/*
   core/application.cc
   This file is part of the Osirion project and is distributed under
   the terms of the GNU General Public License version 2
*/

#include <errno.h>
#include <signal.h>

#include <iostream>
#include <vector>
#include <sstream>
#include <fstream>

#include "auxiliary/functions.h"
#include "sys/sys.h"
#include "math/mathlib.h"
#include "filesystem/filesystem.h"
#include "core/application.h"
#include "core/core.h"
#include "core/cvar.h"
#include "core/entity.h"
#include "core/func.h"
#include "core/gameconnection.h"
#include "core/gameserver.h"
#include "core/loader.h"

namespace core
{

/* ---- signal handler --------------------------------------------- */

#ifndef _WIN32
extern "C" void signal_handler(int signum)
{
	switch (signum) {
		case SIGHUP:
		case SIGINT:
		case SIGQUIT:
		case SIGTERM:
			if (Application::instance()) {
				con_warn << "Received signal " << signum << ", shutting down...\n";
				Application::instance()->shutdown();
				Application::instance()->quit(0);
			} else {
				std::cerr << "Received signal " << signum << ", terminated...\n";
				Application::instance()->quit(1);
			}
			break;
#ifdef HAVE_CURSES
		case SIGWINCH:
			sys::ConsoleInterface::instance()->resize();
			break;
#endif
		default:
			std::cerr << "Received signal " << signum << ", terminated...\n";
			Application::instance()->quit(1);
			break;
	}
}
#endif

/* ---- class Application ------------------------------------------ */

Application *Application::application_instance = 0;

Application::Application()
{
	if (application_instance) {
		std::cerr << "multiple core::Application instances\n";
		sys::quit(2);
	}

	application_instance = this;
	application_game = 0;

#ifndef _WIN32
	sys::signal(SIGHUP, signal_handler);
	sys::signal(SIGINT, signal_handler);
	sys::signal(SIGQUIT, signal_handler);
	sys::signal(SIGTERM, signal_handler);
#ifdef HAVE_CURSES
	sys::signal(SIGWINCH, signal_handler);
#endif
#endif

}

Application::~Application()
{
	application_instance = 0;
}

void Application::init(int count, char **arguments)
{
	con_print << "^BInitializing core...\n";
	con_debug << "  debug messages enabled\n";

	filesystem::init(arguments[0], "base", "");
	Loader::load("base");

	CommandBuffer::init();

	// dedicated server has set this to 1
	Cvar::sv_dedicated = Cvar::get("sv_dedicated", "0", Cvar::ReadOnly);
	Cvar::sv_dedicated->set_info("[bool] indicates this is a dedicated server");

	// client can set this to 1
	Cvar::sv_private = Cvar::get("sv_private", "0");
	Cvar::sv_private->set_info("[bool] enable or disable network server for a client");

	// load configuration
	load_config();
	load_autoexec();

	// load command line
	load_commandline(count, arguments);

	// framerate settings
	Cvar::sv_framerate = Cvar::get("sv_framerate", "25");
	Cvar::sv_framerate->set_info("[int] server framerate in frames/sec");

	// server settings
	Cvar::sv_name = Cvar::get("sv_name", "osirion server", Cvar::Archive);
	Cvar::sv_name->set_info("[string] server name");

	Cvar::sv_description = Cvar::get("sv_description", "default server", Cvar::Archive);
	Cvar::sv_description->set_info("[string] server description");

	Cvar::sv_password = Cvar::get("sv_password", "", Cvar::Archive);
	Cvar::sv_password->set_info("[string] server rcon password");
	
	Cvar::sv_keepalive = Cvar::get("sv_keepalive", "120", core::Cvar::Archive);
	Cvar::sv_keepalive->set_info("[int] number of seconds to keep dynamic objects alive");
	
	Cvar::sv_collisionmargin = Cvar::get("sv_collisionmargin", 1.0f / 64.0f, core::Cvar::Archive);
	Cvar::sv_collisionmargin->set_info("[float] margin for mesh collisions");

	// network settings
	Cvar::net_host = Cvar::get("net_host", "0.0.0.0", Cvar::Archive);
	Cvar::net_host->set_info("[address] IP address the network server binds to");

	Cvar::net_port = Cvar::get("net_port", "8042", Cvar::Archive);
	Cvar::net_port->set_info("[int] default network port");

	Cvar::net_maxclients = Cvar::get("net_maxclients", "16", Cvar::Archive);
	Cvar::net_maxclients->set_info("[int] maximum number of network clients");

	Cvar::net_timeout = Cvar::get("net_timeout", "20");
	Cvar::net_timeout->set_info("[int] network timeout in seconds");

	Cvar::net_framerate = Cvar::get("net_framerate", "25");
	Cvar::net_framerate->set_info("[int] network framerate in frames/sec");
	
	Cvar::net_selecttimeout = Cvar::get("net_selecttimeout", "10000");
	Cvar::net_framerate->set_info("[int] network select() call timeout, in microseconds");
	
