/************************************************************************
* awk.e                                                                 *
* "Epsilon" is a registered trademark licensed to Lugaru Software, Ltd. *
*		"EEL" and "Lugaru" are trademarks of Lugaru Software, Ltd.		*
*																		*
*  Copyright (C) 1996, 1997 Lugaru Software Ltd.  All rights reserved.  *
*																		*
* Limited permission is hereby granted to reproduce and modify this		*
* copyrighted material provided that the resulting code is used only in *
* conjunction with Lugaru products and that this notice is retained in	*
* any such reproduction or modification.								*
* ***********************************************************************
* Modified by Paul Neth, Jan 14, 1998  email:pneth@henge.com            *
* Modified the assembly language eel (asm.e) program                    *
* from the lugaru web site                                              *
* Provides syntax highlighting for GNU awk programs                     *
* Highlites the awk keywords in blue.                                   *
* Comments are in green and strings are in red.                         *
************************************************************************/

#include "eel.h"
#include "proc.h"
#include "colcode.h"

char _awk_mode_name[] = "awk";	/* awk mode */
keytable awk_tab;				/* key table for awk mode */

color_scheme "standard-gui" {		/* define some of the colors */
	color_class awk_keyword blue;
	color_class awk_identifier black;
};

color_awk_range(from, to) // recolor just this section
{			// last colored region may go past to
	int t = -1, talk, s;
	if (from >= to)
		return to;
	save_var point, matchstart, matchend;
	c_init_color(from, to);
	point = from;
	talk = (to - from > 2000);	// show status during long delays
	save_var case_fold = 0;
	while (point < to) {
		if (!re_search(1, "[0-9A-Za-z_.]+|[\"';#]")) {
			t = size();
			break;
		}
		t = matchstart;
		switch (character(point - 1)) {		// check last char
			case '#':		// found a pound sign (starts a comment)
				nl_forward();
				set_character_color(t, point, color_class c_comment);
				break;
			case '"':		// found a string literal
				point = t;
				re_search(1, "\"([^\"\\\n]|\\(.|\n))*[\"\n]");
				set_character_color(t, point, color_class c_string);
				if (get_character_color(point, (int *) 0, &s) == 
					color_class c_string && s > to)  // fix up after
					c_init_color(point, to = s); // quoted "'s
				break;
			default:		// found identifier, kywd, or number
				set_character_color(t, point, awk_keyword_color(t));
				break;
		}
		if (talk)
			note("Coloring awk program: %d%% complete...",
				 (point - from) * 100 / (to - from));
	}
	c_init_color(to, t);
	if (talk)
		note("");
	return point;
}

awk_keyword_color(from)	// return color for "identifier" from here to point
{			// (something with alpha or digits)
	char buf[500];

	if (point - from > sizeof(buf) - 10)
		save_var point = from + sizeof(buf) - 10;
	buf[0] = '|';		// get identifier, between | chars
	grab(from, point, buf + 1);
	if (index("0123456789-.", buf[1]))
		return c_number_color(buf + 1);
	strcpy(buf + point - from + 1, "|");
	if (is_awk_keyword(buf))
		return color_class awk_keyword;
	return color_class awk_identifier;
}

// gnu awk keyword list
is_awk_keyword(p)	// is text in p (must be surrounded by |'s) a keyword?
char *p;
{
	if (strstr("|ARGC|ARGIND|ARGV"
"|CONVFMT|FIELDWIDTHS|ENVIRON|"
"|ERRNO|FILENAME|FNR|"
"FS|IGNORECASE|NF|"
"NR|OFMT|OFS|"
"ORS|RS|RT|"
"RSTART|RLENGTH|SUBSEP|"
"BEGIN|END|"
"if|else|while|"
"do|for|break|"
"continue|delete|exit|"
"getline|next|nextfile|"
"print|printf|"
"atan2|cos|exp|"
"int|log|rand|"
"sin|sqrt|srand|"
"gensub|gsub|index|"
"length|match|split|"
"sprintf|sub|substr|"
"tolower|toupper|close|"
"fflush|system|systime|"
"strftime",p))
		return 1;
	return 0;
}

// A recolor_from_here function good for line-based buffers.
recolor_by_lines(safe)
{
	safe = safe;		// eliminate compiler warning
	return give_begin_line();
}

command awk_mode()
{
	mode_keys = awk_tab;		/* Use these keys. */
	major_mode = _awk_mode_name;
	strcpy(comment_start, "#");			// regex for start of comment
	strcpy(comment_pattern, ".*#.*$");	// regex pattern for comment area
	strcpy(comment_begin, "# ");		// string used if epsilon automatically creates comment
	strcpy(comment_end, "");			// string used to indicate end of string
	recolor_range = color_awk_range;	// set up coloring rules
	recolor_from_here = recolor_by_lines;
	if (want_code_coloring)			// maybe turn on coloring
		when_setting_want_code_coloring();
	try_calling("awk-mode-hook");
	make_mode();
}

suffix_awk()
{
	awk_mode();
}