#!/bin/sh
# cacophony by C. Duckworth --- hereby released to the public domain

SCRIPTDIR=/home/acdw/www

crlf() { # crlf < INPUT
	## Convert LF to CRLF
	sed 's/$/
/g'
}

log() { # log MESSAGE ...
	printf >&2 '%s\n' "$*"
}

http_header() { # http_header [STATUS] [MIMETYPE] [CHARSET]
	cat <<HEADER | crlf
HTTP/1.1 ${1:-200}
Content-Type: ${2:-text/html};charset=${3:-utf-8}

HEADER
}

html_footer() { # html_footer
	cat <<FOOTER
<footer>this page is a <a href="/src/${1##*/}">program</a>
served by <a href="https://git.acdw.net/cacophony">cacophony</a>.
</footer></body></html>
FOOTER
}

hcat() { # hcat [STATUS] < INPUT
	case "$(file -)" in
		*HTML*) http_header "{1:-200}" ;;
		*) http_header "${1:-200}" text/plain ;; # todo: smarter
	esac
	cat
}

hexec() { # hexec PROGRAM [http_header args]
	prog="$1"
	shift
	http_header "$@"
	"$prog"
	html_footer "$prog"
}

run() { # run
	pag="$PWD$PATH_INFO"
	src="$SCRIPTDIR$PATH_INFO"

	if test / = "$PATH_INFO"
	then PATH_INFO=/index run

	elif ! test -d "$pag" && test -x "$src"
	then hexec "$src" 200

	elif ! test -d "$pag" && test -r "$pag"
	then hcat 200 < "$pag"

	elif test -d "$pag" && test -r "$pag/index.html"
	then hcat 200 < "$pag/index.html"

	else 
		case "$PATH_INFO" in
			/src/*) hcat 200 < "$SCRIPTDIR/${PATH_INFO#/src/}" ;;
			*) http_header 404 ;;
		esac
	fi
}

run