/* 
 *
 * ***** BEGIN GPL/BL DUAL LICENSE BLOCK *****
 *
 * 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. The Blender
 * Foundation also sells licenses for use in proprietary software under
 * the Blender License.  See http://www.blender.org/BL/ for information
 * about this.
 *
 * 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 the Free Software Foundation,
 * Inc., 59 Temple Place - Suite 330, Boston, MA	02111-1307, USA.
 *
 * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
 * All rights reserved.
 *
 * This is a new part of Blender.
 *
 * Contributor(s): Willian P. Germano
 *
 * ***** END GPL/BL DUAL LICENSE BLOCK *****
*/

#include <BKE_utildefines.h>
#include <BLI_blenlib.h>
#include <PIL_time.h>
#include <Python.h>
#include <sys/stat.h>
#include "gen_utils.h"
#include "modules.h"

/*****************************************************************************/
/* Python API function prototypes for the sys module.                        */
/*****************************************************************************/
static PyObject *M_sys_basename (PyObject *self, PyObject *args);
static PyObject *M_sys_dirname (PyObject *self, PyObject *args);
static PyObject *M_sys_join (PyObject *self, PyObject *args);
static PyObject *M_sys_splitext (PyObject *self, PyObject *args);
static PyObject *M_sys_makename (PyObject *self, PyObject *args, PyObject *kw);
static PyObject *M_sys_exists (PyObject *self, PyObject *args);
static PyObject *M_sys_time (PyObject *self);
static PyObject *M_sys_sleep (PyObject *self, PyObject *args);

/*****************************************************************************/
/* The following string definitions are used for documentation strings.      */
/* In Python these will be written to the console when doing a               */
/* Blender.sys.__doc__                                                       */
/*****************************************************************************/
static char M_sys_doc[] =
"The Blender.sys submodule\n\
\n\
This is a minimal system module to supply simple functionality available\n\
in the default Python module os.";

static char M_sys_basename_doc[] =
"(path) - Split 'path' in dir and filename.\n\
Return the filename.";

static char M_sys_dirname_doc[] =
"(path) - Split 'path' in dir and filename.\n\
Return the dir.";

static char M_sys_join_doc[] =
"(dir, file) - Join dir and file to form a full filename.\n\
Return the filename.";

static char M_sys_splitext_doc[] =
"(path) - Split 'path' in root and extension:\n\
/this/that/file.ext -> ('/this/that/file','.ext').\n\
Return the pair (root, extension).";

static char M_sys_makename_doc[] =
"(path = Blender.Get('filename'), ext = \"\", strip = 0) -\n\
Strip dir and extension from path, leaving only a name, then append 'ext'\n\
to it (if given) and return the resulting string.\n\n\
(path) - string: a pathname -- Blender.Get('filename') if 'path' isn't given;\n\
(ext = \"\") - string: the extension to append.\n\
(strip = 0) - int: strip dirname from 'path' if given and non-zero.\n\
Ex: makename('/path/to/file/myfile.foo','-01.abc') returns 'myfile-01.abc'\n\
Ex: makename(ext='.txt') returns 'untitled.txt' if Blender.Get('filename')\n\
returns a path to the file 'untitled.blend'";

static char M_sys_time_doc[] =
"() - Return a float representing time elapsed in seconds.\n\
Each successive call is garanteed to return values greater than or\n\
equal to the previous call.";

static char M_sys_sleep_doc[] =
"(milliseconds = 10) - Sleep for the specified time.\n\
(milliseconds = 10) - the amount of time in milliseconds to sleep.\n\
This function can be necessary in tight 'get event' loops.";

static char M_sys_exists_doc[] =
"(path) - Check if the given pathname exists.\n\
The return value is as follows:\n\
\t 0: path doesn't exist;\n\
\t 1: path is an existing filename;\n\
\t 2: path is an existing dirname;\n\
\t-1: path exists but is neither a regular file nor a dir.";

