/*
	pr_debug.c

	progs debugging

	Copyright (C) 2001       Bill Currie <bill@tanwiha.org>

	Author: Bill Currie <bill@tanwiha.org>
	Date: 2001/7/13

	This program is free software; you can redistribute it and/or
	modify it under the terms of the GNU General Public License
	as published by the Free Software Foundation; either version 2
	of the License, or (at your option) any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

	See the GNU General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with this program; if not, write to:

		Free Software Foundation, Inc.
		59 Temple Place - Suite 330
		Boston, MA  02111-1307, USA

*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

static __attribute__ ((unused)) const char rcsid[] = 
	"$Id$";

#ifdef HAVE_STRING_H
# include <string.h>
#endif
#ifdef HAVE_STRINGS_H
# include <strings.h>
#endif

#include <stdlib.h>

#include "QF/cvar.h"
#include "QF/dstring.h"
#include "QF/hash.h"
#include "QF/pr_debug.h"
#include "QF/progs.h"
#include "QF/qendian.h"
#include "QF/quakefs.h"
#include "QF/sys.h"
#include "QF/zone.h"

#include "compat.h"

typedef struct {
	char *text;
	size_t len;
} line_t;

typedef struct {
	char *name;
	char *text;
	line_t *lines;
	unsigned int num_lines;
	progs_t *pr;
} file_t;

cvar_t         *pr_debug;
cvar_t         *pr_source_path;
static hashtab_t   *file_hash;
static char        *source_path_string;
static char       **source_paths;


static const char *
file_get_key (void *_f, void *unused)
{
	return ((file_t*)_f)->name;
}

static void
file_free (void *_f, void *unused)
{
	file_t     *f = (file_t*)_f;
	progs_t    *pr = f->pr;

	free (f->lines);
	((progs_t *) pr)->free_progs_mem (pr, f->text);
	free (f->name);
	free (f);
}

static void
source_path_f (cvar_t *var)
{
	int         i;
	char       *s;

	if (source_path_string)
		free (source_path_string);
	source_path_string = strdup (var->string);
	if (source_paths)
		free (source_paths);
	for (i = 2, s = source_path_string; *s; s++)
		if (*s == ';')
			i++;
	source_paths = malloc (i * sizeof (char **));
	source_paths[0] = source_path_string;
	for (i = 1, s = source_path_string; *s; s++)
		if (*s == ';') {
			*s++ = 0;
			source_paths[i++] = s;
		}
	source_paths[i] = 0;
}

void
PR_Debug_Init (void)
{
	file_hash = Hash_NewTable (1024, file_get_key, file_free, 0);
}

void
PR_Debug_Init_Cvars (void)
{
	pr_debug = Cvar_Get ("pr_debug", "0", CVAR_NONE, NULL,
						 "enable progs debugging");
	pr_source_path = Cvar_Get ("pr_source_path", ".", CVAR_NONE, source_path_f,
							   "where to look (within gamedir) for source "
							   "files");
}

static file_t *
PR_Load_Source_File (progs_t *pr, const char *fname)
{
	char       *path = 0, *l, **dir;
	file_t     *f = Hash_Find (file_hash, fname);

	if (f)
		return f;
	f = calloc (1, sizeof (file_t));
	if (!f)
		return 0;
	for (dir = source_paths; *dir && !f->text; dir++) {
		int         len;
		len = strlen (*dir) + strlen (fname) + 2;
		path = Hunk_TempAlloc (len);
		sprintf (path, "%s%s%s", *dir, **dir ? "/" : "", fname);
		f->text = pr->load_file (pr, path);
	}
	if (!f->text) {
		pr->file_error (pr, path);
		free (f);
		return 0;
	}
	for (f->num_lines = 1, l = f->text; *l; l++)
		if (*l == '\n')
			f->num_lines++;
	f->name = strdup (fname);
	if (!f->name) {
		pr->free_progs_mem (pr, f->text);
		free (f);
		return 0;
	}
	f->lines = malloc (f->num_lines * sizeof (line_t));
	if (!f->lines) {
		free (f->name);
		pr->free_progs_mem (pr, f->text);
		free (f);
		return 0;
	}
	f->lines[0].text = f->text;
	for (f->num_lines = 0, l = f->text; *l; l++) {
		if (*l == '\n') {
			f->lines[f->num_lines].len = l - f->lines[f->num_lines].text;
			f->lines[++f->num_lines].text = l + 1;
		}
	}
	f->lines[f->num_lines++].len = l - f->lines[f->num_lines].text;
	f->pr = pr;
	Hash_Add (file_hash, f);
	return f;
}

void
PR_LoadDebug (progs_t *pr)
{
	char		*sym_path;
	const char	*path_end, *sym_file;
	unsigned int i;
	int			start = Hunk_LowMark ();
	ddef_t	   *def;
	pr_type_t  *str = 0;

	pr->debug = 0;
	pr->auxfunctions = 0;
	pr->auxfunction_map = 0;
	pr->linenos = 0;
	pr->local_defs = 0;

	if (!pr_debug->int_val)
		return;

	def = PR_FindGlobal (pr, ".debug_file");
	if (def)
		str = &pr->pr_globals[def->ofs];

