#include <signal.h>
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <syslog.h>
#include <unistd.h>
#include "config.h"
#include "git.h"
#include "linked_list.h"
#include "macros.h"
#include "network.h"

#define UNIX_PATH_MAX 108

pid_t fork_proc() {
	/* Fork off the parent. */
	pid_t pid = fork();

	/* The process id is non zero, so it must be the parent process. */
	if (pid) {
		/* Exit with EXIT_FAILURE if the parent's pid is
		 * negative, otherwise exit with EXIT_SUCCESS.
		 */
		exit((pid < 0) ? EXIT_FAILURE : EXIT_SUCCESS);
	}
	return pid;
}

void child_handler(int sig_num) {
	signal(SIGCHLD, child_handler);
}

void hangup_handler(int sig_num) {
	signal(SIGHUP, hangup_handler);
}

void init_daemon(int change_dir, char *path) {
	/* Fork the parent. */
	pid_t pid = fork_proc();

	/* Exit if the child process isn't the session leader. */
	if (setsid() < 0) {
		exit(EXIT_FAILURE);
	}

	/* Catch, ignore, and/or handle signals. */
	signal(SIGCHLD, child_handler);
	signal(SIGHUP, hangup_handler);

	/* Fork again. */
	pid = fork_proc();

	/* Set new file permissions. */
	umask(0);

	/* If change_dir is true, change the working directory to path, or
	 * the root directory if path isn't set.
	 */
	if (change_dir) {
		chdir((!path) ? "/" : path);
	}

	/* Close any open file descriptors. */
	for (int i = sysconf(_SC_OPEN_MAX); i >= 0; close(i--));
}

int init_config(char *config_file, config **cfg) {
	log(LOG_INFO, "Reading config file %s.", config_file);

	*cfg = parse_config(config_file);

	/* Did the config file parser succeed? */
	if (*cfg != NULL) {
		log(LOG_INFO, "Successfully read %s.", config_file);
	} else {
		log(LOG_ERR, "Error reading %s.", config_file);
	}

	return (*cfg != NULL);
}

int *init_socket(config *cfg) {
	linked_list *sock_list = NULL;
	int *sock_arr = NULL;
	/* Set socket type to unix socket, if socket-type was set to unix, otherwise set it to network socket. */
	const int sock_type = (strcasecmp(cfg->sock_type, "unix") == 0) ? AF_UNIX : AF_INET;

	if (sock_type == AF_UNIX) {
		size_t path_length = strlen(cfg->sock);
		/* Is the path too long? */
		if (path_length >= UNIX_PATH_MAX) {
			log(LOG_ERR, "The socket path is too long, and exceeded %i characters.", UNIX_PATH_MAX);
			return NULL;
		} else {
			int fd;
			struct sockaddr_un sa_un;
			sa_un.sun_family = sock_type;
			memcpy(sa_un.sun_path, cfg->sock, path_length+1);

			fd = create_socket((struct sockaddr *)&sa_un, sizeof(struct sockaddr_un));

			if (fd < 0) {
				return NULL;
			} else {
				int *sock = calloc(1, sizeof(int));
				*sock = fd;
				sock_list = add_node(&sock_list, sock);
			}
		}
	} else {
		struct addrinfo hints, *ainfo_root, *ainfo;

		memset(&hints, 0, sizeof(hints));

		hints.ai_family = AF_UNSPEC;
		hints.ai_socktype = SOCK_SEQPACKET;
		hints.ai_protocol = IPPROTO_SCTP;
		hints.ai_flags = AI_PASSIVE;

		const int gai_ret = getaddrinfo(cfg->sock, cfg->port, &hints, &ainfo_root);
		/* Did getaddrinfo fail? */
		if (gai_ret) {
			log_reason(LOG_ERR, "getaddrinfo() failed for hostname %s.", cfg->sock, gai_strerror(gai_ret));
			return NULL;
		}

		for (struct addrinfo *ai = ainfo_root; ai != NULL; ai = ai->ai_next) {
			const int fd = create_socket(ai->ai_addr, ai->ai_addrlen);
			if (fd >= 0) {
				int *sock = calloc(1, sizeof(int));
				*sock = fd;
				sock_list = add_node(&sock_list, sock);
				log(LOG_DEBUG, "ip addr: \"%s\"", addr_to_str(ai->ai_addr, ai->ai_addrlen));
			}
		}

		freeaddrinfo(ainfo_root);
	}

	int sock_count = linked_list_size(sock_list);
	sock_arr = calloc(sock_count+1, sizeof(int));
	sock_arr[sock_count--] = -1;

	for (linked_list *node = sock_list; node != NULL; node = node->prev, --sock_count) {
		int *sock = (int *)node->data;
		sock_arr[sock_count] = *sock;
		node->data = NULL;
		free(sock);
	}

	log(LOG_NOTICE, "Successfully created %i sockets for hostname \"%s\".", linked_list_size(sock_list), (cfg->sock != NULL) ? cfg->sock : "*");

	cleanup_linked_list(sock_list);

	return sock_arr;
}

int main_loop(config *cfg, int *listen_sockets, git_repo **repos) {
	int done = 0;
	struct stat st;

	/* Does the PR root directory exist? */
	if (stat(cfg->pr_root, &st) < 0) {
		/* Create the PR root directory. */
		mkdir(cfg->pr_root, 0755);
	}

	for (; !done;) {
		break;
	}

	return 0;
}

void cleanup(config *cfg, int *listen_sockets, git_repo **repos) {
	if (listen_sockets != NULL) {
		for (int i = 0; listen_sockets[i] >= 0; ++i) {
			struct sockaddr *sa = get_sock_addr(listen_sockets[i]);
			/* Close the socket. */
			close(listen_sockets[i]);
			/* Is this a unix domain socket? */
			if (sa->sa_family == AF_UNIX) {
				struct sockaddr_un *sa_un = (struct sockaddr_un *)sa;
				/* Unlink the path. */
				unlink(sa_un->sun_path);
			}
			free(sa);
		}
		free(listen_sockets);
	}

	if (cfg) {
		cleanup_config(cfg);
	}

	if (repos) {
		cleanup_git(repos);
	}
}

int main(int argc, char **argv) {
	config *cfg = NULL;
	git_repo **repos = NULL;
	char *config_file = "test.conf";
	int config_read = 0;
	int *listen_sockets = NULL;
	int exit_status = EXIT_FAILURE;

	/* Start it in daemon mode. */
	init_daemon(1, "/");

	/* Open the logfile. */
	openlog("pullreqd", LOG_PID, LOG_DAEMON);

	log(LOG_NOTICE, "pullreqd started.");

	/* Read the config file. */
	config_read = init_config(config_file, &cfg);

	/* Did we successfully read the config file? */
	if (config_read) {
		/* Create the Listen socket(s). */
		listen_sockets = init_socket(cfg);
	}

	/* Did we successfully read the config file, and create any listen sockets? */
	if (config_read && listen_sockets != NULL) {
		repos = init_git(cfg);
		if (repos != NULL) {
			exit_status = main_loop(cfg, listen_sockets, repos);
		}
	}

	cleanup(cfg, listen_sockets, repos);

	log(LOG_NOTICE, "pullreqd stopped.");

	closelog();

	return exit_status;
}