/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright (c) 1989, 2010, Oracle and/or its affiliates. All rights reserved.
 */

/*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/*        All Rights Reserved   */

#include "mail.h"

#define MAXHDRSIZE      100     /* Maximum length of header line */
#define MAXUNAME        20      /* Maximum length of user name */

/*
 *      display headers, indicating current and status
 *
 *      current is the displacement into the mailfile of the
 *      current letter
 *
 *      all indicates how many headers should be shown.
 *              0       ->      show window +/-6 around current
 *              1       ->      show all messages
 *              2       ->      show deleted messages
 *
 *      Only 100 characters of the From (first) header line will
 *      be read in.  This line is assumed to be in the following
 *      format:
 *              From <sender address> <date>
 *      where
 *              <sender address> is either a UUCP-style (sysa!sysb!user)
 *              or domain-style address (user@host).
 *
 *      If the sender address contains a UUCP-style address, then
 *      the user name displayed is made up of the characters following
 *      the final '!' in the sender address, otherwise the sender
 *      address is considered to be the user name.
 *
 *      The maximum number of characters of a user name displayed
 *      is 19.
 *
 */
int
gethead(int current, int all)
{

        int     displayed = 0;
        FILE    *file;
        char    *hold;
        char    holdval[MAXHDRSIZE];
        char    *wline;
        char    wlineval[MAXHDRSIZE];
        int     ln;
        char    mark;
        int     rc, size, start, stop, ix;
        char    userval[MAXUNAME];
        char    *uucpptr;
        int     uucpstart;
        int     unamechars = MAXUNAME - 1;
        int     sender_size;

        hold = holdval;
        wline = wlineval;

        printf("%d letters found in %s, %d scheduled for deletion, "
            "%d newly arrived\n", nlet, mailfile, changed, nlet - onlet);

        if (all == 2 && !changed)
                return (0);

        file = doopen(lettmp, "r", E_TMP);
        if (!flgr) {
                stop = current - 6;
                if (stop < -1) stop = -1;
                start = current + 5;
                if (start > nlet - 1) start = nlet - 1;
                if (all) {
                        start = nlet -1;
                        stop = -1;
                }
        } else {
                stop = current + 6;
                if (stop > nlet) stop = nlet;
                start = current - 5;
                if (start < 0) start = 0;
                if (all) {
                        start = 0;
                        stop = nlet;
                }
        }
        for (ln = start; ln != stop; ln = flgr ? ln + 1 : ln - 1) {
                size = let[ln+1].adr - let[ln].adr;
                if ((rc = fseek(file, let[ln].adr, 0)) != 0) {
                        errmsg(E_FILE, "Cannot seek header");
                        fclose(file);
                        return (1);
                }
                if (fgets(wline, MAXHDRSIZE, file) == NULL) {
                        errmsg(E_FILE, "Cannot read header");
                        fclose(file);
                        return (1);
                }
                if ((rc = strncmp(wline, header[H_FROM].tag, 5)) != SAME) {
                        errmsg(E_FILE, "Invalid header encountered");
                        fclose(file);
                        return (1);
                }

                /* skip past trailing white space after header tag */
                for (rc = 5; wline[rc] == ' ' || wline[rc] == '\t'; ++rc)
                        ;
                (void) strlcpy(hold, wline + rc, MAXHDRSIZE);
                fgets(wline, MAXHDRSIZE, file);

                while (((rc = strncmp(wline,
                    header[H_FROM1].tag, 6)) == SAME) &&
                    (substr(wline, "remote from ") != -1)) {
                        (void) strlcpy(hold, wline + 6, MAXHDRSIZE);
                        fgets(wline, MAXHDRSIZE, file);
                }


                /*
                 * If UUCP-style sender address, then read past
                 * last "!" to get the start of the user name.
                 */
                sender_size = strcspn(hold, " \t");
                uucpstart = 0;
                if ((uucpptr = strrchr(hold, '!')) != NULL) {
                        uucpstart = uucpptr - hold + 1;
                        if (uucpstart > sender_size) {
                                uucpstart = 0;
                        }
                }

