#!/bin/sh

volmap="vol.map"

unlinked_ignores='
# care only about subdirs
!($0 ~ "/")                 { next }

# sources
/\/src\//                   { next }
/Makefile$/                 { next }
/\/ID[.]desc$/              { next }
/\/ID[.]name$/              { next }
/[.]templ[.]html$/          { next }
/[.]dot$/                   { next }
/09_appendix\/action_src/   { next }

/06_feature\/djopt\/.*\.txt$/           { next }
/06_feature\/djopt\/Pre.html$/          { next }
/06_feature\/djopt\/Post.html$/         { next }
/06_feature\/scripting\/.*\/ex.html$/   { next }

# tmp/backup leftover
/[.]svg[.]png$/                { next }
/[.]out[.]png$/                { next }
/06_feature\/stroke\/.*\.png$/ { next }
/PCB\.[^\/.]*\.save$/          { next }
/PCB\.[^\/.]*\.backup$/        { next }
/[.]pyc$/                      { next }
'

build_list()
{
	local vol=0 img=0

	while test $# -gt 0
	do
		case "$1" in
			-v|--vol) vol=1;;
			-i|--img) img=1;;
			*) echo "unknown list parameter $1" >&2; exit 1;;
		esac
		shift 1
	done

echo "index.html" | awk -v "vol=$vol" -v "volmap=$volmap" -v "img=$img" '
	BEGIN {
		nopen=0
		dsq = "[\"'\'']"
		if (vol) {
			while((getline < volmap) == 1)
				if (NF == 2)
					VOL[$1] = $2
		}
	}

	function append(path, vp)
	{
		if (path == "")
			return 0
		if (path in SEEN)
			return 0
		SEEN[path]= 1
		if (vol) {
			vp = path
			sub("/.*", "", vp)
			print path "\t" int(VOL[vp])
		}
		else
			print path
		return 1
	}

	function mkpath(cwd, path,   P,v,n,m,found)
	{
		if (path ~ "://")
			return ""
		sub("#.*$", "", path)
		if (path == "")
			return ""

		path = cwd "/" path
		gsub("//*", "/", path)
		v = split(path, P, "/")
		for(n = 2; n < v; n++) {
			if (P[n] == "..") {
				found=0
				for(m = n-1; m >= 0; m--) {
					if (P[m] != "") {
						P[m] = ""
						P[n] = ""
						found=1
						break;
					}
				}
				# ponting to parent of root
				if (!found)
					return ""
			}
		}
		path=""
		for(n = 1; n < v; n++)
			if (P[n] != "")
				path = path P[n] "/"
		path = path P[v]

		m = "^" cwd
		if ((cwd != "") && !(path ~ m)) {
			# pointing to parent from the current search
			return ""
		}

		return path
	}

	function dump_links(cwd, fn   , ors, line, path, found)
	{
		ors = RS
		RS="[<]"
		while((getline < fn) == 1) {
			found = 0

			if ((($1 == "a") || ($1 == "A")) && ($0 ~ "href=")) {
				line=$0
				gsub("\n", " ", line)
				sub(".*href=" dsq, "", line)
				sub(dsq ".*", "", line)
				found=1
			}

			if (img && (tolower($1) == "img") && ($0 ~ "src=")) {
				line=$0
				gsub("\n", " ", line)
				sub(".*src=" dsq, "", line)
				sub(dsq ".*", "", line)
				found=1
			}

			if (found) {
				path = mkpath(cwd, line)
				if (append(path))
					process(path)
			}
		}
		RS=ors
	}

	function process(fn)
	{
		if (fn == "")
			return
		cwd=fn
		sub("[^/]*$", "", cwd)
		dump_links(cwd, fn)
	}

	{ process(mkpath("", $0)); }

'
}

unlinked()
{
	local sep="@@@"
	(
		build_list -i
		echo "$sep"
		find . -type f -print
	) | awk -v "sep=$sep" '
	
	($0 == sep) { after_sep=1; next; }
	(!after_sep) { FOUND[$0]++ }

	{ sub("^./", "", $0) }

	'"$unlinked_ignores"'

	(after_sep) {
		if (!($0 in FOUND))
			print $0
	}
	'
}

### main ###

cmd="$1"
if test $# -gt 0
then
	shift 1
fi

case "$cmd"
in
	unlinked) unlinked "$@" ;;
	""|list) build_list "$@" ;;
	*) echo "unknown command $cmd" >&2; exit 1;;
esac