/* Copyright 2009 Myhailo Danylenko

This file is part of lua-lm.

lua-lm 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, see <http://www.gnu.org/licenses/>. */

#include <lua.h>
#include <lauxlib.h>
#include <glib.h>			// GDestroyNotify, GMainContext
#include <loudmouth/loudmouth.h>

#include "config.h"
#include "util.h"
#include "lm_types.h"
#include "lm_message.h"
#include "lm_message_handler.h"

/// lm.connection
/// Central module, representing connection to the server.
/// You should create a new connection object, then open it (establish
/// connection), then authenticate to the server.

/// connection state
/// Stirng, representing current connection state.
/// G:
const string2enum_t state_lm_connection[] = {
	{ "closed",         LM_CONNECTION_STATE_CLOSED         },
	{ "opening",        LM_CONNECTION_STATE_OPENING        },
	{ "open",           LM_CONNECTION_STATE_OPEN           },
	{ "authenticating", LM_CONNECTION_STATE_AUTHENTICATING },
	{ "authenticated",  LM_CONNECTION_STATE_AUTHENTICATED  },
	{ NULL,             0                                  }, // XXX
};

/// handler priority
/// String, according to which handler will be placed into one
/// of three handler groups.
/// G:
const string2enum_t priority_lm_handler[] = {
	{ "last",   LM_HANDLER_PRIORITY_LAST   },
	{ "normal", LM_HANDLER_PRIORITY_NORMAL },
	{ "first",  LM_HANDLER_PRIORITY_FIRST  },
	{ NULL,     0                          }, // XXX
};

/// disconnect reason
/// String, indicating the reason of disconnection occured.
/// G:
static const string2enum_t llm_disconnect_reason[] = {
	{ "ok",                LM_DISCONNECT_REASON_OK                },
	{ "ping time out",     LM_DISCONNECT_REASON_PING_TIME_OUT     },
	{ "hup",               LM_DISCONNECT_REASON_HUP               },
	{ "error",             LM_DISCONNECT_REASON_ERROR             },
	{ "resource conflict", LM_DISCONNECT_REASON_RESOURCE_CONFLICT },
	{ "invalid xml",       LM_DISCONNECT_REASON_INVALID_XML       },
	{ "unknown",           LM_DISCONNECT_REASON_UNKNOWN           },
	{ "ping_time_out",     LM_DISCONNECT_REASON_PING_TIME_OUT     },
	{ "resource_conflict", LM_DISCONNECT_REASON_RESOURCE_CONFLICT },
	{ "invalid_xml",       LM_DISCONNECT_REASON_INVALID_XML       },
	{ NULL,                0                                      }, // XXX
};

/// lm.connection.new
/// Creates a new connection (closed).
/// A: string (server name), lightuserdata (C glib main context object, optional)
/// R: lm connection object
static int new_lm_connection (lua_State *L)
{
	const char *server = luaL_checkstring (L, 1);
	LmConnection *connection;
	if (lua_gettop (L) < 2)
		connection = lm_connection_new (server);
	else {
		luaL_argcheck (L, lua_islightuserdata (L, 2), 2, "glib main context lightuserdata expected");
		connection = lm_connection_new_with_context (server, (GMainContext *) lua_touserdata (L, 2));
	}
	bless_lm_connection (L, connection);
	lm_connection_unref (connection);
	D ("Connection %X created", (int) connection);
	return 1;
}

/// lm.connection.bless
/// Blesses given pointer to lm connection object.
/// Note: it adds a reference to connection.
/// A: lightuserdata (C lm connection object)
/// R: lm connection object
static int bless_lua_lm_connection (lua_State *L)
{
	luaL_argcheck (L, lua_islightuserdata (L, 1), 1, "loudmouth connection lightuserdata expected");
	bless_lm_connection (L, (LmConnection *) lua_touserdata (L, 1));
	return 1;
}

/// connection callback function
/// User function, that will be called on connection establishment operation end,
/// eg. successful/unsuccessful opening or authentication.
/// A: lm connection object, boolean (success)
static void callback_lm_connection (LmConnection *connection, int success, llm_callback_t *cb)
{
	lua_rawgeti (cb->L, LUA_REGISTRYINDEX, cb->reference);
	bless_lm_connection (cb->L, connection);
	// XXX lm_connection_unref (connection);
	lua_pushboolean (cb->L, success);
	if (lua_pcall (cb->L, 2, 0, 0)) {
		W ("Connection callback error: %s", lua_tostring (cb->L, -1));
		lua_pop (cb->L, 1);
	}
}

