/*
 * Check for new and old mail.
 *      Brian Katzung  15 July 1986
 */

#include <stdio.h>
#include <pwd.h>

char	*getenv();

char	*spool[] = {
	"/usr/spool/mail",
	"/usr/mail"
};
#define	NSPOOL	(sizeof(spool) / sizeof(spool[0]))

main (ac, av)
char    **av;
{
        struct  passwd  *pwp, *getpwuid();
        char    file[256];
        char    line[1024];
        int     num;
        register char   *cp;
        short   hasmail;
        short   newmail;
        short   unread;
        short   sawfrom;
        FILE    *mfd;

	/*
	 * Look for a mail spool directory.
	 */
	*file = '\0';
	for (num = 0; num < NSPOOL && access(spool[num], 5); ++num)
		;
	if (num < NSPOOL)
		sprintf(file, "%s/", spool[num]);

        /*
         * Default is current user's mail file.
         */
        if (ac < 2)
        {
		/* Use $MAIL if set */
		if ((cp = getenv("MAIL")) && (*cp != '\0'))
			strcpy(file, cp);

		/* Otherwise, use spool directory and login name */
		else
		{
			if ((pwp = getpwuid(getuid())) == NULL)
			{
				fputs("mailchk:  Can't get passwd entry.\n",
				  stderr);
				exit(1);
			}

			strcat(file, pwp->pw_name);
		}
        }

        /*
         * If argument present, try a user's mail file or a file name.
         */
        else if (strchr(av[1], '/'))
                strcpy(file, av[1]);
        else
                strcat(file, av[1]);

        if (access(file, 0))
                exit(0);

        if ((mfd = fopen(file, "r")) == NULL)
        {
                perror(file);
                exit(1);
        }

        hasmail = 0;
        newmail = 0;
        unread = 0;
        sawfrom = 0;

        while (fgets(line, sizeof(line), mfd) != NULL)
        {
                /*
                 * Look for Unix From lines.
                 */
		if (strncmp(line, "From ", 5) == 0)
                {
                        ++hasmail;
                        ++sawfrom;
                }

                /*
                 * See if Mail has ever noticed message.
                 */
                if (sawfrom && strncmp(line, "Status: ", 8) == 0)
                {
                        for (cp = &line[8]; *cp && *cp != 'R'; ++cp);
                        if (*cp != 'R')
                                ++unread;

                        sawfrom = 0;
                }

                /*
                 * Check for new messages.
                 */
                if (sawfrom && *line == '\n')
                {
                        ++newmail;
                        sawfrom = 0;
                }
        }

        if (hasmail)
        {
                if (ac < 2)
                        printf("You have");
                else
                        printf("%s has", av[1]);
                printf(" mail (%d total, %d new, %d unread).\n",
                        hasmail, newmail, newmail + unread);
        }
}