#! /bin/ash
#Set your hostname after this variable
readonly PATH=/usr/lib/restricted/bin
readonly fqdn=gopher.zcrayfish.soy
oldfqdn=zcrayfish.dyndns.org

error301 () {
   printf '%s\15\12' "HTTP/1.0 301 Moved Permanently" \
       "Location: https://$fqdn$REQUEST_URI" \
       "Content-Type: text/plain" \
       "Server: gopher to http gateway at $fqdn" \
       "" \
       "HTTP/1.0 301 Moved permanently" \
       "http://$oldfqdn$REQUEST_URI" \
       "Might be found at:" \
       "https://$fqdn$REQUEST_URI" \
       "" \
       "gopher to http gateway at $fqdn"
}

# Gather request and sanitise, not sure if needed now that we're running under lighttpd
filename="$(printf "%s" "$REQUEST_URI" | sed -e 's/%2c/,/gI' -e 's/%20/ /g')"

#old FQDN? Redirect them!
zdo=$(echo "$HTTP_HOST" | grep -i zcrayfish.dyndns.org)
test ! -z "$zdo" && error301 && exit

   #Step4
   case "$filename" in
       /7*httpsearch*)
           printf '%s\15\12' 'HTTP/1.0 200 OK' \
               'Content-Type: text/html' \
               "Server: gopher to http gateway at $fqdn" \
               '' \
               '<!DOCTYPE HTML PUBLIC "ISO/IEC 15445:2000//DTD HyperText Markup Language//EN">'
           searchytwothousand="$(printf $filename | sed 's/httpsearch=//g')"
           lynx -anonymous -dump -source "gopher://$fqdn:70$searchytwothousand" | \
               tidyp -in -w 0 -cn --doctype omit --show-errors 0 --show-warnings 0 --quiet 1 --uppercase-tags 1 --uppercase-attributes 1 --char-encoding utf8 | \
               sed -e 's/<A HREF="\/\//<A HREF="gopher:\/\//g' -e 's/<A HREF="gopher:\/\/'$fqdn':70/<A HREF="\/\/'$fqdn'/g' -e '/<HEAD>/a <LINK REL="STYLESHEET" HREF="//gopher.zcrayfish.soy/stylesheet.css">\n<LINK REL="SHORTCUT ICON" HREF="//gopher.zcrayfish.soy/favicon.ico">'
                   ;;

       /7*)
           printf '%s\15\12' "HTTP/1.0 200 OK" \
               "Content-Type: text/html" \
               "Server: gopher to http gateway at $fqdn" \
               "" \
               '<!DOCTYPE HTML PUBLIC "ISO/IEC 15445:2000//DTD HyperText Markup Language//EN">' \
               '<HTML><HEAD><TITLE></TITLE><LINK REL="STYLESHEET" HREF="//gopher.zcrayfish.soy/stylesheet.css">' \
               '<LINK REL="SHORTCUT ICON" HREF="//gopher.zcrayfish.soy/favicon.ico"></HEAD><BODY>' \
               '<P>This is a searchable gopher index. Enter search keywords below<BR>' \
               "<FORM ACTION='$filename' METHOD='GET'><P><TEXTAREA ROWS='10' COLS='72' NAME='httpsearch'></TEXTAREA><BR><INPUT TYPE='submit'></P></FORM>" \
               '</BODY></HTML>'

#               "<FORM ACTION='$fqdn$filename' METHOD='GET'>" \
#               '<P>This is a searchable gopher index. Enter search keywords below<BR><INPUT TYPE="TEXT" NAME="httpsearch"></P></FORM>' \

