#!/usr/bin/env /proj/axaf/bin/perlwrap

use warnings;

# The above will probably need to be changed to reflect your local
# perl installation.  /usr/bin/perl is a good possibility.

###############################################################################
#
# This program is a bare-bones example of how to automate the usage of
# the 'fix_offset' thread.  It expects as input the same lines which you
# would cut-and-paste into the text window of the Web thread tool.  
#
# All this program does is emulate the thread tool Web page and post the
# appropriate form data to the CGI script.  That CGI script retrieves aspect 
# files from the Chandra archive and the CXCDS CALDB, which is the reason it 
# cannot be run completely local to the users machine.
#
# Typical usage:
#   dmlist aspcorr_evt2.fits header,raw,clean | egrep 'TCTYP|TCRVL|ASCDSVER|DATE|OBS_ID' | fix_batch
#
# The program could easily be modified to take as input an event file name
# and do everything from there. 
#
# Copyright 2002   Tom Aldcroft
#
###############################################################################

##########################################################################
# INSTALLATION NOTES (Courtesy S. Gallagher)
# 
# Modules required
# (can be downloaded from http://www.cpan.org/modules/01modules.index.html)
# 
# HTML-Tree-3.13.tar.gz
#            (requires HTML-Tagset-3.03.tar.gz and HTML-Parser-3.26.tar.gz)
# HTML-Format-1.23.tar.gz
#            (requires Font-AFM-1.18.tar.gz)
# libwww-perl-5.65.tar.gz
#            (requires URI-1.22.tar.gz)
# 
# Module installation instructions are available at
#   http://www.cpan.org/modules/INSTALL.html
# or by typing
#   perldoc permodinstall
# at the command line.
#
##########################################################################

# Load Perl libraries (available from CPAN) which make it easy to
# do an HTTP request and parse the results
use HTML::TreeBuilder; 
use HTML::FormatText;
use HTTP::Request::Common qw(POST);
use LWP::UserAgent;

# Get the lines containing event file header keywords from STDIN
@input = <STDIN>;
$header_input = join '', @input;

# Generate a new Web user agent
$ua = LWP::UserAgent->new;

# Generate an HTTP request as if posting form data
$req = POST 'http://cxc.harvard.edu/cal/ASPECT/fix_offset/fix_offset.cgi',
    [ header => $header_input, "Click here" => 1];

# .. and post the form data
$response_html = $ua->request($req)->as_string;

# Now parse the returned HTML and print it
$html = HTML::TreeBuilder->new();
$formatter = HTML::FormatText->new(leftmargin=>0, rightmargin=>80);
$response = $formatter->format( $html->parse($response_html) );

print $response, "\n";

# A possible enhancement is to have the code automatically do the header
# updates, though it may be safer to explicitly view the results and
# cut-n-paste for each one.
#
# foreach ( grep /dmhedit/, split("\n",$response) ) {
#     print "$_\n";
#     system $_;
# }