/*
 * Prompting and other messages.
 * There are three flavors of prompts, SHORT, MEDIUM and LONG,
 * selected by the -m/-M options.
 * A prompt is either a colon or a message composed of various
 * pieces, such as the name of the file being viewed, the percentage
 * into the file, etc.
 */

#include "less.h"

#include "position.h"

extern int pr_type;
extern int ispipe;
extern int hit_eof;
extern int new_file;
extern int sc_width;
extern char current_file[];
extern int ac;
extern char **av;
extern int curr_ac;

/* Prototypes for functions defined in prompt.c */

static void setmp __PROTO((void));
static void ap_filename __PROTO((void));
static void ap_of __PROTO((void));
static void ap_byte __PROTO((void));
static void ap_percent __PROTO((int must_print));
static void ap_eof __PROTO((void));
static char *pr_expand __PROTO((char *proto,
                                int maxwidth));


/*
 * Prototypes for the three flavors of prompts.
 * These strings are expanded by pr_expand().
 */
char *prproto[] = {
        "fo",           /* PR_SHORT */
        "foP",          /* PR_MEDIUM */
        "Fobp"          /* PR_LONG */
};

static char message[200];
static char *mp;

#ifdef __STDC__
static void setmp (void)
#else
        static void
setmp()
#endif
{
        mp = message + strlen(message);
}

/*
 * Append the name of the current file (to the message buffer).
 */
#ifdef __STDC__
static void ap_filename (void)
#else
        static void
ap_filename()
#endif
{
        if (ispipe)
                return;
        strtcpy(mp, current_file, &message[sizeof(message)] - mp);
        setmp();
}

/*
 * Append the "file N of M" message.
 */
#ifdef __STDC__
static void ap_of (void)
#else
        static void
ap_of()
#endif
{
        if (ac <= 1)
                return;
        sprintf(mp, " (file %ld of %ld)", curr_ac+1, ac);
        setmp();
}

/*
 * Append the byte offset into the current file.
 */
#ifdef __STDC__
static void ap_byte (void)
#else
        static void
ap_byte()
#endif
{
        POSITION pos, len;

        pos = position(BOTTOM_PLUS_ONE);
        if (pos == NULL_POSITION)
                pos = ch_length();
        if (pos != NULL_POSITION)
        {
                sprintf(mp, " byte %ld", (long)pos);
                setmp();
                len = ch_length();
                if (len > 0)
                {
                        sprintf(mp, "/%ld", (long)len);
                        setmp();
                }
        }
}

/*
 * Append the percentage into the current file.
 * If we cannot find the percentage and must_print is true,
 * use the byte offset.
 */
#ifdef __STDC__
static void ap_percent (int must_print)
#else
        static void
ap_percent(must_print)
#endif
{
        POSITION pos,len;

        pos = position(BOTTOM_PLUS_ONE);
        len = ch_length();
        if (len > 0 && pos != NULL_POSITION)
        {
                sprintf(mp, " (%ld%%)", (100 * (long)pos) / len);
                setmp();
        } else if (must_print)
                ap_byte();
}

/*
 * Append the end-of-file message.
 */
#ifdef __STDC__
static void ap_eof (void)
#else
        static void
ap_eof()
#endif
{
        strcpy(mp, " (END)");
        setmp();
        if (curr_ac + 1 < ac)
        {
                sprintf(mp, " - Next: %s", av[curr_ac+1]);
                setmp();
        }
}

/*
 * Construct a message based on a prototype string.
 */
#ifdef __STDC__
static char *pr_expand (char *proto, int maxwidth)
#else
        static char *
pr_expand(proto, maxwidth)
        char *proto;
        int maxwidth;
#endif
{
        register char *p;

        mp = message;

        for (p = proto;  *p != '\0';  p++)
        {
                if (maxwidth > 0 && mp >= message + maxwidth)
                {
                        /*
                         * Truncate to the screen width.
                         * {{ This isn't very nice. }}
                         */
#ifndef AMIGA
                        mp = message + maxwidth;
#endif
                        break;
                }
                switch (*p)
                {
                case 'f':
                        if (new_file)
                                ap_filename();
                        break;
                case 'F':
                        ap_filename();
                        break;
                case 'o':
                        if (new_file)
                                ap_of();
                        break;
                case 'O':
                        ap_of();
                        break;
                case 'b':
                        ap_byte();
                        break;
                case 'p':
                        if (!hit_eof)
                                ap_percent(0);
                        break;
                case 'P':
                        if (!hit_eof)
                                ap_percent(1);
                        break;
                case '<':
                        while (*++p != '>')
                        {
                                if (*p == '\0')
                                {
                                        p--;
                                        break;
                                }
                                *mp++ = *p;
                        }
                        break;
                default:
                        *mp++ = *p;
                        break;
                }
        }
        if (hit_eof)
                ap_eof();

#ifndef AMIGA
        new_file = 0;
#endif
        if (mp == message)
                return (NULL);
        *mp = '\0';
        return (message);
}

/*
 * Return a message suitable for printing by the "=" command.
 */
#ifdef __STDC__
char *eq_message (void)
#else
        public char *
eq_message()
#endif
{
        return (pr_expand("FObp", 0));
}

/*
 * Return a prompt.
 * This depends on the prompt type (SHORT, MEDIUM, LONG), etc.
 * If we can't come up with an appropriate prompt, return NULL
 * and the caller will prompt with a colon.
 */
#ifdef __STDC__
char *pr_string (void)
#else
        public char *
pr_string()
#endif
{

#ifdef AMIGA
        char *result, *bestresult;
        int i, len, bestlen;

        /* Try to make the prompt fit the window */

        bestlen = -1;
        for ( i = 0; i<3; i++ )
        {
            result = pr_expand(prproto[i], sc_width - 2);
            len = (result? strlen(result): 0);
            if ( i == pr_type && len < sc_width - 2 )
            {
                bestresult = result;
                bestlen = len;
                break;
            }
            if ( len < sc_width - 2 && len > bestlen )
            {
                bestresult = result;
                bestlen = len;
            }
        }
        new_file = 0;
        if ( bestlen >= 0 )
            return bestresult;
        else
            return NULL;
#else
        return (pr_expand(prproto[pr_type], sc_width-2));
#endif
}