#include <stdlib.h>
#include <string.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <inttypes.h>

#include "main.h"
#include "uring.h"
#include "server.h"
#include "proxy.h"
#include "utils.h"

struct server_local {
	struct sockaddr_in46 addr;
	char addrstr[ADDRSTRLEN];
	struct sockaddr_in46 peer;
	struct uring_task task;
	struct list_head list;
};

void
server_refdump(struct server *server)
{
	struct server_local *local;
	struct server_proxy *proxy;

	uring_task_refdump(&server->task);
	list_for_each_entry(local, &server->locals, list)
		uring_task_refdump(&local->task);
	list_for_each_entry(proxy, &server->proxys, list)
		proxy_refdump(proxy);
}

static void
server_free(struct uring_task *task)
{
	struct server *scfg = container_of(task, struct server, task);

	fprintf(stderr, "Freeing scfg %s\n", scfg->name);
	list_del(&scfg->list);
	free(scfg->pretty_name);
	free(scfg->name);
	free(scfg);
}

void
server_delete(struct cfg *cfg, struct server *scfg)
{
	struct server_local *local, *ltmp;
	struct sockaddr_in46 *remote, *rtmp;

	fprintf(stderr, "Removing server cfg: %s\n", scfg->name);

	list_for_each_entry_safe(remote, rtmp, &scfg->remotes, list) {
		list_del(&remote->list);
		free(remote);
	}

	list_for_each_entry_safe(local, ltmp, &scfg->locals, list) {
		uring_cancel(cfg, &local->task);
	}

	uring_task_put(cfg, &scfg->task);
}

void
server_delete_by_name(struct cfg *cfg, const char *name)
{
	struct server *scfg;

	if (!cfg || !name || name[0] == '\0')
		return;

	list_for_each_entry(scfg, &cfg->servers, list) {
		if (!strcmp(scfg->name, name)) {
			server_delete(cfg, scfg);
			return;
		}
	}
}

static void
server_dump(struct server *scfg)
{
	struct server_local *local;
	struct sockaddr_in46 *remote;
	char abuf[ADDRSTRLEN];

	fprintf(stderr, "Dumping server %s\n", scfg->name);
	switch (scfg->type) {
	case SERVER_TYPE_ANNOUNCE:
		fprintf(stderr, "  * Type: announce\n");
		break;
	case SERVER_TYPE_PROXY:
		fprintf(stderr, "  * Type: proxy\n");
		break;
	default:
		fprintf(stderr, "  * Type: unknown\n");
		break;
	}
	fprintf(stderr, "  * Pretty name: %s\n", scfg->pretty_name ? scfg->pretty_name : "<undefined>");
	fprintf(stderr, "  * Announce port: %" PRIu16 "\n", scfg->announce_port); 
	fprintf(stderr, "  * Listening ports:\n");
	list_for_each_entry(local, &scfg->locals, list)
		fprintf(stderr, "    * %s\n", local->addrstr);
	fprintf(stderr, "  * Remote ports:\n");
	list_for_each_entry(remote, &scfg->remotes, list)
		fprintf(stderr, "    * %s\n", sockaddr_to_str(remote, abuf, sizeof(abuf)));
}

static void
server_local_free(struct uring_task *task)
{
	struct server_local *local = container_of(task, struct server_local, task);

	fprintf(stderr, "%s called: task 0x%p\n", __func__, task);

	list_del(&local->list);
	free(local);
}

static void
server_local_accept(struct cfg *cfg, struct uring_task *task, int res)
{
	struct server_local *local = container_of(task, struct server_local, task);
	struct server *scfg = container_of(task->parent, struct server, task);
	struct server_proxy *proxy;
	char abuf[ADDRSTRLEN];

	fprintf(stderr, "%s called: task 0x%p and res %i\n", __func__, task, res);
	fprintf(stderr, "%s called: scfg name is %s\n", __func__, scfg->name);

	if (task->dead) {
		fprintf(stderr, "Task dead!\n");
		uring_task_put(cfg, task);
		return;
	}

	if (res < 0) {
		fprintf(stderr, "%s: result was %i\n", __func__, res);
		goto out;
	}

	sockaddr_to_str(&local->peer, abuf, sizeof(abuf));
	fprintf(stderr, "%s: incoming proxy connection: %s -> %s\n", scfg->name, abuf, local->addrstr);

	if (list_empty(&scfg->remotes)) {
		error("scfg->remotes empty!\n");
		uring_close(cfg, NULL, res, NULL);
		goto out;
	}

	proxy = proxy_new(cfg, scfg, &local->peer, res);
	if (!proxy)
		uring_close(cfg, NULL, res, NULL);

out:
	uring_accept(cfg, &local->task, &local->peer, server_local_accept);
}

static bool
server_local_open(struct cfg *cfg, struct server *scfg, struct server_local *local)
{
	int sfd;
	int enable = 1;
	int r;

	sfd = socket(local->addr.storage.ss_family, SOCK_STREAM, 0);
	if (sfd < 0) {
		perror("socket");
		goto out;
	}

	if (setsockopt(sfd, SOL_SOCKET, SO_REUSEADDR, &enable, sizeof(enable)) < 0) {
		perror("setsockopt");
		goto out;
	}

	r = bind(sfd, (struct sockaddr *)&local->addr.storage, local->addr.addrlen);
	if (r < 0) {
		perror("bind");
		goto out;
	}

	r = listen(sfd, 100);
	if (r < 0) {
		perror("listen");
		goto out;
	}

	uring_task_set_fd(&local->task, sfd);
	uring_accept(cfg, &local->task, &local->peer, server_local_accept);
	fprintf(stderr, "** Opened listening socket: %s\n", local->addrstr);
	return true;

out:
	if (sfd >= 0)
		close(sfd);
	return false;
}

bool
server_commit(struct cfg *cfg, struct server *scfg)
{
	struct server_local *local;
	uint16_t port;

	if (!scfg || !scfg->name)
		return false;

	if (!list_empty(&scfg->proxys))
		return false;

