<?php
  function mk_contour ($this_map, $layer_name, $input_grd, $scratch_prefix) {
    // load the imagemap .map skeleton
    $this_layer = $this_map->getLayerByName($layer_name);

    // pick the correct metadata incrs based on the gmt grid filename
    if (strpos($input_grd,'_inches_mercury') !== false) {
      $contour_metadata_item    = 'contour_incr_inches_mercury';
      $annotation_metadata_item = 'annotation_incr_inches_mercury';
    }
    else {
      $contour_metadata_item    = 'contour_incr';
      $annotation_metadata_item = 'annotation_incr';
    }
    $contour_incr    = $this_layer->getMetadata($contour_metadata_item);
    $annotation_incr = $this_layer->getMetadata($annotation_metadata_item);

    // get the extents
    $grd_format_bounds = $this_map->extent->minx
      .'/'.$this_map->extent->maxx
      .'/'.$this_map->extent->miny
      .'/'.$this_map->extent->maxy;

    // set the WIDTH & HEIGHT of the new .map
    $this_width = $this_map->width;
    $this_height = $this_map->height;

    $command_filename = '/tmp/ms_tmp/'
      .$scratch_prefix.'_'
      .$layer_name
      .'_GMT.bash';

    $dest_ps = '/tmp/ms_tmp/'
      .$scratch_prefix.'_'
      .$layer_name.'.ps';
    $dest_png = '/tmp/ms_tmp/'
      .$scratch_prefix.'_'
      .$layer_name.'.png';
    $dest_wld = '/tmp/ms_tmp/'
      .$scratch_prefix.'_'
      .$layer_name.'.wld';

    $command_file = fopen($command_filename,"w");

    $grd_header = '#!/bin/bash'."\n"
      ."cd /tmp\n"
      ."rm -f .gmt*\n"
      ."/usr2/local/gmt/GMT3.4.3/bin/gmtset PAPER_MEDIA A0\n";

    fwrite($command_file,$grd_header);

    // add color if this is ssh
    if (strpos($input_grd,'sea_surface_height') !== false) {
      $color_table     = $this_layer->getMetadata('color_table');
      $contour_limits  = $this_layer->getMetadata('contour_limits');
      $grdimage_str = '/usr2/local/gmt/GMT3.4.3/bin/grdimage'
        ." $input_grd"
        ." -R$grd_format_bounds"
        .' -JX'.($this_width/72.0).'i'
        .'/'.($this_height/72.0).'i'
        ." -C$color_table"
        .' -P -X0 -Y0 -S3 -T -K > '.$dest_ps."\n";
      fwrite($command_file, $grdimage_str);
      $grdcontour_str = '/usr2/local/gmt/GMT3.4.3/bin/grdcontour'
        ." $input_grd"
        ." -R$grd_format_bounds"
        .' -JX'.($this_width/72.0).'i'
        .'/'.($this_height/72.0).'i'
        ." -C$contour_incr -A$annotation_incr -L$contour_limits"
        .' -G3i/10 -P -X0 -Y0 -S3 -O >> '.$dest_ps."\n";
      fwrite($command_file, $grdcontour_str);
    }
    else if (strpos($layer_name,'etopo2_bathy_relief') !== false) {
      $input_grd   = $this_layer->getMetadata('gmt_grid');
      $color_table = $this_layer->getMetadata('color_table');
      $grdimage_str = '/usr2/local/gmt/GMT3.4.3/bin/grdimage'
        ." $input_grd"
        ." -R$grd_format_bounds"
        .' -JX'.($this_width/72.0).'i'
        .'/'.($this_height/72.0).'i'
        ." -C$color_table"
        .' -P -X0 -Y0 -K > '.$dest_ps."\n";
      fwrite($command_file, $grdimage_str);
    }
    else if (strpos($layer_name,'etopo2_bathy_contour_only') !== false) {
      $input_grd   = $this_layer->getMetadata('gmt_grid');
      $contour_limits  = $this_layer->getMetadata('contour_limits');
      $contour_incr_table  = $this_layer->getMetadata('contour_incr_table');
      $grdcontour_str = '/usr2/local/gmt/GMT3.4.3/bin/grdcontour'
        ." $input_grd"
        ." -R$grd_format_bounds"
        .' -JX'.($this_width/72.0).'i'
        .'/'.($this_height/72.0).'i'
        ." -C$contour_incr_table"
        ." -As -L$contour_limits"
        .' -Wc2/150/150/150'
        .' -Wa2/150/150/150'
        .' -G'.($this_width/72.0*0.95).'i/10 -P -X0 -Y0 >> '.$dest_ps."\n";
      fwrite($command_file, $grdcontour_str);
    }
    else {
      $grdcontour_str = '/usr2/local/gmt/GMT3.4.3/bin/grdcontour'
        ." $input_grd"
        ." -R$grd_format_bounds"
        .' -JX'.($this_width/72.0).'i'
        .'/'.($this_height/72.0).'i'
        ." -C$contour_incr -A$annotation_incr"
        .' -G3i/10 -P -X0 -Y0 > '.$dest_ps."\n";
      fwrite($command_file, $grdcontour_str);
    }

    $imagemagick_cmd = '/usr/local/bin/convert'
      ." $dest_ps"
      .' -size 2380x3368'
      .' -crop '.$this_width.'x'.$this_height
      .'+0+'.(3368-$this_height)
      .' -transparent "rgb(255,255,255)" -type TrueColor'
      .' '.$dest_png."\n";

    fwrite($command_file, $imagemagick_cmd);

    fclose($command_file);

    putenv("PATH=/usr2/local/gmt/GMT3.4.3/bin:/usr/local/bin:/bin:/usr/bin:/usr/X11R6/bin:/usr/local/pgsql/bin:/usr2/installation_files/mapserver-4.1");
    putenv("GMTHOME=/usr2/local/gmt/GMT3.4.3");
`echo "$command_filename" >> /tmp/maplog`;
    $res = shell_exec('/bin/bash '.$command_filename." 2>&1");

    $x_incr = abs($this_map->extent->maxx - $this_map->extent->minx);
    $y_incr = abs($this_map->extent->maxy - $this_map->extent->miny);

    $wld_file = fopen($dest_wld,"w");

    $wld_contents = ($x_incr / $this_width)."\n"
      ."0\n0\n"
      .(-$y_incr / $this_height)."\n"
      .$this_map->extent->minx."\n"
      .($this_map->extent->miny + $y_incr)."\n";

    fwrite($wld_file, $wld_contents);

    fclose($wld_file);

    return $dest_png;
  }
?>