	Hash_FlushTable (file_hash);
	if (!str)
		return;
	pr->debugfile = PR_GetString (pr, str->string_var);
	sym_file = QFS_SkipPath (pr->debugfile);
	path_end = QFS_SkipPath (pr->progs_name);
	sym_path = Hunk_TempAlloc (strlen (sym_file) + (path_end - pr->progs_name)
							   + 1);
	strncpy (sym_path, pr->progs_name, path_end - pr->progs_name);
	strcpy (sym_path + (path_end - pr->progs_name), sym_file);
	pr->debug = pr->load_file (pr, sym_path);
	if (!pr->debug) {
		Sys_Printf ("can't load %s for debug info\n", sym_path);
		return;
	}
	pr->debug->version = LittleLong (pr->debug->version);
	if (pr->debug->version != PROG_DEBUG_VERSION) {
		Sys_Printf ("ignoring %s with unsupported version %x.%03x.%03x\n",
					sym_path,
					(pr->debug->version >> 24) & 0xff,
					(pr->debug->version >> 12) & 0xfff,
					pr->debug->version & 0xfff);
		Hunk_FreeToLowMark (start);
		pr->debug = 0;
		return;
	}
	pr->debug->crc = LittleShort (pr->debug->crc);
	if (pr->debug->crc != pr->crc) {
		Sys_Printf ("ignoring %s that doesn't match %s. (CRCs: "
					"sym:%d dat:%d)\n",
					sym_path,
					pr->progs_name,
					pr->debug->crc,
					pr->crc);
		Hunk_FreeToLowMark (start);
		pr->debug = 0;
		return;
	}
	pr->debug->you_tell_me_and_we_will_both_know = LittleShort
		(pr->debug->you_tell_me_and_we_will_both_know);
	pr->debug->auxfunctions = LittleLong (pr->debug->auxfunctions);
	pr->debug->num_auxfunctions = LittleLong (pr->debug->num_auxfunctions);
	pr->debug->linenos = LittleLong (pr->debug->linenos);
	pr->debug->num_linenos = LittleLong (pr->debug->num_linenos);
	pr->debug->locals = LittleLong (pr->debug->locals);
	pr->debug->num_locals = LittleLong (pr->debug->num_locals);

	pr->auxfunctions = (pr_auxfunction_t*)((char*)pr->debug +
										   pr->debug->auxfunctions);
	pr->linenos = (pr_lineno_t*)((char*)pr->debug + pr->debug->linenos);
	pr->local_defs = (ddef_t*)((char*)pr->debug + pr->debug->locals);

	pr->auxfunction_map = Hunk_Alloc (pr->progs->numfunctions *
									  sizeof (pr_auxfunction_t*));

	for (i = 0; i < pr->debug->num_auxfunctions; i++) {
		pr->auxfunctions[i].function = LittleLong
			(pr->auxfunctions[i].function);
		pr->auxfunctions[i].source_line = LittleLong
			(pr->auxfunctions[i].source_line);
		pr->auxfunctions[i].line_info = LittleLong
			(pr->auxfunctions[i].line_info);
		pr->auxfunctions[i].local_defs = LittleLong
			(pr->auxfunctions[i].local_defs);
		pr->auxfunctions[i].num_locals = LittleLong
			(pr->auxfunctions[i].num_locals);

		pr->auxfunction_map[pr->auxfunctions[i].function] =
			&pr->auxfunctions[i];
	}
	for (i = 0; i < pr->debug->num_linenos; i++) {
		pr->linenos[i].fa.func = LittleLong (pr->linenos[i].fa.func);
		pr->linenos[i].line = LittleLong (pr->linenos[i].line);
	}
	for (i = 0; i < pr->debug->num_locals; i++) {
		pr->local_defs[i].type = LittleShort (pr->local_defs[i].type);
		pr->local_defs[i].ofs = LittleShort (pr->local_defs[i].ofs);
		pr->local_defs[i].s_name = LittleLong (pr->local_defs[i].s_name);
	}
}

