/* source.c -- Source code management for Libmaa
 * Created: Mon Dec 26 19:42:03 1994 by faith@dict.org
 * Copyright 1994-1998, 2002 Rickard E. Faith (faith@dict.org)
 * Copyright 2002-2008 Aleksey Cheusov (vle@gmx.net)
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 * 
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 * 
 * \section{Source Code Management}
 *
 * \intro Most of the source code management routines are designed to be
 * called from within a lexical analyzer.  The routines support the storage
 * and retrieval of source code lines and source code token information.  A
 * single, global, source code management object is supported.
 *
 * \textbf{This documentation is incomplete.}
 *
 * \textbf{These routines have not been fully implemented.}
 *
 */

#include "maaP.h"

typedef struct source {
	const char *file;
	int        line;
	int        offset;
	int        length;
	int        index;
} sourceType;

#define INCREMENT 1000

static const char **Lines;
static int        Count;
static int        Used;
static sourceType Info;
static mem_String StringHeap;
static mem_Object InfoHeap;

/* \doc The |src_create| functions initializes the global source code
   management object.  This routine should only be called once, if at all.
   If the other routines are used as expected, |src_create| will be called
   automatically when it is needed. */

void src_create(void)
{
	if (Lines)
		err_fatal(__func__, "Source manager already created");

	Lines      = xmalloc((Count = INCREMENT) * sizeof(char *));
	StringHeap = mem_create_strings();
	InfoHeap   = mem_create_objects(sizeof(struct source));
}

/* \doc |src_destroy| frees all memory associated with the global source
   code management object. */

void src_destroy(void)
{
	if (!Lines) return;
	mem_destroy_objects(InfoHeap);
	mem_destroy_strings(StringHeap);
	xfree(Lines);		/* terminal */
	Lines = StringHeap = InfoHeap = NULL;
}

/* \doc |src_line| stores a |line| of length |len|. */

const char *src_line(const char *line, int len)
{
	char *pt;
   
	if (!Lines) src_create();
   
	++Info.line;
	Info.index  = Used;
	Info.offset = 0;
   
	Lines[Used] = mem_strncpy(StringHeap, line, len);
	for (pt = (char*)__UNCONST(Lines[Used]); *pt; pt++) if (*pt == '\t') *pt = ' ';
   
	PRINTF(MAA_SRC,("Line %d: %s",Used,Lines[Used]));
   
	if (++Used >= Count)
		Lines = xrealloc(Lines, (Count += INCREMENT) * sizeof(char *));
   
	return Lines[ Used - 1 ];
}

/* \doc |src_new_file| specifies that |filename| is the name of the current
   file being read by the lexer. */

void src_new_file(const char *filename)
{
   Info.file = str_find(filename);
}

/* \doc |src_new_line| specifies that |line| is the number of the current
   line being read by the lexer.  Line numbers start at 1. */

void src_new_line(int line)
{
	Info.line = line;
}

/* \doc |src_advance| is used to advance the token offset pointer |length|
   bytes. */

void src_advance(int length)
{
	Info.offset += length;
}

void src_cpp_line(const char *line, int length)
{
	arg_List args;
	char     *tmp = alloca(length + 1);
	int      lineno;

	strncpy(tmp, line, length);
	tmp [ length ] = '\0';

	args = arg_argify(tmp, 0);

	if ((lineno = atoi(arg_get(args, 1))) > 0) --lineno;
	else                                           lineno = 1;
	src_new_line(lineno);

	/* FIXME! This is debugging cruft to be
	   removed. */
	if (arg_count(args) == 2) {
		PRINTF(MAA_SRC,("lineno %s\n", arg_get(args, 1)));
	} else {
		PRINTF(MAA_SRC,("lineno %s in %s\n",
						arg_get(args, 1), arg_get(args, 2)));
		src_new_file(arg_get(args, 2));
	}
   
	arg_destroy(args);
}

/* \doc |src_get| is used to get a |src_Type| object for the current token.
   This object contains file, line, offset, and length information which
   can be used to print parse error messages and provide detailed token
   tracking. */

src_Type src_get(int length)
{
	sourceType *new;

	if (!Lines)
		err_fatal(__func__, "Source manager does not exist");
   
