#include "elm_defs.h"
#include "elm_globals.h"
#include "mime.h"
#include "sndhdrs.h"
#include "s_elm.h"
#include <assert.h>


extern char *format_long();
extern char *strip_commas();

static int add_mailheaders P_((FILE *));
static int expand_backquote P_((FILE *, const char *));


PUBLIC SEND_HEADER *sndhdr_new()
{
    SEND_HEADER *shdr;
    char *p;

    shdr = (SEND_HEADER *) safe_malloc(sizeof(SEND_HEADER));

    shdr->subject[0] = '\0';

    shdr->to[0] = '\0';
    shdr->cc[0] = '\0';
    shdr->bcc[0] = '\0';

    shdr->expanded_to[0] = '\0';
    shdr->expanded_cc[0] = '\0';
    shdr->expanded_bcc[0] = '\0';

    if ((p = getenv("REPLYTO")) != NULL) {
	(void) strfcpy(shdr->reply_to, p, sizeof(shdr->reply_to));
	(void) build_address(strip_commas(shdr->reply_to),
		    shdr->expanded_reply_to);
    } else {
	shdr->reply_to[0] = '\0';
	shdr->expanded_reply_to[0] = '\0';
    }

    shdr->in_reply_to[0] = '\0';
    shdr->precedence[0] = '\0';
    shdr->priority[0] = '\0';
    shdr->action[0] = '\0';
    shdr->expires[0] = '\0';
    shdr->expires_days[0] = '\0';
    shdr->user_defined_header[0] = '\0';

    return shdr;
}


PUBLIC void sndhdr_destroy(shdr)
SEND_HEADER *shdr;
{
	free((malloc_t)shdr);
}


static void write_header_line(fp, hdrname, hdrvalue)
FILE *fp;
const char *hdrname, *hdrvalue;
{
    fputs(hdrname, fp);
    putc(' ', fp);
    fputs(hdrvalue, fp);
    putc('\n', fp);
}


#ifndef DONT_ADD_FROM
static char *outbound_from_name(buf)
char *buf;
{
#ifdef MMDF
    if (streq(submitmail, mailer)) {
	sprintf(buf, "\"%s\" <%s>", user_fullname, user_name);
	return buf;
    }
#endif
#ifdef INTERNET
# ifdef USE_DOMAIN
    sprintf(buf, "\"%s\" <%s@%s>", user_fullname, user_name, host_fullname);
# else
    sprintf(buf, "\"%s\" <%s@%s>", user_fullname, user_name, host_name);
# endif
#else /* !INTERNET */
    sprintf(buf, "\"%s\" <%s!%s>", user_fullname, host_name, user_name);
#endif /* !INTERNET */
    return buf;
}
#endif /* !DONT_ADD_FROM */



PUBLIC int sndhdr_output(fp, shdr, is_form, is_copy)
FILE *fp;
const SEND_HEADER *shdr;
int is_form, is_copy;
{
    /** Write mail headers to stream "fp".
	Added the ability to have backquoted stuff in the users
	    .elmheaders file!
	If copy is TRUE, then treat this as the saved copy of outbound
	    mail.
    **/

    char buffer[SLEN];
    int err;

    /** Subject moved to top of headers for mail because the
	pure System V.3 mailer, in its infinite wisdom, now
	assumes that anything the user sends is part of the
	message body unless either:
	    1. the "-s" flag is used (although it doesn't seem
	       to be supported on all implementations?? )
	    2. the first line is "Subject:".  If so, then it'll
	       read until a blank line and assume all are meant
	       to be headers.
	So the gory solution here is to move the Subject: line
	up to the top.  I assume it won't break anyone elses program
	or anything anyway (besides, RFC-822 specifies that the *order*
	of headers is irrelevant).  Gahhhhh....
    **/

