#!/bin/bash

file=$(sed -e's/%\([0-9A-F][0-9A-F]\)/\\\\\x\1/g' <<< "$QUERY_STRING" | xargs echo -e )
file=${file##*/}
file=${file%%;*}

if [ -e "$file" ]; then
    sum=$(md5sum "$file" | sed -e 's/^\([0-9a-fA-F]*\)\s.*$/\1/')
    sum="/tmp/thumbs/$sum"

    mkdir -p /tmp/thumbs
    if ! [ -e "$sum" ]; then
        convert "$file" -auto-orient -thumbnail 250x90 -unsharp 0x.5 "gif:$sum"
    fi

    export TZ=UTC0
    t=$(stat --printf="%Y" "$sum")
    mod=$(awk "BEGIN{print strftime(\"%a, %d %b %Y %H:%M:%S %Z\", $t)}")

    cat <<-EOF
        Content-Type: image/gif
        Last-Modified: $mod

    EOF

    cat "$sum"
else
    cat <<-EOF
        Status: 400 Bad Image Request

    EOF
fi