/// connection:open
/// Opens connection to the server and then calls callback function.
/// A: connection callback function
/// R: lm connection object or nil, string (error message)
static int open_lm_connection (lua_State *L)
{
	llm_connection_t *object = luaL_checklm_connection (L, 1);
	llm_callback_t *cb;
	GError *err = NULL;
	luaL_argcheck (L, lua_isfunction (L, 2), 2, "function expected");
	
	cb = luaL_malloc (L, sizeof (llm_callback_t));
	cb->reference = luaL_ref (L, LUA_REGISTRYINDEX);
	cb->L         = L;

	if (lm_connection_open (object->connection, (LmResultFunction) callback_lm_connection,
				 cb, (GDestroyNotify) llm_callback_destroy, &err))
		return 1;
	else {
		lua_pushnil (L);
		lua_pushstring (L, err->message);
		I ("Connection opening failed: %s", err -> message);
		g_error_free (err);
		return 2;
	}
}

/// connection:authenticate
/// Tries to authenticate against opened connection, then calls callback function.
/// A: string (username), string (password), string (resource), connection callback function
/// R: lm connection object or nil, string (error message)
static int authenticate_lm_connection (lua_State *L)
{
	llm_connection_t *object = luaL_checklm_connection (L, 1);
	const char *username = luaL_checkstring (L, 2);
	const char *password = luaL_checkstring (L, 3);
	const char *resource = luaL_checkstring (L, 4);
	llm_callback_t *cb;
	int status;
	GError *err = NULL;
	luaL_argcheck (L, lua_isfunction (L, 5), 5, "function expected");

	cb = luaL_malloc (L, sizeof (llm_callback_t));
	cb->reference = luaL_ref (L, LUA_REGISTRYINDEX);
	cb->L         = L;

	if (lm_connection_authenticate (object->connection, username, password, resource,
						(LmResultFunction) callback_lm_connection, cb,
						(GDestroyNotify) llm_callback_destroy, &err)) {
		lua_pop (L, 3);
		return 1;
	} else {
		lua_pushnil (L);
		lua_pushstring (L, err->message);
		I ("Connection authentication failed: %s", err->message);
		g_error_free (err);
		return 2;
	}
}

/// connection:port
/// Gets or sets server port to connect.
/// A: integer (optional)
/// R: integer (when called with no args) or lm connection object
static int port_lm_connection (lua_State *L)
{
	llm_connection_t *object = luaL_checklm_connection (L, 1);
	if (lua_gettop (L) > 1) { // Set
		lm_connection_set_port (object->connection, luaL_checkint (L, 2));
		lua_pop (L, 1);
	} else { // Get
		lua_pushnumber (L, lm_connection_get_port (object->connection));
	}
	return 1;
}

/// connection:server
/// Gets or sets server to connect to.
/// A: string (optional, server name)
/// R: string (when called with no args) or lm connection object
static int server_lm_connection (lua_State *L)
{
	llm_connection_t *object = luaL_checklm_connection (L, 1);
	if (lua_gettop (L) > 1) { // Set
		lm_connection_set_server (object->connection, luaL_checkstring (L, 2));
		lua_pop (L, 1);
	} else { // Get
		lua_pushstring (L, lm_connection_get_server (object->connection));
	}
	return 1;
}

/// connection:jid
/// Gets or sets jid for connection.
/// A: string (optional)
/// R: string (when called with no args) or lm connection object
static int jid_lm_connection (lua_State *L)
{
	llm_connection_t *object = luaL_checklm_connection (L, 1);
	if (lua_gettop (L) > 1) { // Set
		lm_connection_set_jid (object->connection, luaL_checkstring (L, 2));
		lua_pop (L, 1);
	} else { // Get
		lua_pushstring (L, lm_connection_get_jid (object->connection));
	}
	return 1;
}

/// connection:keep_alive_rate
/// Gets or sets keep alive packets rate for connection.
/// Note, that on some platforms there is no get function even in
/// loudmouth versions, that should have it according to documentation.
/// integer (optional, seconds)
/// integer (when called with no args) or lm connection object or nil, string (error message, when get function is not available in loudmouth)
static int keep_alive_rate_lm_connection (lua_State *L)
{
	llm_connection_t *object = luaL_checklm_connection (L, 1);
	if (lua_gettop (L) > 1) { // Set
		lm_connection_set_keep_alive_rate (object->connection, luaL_checkint (L, 2));
		lua_pop (L, 1);
		return 1;
	} else { // Get
#ifdef HAVE_LM_CONNECTION_GET_KEEP_ALIVE_RATE
		lua_pushnumber (L, lm_connection_get_keep_alive_rate (object->connection));
		return 1;
#else
		W ("Sorry, your loudmouth have no get_keep_alive_rate ()");
		lua_pushnil (L);
		lua_pushliteral (L, "Sorry, your loudmouth have no get_keep_alive_rate ()");
		return 2;
#endif
	}
}

