#include <poll.h>
#include <stdio.h>
#include <unistd.h>

#include <lua.h>

#include "plop.h"

/// Prints program usage to standard error.
/// \param name Name of the executable from argv
static void usage(const char * const name)
{
	dprintf(2,
		"Usage: %s [-p PORT] [-h] [HANDLER]\n"
		"Starts plop server listening on PORT and serving HANDLER.\n"
		"HANDLER defaults to '" PLOP_DEFAULT_HANDLER "'.\n\n"
		"  -p\tstart listening on PORT (default: 8080)\n"
		"  -h\tprints this help message\n",
		name);
}

/// Standard entry point for the program.
/// \param argc Argument count
/// \param argv Argument array
/// \return Error code
int main(int argc, char ** argv)
{
	const char * service = "8080";
	int opt;

	while (-1 != (opt = getopt(argc, argv, "p:h")))
	{
		switch (opt)
		{
			case 'p':
			{
				service = optarg;
				break;
			}
			case 'h':
			{
				usage(argv[0]);
				return 0;
			}
			default:
			{
				usage(argv[0]);
				return 1; // TODO: Extend error handling in main().
			}
		}
	}

	if (optind < argc)
	{
		plop.handler = argv[optind];
	}

	plop.L = plop_initialize_lua();

	if (NULL == plop.L)
	{
		return 9;
	}

	if (LUA_OK != plop_load_handler(plop.L, plop.handler))
	{
		return 2;
	}

	static const int nfds = 50;  // TODO-maybe: Expand, allow setting default starting value?
	struct pollfd fds[nfds];
	struct connection * data[nfds];
	for (int i = 0; i < nfds; ++i)
	{
		fds[i].fd = -1;
		fds[i].events = POLLIN;  // TODO: Handle yielded writes
		data[i] = NULL;
	}
	const int server = open_server(NULL, service);
	if (-1 == server)
		return 4;
	fds[0].fd = server;
	fds[0].events = POLLIN;
	plop.fds = fds;
	plop.data = data;
	plop.nfds = nfds;
	while (1)
	{
		int ret = poll(fds, nfds, -1);  // TODO-maybe: Specify timeout and allow timers?
		if (-1 == ret)
			return 5;
		for (int i = 0; i < nfds; ++i)
		{
			if (-1 == fds[i].fd || 0 == fds[i].revents)
				continue;
			if (NULL == data[i])
			{
				if (-1 == plop_handle_server(server))
					return 6;
			}
			else
			{
				ret = plop_handle_client(data[i]);
				if (-1 == ret)
					return 7;
				else if (0 == ret)
					fds[i].fd = -1;
			}
		}
	}
}