/*
   $Source: /v/ossp/cvs/ossp-pkg/petidomo/hermes.c,v $
   $Revision: 1.2 $

   Copyright (C) 2000 by CyberSolutions GmbH, Germany.

   This file is part of OpenPetidomo.

   OpenPetidomo is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2, or (at your option)
   any later version.

   OpenPetidomo is distributed in the hope that it will be useful, but
   WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
   General Public License for more details.
*/

#include <sys/types.h>
#include <sys/stat.h>
#include <string.h>

#include "libtext/text.h"
#include "petidomo.h"

int
hermes_main(char * incoming_mail, const char * listname)
{
    const struct PD_Config *     MasterConfig;
    const struct List_Config *   ListConfig;
    struct stat     sb;
    struct Mail *   MailStruct;
    FILE *          fh;
    char *          PostingHeaders;
    char *          currLine;
    char *          nextLine;
    char *          dst;
    char *          parameter;
    char *          buffer;
    char            envelope[1024];
    char            owner[1024];
    int             rc, len, operation;

    assert(listname != NULL);
    debug((DEBUG_HERMES, 5, "Received article for the \"%s\" mailing list", listname));

    /* Initialize internals. */

    ListConfig = getListConfig(listname);

    /* Parse the incoming mail. */

    rc = ParseMail(&MailStruct, incoming_mail, ListConfig->fqdn);
    if (rc != 0) {
	syslog(LOG_ERR, "Parsing the incoming mail failed.");
	exit(rc);
    }

    debug((DEBUG_HERMES, 3, "Parsed incoming mail successfully."));

    /* Do sanity checks. */

    if (MailStruct->Envelope == NULL) {
	syslog(LOG_NOTICE, "Received mail without a valid envelope.");
	return 0;
    }
    if (MailStruct->From == NULL) {
	syslog(LOG_NOTICE, "Received mail without From: line.");
	return 0;
    }
    if (*MailStruct->Body == '\0') {
	syslog(LOG_NOTICE, "Received mail with empty body.");
	return 0;
    }

    /* Initialize internal stuff. */

    if (isValidListName(listname) == FALSE) {
	syslog(LOG_ERR, "Mailing list \"%s\" does not exist.", listname);
	exit(1);
    }
    PostingHeaders = xmalloc(strlen(MailStruct->Header)+1024);
    MasterConfig = getMasterConfig();
    sprintf(envelope, "%s-owner@%s", listname, ListConfig->fqdn);
    sprintf(owner, "%s-owner@%s", listname, ListConfig->fqdn);

    /* Check for authorization. */

    debug((DEBUG_HERMES, 5, "Checking whether posting is authorized."));

    if (FindBodyPassword(MailStruct) != 0)
      exit(1);

    if (isValidPostingPassword(MailStruct->Approve, listname) == FALSE) {

	/* No valid password found. Reject the article, if the list is
	   of type 'moderated'. */

	if (ListConfig->listtype == LIST_MODERATED) {
	    syslog(LOG_NOTICE, "\"%s\" tried to post to list \"%s\", but failed to " \
		"provide a correct password.", MailStruct->From, listname);

	    fh = vOpenMailer(envelope, owner, NULL);
	    if (fh != NULL) {
		fprintf(fh, "From: %s (Petidomo Mailing List Server)\n", owner);
		fprintf(fh, "To: %s\n", owner);
		fprintf(fh, "Subject: Unauthorized posting to list \"%s\"\n", listname);
		fprintf(fh, "Precedence: junk\n");
		fprintf(fh, "Sender: %s\n", owner);
		fprintf(fh, "\n");
		fprintf(fh, "The following article was rejected:\n\n");
		fprintf(fh, "%s\n", MailStruct->Header);
		fprintf(fh, "%s", MailStruct->Body);
		CloseMailer(fh);
	    }
	    else {
		syslog(LOG_ERR, "Failed to send email to \"%s\" concerning this request.",
		    owner);
		return -1;
	    }
	    return 0;
	}

	if (ListConfig->listtype == LIST_CLOSED) {
	    /* Only subscribers may post */
	    if (isSubscribed(listname, MailStruct->From, NULL, NULL, TRUE) == FALSE) {
		debug((DEBUG_HERMES, 5, "\"%s\" is not a subscriber of \"%s\". Rejecting.",
		       MailStruct->From, listname));

		fh = vOpenMailer(envelope, owner, NULL);
		if (fh != NULL) {
		    fprintf(fh, "From: %s (Petidomo Mailing List Server)\n", owner);
		    fprintf(fh, "To: %s\n", owner);
		    fprintf(fh, "Subject: Unauthorized posting to list \"%s\"\n", listname);
		    fprintf(fh, "Precedence: junk\n");
		    fprintf(fh, "Sender: %s\n", owner);
		    fprintf(fh, "\n");
		    fprintf(fh, "The following article was rejected, because the sender\n" \
			    "\"%s\" is not subscribed to the list:\n\n", MailStruct->From);
		    fprintf(fh, "%s\n", MailStruct->Header);
		    fprintf(fh, "%s", MailStruct->Body);
		    CloseMailer(fh);
		}
		else {
		    syslog(LOG_ERR, "Failed to send email to \"%s\" concerning this request.",
			owner);
		    return -1;
		}
		return 0;
	    }
	}

	if (checkACL(MailStruct, listname, &operation, &parameter) != 0) {
	    syslog(LOG_ERR, "checkACL() failed with an error.");
	    exit(1);
	}
	rc = handleACL(MailStruct, listname, operation, parameter);
	debug((DEBUG_HERMES, 8, "handleACL() returned %d.", rc));
	switch(rc) {
	  case -1:
	      syslog(LOG_ERR, "handleACL() failed with an error.");
	      exit(1);
	  case 0:
	      break;
	  case 1:
	      return 0;
	}

	debug((DEBUG_HERMES, 3, "\"%s\" is authorized to post to \"%s\".",
	       MailStruct->From, listname));
    }
    else {
	debug((DEBUG_HERMES, 5, "Listtype doesn't require authorization."));
    }

