#!/bin/sh

# simple shader parsing "framework"

shader_normalize()
{
	echo "$1" | sed 's/\.\(tga\|jpg\|png\)$//'
}

parse_shaderstage_pre()
{
	: replace this function after including
}
parse_shaderstage_line()
{
	: replace this function after including
}
parse_shaderstage_post()
{
	: replace this function after including
}
parse_shaderstage()
{
	parse_shaderstage_pre
	while read shaderparser_L shaderparser_A1 shaderparser_Aother; do
		case "`echo "$shaderparser_L" | tr A-Z a-z`" in
			'{')
				err "brace nesting error in $parsing_shader"
				;;
			'}')
				break
				;;
			'')
				;;
			*)
				parse_shaderstage_line "$shaderparser_L" "$shaderparser_A1" "$shaderparser_Aother"
				;;
		esac
	done
	parse_shaderstage_post
}

parse_shader_pre()
{
	: replace this function after including
}
parse_shader_line()
{
	: replace this function after including
}
parse_shader_post()
{
	: replace this function after including
}
parse_shader()
{
	parse_shader_pre
	while read shaderparser_L shaderparser_A1 shaderparser_Aother; do
		case "`echo "$shaderparser_L" | tr A-Z a-z`" in
			'{')
				parse_shaderstage
				;;
			'}')
				break
				;;
			'')
				;;
			*)
				parse_shader_line "$shaderparser_L" "$shaderparser_A1" "$shaderparser_Aother"
				;;
		esac
	done
	parse_shader_post
}

parse_shaderfile_pre()
{
	: replace this function after including
}
parse_shaderfile_post()
{
	: replace this function after including
}
parse_shaderfile()
{
	parse_shaderfile_pre
	while read shaderparser_L; do
		case "$shaderparser_L" in
			'{')
				parse_shader
				;;
			'{')
				err "brace nesting error in $parsing_shader"
				;;
			'')
				;;
			*)
				parsing_shader="`shader_normalize "$shaderparser_L"`"
				if [ x"$shaderparser_L" != x"$parsing_shader" ]; then
					warn "normalized shader name $shaderparser_L to $parsing_shader"
				fi
				;;
		esac
	done
	parse_shaderfile_post
}

shaderparser_strip_comments()
{
	sed 's,//.*,,g; s,\r, ,g; s,\shaderparser_t, ,g; s,  *, ,g; s, $,,; s,^ ,,; /^$/ d'
}

parse_shaders()
{
	shaderparser_t=`mktemp || echo ".temp"`
	for shaderparser_X in "$@"; do
		shaderparser_strip_comments < "$shaderparser_X" > "$shaderparser_t"
		parsing_shaderfile="$shaderparser_X"
		parse_shaderfile < "$shaderparser_t"
	done
	rm -f "$shaderparser_t"
}