#!/bin/sh
#
# A Hypertext Archie Gateway for the CGI interface of an httpd deamon
#
# Version 1.2 	21 Jan 94
#
# This script relies on the C-archie client from Brendan Kehoe
# Once installed, please set the correct path below.
# You can obtain the latest version from a comp.sources archive, or at
# file://ftp.uu.net/networking/info-service/archie/clients
#
# QUERIES 
#
# An accompanying HTML Form sets up the query and allows all the functionality
# of c-archie to be set explicitly. 
# 
# For clients without form support the script can be called without arguments,
# resulting in an ISINDEX page. Reasonable defaults are taken
# for each option. A pointer to the script without arguments is included in
# the form header.
#
# The accompanying Form relies heavilly on Martijn Koster's ArchiePlex Form.
# Infact it will probably work with that too.
#
# HYPERTEXT RESULTS
#
# The main point of providing this script is infact to format the Archie
# results into Hypertext. This is acheived with a bit of awk script.
# Hypertext links point to the files and directories listed by archie. 
# One click and you've got what was asked for !
# Mosaic's internal icons are used for file and directory pointers, a
# textual alternative is provided for browsers without. 
#
# INSTALLATION (very easy !)
#
# 1. Install C-archie (see above for suggested sources)
# 2. Edit the line in AA describing the location of C archie
# 3. Put AA in your servers cgi-bin. 
# 4. Put AA.html in your htdocs tree, and away you go...
#
# You might like to edit some of the defaults in AA, such as the server for
# non-forms based queries. See DEFAULT_SERVER and others below.
#
# PORTING NOTES
#
# This script should work on almost all systems with a bourne shell, awk and
# c-archie. Try the gnu utilities gawk and bash on non-unix machines 
# (NB I've not tried this). 
#
# I've used it sucessfully on Sillicon Graphics machines running IRIX 4 but..
#
#Ultrix
#
# set the first line to be #!/bin/sh5 otherwise the [ dosn't function correctly.
#
#
# Acknowledgements
#
# Thanks to Martijn Koster for his ArchiePlex interface. It was the
# inspiration for me to provide one for NCSA's httpd. I used his HTML form
# as the bsis for this script.
# Thanks also to Brendan Kehoe for his archie client, that was 
# quite straightforward to HyperTextualise (a new word ?)
#
# Thanks for the comments from the following people that brought version 1.1
# JQ Johnson, Simon Poole, Paul Harrington.
#
# Enjoy !
#
# Guy Brooker
# guy@jw.estec.esa.nl
#
# 21/01/94
#
# Modifications
# 
# Version 1.0
# 19/12/93	Guy Brooker
# 
# Version 1.1
# 07/01/94	Guy Brooker
#		o Dangerous Security Hole Removed. For a non-forms based query
#		  QUERY_STRING was assigned query=$*. This enabled malicious
#		  queries such as `cat</etc/passwd`. The QUERY_STRING passed
#		  by httpd is now used, as this escapes these 'special
#		  characters' i.e `ls` = %60ls%60. A hail of thanks go to
#		  JQ Johnson for pointing out the problem.
#
#		o The Swiss entry was removed due to site access resrictions.
#
#		o Horizontal rules are used to separate each Host.
#
# Version 1.2
# 21/01/94	Guy Brooker
#		o Improved variable expansion to check legality of identifiers
#		  and remove the possiblility of the shell interpreting any
#		  characters passed in QUERY_STRING.
#
#		o Report the name of the Archie server used
#
#		o Nice Level now works correctly
#
#		o Added DEFAULT_ variables
#
#

# **** **** **** ****    CONFIGURABLE VARIABLES     **** **** **** ****

WEATHER=/usr/local/bin/weather

# **** **** **** **** NO CONFIGURATION NEEDED BELOW **** **** **** ****

#
#.. Ensure that 'archie' is available on this machine
#
if [ -x $WEATHER ]; then

#
#..	To support an ISINDEX type search, set query string if given
#	an argument on the command line
#
    if [ $# -gt 0 ]; then 
	PREFIX="query="
    fi
#
#..	Check that a query has been made
#
    if [ $QUERY_STRING ]; then

#
#..		Strip the variables out from the query string,
#		and assign them into the environment, prefixed by 'QS_'
#
#		 o sed removes any ' that would upset quoted assignment
#
#		 o awk ensures that 
#			- all variables passed have legal names
#			- special characters are not interpreted by sh
#
	eval `echo $PREFIX$QUERY_STRING | sed -e 's/'"'"'/%27/g' | \
	      awk 'BEGIN{RS="&";FS="="}
		$1~/^[a-zA-Z][a-zA-Z0-9_]*$/ {
			printf "QS_%s=%c%s%c\n",$1,39,$2,39}' `
#
#..		Set the search type
#
	case $QS_time in
		Latest)					OPT_time='' ;;
		Today)					OPT_time='t' ;;
		Yesterday)				OPT_time='y' ;;
		*)					OPT_time='' ;;
	esac
#
#..		Set the server address
#
	case $QS_decode in
		1)			OPT_prog='flatsa' ;;
		2)			OPT_prog='flatsadecode' ;;
		3)			OPT_prog='flatsafulldecode' ;;
		*)			OPT_prog='flatsafulldecode' ;;
	esac
#
#..		Output header
#
	cat << EOM
Content-type: text/html

<HEAD>
<TITLE>Observation Results for $QS_station </TITLE>
</HEAD>
<BODY>
<H1>Observations at $QS_station for $QS_time</H1>
<HR>
EOM
	echo '<pre>'
	$WEATHER -c $OPT_prog $QS_station $OPT_time | ./clean
	echo '</pre>'

	echo '</BODY>'

	else

#
#..		The script was called without a query. 
#		Provide an ISINDEX type response for browsers
#		without form support.
#
	cat << EOM
Content-type: text/html

<HEAD>
<TITLE>Current Observation Search</TITLE>
</HEAD>
<BODY>
<H1>Current Observation Search</H1>

<P>
<HR>
<FORM ACTION="/cgi-bin/obs">
Enter Station Name <INPUT TYPE="text" SIZE="9" MAXLENGTH="9" NAME="station"><P>
A station name is a three letter identifier for an airport or a weather
station. One example is "roc" for Rochester, New York. If you want a state
wide search, enter "@NY", where the NY is a two letter ID of a state (NY is New
York).</p>
Enter Time Option
<SELECT NAME="time">
<option>Latest
<option>Today
<option>Yesterday
</select><p>
<h3>Decoding of Data?</h3><p>
<input type="radio" NAME="decode" Value="1"> Raw
<input type="radio" NAME="decode" Value="2"> Partial
<input type="radio" NAME="decode" Value="3"> Full<p>
<p>A raw decode gives the observations in SA format. If you are not familiar with
this format (most pilots and meteorologists are) then use a partial or full
decode option to turn the observations into readable english text</p>

<INPUT TYPE="submit">Press Here when Finished<p>
</BODY>
EOM
    fi
else
#
# Brendan Kehoe's Archie Client was not found
# Report a useful message
#
	cat << EOM
Content-type: text/html

<HEAD>
<TITLE>WX Program not found</TITLE>
</HEAD>
<BODY>
<H1>WX Program not found</h1>
<ADDRESS>don@weather.brockport.edu</ADDRESS>
</BODY>
EOM

fi