pr_auxfunction_t *
PR_Get_Lineno_Func (progs_t *pr, pr_lineno_t *lineno)
{
	while (lineno > pr->linenos && lineno->line)
		lineno--;
	if (lineno->line)
		return 0;
	return &pr->auxfunctions[lineno->fa.func];
}

unsigned int
PR_Get_Lineno_Addr (progs_t *pr, pr_lineno_t *lineno)
{
	pr_auxfunction_t *f;

	if (lineno->line)
		return lineno->fa.addr;
	f = &pr->auxfunctions[lineno->fa.func];
	return pr->pr_functions[f->function].first_statement;
}

unsigned int
PR_Get_Lineno_Line (progs_t *pr, pr_lineno_t *lineno)
{
	pr_auxfunction_t *f;

	if (lineno->line)
		return lineno->line;
	f = &pr->auxfunctions[lineno->fa.func];
	return f->source_line;
}

pr_lineno_t *
PR_Find_Lineno (progs_t *pr, unsigned int addr)
{
	int				i;
	pr_lineno_t	   *lineno = 0;

	if (!pr->debug)
		return 0;
	if (!pr->debug->num_linenos)
		return 0;
	for (i = pr->debug->num_linenos - 1; i >= 0; i--) {
		if (PR_Get_Lineno_Addr (pr, &pr->linenos[i]) <= addr) {
			lineno = &pr->linenos[i];
			break;
		}
	}
	return lineno;
}

const char *
PR_Get_Source_File (progs_t *pr, pr_lineno_t *lineno)
{
	pr_auxfunction_t *f;

	f = PR_Get_Lineno_Func (pr, lineno);
	return PR_GetString(pr, pr->pr_functions[f->function].s_file);
}

const char *
PR_Get_Source_Line (progs_t *pr, unsigned int addr)
{
	char			   *str;
	const char		   *fname;
	unsigned int		line;
	file_t			   *file;
	pr_auxfunction_t   *func;
	pr_lineno_t        *lineno;
	
	lineno = PR_Find_Lineno (pr, addr);
	if (!lineno || PR_Get_Lineno_Addr (pr, lineno) != addr)
		return 0;
	func = PR_Get_Lineno_Func (pr, lineno);
	fname = PR_Get_Source_File (pr, lineno);
	if (!func || !fname)
		return 0;
	line = PR_Get_Lineno_Line (pr, lineno);
	line += func->source_line;

	file = PR_Load_Source_File (pr, fname);

	str = Hunk_TempAlloc (strlen (fname) + 12);
	sprintf (str, "%s:%d", fname, line);

	if (!file || line > file->num_lines)
		return str;

	str = Hunk_TempAlloc (strlen (str) + file->lines[line - 1].len + 2);
	sprintf (str, "%s:%d:%.*s", fname, line,
			 (int)file->lines[line - 1].len, file->lines[line - 1].text);
	return str;
}

ddef_t *
PR_Get_Local_Def (progs_t *pr, int offs)
{
	unsigned int		i;
	dfunction_t		   *func = pr->pr_xfunction;
	pr_auxfunction_t   *aux_func;

	if (!func)
		return 0;
	aux_func = pr->auxfunction_map[func - pr->pr_functions];
	if (!aux_func)
		return 0;
	offs -= func->parm_start;
	if (offs < 0 || offs >= func->locals)
		return 0;
	for (i = 0; i < aux_func->num_locals; i++)
		if (pr->local_defs[aux_func->local_defs + i].ofs == offs)
			return &pr->local_defs[aux_func->local_defs + i];
	return 0;
}

void
PR_DumpState (progs_t *pr)
{
	if (pr->pr_xfunction) {
		if (pr_debug->int_val && pr->debug) {
			pr_lineno_t *lineno;
			pr_auxfunction_t *func = 0;
			int         addr = pr->pr_xstatement;

			lineno = PR_Find_Lineno (pr, addr);
			if (lineno)
				func = PR_Get_Lineno_Func (pr, lineno);
			if (func && pr->pr_xfunction == pr->pr_functions + func->function)
				addr = PR_Get_Lineno_Addr (pr, lineno);
			else
				addr = max (pr->pr_xfunction->first_statement, addr - 5);

			while (addr != pr->pr_xstatement)
				PR_PrintStatement (pr, pr->pr_statements + addr++);
		}
		PR_PrintStatement (pr, pr->pr_statements + pr->pr_xstatement);
	}
	PR_StackTrace (pr);
}

void
PR_PrintStatement (progs_t * pr, dstatement_t *s)
{
	int			addr = s - pr->pr_statements;
	const char *fmt;
	opcode_t	*op;
	static dstring_t *line;

	if (!line)
		line = dstring_new ();

	dstring_clearstr (line);