/// connection:proxy
/// Gets or sets proxy server for connection.
/// A: lm proxy object (optional)
/// R: lm proxy object or nil (when called with no args) or lm connection object
static int proxy_lm_connection (lua_State *L)
{
	llm_connection_t *object = luaL_checklm_connection (L, 1);
	if (lua_gettop (L) > 1) { // Set
		llm_proxy_t *proxy = luaL_checklm_proxy (L, 2);
		lm_connection_set_proxy (object->connection, proxy->proxy);
		lua_pop (L, 1);
	} else { // Get
		LmProxy *proxy = lm_connection_get_proxy (object->connection);
		lua_pop (L, 1);
		if (proxy) {
			bless_lm_proxy (L, proxy);
			// XXX lm_proxy_unref (proxy);
		} else
			lua_pushnil (L);
	}
	return 1;
}

/// connection:ssl
/// Gets or sets ssl object for connection.
/// A: lm ssl object (optional)
/// R: lm ssl object or nil (when called with no args) or lm connection object
static int ssl_lm_connection (lua_State *L)
{
	llm_connection_t *object = luaL_checklm_connection (L, 1);
	if (lua_gettop (L) > 1) { // Set
		llm_ssl_t *ssl = luaL_checklm_ssl (L, 2);
		lm_connection_set_ssl (object->connection, ssl->ssl);
		lua_pop (L, 1);
	} else { // Get
		LmSSL *ssl = lm_connection_get_ssl (object->connection);
		lua_pop (L, 1);
		if (ssl) {
			bless_lm_ssl (L, ssl);
			// XXX lm_ssl_unref (ssl);
		} else
			lua_pushnil (L);
	}
	return 1;
}

/// connection:close
/// Close connection.
/// R: lm connection object or nil, string (error message)
static int close_lm_connection (lua_State *L)
{
	llm_connection_t *object = luaL_checklm_connection (L, 1);
	GError *err = NULL;
	if (lm_connection_close (object->connection, &err))
		return 1;
	else {
		I ("Connection close failed: %s", err->message);
		lua_pushnil (L);
		lua_pushstring (L, err->message);
		g_error_free (err);
		return 2;
	}
}

/// connection:status
/// Returns string, describing connection state.
/// R: connection state
static int status_lm_connection (lua_State *L)
{
	llm_connection_t *connection = luaL_checklm_connection (L, 1);
	luaL_pushenum (L, lm_connection_get_state (connection->connection), state_lm_connection);
	return 1;
}

/// connection:send
/// Sends message. If specified, handler function will be called upon receiving of response to this message.
/// Handler function can be either a message handler object or just a message handler function.
/// Message can be raw xml string. However, you cannot use it with handler function.
/// In short:
/// * connection, errmsg = connection:send ( "raw xml" )
/// * connection, errmsg = connection:send ( message )
/// * connection, errmsg = connection:send ( message, function ( connection, message ) end )
/// * connection, errmsg = connection:send ( message, handler )
/// If connection is nil, errmsg contains error message.
/// A: lm message object/string, message handler callback function/lm message handler object (optional)
/// R: lm connection object or nil, string (error message)
static int send_lm_connection (lua_State *L)
{
	llm_connection_t *object = luaL_checklm_connection (L, 1);
	int status;
	GError *err = NULL;
	if (lua_gettop (L) < 3) { // Send
		if (lua_type (L, 2) == LUA_TSTRING)
			status = lm_connection_send_raw (object->connection, lua_tostring (L, 2), &err);
		else {
			llm_message_t *message = luaL_checklm_message (L, 2);
			status = lm_connection_send (object->connection, message->message, &err);
		}
	} else if (lua_isfunction (L, 3)) { // Send w/reply, func
		llm_message_t    *message = luaL_checklm_message (L, 2);
		llm_callback_t   *cb      = luaL_malloc (L, sizeof (llm_callback_t));
		LmMessageHandler *handler;

