/*
	Copyright © 2015 Gluzskiy Alexandr (sss)

    This file is part of Unknown Download Manager (UDM).

    UDM 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.

    UDM 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 UDM.  If not, see <http://www.gnu.org/licenses/>.

*/
#include <boost/program_options.hpp>
#include <boost/filesystem.hpp>
#include <boost/asio.hpp>
#include <iostream>
#include <map>

#include <signal.h>

#include "api_module_metadata_storage.h"
#include "modules_handler.h"
#include "utilities.h"
#include "server.h"
#include "main.h"
#include "config.h"
#include "client.h"
#include "download_internal.h"

core_api *module_api = nullptr;

modules_handler *modules = nullptr;

namespace bpo = boost::program_options;


std::map<std::string, client*> clients; //auth token used for key

runtime_config_s runtime_config;

std::map<int, download_internal_s> downloads;


server *serv = nullptr;

//TODO: "core" config section architecture, define base settings

void on_exit()
{
	serv->terminate();
	bpt::write_info(runtime_config.config_file_path, runtime_config.config_file); //save config on sigint
	for(auto m : modules->get_downloader_modules())
		delete m;
	for(auto m : modules->get_metadata_modules())
		delete m;
}

void sig_handler(int sig)
{
    switch(sig)
    {
    default:
    {
        on_exit();
        exit(0);
    }
    break;
    }
}

extern "C" int main(int argc, char *argv[])
{
	//handle signals
	signal(SIGINT, sig_handler);
	signal(SIGTERM, sig_handler);
	signal(SIGABRT, sig_handler);

	//this will not work
	signal(SIGKILL, sig_handler);
	signal(SIGSTOP, sig_handler);



	bpo::options_description desc("Available commands and options");
	desc.add_options()
		("help,h", "this message")
		("daemon,d", "fork to background (must be combined with \"--run\", does nothing alone)")
		("config,c", bpo::value<std::string>(), "use specified config file instead of \"~/.config/udm/udm.conf\"")
		("list-modules", "list all installed modules (you can set verbosity level, accepted values from 0 to 1, default = 0)")
		("verbosity,v", bpo::value<short>()->default_value(0), "set global verbosity level")
		("run", "start UDM server")
	;

	bool daemon = false, run = false;
	std::string config_path = "~/.config/udm/udm.conf", parsed_config_path;
	try{

		bpo::variables_map vm;
		bpo::store(bpo::command_line_parser(argc, argv).options(desc).style(bpo::command_line_style::unix_style | bpo::command_line_style::allow_long_disguise).run(), vm);
		bpo::notify(vm);

		//load config first, as it may be needed for other commands
		if(vm.count("config"))
			config_path = vm["config"].as<std::string>();

		{
			parsed_config_path = replace_home_var(config_path);
			if(boost::filesystem::exists(parsed_config_path) && boost::filesystem::is_regular(parsed_config_path))
				bpt::read_info(parsed_config_path, runtime_config.config_file); //TODO: finish this
			else
				std::cerr<<"failed to load config: \"" + config_path + "\", file does not exists or is not regular file\n";
			runtime_config.config_file_path = parsed_config_path;
		}
		{
			auto server_pt = runtime_config.config_file.find("server");
			if(server_pt == runtime_config.config_file.not_found())
			{
				runtime_config.config_file.put("server", "");
				server_pt = runtime_config.config_file.find("server");
			}
			auto it = server_pt->second.find("port");
			if(it == server_pt->second.not_found())
				server_pt->second.put("port", 6613);
			it = server_pt->second.find("password");
			if(it == server_pt->second.not_found())
				server_pt->second.put("password", "");
			it = server_pt->second.find("default_download_directory");
			if(it == server_pt->second.not_found())
				server_pt->second.put("default_download_directory", "~/udm/downloads");
			it = server_pt->second.find("default_metadata_module");
			if(it == server_pt->second.not_found())
				server_pt->second.put("default_metadata_module", "flat_files_metadata");
			it = server_pt->second.find("daemon");
			if(it == server_pt->second.not_found())
				server_pt->second.put("daemon", false);
			it = server_pt->second.find("verbosity");
			if(it == server_pt->second.not_found())
				server_pt->second.put("verbosity", 0);
			it = server_pt->second.find("enable_encryption");
			if(it == server_pt->second.not_found())
				server_pt->second.put("enable_encryption", false);
			it = server_pt->second.find("ssl_certificate");
			if(it == server_pt->second.not_found())
				server_pt->second.put("ssl_certificate", "~/config/udm/cert.crt");
			it = server_pt->second.find("ssl_key");
			if(it == server_pt->second.not_found())
				server_pt->second.put("ssl_key", "~/config/udm/cert.key");
			it = server_pt->second.find("ssl_ca");
			if(it == server_pt->second.not_found())
				server_pt->second.put("ssl_ca", "~/config/udm/ca.crt");
			it = server_pt->second.find("ssl_dh");
			if(it == server_pt->second.not_found())
				server_pt->second.put("ssl_dh", "~/config/udm/dh.pem");
		}
		//load all config variables here
		runtime_config.settings.verbosity = runtime_config.config_file.get<short>("server.verbosity", 0);
		daemon = runtime_config.config_file.get<bool>("server.daemon", false);
		//override config from command line here
		if(vm.count("verbosity"))
		{
			runtime_config.settings.verbosity = vm["verbosity"].as<short>();
		}