	/* FIXME: running? */

	switch (scfg->type) {
	case SERVER_TYPE_ANNOUNCE:
		if (scfg->announce_port < 1)
			return false;
		if (!list_empty(&scfg->locals))
			return false;
		if (!list_empty(&scfg->remotes))
			return false;
		break;

	case SERVER_TYPE_PROXY:
		if (scfg->announce_port >= 1)
			return false;
		if (list_empty(&scfg->locals))
			return false;
		if (list_empty(&scfg->remotes))
			return false;

		list_for_each_entry(local, &scfg->locals, list) {
			port = sockaddr_port(&local->addr);

			if (port == 0)
				return false;

			if (scfg->announce_port < 1)
				scfg->announce_port = port;

			if (scfg->announce_port != port) {
				fprintf(stderr, "Multiple announce ports!?\n");
				return false;
			}
		}

		if (scfg->announce_port < 1)
			return false;

		break;

	default:
		return false;
	}

	if (!scfg->pretty_name) {
		char *suffix;
		
		suffix = strrchr(scfg->name, '.');
		if (!suffix || suffix == scfg->name)
			return false;

		scfg->pretty_name = strndup(scfg->name, suffix - scfg->name);
		if (!scfg->pretty_name)
			return false;
	}

	/* FIXME: config, dont reread config if server running, make sure fd is available before this is called */
	server_dump(scfg);

	list_for_each_entry(local, &scfg->locals, list) {
		server_local_open(cfg, scfg, local);
	}
	return true;
}

bool
server_add_remote(struct cfg *cfg, struct server *scfg, struct sockaddr_in46 *addr)
{
	if (!scfg || !addr)
		return false;

	list_add(&addr->list, &scfg->remotes);
	return true;
}

bool
server_add_local(struct cfg *cfg, struct server *scfg, struct sockaddr_in46 *addr)
{
	struct server_local *local;

	if (!scfg || !addr)
		return false;

	local = zmalloc(sizeof(*local));
	if (!local)
		return false;

	local->addr.storage = addr->storage;
	local->addr.addrlen = addr->addrlen;
	uring_task_init(&local->task, "local", &scfg->task, server_local_free);
	sockaddr_to_str(&local->addr, local->addrstr, sizeof(local->addrstr));
	fprintf(stderr, "Adding local: %s\n", local->addrstr);
	list_add(&local->list, &scfg->locals);
	free(addr);
	return true;
}

bool
server_set_port(struct cfg *cfg, struct server *scfg, uint16_t port)
{
	if (!scfg || scfg->announce_port != 0)
		return false;

	scfg->announce_port = htons(port);
	return true;
}

bool
server_set_type(struct cfg *cfg, struct server *scfg, enum server_type type)
{
	if (!scfg || scfg->type != SERVER_TYPE_UNDEFINED)
		return false;

	switch (type) {
	case SERVER_TYPE_ANNOUNCE:
		scfg->type = SERVER_TYPE_ANNOUNCE;
		break;
	case SERVER_TYPE_PROXY:
		scfg->type = SERVER_TYPE_PROXY;
		break;
	default:
		return false;
	}

	return true;
}

bool
server_set_pretty_name(struct cfg *cfg, struct server *scfg, const char *pretty_name)
{
	if (!pretty_name || pretty_name[0] == '\0' || !scfg || scfg->pretty_name)
		return false;

	scfg->pretty_name = strdup(pretty_name);
	if (!scfg->pretty_name)
		return false;

	return true;
}

struct server *
server_new(struct cfg *cfg, const char *name)
{
	struct server *scfg;

	list_for_each_entry(scfg, &cfg->servers, list) {
		if (strcmp(name, scfg->name))
			continue;
		debug(2, "Server already exists: %s\n", name);
		return scfg;
	}

	debug(2, "Would add server cfg: %s\n", name);
	scfg = zmalloc(sizeof(*scfg));
	if (!scfg) {
		error("malloc");
		return NULL;
	}

	scfg->type = SERVER_TYPE_UNDEFINED;
	scfg->name = strdup(name);
	scfg->running = false;
	uring_task_init(&scfg->task, "scfg", uring_parent(cfg), server_free);
	list_init(&scfg->remotes);
	list_init(&scfg->locals);
	list_init(&scfg->proxys);
	memset(&scfg->mcast_iov, 0, sizeof(scfg->mcast_iov));
	scfg->mcast_iov.iov_base = scfg->mcast_buf;
	memset(&scfg->mcast_msg, 0, sizeof(scfg->mcast_msg));
	scfg->mcast_msg.msg_iov = &scfg->mcast_iov;
	scfg->mcast_msg.msg_iovlen = 1;
	list_add(&scfg->list, &cfg->servers);

	return scfg;
}