    write_header_line(fp, "Subject:", shdr->subject);
    write_header_line(fp, "To:",
		format_long(shdr->expanded_to, sizeof("To: ")-1));
    write_header_line(fp, "Date:", get_arpa_date());
#ifndef DONT_ADD_FROM
    write_header_line(fp, "From:", outbound_from_name(buffer));
#endif
    if (*shdr->cc) {
	write_header_line(fp, "Cc:",
		    format_long(shdr->expanded_cc, sizeof("Cc: ")-1));
    }
    if (is_copy && *shdr->bcc) {
	write_header_line(fp, "Bcc:",
		    format_long(shdr->expanded_bcc, sizeof("Bcc: ")-1));
    }
    if (*shdr->action)
	write_header_line(fp, "Action:", shdr->action);
    if (*shdr->priority)
	write_header_line(fp, "Priority:", shdr->priority);
    if (*shdr->precedence)
	write_header_line(fp, "Precedence:", shdr->precedence);
    if (*shdr->expires)
	write_header_line(fp, "Expires:", shdr->expires);
    if (*shdr->expanded_reply_to)
	write_header_line(fp, "Reply-To:", shdr->expanded_reply_to);
    if (*shdr->in_reply_to)
	write_header_line(fp, "In-Reply-To:", shdr->in_reply_to);
    if (*shdr->user_defined_header) {
	fputs(shdr->user_defined_header, fp);
	putc('\n', fp);
    }
    if (add_mailheaders(fp) < 0)
	return -1;
#ifndef NO_XHEADER
    fprintf(fp, "X-Mailer: ELM [version %s]\n", version_buff);
#endif /* !NO_XHEADER */

    if (is_form)
	fputs("Content-Type: mailform\n", fp);

    return 0;
}


PUBLIC void generate_in_reply_to(shdr, msg)
SEND_HEADER *shdr;
int msg;
{
    char from_buf[SLEN], date_buf[SLEN], *q;
    struct header_rec *hdr = curr_folder.headers[msg];
    extern char *elm_date_str();

    assert(msg >= 0 && msg < curr_folder.num_mssgs);

    if (strchr(hdr->from, '!') != NULL)
	tail_of(hdr->from, from_buf, (char *)NULL);
    else
	strcpy(from_buf, hdr->from);

    /* don't quote already-quoted name */
    q = (from_buf[0] == '"' ? "" : "\"");

    sprintf(shdr->in_reply_to, "%s from %s%s%s at %s",
	(*hdr->messageid ? hdr->messageid : "<no.id>"),
	q, from_buf, q,
	elm_date_str(date_buf, hdr, TRUE));
}


/*
 * Add contents of ~/.elm/elmheaders file to output stream.
 * Allows `backquote` expansion to do fortune(6) type things. (*shudder*)
 */
static int add_mailheaders(fp_mssg)
FILE *fp_mssg;
{
    char buf[SLEN], *s, *beg_cmd, *end_cmd;
    int rc;
    FILE *fp_mhdrs;

    sprintf(buf, "%s/%s", user_home, mailheaders);
    if ((fp_mhdrs = fopen(buf, "r")) == NULL)
	return 0;

    rc = -1;
    while (fgets(buf, sizeof(buf), fp_mhdrs) != NULL) {

	trim_trailing_spaces(buf);
	if (buf[0] == '#' || buf[0] == '\0')
	    continue;

	for (s = buf ; s != NULL && *s != '\0' ; ++s) {
	    if (*s != '`') {
		putc(*s, fp_mssg);
		continue;
	    }
	    beg_cmd = s+1;
	    if ((end_cmd = strchr(beg_cmd, '`')) != NULL)
		*end_cmd++ = '\0';
	    if (expand_backquote(fp_mssg, beg_cmd) < 0)
		goto done;
	    s = end_cmd;
	}

	putc('\n', fp_mssg);

    }

    rc = 0;

done:
    if (fp_mhdrs != NULL)
	(void) fclose(fp_mhdrs);
    return rc;
}


/*
 * Execute command dump output to stream.  Blank lines are discarded.
 * Multiple lines are tab indented to allow header continuations.
 */
static int expand_backquote(fp_mssg, cmd)
FILE *fp_mssg;
const char *cmd;
{
    FILE *fp_expan;
    char fname[SLEN], buf[SLEN];
    int rc, first_line;

    rc = -1;
    sprintf(fname, "%s%s%d", temp_dir, temp_print, getpid());
    sprintf(buf, "%s > %s", cmd, fname);

    if (system_call(buf, 0) != 0 || (fp_expan = fopen(fname, "r")) == NULL) {
	error1(catgets(elm_msg_cat, ElmSet, ElmBackquoteCmdFailed,
		"Backquoted command \"%s\" in elmheaders failed."), cmd);
	goto done;
    }

    first_line = TRUE;
    while (fgets(buf, sizeof(buf), fp_expan) != NULL) {
	trim_trailing_spaces(buf);
	if (buf[0] != '\0') {
	    if (!first_line)
		fputs("\n\t", fp_mssg);
	    first_line = FALSE;
	    fputs(buf, fp_mssg);
	}
    }

    (void) fclose(fp_expan);
    rc = 0;

done:
    (void) unlink(fname);
    return rc;
}