#!/usr/bin/awk -f

BEGIN {
	fieldstr = "pkgname _ver pkgver pkgrel pkgdesc epoch" \
		" *arch *license *options" \
		" install changelog" \
		" *depends *makedepends *checkdepends *optdepends" \
		" *conflicts *provides" \
		" url *source *noextract *md5sums *sha512sums"
	fcount = split(fieldstr, fields)
	for(i = 1; i <= fcount; i++){
		f = fields[i]
		if(sub(/^[*]/, "", f)){
			fields[i] = f
			arrfield[f] = 1
		}else{
			strfield[f] = 1
		}
	}

	COLS = 78; FS = "\n"; RS = ""
}

NF < 2 { next }

$1 == "packager" { packager = $2; next }

$1 == "maintainer" { maintainer = $2; next }

# pkgdesc has the only value where parameters do not expand.
$1 == "pkgdesc" { values[$1] = qnoexpand($2); next }

{
	for(i = 2; i <= NF; i++) $i = qexpand($i)
	if($1 in strfield){
		values[$1] = $2
	}else if($1 in arrfield){
		values[$1] = wraparray(length($1) + 2)
	}else if($1 ~ /^_/){
		vars[++vcount] = $1
		if(NF > 2){
			values[$1] = wraparray(length($1) + 2)
		}else{
			values[$1] = $2
		}
	}
}

END {
	if(maintainer){
		print "# Maintainer: " maintainer "\n"
	}else if(packager){
		print "# Packager: " packager "\n"
	}else{
		print "# Packager: Anonymous\n"
	}

	ORS = "\n";

	# Loop through our list of PKGBUILD field names so they are always
	# printed in the same order, matching the PKGBUILD manpage.
	for(i = 1; i <= fcount; i++){
		f = fields[i]
		if(!(f in values)){
			continue
		}
		v = values[f]
		print f "=" v
	}

	# Print our custom variables in the order they appeared.
	for(i = 1; i <= vcount; i++){
		v = vars[i]
		print v "=" values[v]
	}
}

function wraparray (indent)
{
	if(NF == 1) return "()" # this shouldn't happen but just in case.

	line = ""
	delete lines
	linecount = 0

	i = 2
	while(i <= NF){
		linelen = length(line)

		if((indent + linelen + 1 + length($i) > COLS) && linelen > 0){
			lines[++linecount] = line
			line = ""
		}else{
			if(linelen == 0) line = $(i++)
			else line = line " " $(i++)
		}
	}

	if(length(line) > 0) lines[++linecount] = line

	indtxt = sprintf("%" indent "s", "")
	txt = "(" lines[1]
	for(i=2; i<=linecount; i++) txt = txt "\n" indtxt lines[i]
	txt = txt ")"

	return txt
}

# Quote field value so that parameters ARE expanded.
# NEVER expand command substition (ie backtick or $(...))
function qexpand (v)
{
	if(v ~ /[$']/){
		gsub(/["`]/, "\\\\&", v)
		gsub(/[$][(]/, "\\$(", v)
		return sprintf("\"%s\"", v)
	}else if(v ~ /[ <>`"]/){
		return sprintf("'%s'", v)
	}else{
		return v
	}
}

# Quote field value so that parameters ARE NOT expanded.
function qnoexpand (v)
{
	if(v ~ /'/){
		gsub(/[$"`]/, "\\\\&", v)
		return sprintf("\"%s\"", v)
	}else if(v ~ /[ $"`<>]/){
		return sprintf("'%s'", v)
	}else{
		return v
	}
}