#!/bin/bash
# arcview.sh - Archive Viewer
# Author: Sean B. Palmer, inamidst.com
# Source: http://inamidst.com/code/arcview
# License: MIT License; share and enjoy!

function doc() { 
   echo 'This is a CGI script for viewing archives'
   echo 'Try using the following in an .htaccess: '
   echo 'RewriteRule \.tar\.(gz|bz2)/$ arcview.cgi [L]'
}

# The following variables are configurable
# But the script will work with the defaults

STYLE=/trove/arcview.css
NOTFOUND=/bin/404.cgi

# The rest is not so configurable

case $REQUEST_URI in
   *.tar.gz/) TYPE=z; SUFFIX=.tar.gz;; 
   *.tar.bz2/) TYPE=j; SUFFIX=.tar.bz2;; 
   *) notfound;;
esac

AFN=${REQUEST_URI%%$SUFFIX/*}$SUFFIX
TZIP=${AFN%/}
AFN=$DOCUMENT_ROOT${AFN#/}
ANAME=$(basename $AFN $SUFFIX)
FN=${REQUEST_URI#*$SUFFIX/}
FN=${FN%/}

if [ "$REQUEST_METHOD" = 'POST' ]
then GETVALUE='import cgi; print cgi.FieldStorage()["filename"].value'
     FILEPATH=$(python -c "$GETVALUE")
fi

function serve() { 
   echo Content-Type: ${1:-text/html}
   echo 
   cat
}

function mimetype() { 
   case $1 in
      html) echo text/html;;
      jpg) echo image/jpeg;; 
      gif) echo image/gif;; 
      png) echo image/png;; 
      *) echo text/plain;; 
   esac
}

function directory() { 
   echo "<title>$ANAME</title>"
   echo "<base href='http://$SERVER_NAME$TZIP/'>"
   if [ -f "$DOCUMENT_ROOT$STYLE" ]
   then echo "<link rel='stylesheet' type='text/css' href='$STYLE'>"
   fi

   echo "<h1>$ANAME</h1>"
   echo "<p>Download archive: <a href='$TZIP'>$ANAME$SUFFIX</a>"

   echo '<ul>' # @@ escape &, etc.
   while true
   do read FILENAME || break
      FILENAME=$(echo "$FILENAME" | sed 's!^[^/]*/!!')
      [ ! -z "$FILENAME" ] || continue

      echo '<li><form action="" method="post">'
      echo "<div><input type='hidden' name='filename' value='$FILENAME'>"
      echo "<input type='submit' value='$FILENAME'>"
      echo '</div></form></li>'
   done
   echo '</ul>'

   ARCVIEW='http://inamidst.com/code/arcview'
   echo "<p>(Powered by <a href='$ARCVIEW'>arcview</a>.)"
}

# Main Program

if [ -z "$SCRIPT_NAME" ]
then doc && exit

# @@ Warn about badly designed archives?
elif [ "$REQUEST_METHOD" = 'POST' ] && \
     tar -${TYPE}tf $AFN $ANAME/$FILEPATH &> /dev/null
then tar -O${TYPE}xvf $AFN $ANAME/$FILEPATH | \
     serve $(mimetype ${FILEPATH##*.})

elif [ -z "$FN" ]
then tar -${TYPE}tf $AFN | directory | serve

elif [ -x "$DOCUMENT_ROOT$NOTFOUND" ]
then $DOCUMENT_ROOT$NOTFOUND

else echo Status: 404
     echo Content-Type: text/plain
     echo 
     echo Not Found
fi

# [EOF]