	Info.length = length;
	new = mem_get_object(InfoHeap);

	new->file   = Info.file;
	new->line   = Info.line;
	new->offset = Info.offset;
	new->length = Info.length;
	new->index  = Info.index;	/* Index into Lines array. */

	if (dbg_test(MAA_SRC)) {
		printf("%s:%d @ %d, %d; %d\n",
			   new->file,
			   new->line,
			   new->offset,
			   new->length,
			   new->index);
	}

	src_advance(length);

	return new;
}

/* \doc |src_filename| returns the |file| associated with the specified
   |source| information. */

const char *src_filename(src_Type source)
{
	sourceType *s = (sourceType *)source;

	if (!Lines)
		err_fatal(__func__, "Source manager never created");

	return s ? s->file : "";
}

/* \doc |src_linenumber| returns the |line| associated with the specified
   |source| information. */

int src_linenumber(src_Type source)
{
	sourceType *s = (sourceType *)source;

	if (!Lines)
		err_fatal(__func__, "Source manager never created");

	return s ? s->line : 0;
}

/* \doc |src_offset| returns the token |offset| associated with the
   specified |source| information. */

int src_offset(src_Type source)
{
	sourceType *s = (sourceType *)source;

	if (!Lines)
		err_fatal(__func__, "Source manager never created");

	return s ? s->offset : 0;
}

/* \doc |src_length| returns the token |length| associated with the
   specified |source| information. */

int src_length(src_Type source)
{
	sourceType *s = (sourceType *)source;

	if (!Lines)
		err_fatal(__func__, "Source manager never created");

	return s ? s->length : 0;
}

/* \doc |src_source_line| returns the full source line associated with the
   specified |source| information. */

const char *src_source_line(src_Type source)
{
	sourceType *s = (sourceType *)source;

	if (!Lines)
		err_fatal(__func__, "Source manager never created");

	return s ? Lines[ s->index ] : "";
}

/* \doc |src_get_stats| returns the statistics associated with the source
   code manager.  The |src_Stats| structure is shown in
   \grind{src_Stats}. */

src_Stats src_get_stats(void)
{
	src_Stats s = xmalloc(sizeof(struct src_Stats));

	if (Lines) {
		mem_StringStats ms = mem_get_string_stats(StringHeap);
		mem_ObjectStats mo = mem_get_object_stats(InfoHeap);
	  
		s->lines_used      = Used;
		s->lines_allocated = Count;
		s->lines_bytes     = ms->bytes;
		s->tokens_total    = mo->total;
		s->tokens_reused   = mo->reused;
		s->tokens_size     = mo->size;

		xfree(ms);		/* rare */
		xfree(mo);		/* rare */
	} else {
		s->lines_used      = 0;
		s->lines_allocated = 0;
		s->lines_bytes     = 0;
		s->tokens_total    = 0;
		s->tokens_reused   = 0;
		s->tokens_size     = 0;
	}

	return s;
}

/* \doc |src_print_stats| prints the statistics about the source code
   manager to the specified |stream|.  If |stream| is "NULL", then "stdout"
   will be used. */

void src_print_stats(FILE *stream)
{
	FILE      *str = stream ? stream : stdout;
	src_Stats s    = src_get_stats();

	fprintf(str, "Statistics for source manager:\n");
	fprintf(str, "   %d lines using %d bytes (%d allocated)\n",
			s->lines_used, s->lines_bytes, s->lines_allocated);
	fprintf(str, "   %d tokens using %d bytes (%d reused)\n",
			s->tokens_total, s->tokens_total * s->tokens_size,
			s->tokens_reused);
	xfree(s);			/* rare */
}

static void _src_print_yyerror(FILE *str, const char *message)
{
	const char *pt;
	char       buf[1024];
	char       *b;
	const char *concrete;

