/***********************************************************
Copyright 1991, 1992, 1993 by Stichting Mathematisch Centrum,
Amsterdam, The Netherlands.

                        All Rights Reserved

Permission to use, copy, modify, and distribute this software and its 
documentation for any purpose and without fee is hereby granted, 
provided that the above copyright notice appear in all copies and that
both that copyright notice and this permission notice appear in 
supporting documentation, and that the names of Stichting Mathematisch
Centrum or CWI not be used in advertising or publicity pertaining to
distribution of the software without specific, written prior permission.

STICHTING MATHEMATISCH CENTRUM DISCLAIMS ALL WARRANTIES WITH REGARD TO
THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH CENTRUM BE LIABLE
FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

******************************************************************/

/* Python interpreter top-level routines, including init/exit */

#include "allobjects.h"

#include "grammar.h"
#include "node.h"
#include "parsetok.h"
#include "graminit.h"
#include "errcode.h"
#include "sysmodule.h"
#include "compile.h"
#include "eval.h"
#include "ceval.h"
#include "pythonrun.h"
#include "import.h"

#ifdef unix
#define HANDLE_SIGNALS
#endif

#ifdef HANDLE_SIGNALS
#include <signal.h>
#include "sigtype.h"
#endif

extern char *getpythonpath();

extern grammar gram; /* From graminit.c */

/* Forward */
static object *run_err_node PROTO((int err, node *n, char *filename,
				   object *globals, object *locals));
static object *run_node PROTO((node *n, char *filename,
			       object *globals, object *locals));
static object *eval_node PROTO((node *n, char *filename,
				object *globals, object *locals));
void initsigs PROTO(());

int debugging; /* Needed by parser.c */
int verbose; /* Needed by import.c */

/* Initialize all */

void
initall()
{
	static int inited;
	
	if (inited)
		return;
	inited = 1;
	
	initimport();
	
	/* Modules 'builtin' and 'sys' are initialized here,
	   they are needed by random bits of the interpreter.
	   All other modules are optional and are initialized
	   when they are first imported. */
	
	initbuiltin(); /* Also initializes builtin exceptions */
	initsys();
	
	initcalls(); /* Configuration-dependent initializations */

	setpythonpath(getpythonpath());

	initsigs(); /* Signal handling stuff, including initintr() */
}

/* Parse input from a file and execute it */

int
run(fp, filename)
	FILE *fp;
	char *filename;
{
	if (filename == NULL)
		filename = "???";
	if (isatty((int)fileno(fp)))
		return run_tty_loop(fp, filename);
	else
		return run_script(fp, filename);
}

int
run_tty_loop(fp, filename)
	FILE *fp;
	char *filename;
{
	object *v;
	int ret;
	v = sysget("ps1");
	if (v == NULL) {
		sysset("ps1", v = newstringobject(">>> "));
		XDECREF(v);
	}
	v = sysget("ps2");
	if (v == NULL) {
		sysset("ps2", v = newstringobject("... "));
		XDECREF(v);
	}
	for (;;) {
		ret = run_tty_1(fp, filename);
#ifdef REF_DEBUG
		fprintf(stderr, "[%ld refs]\n", ref_total);
#endif
		if (ret == E_EOF)
			return 0;
		/*
		if (ret == E_NOMEM)
			return -1;
		*/
	}
}

int
run_tty_1(fp, filename)
	FILE *fp;
	char *filename;
{
	object *m, *d, *v, *w;
	node *n;
	char *ps1, *ps2;
	int err;
	v = sysget("ps1");
	w = sysget("ps2");
	if (v != NULL && is_stringobject(v)) {
		INCREF(v);
		ps1 = getstringvalue(v);
	}
	else {
		v = NULL;
		ps1 = "";
	}
	if (w != NULL && is_stringobject(w)) {
		INCREF(w);
		ps2 = getstringvalue(w);
	}
	else {
		w = NULL;
		ps2 = "";
	}
	BGN_SAVE
	err = parsefile(fp, filename, &gram, single_input, ps1, ps2, &n);
	END_SAVE
	XDECREF(v);
	XDECREF(w);
	if (err == E_EOF)
		return E_EOF;
	if (err != E_DONE) {
		err_input(err);
		print_error();
		return err;
	}
	m = add_module("__main__");
	if (m == NULL)
		return -1;
	d = getmoduledict(m);
	v = run_node(n, filename, d, d);
	flushline();
	if (v == NULL) {
		print_error();
		return -1;
	}
	DECREF(v);
	return 0;
}

int
run_script(fp, filename)
	FILE *fp;
	char *filename;
{
	object *m, *d, *v;
	m = add_module("__main__");
	if (m == NULL)
		return -1;
	d = getmoduledict(m);
	v = run_file(fp, filename, file_input, d, d);
	flushline();
	if (v == NULL) {
		print_error();
		return -1;
	}
	DECREF(v);
	return 0;
}

int
run_command(command)
	char *command;
{
	object *m, *d, *v;
	m = add_module("__main__");
	if (m == NULL)
		return -1;
	d = getmoduledict(m);
	v = run_string(command, file_input, d, d);
	flushline();
	if (v == NULL) {
		print_error();
		return -1;
	}
	DECREF(v);
	return 0;
}

void
print_error()
{
	object *exception, *v, *f;
	err_get(&exception, &v);
	if (exception == SystemExit) {
		if (v == NULL || v == None)
			goaway(0);
		if (is_intobject(v))
			goaway((int)getintvalue(v));
		else {
			/* OK to use real stderr here */
			printobject(v, stderr, PRINT_RAW);
			fprintf(stderr, "\n");
			goaway(1);
		}
	}
	sysset("last_type", exception);
	sysset("last_value", v);
	f = sysget("stderr");
	if (f == NULL)
		fprintf(stderr, "lost sys.stderr\n");
	else {
		printtraceback(f);
		if (writeobject(exception, f, PRINT_RAW) != 0)
			err_clear();
		if (v != NULL && v != None) {
			writestring(": ", f);
			if (writeobject(v, f, PRINT_RAW) != 0)
				err_clear();
		}
		writestring("\n", f);
	}
	XDECREF(exception);
	XDECREF(v);
}