		if(vm.count("help"))
		{
			std::cout<<desc<<std::endl;
			return 0;
		}
		if(vm.count("daemon"))
		{
			daemon = true;
		}
		if(vm.count("list-modules"))
		{
			if(!module_api)
				module_api = new core_api;
			if(!modules)
			{
				modules = new modules_handler;
				modules->load_modules();
			}
			std::cout<<modules->list_modules();
			bpt::write_info(parsed_config_path, runtime_config.config_file); //save config on exit
			return 0;
		}
		if(vm.count("run"))
		{
			run = true;
		}
	}
	catch(std::exception &e)
	{
		std::cerr<<"error: "<<e.what()<<std::endl;
		std::cout<<desc<<std::endl;
		return -1;
	}
	catch(...)
	{
		//noop
		return -1;
	}
	if(run)
	{
		if(!module_api)
			module_api = new core_api;
		if(!modules)
		{
			modules = new modules_handler;
			modules->load_modules();
		}

		std::string default_metadata_module_name = runtime_config.config_file.get<std::string>("server.default_metadata_module", "");
		if(default_metadata_module_name == "")
		{
			if(!modules->get_metadata_modules().empty())
				runtime_config.default_metadata_storage = static_cast<module_metadata_storage*>(*(modules->get_metadata_modules().begin()));
			else
				std::cerr<<"Error: Metadata storage modules not installed'n";
		}
		else
		{
			for(auto i = modules->get_metadata_modules().begin(), end = modules->get_metadata_modules().end(); i != end; ++i)
			{
				if((*i)->get_module_info().name == default_metadata_module_name)
					runtime_config.default_metadata_storage = static_cast<module_metadata_storage*>(*i);
			}
			if(!runtime_config.default_metadata_storage)
			{
				std::cerr<<"Error: Failed to load metadata storage module named \""<<default_metadata_module_name<<"\" as default metadata storage module\n";
			}
		}
		if(!runtime_config.default_metadata_storage)
		{
			std::cerr<<"Error: Failed to set default metadata storage module\n";
			return -1;
		}
		modules->on_modules_loaded(); //call second initialization stage in modules
		modules->sync_downloads(downloads);

		if(daemon)
		{
			//TODO: fork here
		}
		boost::asio::io_service io_service_server;
		try{
			//TODO: server options ip address, interface name
			serv = new server(io_service_server, runtime_config, clients, downloads, runtime_config.config_file.get<int>("server.port", 6613));
		}
		catch(std::exception &e)
		{
			//TODO:
		}
		catch(...)
		{
			//TODO:
		}
		//TODO: run in separate thread ?
		boost::system::error_code ec;
		io_service_server.run(ec);
		if(ec)
		{
			//TODO:
		}


		//TODO: run here
		return 0; //stub for now
	}
	std::cerr<<"error: no command specified"<<std::endl;
	std::cout<<desc<<std::endl;

	bpt::write_info(parsed_config_path, runtime_config.config_file); //save config on exit



	return 0;
}