                /* Get the user name out of the sender address. */
                for (ix = 0, rc = uucpstart; ix < unamechars &&
                    hold[rc] != ' ' && hold[rc] != '\t' &&
                    rc < sender_size; ++rc) {
                        userval[ix++] = hold[rc];
                }
                if ((ix > 0) && (userval[ix - 1] == '\n')) {
                        userval[ix - 1] = '\0';
                } else {
                        userval[ix] = '\0';
                }

                /*
                 * Skip past the rest of the sender address, and
                 * delimiting white space.
                 */
                for (; hold[rc] != '\0' && hold[rc] != ' ' &&
                    hold[rc] != '\t'; ++rc)
                        ;
                for (; hold[rc] == ' ' || hold[rc] == '\t'; ++rc)
                        ;

                /* Get the date information. */
                (void) strlcpy(wline, hold + rc, MAXHDRSIZE);
                for (rc = 0; wline[rc] != '\0' && wline[rc] != '\n'; ++rc)
                        ;
                wline[rc] = '\0';

                if (!flgh && current == ln) mark = '>';
                else mark = ' ';

                if (all == 2) {
                        if (displayed >= changed) {
                                fclose(file);
                                return (0);
                        }
                        if (let[ln].change == ' ') continue;
                }

                printf("%c %3d  %c  %-5d  %-10s  %s\n", mark, ln + 1,
                    let[ln].change, size, userval, wline);
                displayed++;
        }
        fclose(file);
        return (0);
}

void
tmperr(void)
{
        fclose(tmpf);
        errmsg(E_TMP, "");
}

/*
 *      Write a string out to tmp file, with error checking.
 *      Return 1 on success, else 0
 */
int
wtmpf(char *str, int length)
{
        if (fwrite(str, 1, length, tmpf) != length) {
                tmperr();
                return (0);
        }
        return (1);
}

/*
 *      Read a line from stdin, assign it to line and
 *      return number of bytes in length
 */
int
getaline(char *ptr2line, int max, FILE *f)
{
        int     i, ch;
        for (i = 0; i < max-1 && (ch = getc(f)) != EOF; )
                if ((ptr2line[i++] = ch) == '\n') break;
        ptr2line[i] = '\0';
        return (i);
}

/*
 *      Make temporary file for letter
 */
void
mktmp(void)
{
        static char tmpl[] = "/var/tmp/mailXXXXXX";
        int fd = mkstemp(lettmp = tmpl);

        if (fd < 0 || (tmpf = fdopen(fd, "w+")) == NULL) {
                fprintf(stderr,
                    "%s: Can't open '%s', type: w+\n", program, lettmp);
                done(0);
        }
}

/*
 * Get a number from user's reply,
 * return its value or zero if none present, -1 on error
 */
int
getnumbr(char *s)
{
        int     k = 0;

        while (*s == ' ' || *s == '\t') s++;

        if (*s != '\0') {
                if ((k = atoi(s)) != 0)
                        if (!validmsg(k))
                                return (-1);

                for (; *s >= '0' && *s <= '9'; ) s++;
                if (*s != '\0' && *s != '\n') {
                        printf("Illegal numeric\n");
                        return (-1);
                }
                return (k);
        }
        return (0);
}

/*
 *      If valid msgnum return 1,
 *              else print message and return 0
 */
int
validmsg(int i)
{
        if ((i < 0) || (i > nlet)) {
                printf("No such message\n");
                return (0);
        }
        return (1);
}

/*
 *      Set letter to passed status, and adjust changed as necessary
 */
void
setletr(int letter, int status)
{
        if (status == ' ') {
                if (let[letter].change != ' ')
                        if (changed) changed--;
        } else {
                if (let[letter].change == ' ') changed++;
        }
        let[letter].change = status;
}