/*****************************************************************************/
/* Python method structure definition for Blender.sys module:                */
/*****************************************************************************/
struct PyMethodDef M_sys_methods[] = {
  {"basename",    M_sys_basename,        METH_VARARGS, M_sys_basename_doc},
  {"dirname",     M_sys_dirname,         METH_VARARGS, M_sys_dirname_doc},
  {"join",        M_sys_join,            METH_VARARGS, M_sys_join_doc},
  {"splitext",    M_sys_splitext,        METH_VARARGS, M_sys_splitext_doc},
  {"makename", (PyCFunction)M_sys_makename, METH_VARARGS|METH_KEYWORDS,
		M_sys_makename_doc},
  {"exists",      M_sys_exists,          METH_VARARGS, M_sys_exists_doc},
  {"sleep",      M_sys_sleep,            METH_VARARGS, M_sys_sleep_doc},
  {"time", (PyCFunction)M_sys_time,      METH_NOARGS,  M_sys_time_doc},
  {NULL, NULL, 0, NULL}
};

/* Module Functions */

static PyObject *g_sysmodule = NULL; /* pointer to Blender.sys module */

PyObject *sys_Init (void)
{
	PyObject	*submodule, *dict, *sep;

	submodule = Py_InitModule3("Blender.sys", M_sys_methods, M_sys_doc);

	g_sysmodule = submodule;

	dict = PyModule_GetDict(submodule);

#ifdef WIN32
	sep = Py_BuildValue("s", "\\");
#else
	sep = Py_BuildValue("s", "/");
#endif

	if (sep) {
		Py_INCREF(sep);
		PyDict_SetItemString(dict, "dirsep" , sep);
		PyDict_SetItemString(dict, "sep" , sep);
	}

	return submodule;
}

static PyObject *M_sys_basename (PyObject *self, PyObject *args)
{
	PyObject *c;

	char *name, *p, basename[FILE_MAXFILE];
	char sep;
	int n, len;

	if (!PyArg_ParseTuple(args, "s", &name))
		return EXPP_ReturnPyObjError (PyExc_TypeError,
							"expected string argument");

	len = strlen(name);

	c = PyObject_GetAttrString (g_sysmodule, "dirsep");
	sep = PyString_AsString(c)[0];
	Py_DECREF(c);

	p = strrchr(name, sep);

	if (p) {
		n = name + len - p - 1; /* - 1 because we don't want the sep */

		if (n > FILE_MAXFILE)
			return EXPP_ReturnPyObjError(PyExc_RuntimeError, "path too long");

		BLI_strncpy(basename, p + 1, n + 1);
		return Py_BuildValue("s", basename);
	}

	return Py_BuildValue("s", name);
}

static PyObject *M_sys_dirname (PyObject *self, PyObject *args)
{
	PyObject *c;

	char *name, *p, dirname[FILE_MAXDIR];
	char sep;
	int n;

	if (!PyArg_ParseTuple(args, "s", &name))
		return EXPP_ReturnPyObjError (PyExc_TypeError,
							"expected string argument");

	c = PyObject_GetAttrString (g_sysmodule, "dirsep");
	sep = PyString_AsString(c)[0];
	Py_DECREF(c);

	p = strrchr(name, sep);

	if (p) {
		n = p - name;

		if (n > FILE_MAXDIR)
			return EXPP_ReturnPyObjError (PyExc_RuntimeError, "path too long");

		BLI_strncpy(dirname, name, n + 1);
		return Py_BuildValue("s", dirname);
	}

	return Py_BuildValue("s", ".");
}

static PyObject *M_sys_join (PyObject *self, PyObject *args)
{
	PyObject *c = NULL;
	char *name = NULL, *path = NULL;
	char filename[FILE_MAXDIR+FILE_MAXFILE];
	char sep;
	int pathlen = 0, namelen = 0;

	if (!PyArg_ParseTuple(args, "ss", &path, &name))
		return EXPP_ReturnPyObjError (PyExc_TypeError,
							"expected string argument");

	pathlen = strlen(path) + 1;
	namelen = strlen(name) + 1; /* + 1 to account for '\0' for BLI_strncpy */

	if (pathlen + namelen > FILE_MAXDIR+FILE_MAXFILE - 1)
		return EXPP_ReturnPyObjError (PyExc_RuntimeError, "filename is too long.");

	c = PyObject_GetAttrString (g_sysmodule, "dirsep");
	sep = PyString_AsString(c)[0];
	Py_DECREF(c);
	
	BLI_strncpy(filename, path, pathlen);

	if (filename[pathlen - 2] != sep) {
		filename[pathlen - 1] = sep;
		pathlen += 1;
	}

