roi_util.cc

// -*- mode: c++; c-basic-offset:4 -*-
 
// This file is part of libdap, A C++ implementation of the OPeNDAP Data
// Access Protocol.
 
// Copyright (c) 2015 OPeNDAP, Inc.
// Author: James Gallagher <jgallagher@opendap.org>
//
// 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 Street, Fifth Floor, Boston, MA  02110-1301  USA
//
// You can contact OPeNDAP, Inc. at PO Box 112, Saunderstown, RI. 02874-0112.
 
#include "config.h"
 
#include <memory>
 
#include <libdap/BaseType.h>
#include <libdap/Structure.h>
#include <libdap/Array.h>
#include <libdap/Int32.h>
#include <libdap/Str.h>
 
#include <libdap/util.h>
 
#include "roi_util.h"
 
using namespace libdap;
 
namespace functions {

void roi_bbox_valid_slice(BaseType *btp)
{
    // we know it's a Structure * and it has one element because the test above passed
    if (btp->type() != dods_structure_c)
        throw Error("In function roi(): Expected an Array of Structures for the slice information.");
 
    Structure *slice = static_cast<Structure*>(btp);
 
    Constructor::Vars_iter i = slice->var_begin();
    if (i == slice->var_end() || (*i)->name() != "start" || (*i)->type() != dods_int32_c)
        throw Error("In function roi(): Could not find valid 'start' field in slice information");
 
    ++i;
    if (i == slice->var_end() || (*i)->name() != "stop" || (*i)->type() != dods_int32_c)
        throw Error("In function roi(): Could not find valid 'stop' field in slice information");
 
    ++i;
    if (i == slice->var_end() || (*i)->name() != "name" || (*i)->type() != dods_str_c)
        throw Error("In function roi(): Could not find valid 'name' field in slice information");
}

unsigned int roi_valid_bbox(BaseType *btp)
{
    if (!btp)
        throw InternalErr(__FILE__, __LINE__, "Function called with null slice array.");
 
    if (btp->type() != dods_array_c)
        throw Error("Function expected last argument to be a Bounding Box (i.e., an Array of Structures) (1).");
 
    Array *slices = static_cast<Array*>(btp);
    if (slices->dimensions() != 1)
        throw Error("Function expected last argument to be a Bounding Box (i.e., an Array of Structures) (2).");
 
    int rank = slices->dimension_size(slices->dim_begin());
    for (int i = 0; i < rank; ++i) {
        roi_bbox_valid_slice(slices->var(i));
    }
 
    return rank;
}

void roi_bbox_get_slice_data(Array *slices, unsigned int i, int &start, int &stop, string &name)
{
    BaseType *btp = slices->var(i);
 
    Structure *slice = static_cast<Structure*>(btp);
    Constructor::Vars_iter vi = slice->var_begin();
 
    start = static_cast<Int32*>(*vi++)->value();
    stop = static_cast<Int32*>(*vi++)->value();
    name = static_cast<Str*>(*vi++)->value();
}

Structure *roi_bbox_build_slice(unsigned int start_value, unsigned int stop_value, const string &dim_name)
{
    Structure *slice = new Structure("slice"); // This name is superfluous
 
    Int32 *start = new Int32("start");
    start->set_value(start_value);
    slice->add_var_nocopy(start);
 
    Int32 *stop = new Int32("stop");
    stop->set_value(stop_value);
    slice->add_var_nocopy(stop);
 
    Str *name = new Str("name");
    name->set_value(dim_name);
    slice->add_var_nocopy(name);
 
    slice->set_read_p(true);        // Sets all children too, as does set_send_p()
    slice->set_send_p(true);
 
    return slice;
}

unique_ptr<Array> roi_bbox_build_empty_bbox(unsigned int num_dim, const string &bbox_name)
{
    // Build the Structure and load it with the needed fields. The
    // Array instances will have the same fields, but each instance
    // will also be loaded with values.
    Structure *proto = new Structure(bbox_name);
    proto->add_var_nocopy(new Int32("start"));
    proto->add_var_nocopy(new Int32("stop"));
    proto->add_var_nocopy(new Str("name"));
    // Using auto_ptr and not unique_ptr because of OS/X 10.7. jhrg 2/24/15
    // using unique_ptr because auto_ptr deprecated. sbl 1.2.20
    unique_ptr<Array> response(new Array(bbox_name, proto));
 
    response->append_dim(num_dim, bbox_name);
 
    return response;
}
 
} //namespace functions