#!/usr/bin/perl
# -*- perl -*-
# Written by Derrick J Brashear, KB3EGH
# Released to the public domain.

# Usage: mapfgd <directory>
# Creates fake fgd files for all correctly USGS-named maps which don't 
# already have them

local (@dirlist) = @ARGV;
local ($mapdir);
foreach $mapdir (@dirlist)
{
    opendir (DIR, $mapdir) || die "mapini: couldn't open directory \`$mapdir': $!\n";
    local ($file, $fullfile, $expr, $mlat, $mlon, $mlats, $mlons);
    local ($nlat, $nlon, $nlats, $nlons);
    local ($dlat, $dlon, $inifile);
    local ($imgwidth, $imglength, $imgres, $imgdepth, $imgphotometric);
    local ($imgtimestamp);
    foreach $file (sort grep (! /^\./, readdir (DIR)))
    {
        # Only examine .tif files.
        next unless $file =~ /\.tif$/;
        next unless $file =~ /^[iIoOcCfFkKlLpPjJgG]/;
        $fullfile = $mapdir . '/' . $file;
        $inifile = $mapdir . '/' . $file;
        $inifile =~ s/\.tif$/.fgd/;
        next if (-f $inifile);
        open (INI, ">$inifile");
        $file =~ /^([iIoOcCfFkKlLpPjJgG])([0-9][0-9])([0-9][0-9][0-9])([a-hA-H])([1-8])/;
        $letter = $1;
        $mlat = $2;
        $mlon = $3;
        $mlats = $4;
        $mlons = $5;

        if ($letter eq 'c') {
            $dlon = 0-$mlon-2;
            printf INI "1.5.1.1   WEST BOUNDING COORDINATE:  %.6f\n", $dlon;
            $dlon = 0-$mlon;
            printf INI "1.5.1.2   EAST BOUNDING COORDINATE:  %.6f\n", $dlon;
            $dlat = $mlat+1;
            printf INI "1.5.1.3   NORTH BOUNDING COORDINATE:  %.6f\n", $dlat;
            $dlat = $mlat;
            printf INI "1.5.1.4   SOUTH BOUNDING COORDINATE:  %.6f\n", $dlat;
        } else {
            if (($letter eq 'f') || ($letter eq 'g')){
                $dlon = 0-$mlon-1;
                printf INI "1.5.1.1   WEST BOUNDING COORDINATE:  %.6f\n", $dlon;
                $dlon = 0-$mlon-(.125*$mlons)+.125;
                printf INI "1.5.1.2   EAST BOUNDING COORDINATE:  %.6f\n", $dlon;
                $dlat = $mlat+.375+(.125*(&lettonum ($mlats)));
                printf INI "1.5.1.3   NORTH BOUNDING COORDINATE:  %.6f\n", $dlat;
                $dlat = $mlat-.125+(.125*(&lettonum ($mlats)));
                printf INI "1.5.1.4   SOUTH BOUNDING COORDINATE:  %.6f\n", $dlat;
            } else {
                if ($letter eq 'k') {
                    $dlon = 0-$mlon-(.125*$mlons)-.125;
                    printf INI "1.5.1.1   WEST BOUNDING COORDINATE:  %.6f\n", $dlon;
                    $dlon = 0-$mlon-(.125*$mlons)+.125;
                    printf INI "1.5.1.2   EAST BOUNDING COORDINATE:  %.6f\n", $dlon;
                    $dlat = $mlat+(.125*(&lettonum ($mlats)));
                    printf INI "1.5.1.3   NORTH BOUNDING COORDINATE:  %.6f\n", $dlat;
                    $dlat = $mlat-.125+(.125*(&lettonum ($mlats)));
                    printf INI "1.5.1.4   SOUTH BOUNDING COORDINATE:  %.6f\n", $dlat;
                } else {
		    if ($letter eq 'i') {
			$dlon = 0-$mlon-(.125*$mlons)-.250;
			printf INI "1.5.1.1   WEST BOUNDING COORDINATE:  %.6f\n", $dlon;
			$dlon = 0-$mlon-(.125*$mlons)+.125;
			printf INI "1.5.1.2   EAST BOUNDING COORDINATE:  %.6f\n", $dlon;
			$dlat = $mlat+.125+(.125*(&lettonum ($mlats)));
			printf INI "1.5.1.3   NORTH BOUNDING COORDINATE:  %.6f\n", $dlat;
			$dlat = $mlat-.125+(.125*(&lettonum ($mlats)));
			printf INI "1.5.1.4   SOUTH BOUNDING COORDINATE:  %.6f\n", $dlat;
		    } else {
			$dlon = 0-$mlon-(.125*$mlons);
			printf INI "1.5.1.1   WEST BOUNDING COORDINATE:  %.6f\n", $dlon;
			$dlon = 0-$mlon-(.125*$mlons)+.125;
			printf INI "1.5.1.2   EAST BOUNDING COORDINATE:  %.6f\n", $dlon;
			$dlat = $mlat+(.125*(&lettonum ($mlats)));
			printf INI "1.5.1.3   NORTH BOUNDING COORDINATE:  %.6f\n", $dlat;
			$dlat = $mlat-.125+(.125*(&lettonum ($mlats)));
			printf INI "1.5.1.4   SOUTH BOUNDING COORDINATE:  %.6f\n", $dlat;
		    }
                }
            }
        }