	Cvar::mem_vertex = core::Cvar::get("mem_vertex", "64" , core::Cvar::Archive);
	Cvar::mem_vertex->set_info("[int] amount of video memory reserved for model geometry, in megabytes");

#ifdef _WIN32
	Cvar::con_ansi = Cvar::get("con_ansi", "0", Cvar::Archive);
#else
	Cvar::con_ansi = Cvar::get("con_ansi", "1", Cvar::Archive);
#endif
	Cvar::con_ansi->set_info("[bool] console ANSI colors");
	sys::set_ansi(Cvar::con_ansi->value());

	if (Cvar::sv_dedicated->value()) {
		Cvar::con_timestamps = Cvar::get("con_timestamps", "1", Cvar::Archive);
	} else {
		Cvar::con_timestamps = Cvar::get("con_timestamps", "0", Cvar::Archive);
	}
	Cvar::con_timestamps->set_info("[bool] enable console timestamps");
	sys::set_console_timestamps(Cvar::con_timestamps->value());
	
#ifdef _WIN32
	// Initialize win32 socket library
	WSADATA wsa_data;
	WORD wsa_version = MAKEWORD(2, 0);
	if (WSAStartup(wsa_version, &wsa_data) != 0) {
		con_warn << "Could not initialize socket library!" << std::endl;
	}
#endif

	// register our engine functions
	Func *func = 0;

	func = Func::add("help", Application::func_help);
	func->set_info("help function");

	func = Func::add("quit", Application::func_quit);
	func->set_info("exit the application");

	func = Func::add("load", Application::func_load);
	func->set_info("[string] load a game module");

	func = Func::add("connect", Application::func_connect);
	func->set_info("[ip] without ip, create a game");

	func = Func::add("disconnect", Application::func_disconnect);
	func->set_info("leave the current game");

	func = Func::add("shout", Application::func_shout);
	func->set_info("shout [text] shout something on the global chat");
	
	func = Func::add("say", Application::func_say);
	func->set_info("say [text] say something on the local chat");

	func = Func::add("msg", Application::func_msg);
	func->set_info("msg [player] [text] send a private message to another player");

	func = Func::add("rcon", Application::func_rcon);
	func->set_info("[string] send a console command to the server");

	func = 0;
}

void Application::shutdown()
{
	con_print << "^BShutting down core...\n";

	if (connected())
		disconnect();

	if (application_game) {
		delete application_game;
		application_game = 0;
	}

	save_config();

	Loader::clear();

	// remove our engine functions
	Func::remove("msg");
	Func::remove("say");
	Func::remove("help");
	Func::remove("quit");

	Func::remove("connect");
	Func::remove("disconnect");
	Func::remove("load");

#ifdef _WIN32
	// shutdown win32 socket library
	WSACleanup();
#endif

	CommandBuffer::shutdown();

	filesystem::shutdown();
}

void Application::quit(int status)
{
	sys::quit(status);
}


bool Application::load(std::string const &label)
{
	if (!label.size()) {
		Loader::list();
		return false;
	}

	if (connected() && game()->interactive()) {
		con_warn << "Connected. Disconnect first.\n";
		return false;
	}

	if (!Loader::load(label)) {
		return false;
	}

	return true;
}

void Application::connect(std::string const &host)
{
	if (connected() && game()->interactive()) {
		con_warn << "Connected. Disconnect first.\n";
		return;
	}

	if (application_game) {
		disconnect();
	}

	if (host.size()) {
		notify_connect();
		application_game = new GameConnection(host);

		if (!application_game->running()) {
			delete application_game;
			application_game = 0;
		}
	} else {
		notify_connect();
		application_game = new GameServer();

		if (application_game->running()) {
			con_print << "^BConnected to local game.\n";
		} else {
			delete application_game;
			application_game = 0;
			con_warn << "Could not connect to local game!\n";
		}
	}
}

void Application::disconnect()
{
	if (application_game) {
		delete application_game;
		application_game = 0;
		notify_disconnect();
		con_print << "^BDisconnected.\n";
	}
}

void Application::frame()
{
	// execute commands in the buffer
	CommandBuffer::exec();

	if (!connected())
		return;

	// run a game interface frame
	application_game->frame(application_timer.timestamp());

	if (!application_game->running())
		disconnect();
}

void Application::save_config()
{
	std::string filename(filesystem::writedir());
	if (!Cvar::sv_dedicated->value())
		filename.append("client.cfg");
	else
		filename.append("server.cfg");
	std::ofstream ofs(filename.c_str());

	if (!ofs.is_open()) {
		con_warn << "Could not write " << filename << std::endl;
		return;
	}

	con_print << "  writing configuration to " << filename << std::endl;

	if (!Cvar::sv_dedicated->value())
		ofs << "# client.cfg - osirion client configuration" << std::endl;
	else
		ofs << "# server.cfg - osiriond dedicated server configuration" << std::endl;

	ofs << "# this file is automaticly generated" << std::endl;
	ofs << std::endl;

