#
#	this assumes the time span on input docs will be 27 days or less
#	this assumes that the current year is less than 2100
#	this asssumes that no single closure will cover more than 24 hours
#       this assumes that the date validity range between two input files always match
#

use strict;
use warnings;

use Time::Local;

sub fmon {
	if ($_[0] =~ /^\d{6}\wJAN\d{2}$/i) {return "00";}
	if ($_[0] =~ /^\d{6}\wFEB\d{2}$/i) {return "01";}
	if ($_[0] =~ /^\d{6}\wMAR\d{2}$/i) {return "02";}
	if ($_[0] =~ /^\d{6}\wAPR\d{2}$/i) {return "03";}
	if ($_[0] =~ /^\d{6}\wMAY\d{2}$/i) {return "04";}
	if ($_[0] =~ /^\d{6}\wJUN\d{2}$/i) {return "05";}
	if ($_[0] =~ /^\d{6}\wJUL\d{2}$/i) {return "06";}
	if ($_[0] =~ /^\d{6}\wAUG\d{2}$/i) {return "07";}
	if ($_[0] =~ /^\d{6}\wSEP\d{2}$/i) {return "08";}
	if ($_[0] =~ /^\d{6}\wOCT\d{2}$/i) {return "09";}
	if ($_[0] =~ /^\d{6}\wNOV\d{2}$/i) {return "10";}
	if ($_[0] =~ /^\d{6}\wDEC\d{2}$/i) {return "11";}
}

sub m2d {
	my @t = localtime($_[0]*60);
	return sprintf "%02d%02d%02d", $t[3], $t[2], $t[1];
}

my ($d,$t);
foreach (<*>) {
	$d = $_ if (/\.dat$/i);
	$t = $_ if (/\.mrg$/i);
}
my (@dl,@tl);
if (open(D, $d)) {@dl = <D>; close(D); print "Found $d\n";} else {print "Error: missing XXX.\n";}
if (open(T, $t)) {@tl = <T>; close(T); print "Found $t\n";} else {print "Error: missing YYY.\n";}
       
my (@big,@n,@m);
for (@dl,@tl) {
	chomp($_);
	if (/\w{4}\d{2}\/\d{6}\w{4}\d{2}\/\/$/) {@n = split(/\//);}
	if (/^\/\d{6}\/\d{6}\//) {
		@m = split(/\//);
		my ($t1,$t2);
		if (substr($m[1],0,2) < substr($n[3],0,2)) {
			if (fmon($n[3]) eq 11) {
				$t1 = timelocal(0,substr($m[1],4,2),substr($m[1],2,2),substr($m[1],0,2),fmon($n[4]),"20".substr($n[4],10,2))/60;
			} else {
				$t1 = timelocal(0,substr($m[1],4,2),substr($m[1],2,2),substr($m[1],0,2),fmon($n[4]),"20".substr($n[3],10,2))/60;
			}
		} else {
			$t1 = timelocal(0,substr($m[1],4,2),substr($m[1],2,2),substr($m[1],0,2),fmon($n[3]),"20".substr($n[3],10,2))/60;
		}
		if (substr($m[2],0,2) < substr($n[3],0,2)) {
			if (fmon($n[3]) eq 11) {
				$t2 = timelocal(0,substr($m[2],4,2),substr($m[2],2,2),substr($m[2],0,2),fmon($n[4]),"20".substr($n[4],10,2))/60;
			} else {
				$t2 = timelocal(0,substr($m[2],4,2),substr($m[2],2,2),substr($m[2],0,2),fmon($n[4]),"20".substr($n[3],10,2))/60;
			}
		} else {
			$t2 = timelocal(0,substr($m[2],4,2),substr($m[2],2,2),substr($m[2],0,2),fmon($n[3]),"20".substr($n[3],10,2))/60;
		}
		push @big,[$t1,$t2,$m[5]];
	}
}

my %values = ();
for my $e (0 .. $#big) {
	my $l = $big[$e];
	for my $min ($l->[0] .. $l->[1]) {
		if ((!exists $values{$min}) or ($values{$min} > $l->[2])) {
			$values{$min} = $l->[2];
		}
	}
}

print "...processing...\n";

my @res1;
my $s = timelocal(0,substr($n[3],4,0),substr($n[3],2,0),substr($n[3],0,2),fmon($n[3]),"20".substr($n[3],10,2))/60;
my $e = timelocal(0,substr($n[4],4,0),substr($n[4],2,0),substr($n[4],0,2),fmon($n[4]),"20".substr($n[4],10,2))/60;
while ($s < $e) {
	++$s until exists $values{$s} or $s == $e;
	my ($val,$start,$end);
	if ($s != $e) {
		$val = $values{$s};
		$start = $s;
		++$s while exists $values{$s} and $values{$s} == $val;
		$end = $s - 1;
		push @res1,[m2d($start),m2d($end),$val];
	}
}

my @res2;
foreach (@res1) {
	if (substr(@$_[0],0,2) == substr(@$_[1],0,2) ) {
		push @res2,[@$_[0],@$_[1],@$_[2]];
	} else {
		push @res2,[@$_[0],substr(@$_[0],0,2)."2359",@$_[2]];
		push @res2,[substr(@$_[1],0,2)."0000",@$_[1],@$_[2]];
	}
}

open (C,'>CDA.txt');
my @last = ("","","");
print C "To do later: ... a lot of specific formatting work(easy)\n";
foreach (@res2) {
	if (substr($last[0],0,2) ne substr(@$_[0],0,2)) { print C "\n"; }
	print C @$_[0]," ",@$_[1]," ",@$_[2],"\n";
	$last[0] = @$_[0];
}
close(C);
print "Complete.\n";

print "\nPress Enter to exit.\n";
my $end = <STDIN>;