mapnik/plugins/input/shape/shape.cpp

/*****************************************************************************
 * 
 * This file is part of Mapnik (c++ mapping toolkit)
 *
 * Copyright (C) 2006 Artem Pavlenko
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 *****************************************************************************/

#include <iostream>
#include <fstream>
#include <stdexcept>
#include <mapnik/geom_util.hpp>

// boost
#include <boost/version.hpp>
#include <boost/format.hpp>
#include <boost/algorithm/string.hpp>
#include <boost/filesystem/operations.hpp>


#include "shape_featureset.hpp"
#include "shape_index_featureset.hpp"
#include "shape.hpp"

DATASOURCE_PLUGIN(shape_datasource)

using mapnik::String;
using mapnik::Double;
using mapnik::Integer;
using mapnik::datasource_exception;
using mapnik::filter_in_box;
using mapnik::filter_at_point;
using mapnik::attribute_descriptor;

shape_datasource::shape_datasource(const parameters &params)
    : datasource (params),
      type_(datasource::Vector),
      file_length_(0),
      indexed_(false),
      desc_(*params.get<std::string>("type"), *params.get<std::string>("encoding","utf-8"))
{
    boost::optional<std::string> file = params.get<std::string>("file");
    if (!file) throw datasource_exception("missing <file> parameter");
      
    boost::optional<std::string> base = params.get<std::string>("base");
    if (base)
        shape_name_ = *base + "/" + *file;
    else
        shape_name_ = *file;

    boost::algorithm::ireplace_last(shape_name_,".shp","");
   
    if (!boost::filesystem::exists(shape_name_ + ".shp"))
    {
        throw datasource_exception("shapefile '" + shape_name_ + ".shp' does not exist");
    }

    if (boost::filesystem::is_directory(shape_name_ + ".shp"))
    {
        throw datasource_exception("shapefile '" + shape_name_ + ".shp' appears to be a directory not a file");
    }

    try
    {  
        shape_ = boost::shared_ptr<shape_io>(new shape_io(shape_name_));
        init(*shape_);
        for (int i=0;i<shape_->dbf().num_fields();++i)
        {
            field_descriptor const& fd=shape_->dbf().descriptor(i);
            std::string fld_name=fd.name_;
            switch (fd.type_)
            {
            case 'C':
            case 'D':
            case 'M':
            case 'L':
                desc_.add_descriptor(attribute_descriptor(fld_name, String));
                break;
            case 'N':
            case 'F':
            {
                if (fd.dec_>0)
                {   
                    desc_.add_descriptor(attribute_descriptor(fld_name,Double,false,8));
                }
                else
                {
                    desc_.add_descriptor(attribute_descriptor(fld_name,Integer,false,4));
                }
                break;
            }
            default:
#ifdef MAPNIK_DEBUG                
                std::clog << "unknown type "<<fd.type_<<"\n";
#endif 
                break;
            }
        }
    }
    catch (datasource_exception& ex)
    {
        std::clog<<ex.what()<<std::endl;
        throw;
    }
    catch (...)
    {
        std::clog << " got exception ... \n";
        throw;
    }
}

shape_datasource::~shape_datasource() {}

const std::string shape_datasource::name_="shape";

void  shape_datasource::init(shape_io& shape)
{
    //first read header from *.shp
    int file_code=shape.shp().read_xdr_integer();
    if (file_code!=9994)
    {
        //invalid file code
        throw datasource_exception((boost::format("wrong file code : %d") % file_code).str());
    }
    
    shape.shp().skip(5*4);
    file_length_=shape.shp().read_xdr_integer();
    int version=shape.shp().read_ndr_integer();
   
    if (version!=1000)
    {
        //invalid version number
        throw datasource_exception((boost::format("invalid version number: %d") % version).str());
    }
   
#ifdef MAPNIK_DEBUG
    int shape_type = shape.shp().read_ndr_integer();
#else
    shape.shp().skip(4);
#endif
   
    shape.shp().read_envelope(extent_);
   
#ifdef MAPNIK_DEBUG
    double zmin = shape.shp().read_double();
    double zmax = shape.shp().read_double();
    double mmin = shape.shp().read_double();
    double mmax = shape.shp().read_double();

    std::clog << "Z min/max " << zmin << "," << zmax << "\n";
    std::clog << "M min/max " << mmin << "," << mmax << "\n";
#else
    shape.shp().skip(4*8);
#endif

    // check if we have an index file around
    
    indexed_ = shape.has_index();
    //std::string index_name(shape_name_+".index");
    //std::ifstream file(index_name.c_str(),std::ios::in | std::ios::binary);
    //if (file)
    //{
    //    indexed_=true;
    //    file.close();
    //}
    //else
    //{
    //    std::clog << "### Notice: no .index file found for " + shape_name_ + ".shp, use the 'shapeindex' program to build an index for faster rendering\n";
    //}
    
#ifdef MAPNIK_DEBUG
    std::clog << extent_ << std::endl;
    std::clog << "file_length=" << file_length_ << std::endl;
    std::clog << "shape_type=" << shape_type << std::endl;
#endif

}

int shape_datasource::type() const
{
    return type_;
}

layer_descriptor shape_datasource::get_descriptor() const
{
    return desc_;
}

std::string shape_datasource::name()
{
    return name_;
}

featureset_ptr shape_datasource::features(const query& q) const
{
    filter_in_box filter(q.get_bbox());
    if (indexed_)
    {
        shape_->shp().seek(0);
        return featureset_ptr
            (new shape_index_featureset<filter_in_box>(filter,
                                                       *shape_,
                                                       q.property_names(),
                                                       desc_.get_encoding()));
    }
    else
    {
        return featureset_ptr
            (new shape_featureset<filter_in_box>(filter,
                                                 shape_name_,
                                                 q.property_names(),
                                                 desc_.get_encoding(),
                                                 file_length_));
    }
}

featureset_ptr shape_datasource::features_at_point(coord2d const& pt) const
{
    filter_at_point filter(pt);
    // collect all attribute names
    std::vector<attribute_descriptor> const& desc_vector = desc_.get_descriptors();
    std::vector<attribute_descriptor>::const_iterator itr = desc_vector.begin();
    std::vector<attribute_descriptor>::const_iterator end = desc_vector.end();
    std::set<std::string> names;
    
    while (itr != end)
    {    
        names.insert(itr->get_name());
        ++itr;
    }
    
    if (indexed_)
    {
        shape_->shp().seek(0);
        return featureset_ptr
            (new shape_index_featureset<filter_at_point>(filter,
                                                         *shape_,
                                                         names,
                                                         desc_.get_encoding()));
    }
    else
    {
        return featureset_ptr
            (new shape_featureset<filter_at_point>(filter,
                                                   shape_name_,
                                                   names,
                                                   desc_.get_encoding(),
                                                   file_length_));
    }
}

box2d<double> shape_datasource::envelope() const
{
    return extent_;
}