	assert(str);
   
	if (!message) {
		fprintf(str, "(null)");
		return;
	}

	for (pt = message; *pt; pt++) {
		if (*pt == '`') {		/* clean up character constants */
			if (pt[1] == '`' && pt[2] && pt[3] == '\'' && pt[4] == '\'') {
				fprintf(str, "`%c'", pt[2]);
				pt += 4;
			} else if (pt[1] == 'T' && pt[2] == '_') { /* replace symbols */
				for (b = buf, ++pt; *pt && *pt != '\''; b++, pt++) *b = *pt;
				*b = '\0';
				if ((concrete = prs_concrete(buf)))
					fprintf(str, "`%s'", concrete);
				else
					fprintf(str, "`%s'", buf);
			} else
				putc(*pt, str);
		} else
			putc(*pt, str);
	}
}

/* \doc |src_print_line| prints a line of source code, as described by
   |source| to the specified |stream|.  If |stream| is "NULL", then
   "stdout" will be used. */

void src_print_line(FILE *stream, src_Type source)
{
	sourceType *s   = (sourceType *)source;
	FILE       *str = stream ? stream : stdout;

	if (s)
		fprintf(str, "%s:%d: %s", s->file, s->line, Lines[ s->index ]);
	else
		fprintf(str, "?:?: <source line not available>\n");
}

static void _src_print_error(FILE *str, sourceType *s, int fudge)
{
	int        i;

	assert(str);

	src_print_line(str, s);
	if (s) {
		PRINTF(MAA_SRC,("s->offset = %d, fudge = %d, s->length = %d\n",
						s->offset, fudge, s->length));
		fprintf(str, "%s:%d: ", s->file, s->line);
		for (i = 0; i < s->offset - fudge; i++) putc(' ', str);
		for (i = 0; i < s->length; i++) putc('^', str);
	} else {
		fprintf(str, "?:?: ");
	}
	putc('\n', str);
}

/* \doc |src_parse_error| will print the error |message| to the specified
   |stream|, followed by the offending line of source code, as specified by
   |source|.  If |stream| is "NULL", then "stdout" will be used.

   It is assumed that |message| has the format of |yyerror| so that
   massaging of the string can be performed to make it more readable (token
   names are assumed to start with ``T\_'' and will be changed to more
   readable names).  This massaging should be done by a user-defined
   function, since it is relatively specific to this author's coding
   conventions. */

void src_parse_error(FILE *stream, src_Type source, const char *message)
{
	sourceType *s   = (sourceType *)source;
	FILE       *str = stream ? stream : stdout;

	if (s) fprintf(str, "%s:%d: ", s->file, s->line);
	else   fprintf(str, "?:?: ");
	_src_print_yyerror(str, message);
	putc('\n', str);

	_src_print_error(str, s, 0);
}

/* \doc |src_print_error| will print an arbitrary error, specified as for
   |printf| by the |format| variable, to the specified |stream|, followed
   by the line of source code specified by |source|.  If |stream| is
   "NULL", then "stdout" will be used. */

void src_print_error(FILE *str, src_Type source, const char *format, ...)
{
	va_list    ap;
	sourceType *s = (sourceType *)source;

	fflush(str);
	if (format) {
		if (s)
			fprintf(str, "%s:%d: ", s->file, s->line);
		else
			fprintf(str, "?:?: ");
		va_start(ap, format);
		vfprintf(str, format, ap);
		va_end(ap);
		putc('\n', str);
	}
   
	_src_print_error(str, s, 0);
}

/* \doc |src_print_message| will just print a message labeled with a line. */

void src_print_message(FILE *str, src_Type source, const char *format, ...)
{
	va_list    ap;
	sourceType *s = (sourceType *)source;

	fflush(str);
	if (format) {
		if (s)
			fprintf(str, "%s:%d: ", s->file, s->line);
		else
			fprintf(str, "?:?: ");
		va_start(ap, format);
		vfprintf(str, format, ap);
		va_end(ap);
		putc('\n', str);
	}
}