	BLI_strncpy(filename + pathlen - 1, name, namelen);

	return Py_BuildValue("s", filename);
}

static PyObject *M_sys_splitext (PyObject *self, PyObject *args)
{
	PyObject *c;

	char *name, *dot, *p, path[FILE_MAXFILE], ext[FILE_MAXFILE];
	char sep;
	int n, len;

	if (!PyArg_ParseTuple(args, "s", &name))
		return EXPP_ReturnPyObjError (PyExc_TypeError,
							"expected string argument");

	len = strlen(name);

	c = PyObject_GetAttrString (g_sysmodule, "dirsep");
	sep = PyString_AsString(c)[0];
	Py_DECREF(c);

	dot = strrchr(name, '.');

	if (!dot) return Py_BuildValue("ss", name, "");

	p = strrchr(name, sep);

	if (p) {
		if (p > dot) return Py_BuildValue("ss", name, "");
	}

	n = name + len - dot;

	/* loong extensions are supported -- foolish, but Python's os.path.splitext
	 * supports them, so ... */
	if (n > FILE_MAXFILE || (len - n ) > FILE_MAXFILE)
		EXPP_ReturnPyObjError(PyExc_RuntimeError, "path too long");

	BLI_strncpy(ext, dot, n + 1);
	BLI_strncpy(path, name, dot - name + 1);

	return Py_BuildValue("ss", path, ext);
}

static PyObject *M_sys_makename(PyObject *self, PyObject *args, PyObject *kw)
{
	char *path = G.sce, *ext = NULL;
	int strip = 0;
	static char *kwlist[] = {"path", "ext", "strip", NULL};
	char *dot = NULL, *p = NULL, basename[FILE_MAXFILE];
	char sep;
	int n, len, lenext = 0;
	PyObject *c;

	if (!PyArg_ParseTupleAndKeywords(args, kw, "|ssi", kwlist,
			&path, &ext, &strip))
		return EXPP_ReturnPyObjError (PyExc_TypeError,
			"expected one or two strings and an int (or nothing) as arguments");

	len = strlen(path) + 1; /* + 1 to consider ending '\0' */
	if (ext) lenext = strlen(ext) + 1;

	if ((len + lenext) > FILE_MAXFILE)
		return EXPP_ReturnPyObjError(PyExc_RuntimeError, "path too long");

	c = PyObject_GetAttrString (g_sysmodule, "dirsep");
	sep = PyString_AsString(c)[0];
	Py_DECREF(c);

	p = strrchr(path, sep);

	if (p && strip) {
		n = path + len - p;
		BLI_strncpy(basename, p + 1, n); /* + 1 to skip the sep */
	}
	else
		BLI_strncpy(basename, path, len);

	dot = strrchr(basename, '.');

	/* now the extension: always remove the one in basename */
	if (dot || ext) {
		if (!ext)
			basename[dot - basename] = '\0';
		else { /* if user gave an ext, append it */

			if (dot) n = dot - basename;
			else n = strlen(basename);

			BLI_strncpy(basename + n, ext, lenext);
		}
	}

	return PyString_FromString(basename);
}

static PyObject *M_sys_time (PyObject *self)
{
	double t = PIL_check_seconds_timer();
	return Py_BuildValue("d", t);
}

static PyObject *M_sys_sleep (PyObject *self, PyObject *args)
{
	int millisecs = 10;

	if (!PyArg_ParseTuple(args, "|i", &millisecs))
		return EXPP_ReturnPyObjError (PyExc_TypeError,
							"expected int argument");

	PIL_sleep_ms(millisecs);

	return EXPP_incr_ret(Py_None);
}

static PyObject *M_sys_exists (PyObject *self, PyObject *args)
{
	struct stat st;
	char *fname = NULL;
	int res = 0, i = -1;

	if (!PyArg_ParseTuple(args, "s", &fname))
		return EXPP_ReturnPyObjError (PyExc_TypeError,
							"expected string (pathname) argument");

	res = stat(fname, &st);

	if (res == -1) i = 0;
	else if (S_ISREG(st.st_mode)) i = 1;
	else if (S_ISDIR(st.st_mode)) i = 2;
	/* i stays as -1 if path exists but is neither a regular file nor a dir */

	return Py_BuildValue("i", i);
}