	for (Cvar::Registry::iterator it = Cvar::registry().begin(); it != Cvar::registry().end(); it++) {
		if (((*it).second->flags() & Cvar::Archive) == Cvar::Archive) {
			ofs << "# " << (*it).first << " " << (*it).second->info() << std::endl;
			ofs << "set " << (*it).first << " " << (*it).second->str() << std::endl;
			ofs << std::endl;
		}
	}
	ofs.close();
}

void Application::load_config()
{
	std::string filename(filesystem::writedir());
	if (!Cvar::sv_dedicated->value())
		filename.append("client.cfg");
	else
		filename.append("server.cfg");
	std::ifstream ifs(filename.c_str(), std::ifstream::in);

	if (!ifs.is_open()) {
		con_warn << "Could not read " << filename << std::endl;
		return;
	}

	con_print << "  reading configuration from " << filename << std::endl;

	char line[MAXCMDSIZE];
	while (ifs.getline(line, MAXCMDSIZE - 1)) {
		if (line[0] && line[0] != '#' && line[0] != ';')
			CommandBuffer::exec(line);
	}
}

void Application::load_autoexec()
{
	if (Cvar::sv_dedicated->value())
		return;

	std::string filename(filesystem::writedir());
	filename.append("autoexec.cfg");
	std::ifstream ifs(filename.c_str(), std::ifstream::in);

	if (!ifs.is_open()) {
		con_warn << "Could not read " << filename << std::endl;

		std::ofstream ofs(filename.c_str());

		if (!ofs.is_open()) {
			con_warn << "Could not write " << filename << std::endl;
			return;
		}

		ofs << "# autoexec.cfg - osirion client custom settings" << std::endl;
		ofs << "# put your custom settings here" << std::endl;
		ofs.close();

		return;
	} else {

		con_print << "  reading configuration from " << filename << std::endl;

		char line[MAXCMDSIZE];
		while (ifs.getline(line, MAXCMDSIZE - 1)) {
			if (line[0] && line[0] != '#' && line[0] != ';')
				CommandBuffer::exec(line);
		}
	}
}

void Application::load_commandline(int count, char **arguments)
{
	if (count < 2)
		return;

	for (int i = 1; i < count; i++) {
		if (arguments[i][0] == '+') {
			if (i > 1)
				cmd() << '\n';

			if (arguments[i][1])
				cmd() << &arguments[i][1];
		} else {
			if (i > 1)
				cmd() << ' ';
			cmd() << arguments[i];
		}
	}

	cmd() << '\n';
}

void Application::notify_message(const core::Message::Channel channel, const std::string &message)
{
	con_print << message << std::endl;
}

void Application::notify_loader(const std::string &message)
{
	// the default implementation does nothing.
	// used by the client to udpate the loader screen
}

void Application::notify_sound(const char *name)
{
	// the default implementation does nothing.
	// Dedicated servers don't need sounds
}

void Application::notify_zonechange()
{
	// the default implementation does nothing.
	// The client uses this to clear old zones
}

void Application::notify_disconnect()
{
	// the default implementation does nothing.
	// The client uses this to clear game data

}

void Application::notify_connect()
{
}

/* -- static engine functions -------------------------------------- */

void Application::func_help(std::string const &args)
{
	std::istringstream argstream(args);
	std::string topic;
	if (!(argstream >> topic))
		topic.assign("help");

	topic.append(".txt");
	CommandBuffer::print_file("help/" + topic);
}

void Application::func_quit(std::string const  &args)
{
	Application::instance()->shutdown();
	Application::instance()->quit(0);
}

void Application::func_connect(std::string const &args)
{
	std::istringstream argstream(args);
	std::string host;
	if (!(argstream >> host))
		host.clear();

	Application::instance()->connect(host);
}

void Application::func_disconnect(std::string const  &args)
{
	Application::instance()->disconnect();
}

void Application::func_shout(std::string const &args)
{
	if (connection()) {
		connection()->shout(args);
	} else if (server()) {
		server()->shout(localplayer(), args);
	} else {
		con_print << "Not connected." << std::endl;
	}
}

void Application::func_say(std::string const &args)
{
	if (connection()) {
		connection()->say(args);
	} else if (server()) {
		server()->say(localplayer(), args);
	} else {
		con_print << "Not connected." << std::endl;
	}
}

void Application::func_msg(std::string const &args)
{
	if (connection()) {
		connection()->private_message(args);
	} else if (server()) {
		server()->private_message(localplayer(), args);
	} else {
		con_print << "Not connected." << std::endl;
	}
}

void Application::func_rcon(std::string const &args)
{
	if (connection()) {
		core::Cvar *rconpassword = core::Cvar::find("rconpassword");
		if (rconpassword && rconpassword->str().size()) {
			connection()->rcon(args);
		} else {
			con_warn << "rconpassword not set!" << std::endl;
		}
	} else if (server()) {
		cmd() << args << "\n";
	} else {
		con_print << "Not connected." << std::endl;
	}
}

void Application::func_load(std::string const &args)
{
	std::string name(args);
	aux::to_label(name);
	Application::instance()->load(name);
}

void Application::func_info(std::string const &args)
{
	// FIXME connection info etc
}

}