           ;;
#       /debug*)
#           printf '%s\15\12' "HTTP/1.0 200 OK" \
#               "Content-Type: text/plain" \
#               ""
#           set
#           ;;
       ###START OF DUMB / NON-INTELLIGENT GOPHER TYPES###
       /[04569IMPdghps]*)
           case "$filename" in
               /0*)
                   mimetype="Content-Type: text/plain"
                   ;;
               /4*)
                   mimetype="Content-Type: application/mac-binhex40"
                   ;;
               /5*)
                   mimetype="Content-Type: application/octet-stream"
                   ;;
               /6*)
                   mimetype="Content-Type: message/rfc822"
                   ;;
               /9*)
                   mimetype="Content-Type: application/octet-stream"
                   ;;
               /I*.webp)
                   mimetype="Content-Type: image/webp"
                   ;;
               /I*)
                   mimetype="Content-Type: image/jpeg"
                   ;;
               /M*)
                   mimetype="Content-Type: message/rfc822"
                   ;;
               /P*)
                   mimetype="Content-Type: application/pdf"
                   ;;
               /d*)
                   mimetype="Content-Type: application/octet-stream"
                   ;;
               /g*)
                   mimetype="Content-Type: image/gif"
                   ;;
               /h*)
                   mimetype="Content-Type: text/html"
                   ;;
               /p*)
                   mimetype="Content-Type: image/png"
                   ;;
               /s*)
                   mimetype="Content-Type: application/octet-stream"
                   ;;
           esac
           xyzzy="$(curl -q --disable -s --output - "gopher://$fqdn:70$filename" | base64)"
           isdumb="true"
           ;;
       ###END OF DUMB / NON-INTELLIGENT GOPHER TYPES###
       *)
               #Store lynx output for future processing
               xyzzy="$(lynx -anonymous -dump -source "gopher://$fqdn:70$filename" | \
               tidyp -in -w 0 --doctype omit --show-errors 0 --show-warnings 0 --quiet 1 --uppercase-tags 1 --uppercase-attributes 1 --char-encoding utf8 | \
               sed -e 's/<A HREF="\/\//<A HREF="gopher:\/\//g' -e 's/<A HREF="gopher:\/\/'$fqdn':70/<A HREF="/g' -f /srv/www/htdocs/head.sed -f /srv/www/htdocs/images.sed )"
               if [ "$mimetype" = "" ]; then
                       mimetype="Content-Type: text/html"
               fi
                   ;;
   esac

###OUTPUT SECTION###

#We'll use the output of Lynx or curl to determine if gopher content is 404d
#Non gophermap content may be binary, base64 it so the shell can deal with it
if [ "$isdumb" = "true" ] ; then
 precontent=$(echo "$xyzzy" | base64 -d)
else
 #precontent=$(echo "$xyzzy" | sed -n 's/.*<PRE>\(.*\)<\/PRE>.*/\1/p')
 precontent=$(echo "$xyzzy" | xargs -s 633 | grep -E -o "<PRE>.*?</PRE>")
fi

#See if there's an error
is403=$(echo "$precontent" | head -n1 | grep "Error: Access denied!")
is404=$(echo "$precontent" | head -n1 | grep "Error: File or directory not found!")

#Respond to any errors
if [ -n "$is403" ] ; then
 printf '%s\15\12' 'HTTP/1.0 403 Forbidden' && iserror="true"
fi

if [ -n "$is404" ] ; then
 printf '%s\15\12' 'HTTP/1.0 404 Not Found' && iserror="true"
fi

if [ -n "$iserror" ] ; then
       if [ "$isdumb" = "true" ] ; then
         printf '%s\15\12' "Content-Type: text/plain" \
         '%s\15\12' "Server: gopher to http gateway at $fqdn" \
         '' \
         "$precontent"
       else
         printf '%s\15\12' "Content-Type: text/html" \
         '%s\15\12' "Server: gopher to http gateway at $fqdn" \
         '' \
         '<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">' \
         "$xyzzy"
       fi
 exit
fi

#If no errors, then we go here
printf '%s\15\12' 'HTTP/1.0 200 OK' \
"$mimetype" \
"Server: gopher to http gateway at $fqdn" \
''
if [ "$mimetype" = "Content-Type: text/html" ]; then
       echo '<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">'
fi
if [ "$isdumb" = "true" ] ; then
 echo "$xyzzy" | base64 -d
else
 echo "$xyzzy"
fi
echo ""