/*
* Copyright (c) 2002-2003  Gustavo Niemeyer <niemeyer@conectiva.com>
*
* XChat Python Plugin Interface
*
* Xchat Python Plugin Interface 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.
*
* pybot 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 file; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

/* Thread support
 * ==============
 *
 * The python interpreter has a global interpreter lock. Any thread
 * executing must acquire it before working with data accessible from
 * python code. Here we must also care about xchat not being
 * thread-safe. We do this by using an xchat lock, which protects
 * xchat instructions from being executed out of time (when this
 * plugin is not "active").
 *
 * When xchat calls python code:
 *   - Change the current_plugin for the executing plugin;
 *   - Release xchat lock
 *   - Acquire the global interpreter lock
 *   - Make the python call
 *   - Release the global interpreter lock
 *   - Acquire xchat lock
 *
 * When python code calls xchat:
 *   - Release the global interpreter lock
 *   - Acquire xchat lock
 *   - Restore context, if necessary
 *   - Make the xchat call
 *   - Release xchat lock
 *   - Acquire the global interpreter lock
 *
 * Inside a timer, so that individual threads have a chance to run:
 *   - Release xchat lock
 *   - Go ahead threads. Have a nice time!
 *   - Acquire xchat lock
 *
 */

#include <glib.h>
#include <string.h>
#include <stdlib.h>
#include <sys/types.h>

#ifdef WIN32
#include "../../src/dirent/dirent-win32.h"
#include "../../config-win32.h"
#else
#include <unistd.h>
#include <dirent.h>
#endif

#include "hexchat-plugin.h"
#include "Python.h"
#include "structmember.h"
#include "pythread.h"

#define VERSION_MAJOR 0
#define VERSION_MINOR 9

#ifdef WIN32
#undef WITH_THREAD /* Thread support locks up xchat on Win32. */
#define VERSION "0.9/2.7"	/* Linked to python27.dll */
#else
#define VERSION "0.9"
#endif

#define NONE 0
#define ALLOW_THREADS 1
#define RESTORE_CONTEXT 2

#ifdef WITH_THREAD
#define ACQUIRE_XCHAT_LOCK() PyThread_acquire_lock(xchat_lock, 1)
#define RELEASE_XCHAT_LOCK() PyThread_release_lock(xchat_lock)
#define BEGIN_XCHAT_CALLS(x) \
	do { \
		PyObject *calls_plugin = NULL; \
		PyThreadState *calls_thread; \
		if ((x) & RESTORE_CONTEXT) \
			calls_plugin = Plugin_GetCurrent(); \
		calls_thread = PyEval_SaveThread(); \
		ACQUIRE_XCHAT_LOCK(); \
		if (!((x) & ALLOW_THREADS)) { \
			PyEval_RestoreThread(calls_thread); \
			calls_thread = NULL; \
		} \
		if (calls_plugin) \
			xchat_set_context(ph, \
				Plugin_GetContext(calls_plugin)); \
		while (0)
#define END_XCHAT_CALLS() \
		RELEASE_XCHAT_LOCK(); \
		if (calls_thread) \
			PyEval_RestoreThread(calls_thread); \
	} while(0)
#else
#define ACQUIRE_XCHAT_LOCK()
#define RELEASE_XCHAT_LOCK()
#define BEGIN_XCHAT_CALLS(x)
#define END_XCHAT_CALLS()
#endif

#ifdef WITH_THREAD

#define BEGIN_PLUGIN(plg) \
	do { \
	xchat_context *begin_plugin_ctx = xchat_get_context(ph); \
	RELEASE_XCHAT_LOCK(); \
	Plugin_AcquireThread(plg); \
	Plugin_SetContext(plg, begin_plugin_ctx); \
	} while (0)
#define END_PLUGIN(plg) \
	do { \
	Plugin_ReleaseThread(plg); \
	ACQUIRE_XCHAT_LOCK(); \
	} while (0)

#else /* !WITH_THREAD (win32) */

static PyThreadState *pTempThread;