    /* Copy the desired headers from the original mail to our own
       buffer. */

    debug((DEBUG_HERMES, 9, "Preparing headers for posting."));
    for(len = 0, currLine = MailStruct->Header, dst = PostingHeaders;
	*currLine != '\0';
	currLine = nextLine) {

	/* Find next header line. */

	nextLine = text_find_next_line(currLine);
	while (*nextLine == '\t' || *nextLine == ' ')
	  nextLine = text_find_next_line(nextLine);

	/* Copy the current line into our own buffer. */

	if (!strncasecmp(currLine, "From:", 5) ||
	    !strncasecmp(currLine, "To:", 3) ||
	    !strncasecmp(currLine, "Cc:", 3) ||
	    !strncasecmp(currLine, "Subject:", 8) ||
	    !strncasecmp(currLine, "Date:", 5) ||
	    !strncasecmp(currLine, "MIME-Version:", 13) ||
	    !strncasecmp(currLine, "Content-Type:", 13) ||
	    !strncasecmp(currLine, "Content-Transfer-Encoding:", 26) ||
	    !strncasecmp(currLine, "In-Reply-To:", 12) ||
	    !strncasecmp(currLine, "References:", 11) ||
	    !strncasecmp(currLine, "Message-Id:", 11) ||
	    !strncasecmp(currLine, "Received:", 9)) {
	    len = nextLine - currLine;
	    memmove(dst, currLine, len);
	    dst += len;
	    debug((DEBUG_HERMES, 9, "Copied line."));
	}
    }

    /* Add a Reply-To: field. */

    if (ListConfig->reply_to == NULL)
      len = sprintf(dst, "Reply-To: %s@%s\n", listname, ListConfig->fqdn);
    else if (!strcasecmp(ListConfig->reply_to, "none")) {
	if (MailStruct->Reply_To != NULL) {

	    /* Copy Reply-To: line from original header. */

	    for(len = 0, currLine = MailStruct->Header;
		*currLine != '\0';
		currLine = nextLine) {

		nextLine = text_find_next_line(currLine);
		while (*nextLine == '\t' || *nextLine == ' ')
		  nextLine = text_find_next_line(nextLine);

		if (!strncasecmp(currLine, "Reply-To:", 9)) {
		    len = nextLine - currLine;
		    memmove(dst, currLine, len);
		}
	    }

	}
	else
	  len = 0;
    }
    else {
	len = sprintf(dst, "Reply-To: %s\n", ListConfig->reply_to);
    }
    dst += len;

    /* Add a Sender: field. */

    len = sprintf(dst, "Sender: %s\n", owner);
    dst += len;

    /* Add a Precedence: field. */

    len = sprintf(dst, "Precedence: list\n");
    dst += len;
    *dst = '\0';

    /* Add the signature if there is one. */

    buffer = text_easy_sprintf("lists/%s/signature", listname);
    debug((DEBUG_HERMES, 6, "Checking whether \"%s\" exists.", buffer));
    if (stat(buffer, &sb) == 0) {
	debug((DEBUG_HERMES, 3, "Appending signature \"%s\".", buffer));
	buffer = loadfile(buffer);
	if (buffer == NULL) {
	    syslog(LOG_ERR, "Failed reading the signature file for list \"%s\".", listname);
	    exit(1);
	}
	MailStruct->ListSignature = buffer;
	debug((DEBUG_HERMES, 7, "Signature is: \"%s\".", buffer));
    }
    else
      debug((DEBUG_HERMES, 3, "No signature file \"%s\".", buffer));

    /* No more modifications will be made. Now copy the posting
       headers into the structure instead of the original ones. */

    MailStruct->Header = PostingHeaders;

    /* Apply the posting filter. */

    if (ListConfig->postingfilter != NULL) {
	debug((DEBUG_HERMES, 3, "Applying posting filter for list \"%s\".", listname));
	rc = MailFilter(MailStruct, ListConfig->postingfilter);
	if (rc != 0) {
	    syslog(LOG_ERR, "Postingfilter \"%s\" returned error %d while processing posting " \
	    "for list \"%s\".", ListConfig->postingfilter, rc, listname);
	    exit(1);
	}
	debug((DEBUG_HERMES, 6, "Filter was successful: returncode = %d.", rc));
    }

    /* Deliver the article to all recipients. */

    rc = ListMail(envelope, listname, MailStruct);
    if (rc != 0) {
	syslog(LOG_ERR, "The attempt to deliver the article to the subscribers failed.");
	exit(1);
    }

    syslog(LOG_INFO, "Posted article from \"%s\" to list \"%s\" successfully.",
	MailStruct->From, listname);

    /* Archive the article. */

    ArchiveMail(MailStruct, listname);

    return 0;
}