		cb->reference = luaL_ref (L, LUA_REGISTRYINDEX);
		cb->L         = L;
		handler = lm_message_handler_new (
					(LmHandleMessageFunction)callback_lm_handler,
					cb, (GDestroyNotify)llm_callback_destroy);
		status = lm_connection_send_with_reply (object->connection,
							message->message, handler, &err);
		lm_message_handler_unref (handler);
	} else { // Send w/reply, handler
		llm_message_t *message = luaL_checklm_message (L, 2);
		llm_handler_t *handler = luaL_checklm_handler (L, 3);
		status = lm_connection_send_with_reply (object->connection, message->message,
							handler->handler, &err);
		lua_pop (L, 1);
	};
	lua_pop (L, 1);
	if (status)
		return 1;
	else {
		I ("Message sending failed: %s", err->message);
		lua_pushnil (L);
		lua_pushstring (L, err->message);
		g_error_free (err);
		return 2;
	}
}

/// connection:handler
/// Registers or unregisters handler function for a given type of messages.
/// To unregister handler, omit the priority argument.
/// To unregister reply handler, omit message type argument too.
/// Handler function can be specified as plain function or message handler object.
/// A: message handler callback function or lm message handler object, message type (optional), handler priority (optional)
/// R: lm connection object
static int handler_lm_connection (lua_State *L)
{
	llm_connection_t *object = luaL_checklm_connection (L, 1);
	int top  = lua_gettop (L);
	if (top > 2) { // Have message type
		int type = luaL_checkenum (L, 3, type_lm_message);

		if (lua_gettop (L) > 3) { // Register
			int priority = luaL_checkenum (L, 4, priority_lm_handler);

			if (lua_isfunction (L, 2)) { // Function
				LmMessageHandler *handler;
				llm_callback_t *cb = luaL_malloc (L, sizeof (llm_callback_t));
				lua_pushvalue (L, 2);
				cb->reference = luaL_ref (L, LUA_REGISTRYINDEX);
				cb->L         = L;

				handler = lm_message_handler_new (
						(LmHandleMessageFunction)callback_lm_handler,
						cb, (GDestroyNotify)llm_callback_destroy);
				lm_connection_register_message_handler (object->connection,
									handler, type, priority);
				lm_message_handler_unref (handler);
			} else { // Object
				llm_handler_t *handler = luaL_checklm_handler (L, 2);
				lm_connection_register_message_handler (object->connection,
									handler->handler,
									type, priority);
			}
			lua_pop (L, 1);
		} else { // Unregister message handler
			llm_handler_t *handler = luaL_checklm_handler (L, 2);
			lm_connection_unregister_message_handler (object->connection,
								  handler->handler,
								  type);
		}
		lua_pop (L, 1);
	} else { // Unregister reply handler
#ifdef HAVE_LM_CONNECTION_UNREGISTER_REPLY_HANDLER
		llm_handler_t *handler = luaL_checklm_handler (L, 2);
		lm_connection_unregister_reply_handler (object -> connection,
		                                        handler -> handler);
#else
		W ("Sorry, your loudmouth have no unregister_reply_handler ()");
		lua_pushnil (L);
		lua_pushliteral (L, "Sorry, your loudmouth have no unregister_reply_handler ()");
		return 2;
#endif
	}
	lua_pop (L, 1);
	return 1;
}

/// disconnect callback function
/// Function, that will be called when disconnection occurs.
/// A: lm connection object, disconnect reason
void llm_disconnect_callback (LmConnection *connection, LmDisconnectReason reason, llm_callback_t *cb)
{
	lua_rawgeti (cb->L, LUA_REGISTRYINDEX, cb->reference);
	bless_lm_connection (cb->L, connection);
	// XXX lm_connection_unref (connection);
	luaL_pushenum (cb->L, reason, llm_disconnect_reason);
	if (lua_pcall (cb->L, 2, 0, 0)) {
		W ("Disconnect callback error: %s", lua_tostring (cb->L, -1));
		lua_pop (cb->L, 1);
	}
}

/// connection:ondisconnect
/// Sets callback, that will be called on connection disconnect.
/// A: disconnect callback function
/// R: lm connection object
static int ondisconnect_lm_connection (lua_State *L)
{
	llm_connection_t *object = luaL_checklm_connection (L, 1);
	llm_callback_t *cb;
	luaL_argcheck (L, lua_isfunction (L, 2), 2, "function expected");

	cb = luaL_malloc (L, sizeof (llm_callback_t));
	cb->reference  = luaL_ref (L, LUA_REGISTRYINDEX);
	cb->L          = L;

	lm_connection_set_disconnect_function (object->connection,
					       (LmDisconnectFunction)llm_disconnect_callback,
					       cb, (GDestroyNotify)llm_callback_destroy);
	return 1;
}

