/*
 * Copyright (c) 2007 Hypertriton, Inc. <http://hypertriton.com/>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
 * USE OF THIS SOFTWARE EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * Simple SMTP client routines.
 */

#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>

#include <unistd.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <stdlib.h>

#include "smtp.h"
#include "pathnames.h"

static int
SMTP_Expect(FILE *f, const char *code)
{
	char *buf, *lbuf = NULL;
	size_t len;
	int rv = 0;

	if ((buf = fgetln(f, &len)) == NULL) {
		fprintf(stderr, "EOF from server\n");
		return (0);
	}
	if (buf[len-1] == '\n') {
		buf[len-1] = '\0';
	} else {
		if ((lbuf = malloc(len+1)) == NULL) {
			fprintf(stderr, "malloc linebuf\n");
			return (0);
		}
		memcpy(lbuf, buf, len);
		lbuf[len] = '\0';
		buf = lbuf;
	}
	if (code[0] != buf[0]) {
		fprintf(stderr, "Server returned \"%s\" (was expecting %s)\n",
		    buf, code);
		rv = 0;
	}
	if (lbuf != NULL) { free(lbuf); }
	return (1);
}

/* Inject a message via SMTP */
int
SMTP_Inject(const char *msg, size_t msgLen, const char *from, const char *rcpt,
    const char *host, const char *port)
{
	struct addrinfo hints, *res, *res0;
	const char *cause = NULL;
	int rv, s;
	FILE *f;

	memset(&hints, 0, sizeof(hints));
	hints.ai_family = PF_UNSPEC;
	hints.ai_socktype = SOCK_STREAM;
	if ((rv = getaddrinfo(host, port, &hints, &res0)) != 0) {
		fprintf(stderr, "%s:%s: %s\n", host, port, gai_strerror(rv));
		return (-1);
	}
	for (s = -1, res = res0;
	     res != NULL;
	     res = res->ai_next) {
		s = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
		if (s < 0) {
			cause = "socket";
			continue;
		}
		if (connect(s, res->ai_addr, res->ai_addrlen) < 0) {
			cause = "connect";
			close(s);
			s = -1;
			continue;
		}
		break;
	}
	if (s == -1) {
		fprintf(stderr, "%s: %s\n", cause, strerror(errno));
		goto fail_addr;
	}
	if ((f = fdopen(s, "w+")) == NULL) {
		fprintf(stderr, "fdopen: %s\n", strerror(errno));
		goto fail;
	}
	if (setvbuf(f, NULL, _IOLBF, 0) == EOF) {
		printf("setvbuf failed\n");
	}
	if (!SMTP_Expect(f, "2")) { goto fail; }
	fputs("HELO [127.0.0.1]\n", f);
	if (!SMTP_Expect(f, "2")) { goto fail; }
	fputs("MAIL FROM:<", f);
	fputs(from, f);
	fputs(">\n", f);
	if (!SMTP_Expect(f, "2")) { goto fail; }
	fputs("RCPT TO:<", f);
	fputs(rcpt, f);
	fputs(">\n", f);
	if (!SMTP_Expect(f, "2")) { goto fail; }
	fputs("DATA\n", f);
	if (!SMTP_Expect(f, "3")) { goto fail; }
	fputs(msg, f);
	fputs("\r\n.\r\n", f);
	if (!SMTP_Expect(f, "2")) { goto fail; }
	close(s);
	freeaddrinfo(res0);
	return (0);
fail:
	close(s);
fail_addr:
	freeaddrinfo(res0);
	return (-1);
}