/* B01902062 藍挺瑋 */
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#include "server.h"
#include "common.h"

#include <assert.h>
#include <arpa/inet.h>
#include <errno.h>
#include <fcntl.h>
#include <netdb.h>
#include <netinet/in.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/select.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <sys/types.h>
#include <unistd.h>


// You don't need to know how the following codes are working

void server_init(server* svr, unsigned short port, int maxfd) {
	struct sockaddr_in servaddr;
	int val, flags;

	gethostname(svr->hostname, sizeof(svr->hostname));
	svr->port = port;

	svr->listen_fd = socket(AF_INET, SOCK_STREAM, 0);
	if (svr->listen_fd < 0)
		e_err_exit("socket");

	memset(&servaddr, 0, sizeof(servaddr));
	servaddr.sin_family = AF_INET;
	servaddr.sin_addr.s_addr = htonl(INADDR_ANY);
	servaddr.sin_port = htons(port);
	val = 1;
	if (setsockopt(svr->listen_fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val)) < 0)
		e_err_exit("setsockopt");
	if (bind(svr->listen_fd, (struct sockaddr*)&servaddr, sizeof(servaddr)) < 0)
		e_err_exit("bind");
	if (listen(svr->listen_fd, 1024) < 0)
		e_err_exit("listen");

	strcpy(svr->accept_hdr, "ACCEPT\n");
	strcpy(svr->reject_hdr, "REJECT\n");

	FD_ZERO(&svr->readfds);
	FD_ZERO(&svr->writefds);
	FD_ZERO(&svr->exceptfds);
	FD_SET(svr->listen_fd, &svr->readfds);

	flags = fcntl(svr->listen_fd, F_GETFL);
	if(flags < 0){
		perror("Warning: F_GETFL");
		return;
	}
	fcntl(svr->listen_fd, F_SETFL, flags | O_NONBLOCK);

	svr->file_table = ftab_create (maxfd);
}

void server_free(server* svr) {
	ftab_free (svr->file_table);
}

void request_init(request* reqP) {
	reqP->conn_fd = -1;
	reqP->buf_set = 0;
	reqP->buf_len = 0;
	reqP->filename = NULL;
	reqP->file_fd = -1;
	reqP->file_info = NULL;
	reqP->active = false;
	reqP->header_done = false;
	reqP->header_accept = false;
}

void request_free(request* reqP, server* svr) {
	if (reqP->filename != NULL) {
		free(reqP->filename);
		reqP->filename = NULL;
	}

	shutdown (reqP->conn_fd, SHUT_RDWR);
	close (reqP->conn_fd);

	if (reqP->file_info != NULL)
		fnode_unref (reqP->file_info, svr->file_table);

	if (svr != NULL) {
		FD_CLR (reqP->conn_fd, &(svr->readfds));
		FD_CLR (reqP->conn_fd, &(svr->writefds));
		FD_CLR (reqP->conn_fd, &(svr->exceptfds));
	}

	request_init(reqP);
}

int request_read(request* reqP) {
	int r;
	char buf[SVR_BUFFER_SIZE];

	// Read in request from client
	r = read(reqP->conn_fd, buf, sizeof(buf));
	if (r < 0) return -1;
	if (r == 0) return 0;
	if (!reqP->header_done) {
		char* p1 = strstr(buf, "\r\n");
		int newline_len = 2;
		// be careful that in Windows, line ends with \r\n
		if (p1 == NULL) {
			p1 = strchr(buf, '\n');
			newline_len = 1;
			if (p1 == NULL) {
				char* pfn = e_malloc (sizeof (char) * (r + 1));
				memmove (pfn, buf, r);
				pfn[r] = '\0';
				if (reqP->filename == NULL) {
					reqP->filename = pfn;
				} else {
					char* newpfn = e_strcat (reqP->filename, pfn);
					free (reqP->filename);
					reqP->filename = newpfn;
					free (pfn);
				}
				return 1;
			}
		}
		size_t len = p1 - buf + 1;
		char* fn = (char*)e_malloc(len);
		memmove(fn, buf, len - 1);
		fn[len - 1] = '\0';
		if (reqP->filename == NULL) {
			reqP->filename = fn;
		} else {
			char* newfn = e_strcat (reqP->filename, fn);
			free (reqP->filename);
			reqP->filename = newfn;
			free (fn);
		}
		p1 += newline_len;
		reqP->buf_len = r - (p1 - buf);
		memmove(reqP->buf, p1, reqP->buf_len);
		reqP->header_done = true;
	} else {
		reqP->buf_len = r;
		memmove(reqP->buf, buf, r);
	}
	return 1;
}

void request_msg (request* reqP, const char* format, ...) {
	va_list ap;
	va_start (ap, format);
	printf ("client %d from %s: %s: ", reqP->conn_fd, reqP->host,
		reqP->filename ? reqP->filename : "(no filename)");
	vprintf (format, ap);
	putchar ('\n');
	va_end (ap);
}

void request_err (request* reqP, const char* key, int chkrval) {
	request_msg (reqP, "%s %s%s", key,
		chkrval < 0 ? "error: " : "done",
		chkrval < 0 ? strerror(errno) : "");
}