        close (INI);
    }
    closedir (DIR);
}

sub lettonum
{
    local ($let) = @_;
    if ($let eq 'a')
    {return 1;}
    if ($let eq 'b')
    {return 2;}
    if ($let eq 'c')
    {return 3;}
    if ($let eq 'd')
    {return 4;}
    if ($let eq 'e')
    {return 5;}
    if ($let eq 'f')
    {return 6;}
    if ($let eq 'g')
    {return 7;}
    if ($let eq 'h')
    {return 8;}
}
sub nextlet
{
    local ($let,$scale) = @_;
    if ($scale eq 'c') 
    {$nlat++;return 'a';}
    if ($scale eq 'f') {
        if ($let eq 'a') 
        {return 'e';}
        if ($let eq 'e') 
        {$nlat++;return 'a';}
    }    
    if ($let eq 'a')
    {return 'b';}
    if ($let eq 'b')
    {return 'c';}
    if ($let eq 'c')
    {return 'd';}
    if ($let eq 'd')
    {return 'e';}
    if ($let eq 'e')
    {return 'f';}
    if ($let eq 'f')
    {return 'g';}
    if ($let eq 'g')
    {return 'h';}
    if ($let eq 'h')
    {$nlat++;return 'a';}
}
sub nextnum
{
    local ($let,$scale) = @_;
    if ($scale eq 'c') {
        $nlon+=2;
        if ($nlon < 100) {
            $nlon="0$nlon";
        }
        return '1';
    }
    if ($scale eq 'f') {
        $nlon++;
        if ($nlon < 100) {
            $nlon="0$nlon";
        }
        return '1';
    }
    if ($let eq '1')
    {return '2';}
    if ($let eq '2')
    {return '3';}
    if ($let eq '3')
    {return '4';}
    if ($let eq '4')
    {return '5';}
    if ($let eq '5')
    {return '6';}
    if ($let eq '6')
    {return '7';}
    if ($let eq '7')
    {return '8';}
    if ($let eq '8')
    {$nlon++;
     if ($nlon < 100) {
         $nlon="0$nlon";
     }
     return '1';}
}
sub oldlastnum
{
    local ($let,$scale) = @_;
    if ($let = 1) 
    {print INI "let was 1\n";$let=9; $nlon--; $nlon="0$nlon";}
    $let--;
    return $let;
}
sub lastnum
{
    local ($let,$scale) = @_;
    if ($scale eq 'c') {
        $nlon-=2; 
        if ($nlon < 100) {
            $nlon="0$nlon";
        }
        return '1';
    }
    if ($scale eq 'f') {
        $nlon--; 
        if ($nlon < 100) {
            $nlon="0$nlon";
        }
        return '1';
    }
    if ($let eq '1') {
        $nlon--; 
        if ($nlon < 100) {
            $nlon="0$nlon";
        }
        return '8';
    }
    if ($let eq '2')
    {return '1';}
    if ($let eq '3')
    {return '2';}
    if ($let eq '4')
    {return '3';}
    if ($let eq '5')
    {return '4';}
    if ($let eq '6')
    {return '5';}
    if ($let eq '7')
    {return '6';}
    if ($let eq '8')
    {return '7';}
}
sub lastlet
{
    local ($let,$scale) = @_;
    if ($scale eq 'c') 
    {$nlat--;return 'a';}
    if ($scale eq 'f') {
        if ($let eq 'a') 
        {$nlat--;return 'e';}
        if ($let eq 'e') 
        {return 'a';}
    }    
    if ($let eq 'a')
    {$nlat--;return 'h';}
    if ($let eq 'b')
    {return 'a';}
    if ($let eq 'c')
    {return 'b';}
    if ($let eq 'd')
    {return 'c';}
    if ($let eq 'e')
    {return 'd';}
    if ($let eq 'f')
    {return 'e';}
    if ($let eq 'g')
    {return 'f';}
    if ($let eq 'h')
    {return 'g';}
}