	if (pr_debug->int_val && pr->debug) {
		const char *source_line = PR_Get_Source_Line (pr, addr);

		if (source_line)
			dasprintf (line, "%s\n", source_line);
	}

	op = PR_Opcode (s->op);
	if (!op) {
		Sys_Printf ("%sUnknown instruction %d\n", line->str, s->op);
		return;
	}

	if (!(fmt = op->fmt))
		fmt = "%Ga, %Gb, %gc";

	dasprintf (line, "%04x ", addr);
	if (pr_debug->int_val > 1)
		dasprintf (line, "%02x %04x(%8s) %04x(%8s) %04x(%8s)\t",
					s->op,
					s->a, pr_type_name[op->type_a],
					s->b, pr_type_name[op->type_b],
					s->c, pr_type_name[op->type_c]);

	dasprintf (line, "%s ", op->opname);

	while (*fmt) {
		if (*fmt == '%') {
			if (fmt[1] == '%') {
				dstring_appendsubstr (line, fmt + 1, 1);
				fmt += 2;
			} else {
				char        mode = fmt[1];
				char        opchar = fmt[2];
				long        opval;
				etype_t     optype;

				switch (opchar) {
					case 'a':
						opval = s->a;
						optype = op->type_a;
						break;
					case 'b':
						opval = s->b;
						optype = op->type_b;
						break;
					case 'c':
						opval = s->c;
						optype = op->type_c;
						break;
					default:
						goto err;
				}
				switch (mode) {
					case 'V':
						dstring_appendstr (line,
										   PR_GlobalString (pr, opval,
											   				ev_void));
						break;
					case 'G':
						dstring_appendstr (line,
										   PR_GlobalString (pr, opval,
											   				optype));
						break;
					case 'g':
						dstring_appendstr (line,
										   PR_GlobalStringNoContents (pr,
											   						  opval,
																	  optype));
						break;
					case 's':
						dasprintf (line, "%d", (short) opval);
						break;
					case 'O':
						dasprintf (line, "%04x", addr + (short) opval);
						break;
					default:
						goto err;
				}
				fmt += 3;
				continue;
			err:
				dstring_appendstr (line, fmt);
				break;
			}
		} else {
			dstring_appendsubstr (line, fmt++, 1);
		}
	}
	Sys_Printf ("%s\n", line->str);
}

void
PR_StackTrace (progs_t * pr)
{
	int				i;
	dfunction_t	   *f;

	if (pr->pr_depth == 0) {
		Sys_Printf ("<NO STACK>\n");
		return;
	}

	pr->pr_stack[pr->pr_depth].s = pr->pr_xstatement;
	pr->pr_stack[pr->pr_depth].f = pr->pr_xfunction;
	for (i = pr->pr_depth; i >= 0; i--) {
		f = pr->pr_stack[i].f;

		if (!f) {
			Sys_Printf ("<NO FUNCTION>\n");
		} else {
			if (pr_debug->int_val && pr->debug) {
				pr_lineno_t *lineno = PR_Find_Lineno (pr, pr->pr_stack[i].s);
				pr_auxfunction_t *func = PR_Get_Lineno_Func (pr, lineno);
				unsigned int line = PR_Get_Lineno_Line (pr, lineno);
				int         addr = PR_Get_Lineno_Addr (pr, lineno);

				line += func->source_line;
				if (addr == pr->pr_stack[i].s) {
					Sys_Printf ("%12s:%d : %s: %x\n",
								PR_GetString (pr, f->s_file),
								line,
								PR_GetString (pr, f->s_name),
								pr->pr_stack[i].s);
				} else {
					Sys_Printf ("%12s:%d+%d : %s: %x\n",
								PR_GetString (pr, f->s_file),
								line, pr->pr_stack[i].s - addr,
								PR_GetString (pr, f->s_name),
								pr->pr_stack[i].s);
				}
			} else {
				Sys_Printf ("%12s : %s: %x\n", PR_GetString (pr, f->s_file),
							PR_GetString (pr, f->s_name), pr->pr_stack[i].s);
			}
		}
	}
}

void
PR_Profile (progs_t * pr)
{
	int				max, num, i;
	dfunction_t	   *best, *f;

	num = 0;
	do {
		max = 0;
		best = NULL;
		for (i = 0; i < pr->progs->numfunctions; i++) {
			f = &pr->pr_functions[i];
			if (f->profile > max) {
				max = f->profile;
				best = f;
			}
		}
		if (best) {
			if (num < 10)
				Sys_Printf ("%7i %s\n", best->profile,
							PR_GetString (pr, best->s_name));
			num++;
			best->profile = 0;
		}
	} while (best);
}