object *
run_string(str, start, globals, locals)
	char *str;
	int start;
	object *globals, *locals;
{
	node *n;
	int err;
	err = parse_string(str, start, &n);
	return run_err_node(err, n, "<string>", globals, locals);
}

object *
run_file(fp, filename, start, globals, locals)
	FILE *fp;
	char *filename;
	int start;
	object *globals, *locals;
{
	node *n;
	int err;
	err = parse_file(fp, filename, start, &n);
	return run_err_node(err, n, filename, globals, locals);
}

static object *
run_err_node(err, n, filename, globals, locals)
	int err;
	node *n;
	char *filename;
	object *globals, *locals;
{
	if (err != E_DONE) {
		err_input(err);
		return NULL;
	}
	return run_node(n, filename, globals, locals);
}

static object *
run_node(n, filename, globals, locals)
	node *n;
	char *filename;
	object *globals, *locals;
{
	return eval_node(n, filename, globals, locals);
}

static object *
eval_node(n, filename, globals, locals)
	node *n;
	char *filename;
	object *globals;
	object *locals;
{
	codeobject *co;
	object *v;
	co = compile(n, filename);
	freetree(n);
	if (co == NULL)
		return NULL;
	v = eval_code(co, globals, locals, (object *)NULL, (object *)NULL);
	DECREF(co);
	return v;
}

object *
compile_string(str, filename, start)
	char *str;
	char *filename;
	int start;
{
	node *n;
	int err;
	codeobject *co;
	err = parse_string(str, start, &n);
	if (err != E_DONE) {
		err_input(err);
		return NULL;
	}
	co = compile(n, filename);
	freetree(n);
	return (object *)co;
}

/* Simplified interface to parsefile */

int
parse_file(fp, filename, start, n_ret)
	FILE *fp;
	char *filename;
	int start;
	node **n_ret;
{
	int ret;
	BGN_SAVE
	ret = parsefile(fp, filename, &gram, start,
				(char *)0, (char *)0, n_ret);
	END_SAVE
	return ret;
}

/* Simplified interface to parsestring */

int
parse_string(str, start, n_ret)
	char *str;
	int start;
	node **n_ret;
{
	int err = parsestring(str, &gram, start, n_ret);
	/* Don't confuse early end of string with early end of input */
	if (err == E_EOF)
		err = E_SYNTAX;
	return err;
}

/* Print fatal error message and abort */

void
fatal(msg)
	char *msg;
{
	fprintf(stderr, "Fatal error: %s\n", msg);
	abort();
}

/* Clean up and exit */

#ifdef USE_THREAD
extern int threads_started;
#endif

static void
cleanup()
{
	object *exitfunc = sysget("exitfunc");

	if (exitfunc) {
		object *arg;
		object *res;
		sysset("exitfunc", (object *)NULL);
		arg = newtupleobject(0);
		if (arg == NULL)
			res = NULL;
		else {
			res = call_object(exitfunc, arg);
			DECREF(arg);
		}
		if (res == NULL) {
			fprintf(stderr, "Error in sys.exitfunc:\n");
			print_error();
		}
	}

	flushline();
}

#ifdef COUNT_ALLOCS
extern void dump_counts PROTO((void));
#endif

void
goaway(sts)
	int sts;
{
	cleanup();

#ifdef COUNT_ALLOCS
	dump_counts();
#endif

#ifdef USE_THREAD

	/* Other threads may still be active, so skip most of the
	   cleanup actions usually done (these are mostly for
	   debugging anyway). */
	
	(void) save_thread();
	donecalls();
	if (threads_started)
		_exit_prog(sts);
	else
		exit_prog(sts);
	
#else /* USE_THREAD */
	
	/* XXX Call doneimport() before donecalls(), since donecalls()
	   calls wdone(), and doneimport() may close windows */
	doneimport();
	donecalls();
	
	err_clear();

#ifdef REF_DEBUG
	fprintf(stderr, "[%ld refs]\n", ref_total);
#endif

#ifdef TRACE_REFS
	if (askyesno("Print left references?")) {
		printrefs(stderr);
	}
#endif /* TRACE_REFS */

	exit(sts);
#endif /* USE_THREAD */
	/*NOTREACHED*/
}

#ifdef HANDLE_SIGNALS
static SIGTYPE
sighandler(sig)
	int sig;
{
	signal(sig, SIG_DFL); /* Don't catch recursive signals */
	cleanup(); /* Do essential clean-up */
	kill(getpid(), sig); /* Pretend the signal killed us */
	/*NOTREACHED*/
}
#endif

static void
initsigs()
{
	initintr();
#ifdef HANDLE_SIGNALS
	if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
		signal(SIGHUP, sighandler);
	if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
		signal(SIGTERM, sighandler);
#endif
}

#ifdef TRACE_REFS
/* Ask a yes/no question */

int
askyesno(prompt)
	char *prompt;
{
	char buf[256];
	
	printf("%s [ny] ", prompt);
	if (fgets(buf, sizeof buf, stdin) == NULL)
		return 0;
	return buf[0] == 'y' || buf[0] == 'Y';
}
#endif

#ifdef applec /* MPW (also usable for Think C 3.0) */

/* Check for file descriptor connected to interactive device.
   Pretend that stdin is always interactive, other files never. */

int
isatty(fd)
	int fd;
{
	return fd == fileno(stdin);
}

#endif