#define BEGIN_PLUGIN(plg) \
	do { \
	xchat_context *begin_plugin_ctx = xchat_get_context(ph); \
	RELEASE_XCHAT_LOCK(); \
	PyEval_AcquireLock(); \
	pTempThread = PyThreadState_Swap(((PluginObject *)(plg))->tstate); \
	Plugin_SetContext(plg, begin_plugin_ctx); \
	} while (0)
#define END_PLUGIN(plg) \
	do { \
	((PluginObject *)(plg))->tstate = PyThreadState_Swap(pTempThread); \
	PyEval_ReleaseLock(); \
	ACQUIRE_XCHAT_LOCK(); \
	} while (0)

#endif /* !WITH_THREAD */

#define Plugin_Swap(x) \
	PyThreadState_Swap(((PluginObject *)(x))->tstate)
#define Plugin_AcquireThread(x) \
	PyEval_AcquireThread(((PluginObject *)(x))->tstate)
#define Plugin_ReleaseThread(x) \
	Util_ReleaseThread(((PluginObject *)(x))->tstate)
#define Plugin_GetFilename(x) \
	(((PluginObject *)(x))->filename)
#define Plugin_GetName(x) \
	(((PluginObject *)(x))->name)
#define Plugin_GetVersion(x) \
	(((PluginObject *)(x))->version)
#define Plugin_GetDesc(x) \
	(((PluginObject *)(x))->description)
#define Plugin_GetHooks(x) \
	(((PluginObject *)(x))->hooks)
#define Plugin_GetContext(x) \
	(((PluginObject *)(x))->context)
#define Plugin_SetFilename(x, y) \
	((PluginObject *)(x))->filename = (y);
#define Plugin_SetName(x, y) \
	((PluginObject *)(x))->name = (y);
#define Plugin_SetVersion(x, y) \
	((PluginObject *)(x))->version = (y);
#define Plugin_SetDescription(x, y) \
	((PluginObject *)(x))->description = (y);
#define Plugin_SetHooks(x, y) \
	((PluginObject *)(x))->hooks = (y);
#define Plugin_SetContext(x, y) \
	((PluginObject *)(x))->context = (y);

#define HOOK_XCHAT  1
#define HOOK_UNLOAD 2

/* ===================================================================== */
/* Object definitions */

typedef struct {
	PyObject_HEAD
	int softspace; /* We need it for print support. */
} XChatOutObject;

typedef struct {
	PyObject_HEAD
	xchat_context *context;
} ContextObject;

typedef struct {
	PyObject_HEAD
	const char *listname;
	PyObject *dict;
} ListItemObject;

typedef struct {
	PyObject_HEAD
	char *name;
	char *version;
	char *filename;
	char *description;
	GSList *hooks;
	PyThreadState *tstate;
	xchat_context *context;
	void *gui;
} PluginObject;

typedef struct {
	int type;
	PyObject *plugin;
	PyObject *callback;
	PyObject *userdata;
	void *data; /* A handle, when type == HOOK_XCHAT */
} Hook;


/* ===================================================================== */
/* Function declarations */

static PyObject *Util_BuildList(char *word[]);
static void Util_Autoload();
static char *Util_Expand(char *filename);

static int Callback_Command(char *word[], char *word_eol[], void *userdata);
static int Callback_Print(char *word[], void *userdata);
static int Callback_Timer(void *userdata);
static int Callback_ThreadTimer(void *userdata);

static PyObject *XChatOut_New();
static PyObject *XChatOut_write(PyObject *self, PyObject *args);
static void XChatOut_dealloc(PyObject *self);

static void Context_dealloc(PyObject *self);
static PyObject *Context_set(ContextObject *self, PyObject *args);
static PyObject *Context_command(ContextObject *self, PyObject *args);
static PyObject *Context_prnt(ContextObject *self, PyObject *args);
static PyObject *Context_get_info(ContextObject *self, PyObject *args);
static PyObject *Context_get_list(ContextObject *self, PyObject *args);
static PyObject *Context_compare(ContextObject *a, ContextObject *b, int op);
static PyObject *Context_FromContext(xchat_context *context);
static PyObject *Context_FromServerAndChannel(char *server, char *channel);