/// connection:open_wait
/// Synchronous open call, that will block until connection will be opened.
/// R: lm connection object or nil, string (error message)
static int open_wait_lm_connection (lua_State *L)
{
	llm_connection_t *object = luaL_checklm_connection (L, 1);
	GError *err = NULL;
	if (lm_connection_open_and_block (object->connection, &err))
		return 1;
	else {
		I ("Synchronous connection opening failed: %s", err->message);
		lua_pushnil (L);
		lua_pushstring (L, err->message);
		g_error_free (err);
		return 2;
	}
}

/// connection:authenticate_wait
/// Synchronous authentication call, that will wait until the end of authentication.
/// A: string (username), string (password), string (resource)
/// R: lm connection object or nil, string (error message)
static int authenticate_wait_lm_connection (lua_State *L)
{
	llm_connection_t *object = luaL_checklm_connection (L, 1);
	const char *username = luaL_checkstring (L, 2);
	const char *password = luaL_checkstring (L, 3);
	const char *resource = luaL_checkstring (L, 4);
	GError *err = NULL;
	if (lm_connection_authenticate_and_block (object->connection, username,
								password, resource, &err))
		return 1;
	else {
		I ("Synchronous authentication failed: %s", err->message);
		lua_pushnil (L);
		lua_pushstring (L, err->message);
		g_error_free (err);
		return 2;
	}
}

/// connection:send_wait
/// Synchronous call, that will send message and wait for reply to it.
/// A: lm message object
/// R: lm message object or nil, string (error message)
static int send_wait_lm_connection (lua_State *L)
{
	llm_connection_t *object = luaL_checklm_connection (L, 1);
	llm_message_t *message = luaL_checklm_message (L, 2);
	GError *err = NULL;
	LmMessage *new = lm_connection_send_with_reply_and_block (object->connection,
									message->message, &err);
	if (!new) {
		I ("Synchronous message sending failed: %s", err->message);
		lua_pushnil (L);
		lua_pushstring (L, err->message);
		g_error_free (err);
		return 2;
	} else {
		bless_lm_message (L, new);
		lm_message_unref (new); // XXX
		return 1;
	}
}

/// connection:pointer
/// Returns pointer to underlying C loudmouth structure.
/// R: lightuserdata
static int pointer_lm_connection (lua_State *L)
{
	llm_connection_t *object = luaL_checklm_connection (L, 1);
	lua_pushlightuserdata (L, object->connection);
	lua_remove (L, -2);
	return 1;
}

static int gc_lm_connection (lua_State *L)
{
	llm_connection_t *object = luaL_checklm_connection (L, 1);
	D ("Connection %X gc called", (int) object);
	lm_connection_unref (object->connection);
	return 0;
}

static const luaL_Reg reg_f_lm_connection[] = {
	{ "new",   new_lm_connection       },
	{ "bless", bless_lua_lm_connection },
	{ NULL,    NULL                    },
};

static const luaL_Reg reg_m_lm_connection[] = {
	{ "open",              open_lm_connection              },
	{ "close",             close_lm_connection             },
	{ "authenticate",      authenticate_lm_connection      },
	{ "status",            status_lm_connection            },
	{ "port",              port_lm_connection              },
	{ "server",            server_lm_connection            },
	{ "jid",               jid_lm_connection               },
	{ "keep_alive_rate",   keep_alive_rate_lm_connection   },
	{ "state",             status_lm_connection            },
	{ "proxy",             proxy_lm_connection             },
	{ "ssl",               ssl_lm_connection               },
	{ "send",              send_lm_connection              },
	{ "handler",           handler_lm_connection           },
	{ "ondisconnect",      ondisconnect_lm_connection      },
	{ "open_wait",         open_wait_lm_connection         },
	{ "authenticate_wait", authenticate_wait_lm_connection },
	{ "send_wait",         send_wait_lm_connection         },
	{ "pointer",           pointer_lm_connection           },
	{ "__gc",              gc_lm_connection                },
	{ NULL,                NULL                            },
};

int luaopen_lm_connection (lua_State *L)
{
	luaL_newmetatable (L, "loudmouth.connection");
	lua_pushvalue (L, -1);
	lua_setfield (L, -2, "__index");
	luaL_register (L, NULL, reg_m_lm_connection);
	lua_pop (L, 1);
	lua_newtable (L); // XXX we can specify here exact amount of fields
	luaL_register (L, NULL, reg_f_lm_connection);
	return 1;
}