/*********************************************************************************************************
* Software License Agreement (BSD License)                                                               *
* Author: Sebastien Decugis <sdecugis@freediameter.net>							 *
*													 *
* Copyright (c) 2013, WIDE Project and NICT								 *
* All rights reserved.											 *
* 													 *
* Redistribution and use of this software in source and binary forms, with or without modification, are  *
* permitted provided that the following conditions are met:						 *
* 													 *
* * Redistributions of source code must retain the above 						 *
*   copyright notice, this list of conditions and the 							 *
*   following disclaimer.										 *
*    													 *
* * Redistributions in binary form must reproduce the above 						 *
*   copyright notice, this list of conditions and the 							 *
*   following disclaimer in the documentation and/or other						 *
*   materials provided with the distribution.								 *
* 													 *
* * Neither the name of the WIDE Project or NICT nor the 						 *
*   names of its contributors may be used to endorse or 						 *
*   promote products derived from this software without 						 *
*   specific prior written permission of WIDE Project and 						 *
*   NICT.												 *
* 													 *
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED *
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A *
* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR *
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* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 	 *
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*********************************************************************************************************/

#include <Python.h>
#include <freeDiameter/extension.h>
#include <unistd.h>

/* wrapper generated by SWIG */
#if PY_VERSION_HEX >= 0x03000000
	extern void PyInit__fDpy(void);
	#define WRAPPER_INIT	PyInit__fDpy()
#else /* PY_VERSION_HEX */
	extern void init_fDpy(void);
	#define WRAPPER_INIT	init_fDpy()
#endif /* PY_VERSION_HEX */
	
/* The string created in the shadow proxy C string file */
extern unsigned char fDpy_py[];
extern unsigned int fDpy_py_len;

/* Run an interactive interpreter in a separate thread */
static pthread_t pyinterp = (pthread_t)NULL;
static void * myinterp (void * arg)
{
	char * dum[3] = { "<dbg_interactive>", arg, NULL };

	TRACE_ENTRY("%p", arg);
	
	fd_log_threadname ( "fDpy" );
	
	CHECK_FCT_DO(fd_core_waitstartcomplete(), goto end);
	
	if (arg) {
		fd_log_debug("Starting python interpreter with a script file [experimental].");
		Py_Main(2, dum);
	} else {
		if (!isatty(fileno(stdin)) || !isatty(fileno(stdout))) {
			TRACE_ERROR("[dbg_interactive]: this extension requires freeDiameter to be run from a console terminal!");
			goto end;
		}
		printf("Starting interactive python interpreter [experimental].\n");
		printf("Please use Ctrl-D to exit.\n");
		printf("Example syntax:\n");
		printf("   >>> print cvar.fd_g_config.cnf_diamid\n");
		printf("   '%s'\n", fd_g_config->cnf_diamid);
		Py_Main(1, dum);
		printf("Python interpreter has exited...\n");
	}
	
end:	
	/* Upon exit, issue the order of terminating to fD, if the interpreter was started without a file */
	if (!arg) {
		(void)fd_core_shutdown();
	}

	return NULL;
}

/* Register the callbacks to the daemon */
static int di_main(char * conffile)
{
	char * shadow_hlp = NULL;
	int mustfree = 0;
	TRACE_ENTRY("%p", conffile);
	
	Py_InitializeEx(0);
	
	WRAPPER_INIT;
	
	/* Small hack to avoid duplicating the string, we replace the last char by a \0.
	  It works if the python file is terminated with several \n */
	if (   (fDpy_py[fDpy_py_len - 2] == '\n')
	    && (fDpy_py[fDpy_py_len - 1] == '\n')) {
		fDpy_py[fDpy_py_len - 1] = '\0';
		shadow_hlp = (char *)&fDpy_py[0];
	} else {
		CHECK_MALLOC(shadow_hlp = malloc(fDpy_py_len + 1));
		memcpy(shadow_hlp, fDpy_py, fDpy_py_len);
		shadow_hlp[fDpy_py_len] = '\0';
		mustfree=1;
	}
	
	PyRun_SimpleString("__file__ = \"\"\n");
	PyRun_SimpleString(shadow_hlp);
	
	if (mustfree)
		free(shadow_hlp);
		
	CHECK_POSIX( pthread_create(&pyinterp, NULL, myinterp, conffile) );
 
	return 0;
}

/* Terminate the extension */
void fd_ext_fini(void)
{
	TRACE_ENTRY();
	void * ret;
	
	/* Cleanup the python interpreter */
	Py_Finalize();
	pthread_join(pyinterp, &ret);
	
	return ;
}

/* Define the entry point function */
EXTENSION_ENTRY("dbg_interactive", di_main);