile> m_loaded_tiles;             
        Dictionary<TileKey, bool> m_unavailable_tiles;              
        Dictionary<TileKey, Buffer<UUID>> m_pending_tile_downloads; 
        Dictionary<UUID, ElevationRequest> m_pending_requests;      
        Dictionary<UUID, Buffer<TileKey>> m_request_tiles;          
        RWLock m_lock;                                              
        File m_cache_dir;                                           
    };
}