/**                     from.c                  **/

/** print out whom each message is from in the pending folder or specified
    one, including a subject line if available..

    Added PREFER_UUCP knowledge 6/86
    Added "-n" flag, 9/86
    Added "-v" flag, 3/87

    (C) Copyright 1986 Dave Taylor
**/

#include <stdio.h>
#include "defs.h"

static char ident[] = { WHAT_STRING };

#define LINEFEED        (char) 10

#define metachar(c)     (c == '=' || c == '+' || c == '%')

FILE *mailfile;

char *expand_define();
int   number = 0,       /* should we number the messages?? */
      verbose = 0;      /* and should we prepend a header? */

void read_ctl();

main(argc, argv)
int argc;
char *argv[];
{
        char infile[LONG_SLEN], username[SLEN], c;
        int  multiple_files = 0, output_files = 0;

        extern int opt_index;

        read_ctl();

        while ((c = get_options(argc, argv, "nv")) > 0)
          switch (c) {
            case 'n': number++;         break;
            case 'v': verbose++;        break;
          }

        if (c == -1) {
          printf("Usage: %s [-n] [-v] {filename | username}\n", argv[0]);
          exit(1);
        }

        if (opt_index == argc) {
          strcpy(username, getlogin());
          if (strlen(username) == 0)
            cuserid(username);
          sprintf(infile,"%s%s",mailhome, username);
          opt_index -= 1;       /* ensure one pass through loop */
        }

        multiple_files = (argc - opt_index > 1);

        while (opt_index < argc) {

          if (multiple_files) {
            strcpy(infile, argv[opt_index]);
            printf("%s%s: \n", output_files++ > 0 ? "\n":"", infile);
          }
          else if (infile[0] == '\0')
            strcpy(infile, argv[opt_index]);

          if (metachar(infile[0])) {
            if (expand(infile) == 0) {
               fprintf(stderr, "%s: couldn't expand filename %s!\n",
                       argv[0], infile);
               exit(1);
            }
          }

          if ((mailfile = fopen(infile,"r")) == NULL) {
            if (opt_index+1 == argc)
              printf("No mail\n");
            else {
              if (infile[0] == '/')
                printf("Couldn't open folder \"%s\".\n", infile);
              else {
                sprintf(infile,"%s%s", mailhome, argv[opt_index]);
                if ((mailfile = fopen(infile,"r")) == NULL)
                  printf("Couldn't open folders \"%s\" or \"%s\".\n",
                         argv[opt_index], infile);
                else if (read_headers()==0)
                  printf("No messages in that folder!\n");
               }
            }
          }
          else
            if (read_headers(opt_index+1 == argc)==0)
              if (opt_index+1 == argc)
                printf("No mail\n");
              else
                printf("No messages in that folder!\n");

          opt_index++;
        }
        exit(0);
}

int
read_headers(user_mailbox)
int user_mailbox;
{
        /** Read the headers, output as found.  User-Mailbox is to guarantee
            that we get a reasonably sensible message from the '-v' option
         **/

        char buffer[LONG_SLEN], from_whom[SLEN], subject[SLEN];
        register int subj = 0, in_header = 1, count = 0;

        while (fgets(buffer, LONG_SLEN, mailfile) != NULL) {
          if (first_word(buffer,"From ")) {
            if (real_from(buffer, from_whom)) {
              subj = 0;
              in_header = 1;
            }
          }
          else if (in_header) {
            if (first_word(buffer,">From"))
              forwarded(buffer, from_whom); /* return address */
            else if (first_word(buffer,"Subject:") ||
                     first_word(buffer,"Re:")) {
              if (! subj++) {
                remove_first_word(buffer);
                strcpy(subject, buffer);
              }
            }
            else if (first_word(buffer,"From:"))
              parse_arpa_from(buffer, from_whom);
            else if (buffer[0] == LINEFEED) {
              if (verbose && count == 0)
                printf("%s contains the following messages:\n\n",
                        user_mailbox?"Your mailbox" : "Folder");
              in_header = 0;    /* in body of message! */
              show_header(count+1, from_whom, subject);
              from_whom[0] = 0;
              subject[0] = 0;
              count++;
            }
          }
        }
        return(count);
}

int
real_from(buffer, who)
char *buffer, *who;
{
        /***** returns true iff 's' has the seven 'from' fields,
               initializing the who to the sender *****/

        char junk[80];

        junk[0] = '\0';
        sscanf(buffer, "%*s %s %*s %*s %*s %*s %s",
                    who, junk);
        return(junk[0] != '\0');
}

