/* notify_mailto.c -- email notification method
 *
 * Copyright (c) 1994-2008 Carnegie Mellon University.  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.
 *
 * 3. The name "Carnegie Mellon University" must not be used to
 *    endorse or promote products derived from this software without
 *    prior written permission. For permission or any legal
 *    details, please contact
 *      Carnegie Mellon University
 *      Center for Technology Transfer and Enterprise Creation
 *      4615 Forbes Avenue
 *      Suite 302
 *      Pittsburgh, PA  15213
 *      (412) 268-7393, fax: (412) 268-7395
 *      innovation@andrew.cmu.edu
 *
 * 4. Redistributions of any form whatsoever must retain the following
 *    acknowledgment:
 *    "This product includes software developed by Computing Services
 *     at Carnegie Mellon University (http://www.cmu.edu/computing/)."
 *
 * CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO
 * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE
 * FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
 * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <config.h>

#include "notify_mailto.h"

#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <time.h>
#include <sys/types.h>
#include <sys/wait.h>

#include "imap/global.h"
#include "libconfig.h"
#include "sieve/sieve_interface.h"
#include "times.h"

static int contains_8bit(const char *msg);

static int global_outgoing_count = 0;

char* notify_mailto(const char *class,
                    const char *priority __attribute__((unused)),
                    const char *user __attribute__((unused)),
                    const char *mailbox __attribute__((unused)),
                    int nopt, char **options,
                    const char *message,
                    const char *fname __attribute__((unused)))
{
    FILE *sm;
    const char *smbuf[7];
    char outmsgid[256];
    int sm_stat;
    time_t t;
    char datestr[RFC822_DATETIME_MAX+1];
    pid_t sm_pid;
    int fds[2];

    /* XXX check/parse options (mailto URI) */
    if (nopt < 1)
        return strdup("NO mailto URI not specified");

    smbuf[0] = "sendmail";
    smbuf[1] = "-i";            /* ignore dots */
    smbuf[2] = "-f";
    smbuf[3] = "<>";            /* XXX do we want a return-path? */
    smbuf[4] = "--";
    smbuf[5] = options[0];
    smbuf[6] = NULL;

    if (pipe(fds))
        return strdup("NO mailto could not open pipe");

    if ((sm_pid = fork()) == 0) {
        /* i'm the child! run sendmail! */
        close(fds[1]);
        /* make the pipe be stdin */
        dup2(fds[0], 0);
        execv(config_getstring(IMAPOPT_SENDMAIL), (char **) smbuf);

        /* if we're here we suck */
        return strdup("NO mailto couldn't exec");
    }
    /* i'm the parent */
    close(fds[0]);
    sm = fdopen(fds[1], "w");

    if (!sm)
        return strdup("NO mailto could not spawn sendmail process");

    t = time(NULL);
    snprintf(outmsgid, sizeof(outmsgid), "<cmu-sieve-%d-%lu-%d@%s>",
             (int) sm_pid, t, global_outgoing_count++, config_servername);

    fprintf(sm, "Message-ID: %s\r\n", outmsgid);

    time_to_rfc822(t, datestr, sizeof(datestr));
    fprintf(sm, "Date: %s\r\n", datestr);

    fprintf(sm, "X-Sieve: %s\r\n", SIEVE_VERSION);
    fprintf(sm, "From: Mail Sieve Subsystem <%s>\r\n", config_getstring(IMAPOPT_POSTMASTER));
    fprintf(sm, "To: <%s>\r\n", options[0]);
    fprintf(sm, "Subject: [%s] New mail notification\r\n", class);
    if (contains_8bit(message)) {
        fprintf(sm, "MIME-Version: 1.0\r\n");
        fprintf(sm, "Content-Type: text/plain; charset=UTF-8\r\n");
        fprintf(sm, "Content-Transfer-Encoding: 8BIT\r\n");
    }
    fprintf(sm, "\r\n");

    fprintf(sm, "%s\r\n", message);

    fclose(sm);
    while (waitpid(sm_pid, &sm_stat, 0) < 0);

    /* XXX check for sendmail exit code */

    /* XXX add outmsgid to duplicate delivery database to prevent loop */

    return strdup("OK mailto notification successful");
}

static int contains_8bit(const char * msg)
{
    int result = 0;

    if (msg) {
        const unsigned char *s = (const unsigned char *)msg;

        while (*s) {
            if (0 != (*s & 0x80)) {
                result = 1;
                break ;
            }
            s++;
        }
    }
    return result;
}