static PyObject *Plugin_New(char *filename, PyMethodDef *xchat_methods,
			    PyObject *xcoobj);
static PyObject *Plugin_GetCurrent();
static PluginObject *Plugin_ByString(char *str);
static Hook *Plugin_AddHook(int type, PyObject *plugin, PyObject *callback,
			    PyObject *userdata, void *data);
static void Plugin_RemoveHook(PyObject *plugin, Hook *hook);
static void Plugin_RemoveAllHooks(PyObject *plugin);

static PyObject *Module_xchat_command(PyObject *self, PyObject *args);
static PyObject *Module_xchat_prnt(PyObject *self, PyObject *args);
static PyObject *Module_xchat_get_context(PyObject *self, PyObject *args);
static PyObject *Module_xchat_find_context(PyObject *self, PyObject *args,
					   PyObject *kwargs);
static PyObject *Module_xchat_get_info(PyObject *self, PyObject *args);
static PyObject *Module_xchat_hook_command(PyObject *self, PyObject *args,
					   PyObject *kwargs);
static PyObject *Module_xchat_hook_server(PyObject *self, PyObject *args,
					  PyObject *kwargs);
static PyObject *Module_xchat_hook_print(PyObject *self, PyObject *args,
					 PyObject *kwargs);
static PyObject *Module_xchat_hook_timer(PyObject *self, PyObject *args,
					 PyObject *kwargs);
static PyObject *Module_xchat_unhook(PyObject *self, PyObject *args);
static PyObject *Module_xchat_get_info(PyObject *self, PyObject *args);
static PyObject *Module_xchat_get_list(PyObject *self, PyObject *args);
static PyObject *Module_xchat_get_lists(PyObject *self, PyObject *args);
static PyObject *Module_xchat_nickcmp(PyObject *self, PyObject *args);
static PyObject *Module_xchat_strip(PyObject *self, PyObject *args);
static PyObject *Module_xchat_pluginpref_set(PyObject *self, PyObject *args);
static PyObject *Module_xchat_pluginpref_get(PyObject *self, PyObject *args);
static PyObject *Module_xchat_pluginpref_delete(PyObject *self, PyObject *args);
static PyObject *Module_xchat_pluginpref_list(PyObject *self, PyObject *args);

static void IInterp_Exec(char *command);
static int IInterp_Cmd(char *word[], char *word_eol[], void *userdata);

static void Command_PyList();
static void Command_PyLoad(char *filename);
static void Command_PyUnload(char *name);
static void Command_PyReload(char *name);
static void Command_PyAbout();
static int Command_Py(char *word[], char *word_eol[], void *userdata);

/* ===================================================================== */
/* Static declarations and definitions */

staticforward PyTypeObject Plugin_Type;
staticforward PyTypeObject XChatOut_Type;
staticforward PyTypeObject Context_Type;
staticforward PyTypeObject ListItem_Type;

static PyThreadState *main_tstate = NULL;
static void *thread_timer = NULL;

static xchat_plugin *ph;
static GSList *plugin_list = NULL;

static PyObject *interp_plugin = NULL;
static PyObject *xchatout = NULL;

#ifdef WITH_THREAD
static PyThread_type_lock xchat_lock = NULL;
#endif

static const char usage[] = "\
Usage: /PY LOAD   <filename>\n\
           UNLOAD <filename|name>\n\
           RELOAD <filename|name>\n\
           LIST\n\
           EXEC <command>\n\
           CONSOLE\n\
           ABOUT\n\
\n";

static const char about[] = "\
\n\
X-Chat Python Interface " VERSION "\n\
\n\
Copyright (c) 2002-2003  Gustavo Niemeyer <niemeyer@conectiva.com>\n\
\n";


/* ===================================================================== */
/* Utility functions */

static PyObject *
Uti