forwarded(buffer, who)
char *buffer, *who;
{
        /** change 'from' and date fields to reflect the ORIGINATOR of
            the message by iteratively parsing the >From fields... **/

        char machine[80], buff[80];

        machine[0] = '\0';
        sscanf(buffer, "%*s %s %*s %*s %*s %*s %*s %*s %*s %s",
                    who, machine);

        if (machine[0] == '\0') /* try for srm address */
          sscanf(buffer, "%*s %s %*s %*s %*s %*s %*s %*s %s",
                    who, machine);

        if (machine[0] == '\0')
          sprintf(buff,"anonymous");
        else
          sprintf(buff,"%s!%s", machine, who);

        strncpy(who, buff, 80);
}

remove_first_word(string)
char *string;
{       /** removes first word of string, ie up to first non-white space
            following a white space! **/

        register int loc;

        for (loc = 0; string[loc] != ' ' && string[loc] != '\0'; loc++)
            ;

        while (string[loc] == ' ' || string[loc] == '\t')
          loc++;

        move_left(string, loc);
}

move_left(string, chars)
char string[];
int  chars;
{
        /** moves string chars characters to the left DESTRUCTIVELY **/

        register int i;

        chars--; /* index starting at zero! */

        for (i=chars; string[i] != '\0' && string[i] != '\n'; i++)
          string[i-chars] = string[i];

        string[i-chars] = '\0';
}

show_header(count, from, subject)
int  count;
char *from, *subject;
{
        /** output header in clean format, including abbreviation
            of return address if more than one machine name is
            contained within it! **/

        char buffer[SLEN];
        int  loc, i=0, exc=0;

#ifdef PREFER_UUCP
        char *p;

        if (chloc(from,'!') != -1 && chloc(from,'@') > 0) {
          for (p=from;*p != '@'; p++) ;
          *p = '\0';
        }
#endif

        loc = strlen(from);

        while (exc < 2 && loc > 0)
          if (from[--loc] == '!')
            exc++;

        if (exc == 2) { /* lots of machine names!  Get last one */
          loc++;
          while (loc < strlen(from) && loc < SLEN)
            buffer[i++] = from[loc++];
          buffer[i] = '\0';
          if (number)
            printf("%3d: %-20s  %s\n", count, buffer, subject);
          else
            printf("%-20s  %s\n", buffer, subject);
        }
        else
          if (number)
            printf("%3d: %-20s  %s\n", count, from, subject);
          else
            printf("%-20s  %s\n", from, subject);
}

parse_arpa_from(buffer, newfrom)
char *buffer, *newfrom;
{
        /** try to parse the 'From:' line given... It can be in one of
            two formats:
                From: Dave Taylor <hpcnou!dat>
            or  From: hpcnou!dat (Dave Taylor)
            Change 'newfrom' ONLY if sucessfully parsed this entry and
            the resulting name is non-null!
        **/

        char temp_buffer[SLEN], *temp;
        register int i, j = 0;

        temp = (char *) temp_buffer;
        temp[0] = '\0';

        no_ret(buffer);         /* blow away '\n' char! */

        if (lastch(buffer) == '>') {
          for (i=strlen("From: "); buffer[i] != '\0' && buffer[i] != '<' &&
               buffer[i] != '('; i++)
            temp[j++] = buffer[i];
          temp[j] = '\0';
        }
        else if (lastch(buffer) == ')') {
          for (i=strlen(buffer)-2; buffer[i] != '\0' && buffer[i] != '(' &&
               buffer[i] != '<'; i--)
            temp[j++] = buffer[i];
          temp[j] = '\0';
          reverse(temp);
        }

        if (strlen(temp) > 0) {         /* mess with buffer... */

          /* remove leading spaces... */

          while (whitespace(temp[0]))
            temp = (char *) (temp + 1);         /* increment address! */

          /* remove trailing spaces... */

          i = strlen(temp) - 1;

          while (whitespace(temp[i]))
           temp[i--] = '\0';

          /* if anything is left, let's change 'from' value! */

          if (strlen(temp) > 0)
            strcpy(newfrom, temp);
        }
}

reverse(string)
char *string;
{
        /** reverse string... pretty trivial routine, actually! **/

        char buffer[SLEN];
        register int i, j = 0;

        for (i = strlen(string)-1; i >= 0; i--)
          buffer[j++] = string[i];

        buffer[j] = '\0';

        strcpy(string, buffer);
}