/* bind.c -- implements bind.h */
#include "bind.h"

/*  bind.c
 *
 *  This file is for functions having to do with key bindings,
 *  descriptions, help commands and startup file.
 *
 *  Written 11-feb-86 by Daniel Lawrence
 *  Modified by Petri Kutvonen
 */

#include <stdio.h>
#include <string.h>

#include "estruct.h"
#include "bindable.h"
#include "buffer.h"
#include "display.h"
#include "ebind.h"
#include "exec.h"
#include "file.h"
#include "flook.h"
#include "input.h"
#include "line.h"
#include "names.h"
#include "window.h"


#if APROP
static int buildlist( char *mstring) ;
static int strinc( char *source, char *sub) ;
#endif

static void cmdstr( int c, char *seq) ;
static unsigned int getckey( int mflag) ;
static unsigned int stock( char *keyname) ;
static int unbindchar( unsigned c) ;
static char *getfname( fn_t) ;


int help(int f, int n)
{               /* give me some help!!!!
                   bring up a fake buffer and read the help file
                   into it with view mode                 */
    struct window *wp;  /* scaning pointer to windows */
    struct buffer *bp;  /* buffer pointer to help */
    char *fname = NULL; /* ptr to file returned by flook() */

    /* first check if we are already here */
    bp = bfind( hlpfname, FALSE, BFINVS);

    if (bp == NULL) {
        fname = flook( hlpfname, FALSE);
        if (fname == NULL) {
            mlwrite("(Help file is not online)");
            return FALSE;
        }
    }

    /* split the current window to make room for the help stuff */
    if (splitwind(FALSE, 1) == FALSE)
        return FALSE;

    if (bp == NULL) {
        /* and read the stuff in */
        if (getfile(fname, FALSE) == FALSE)
            return FALSE;
    } else
        swbuffer(bp);

    /* make this window in VIEW mode, update all mode lines */
    curwp->w_bufp->b_mode |= MDVIEW;
    curwp->w_bufp->b_flag |= BFINVS;
    wp = wheadp;
    while (wp != NULL) {
        wp->w_flag |= WFMODE;
        wp = wp->w_wndp;
    }
    return TRUE;
}

int deskey(int f, int n)
{               /* describe the command for a certain key */
    int c;      /* key to describe */
    char *ptr;  /* string pointer to scan output strings */
    char outseq[NSTRING];   /* output buffer for command sequence */

    /* prompt the user to type us a key to describe */
    mlwrite(": describe-key ");

    /* get the command sequence to describe
       change it to something we can print as well */
    c = getckey( FALSE) ;
    mlwrite( ": describe-key 0x%x, ", c) ;
    cmdstr( c, &outseq[ 0]) ;

    /* and dump it out */
    ostring(outseq);
    ostring(" ");

    /* find the right ->function */
    if ((ptr = getfname(getbind(c))) == NULL)
        ptr = "Not Bound";

    /* output the command sequence */
    ostring(ptr);
    return TRUE;
}

/*
 * bindtokey:
 *  add a new key to the key binding table
 *
 * int f, n;        command arguments [IGNORED]
 */
int bindtokey(int f, int n)
{
    unsigned int c;      /* command key to bind */
    fn_t kfunc;      /* ptr to the requested function to bind to */
    struct key_tab *ktp; /* pointer into the command table */
    int found;       /* matched command flag */
    char outseq[80];     /* output buffer for keystroke sequence */

    /* prompt the user to type in a key to bind */
    mlwrite(": bind-to-key ");

    /* get the function name to bind it to */
    kfunc = getname();
    if (kfunc == NULL) {
        mlwrite("(No such function)");
        return FALSE;
    }
    ostring(" ");

    /* get the command sequence to bind */
    c = getckey((kfunc == metafn) || (kfunc == cex) ||
            (kfunc == unarg) || (kfunc == ctrlg));

    /* change it to something we can print as well */
    cmdstr(c, &outseq[0]);

    /* and dump it out */
    ostring(outseq);

    /* if the function is a prefix key */
    if (kfunc == metafn || kfunc == cex ||
        kfunc == unarg || kfunc == ctrlg) {

        /* search for an existing binding for the prefix key */
        ktp = &keytab[0];
        found = FALSE;
        while (ktp->k_fp != NULL) {
            if (ktp->k_fp == kfunc)
                unbindchar(ktp->k_code);
            ++ktp;
        }

        /* reset the appropriate global prefix variable */
        if (kfunc == metafn)
            metac = c;
        if (kfunc == cex)
            ctlxc = c;
        if (kfunc == unarg)
            reptc = c;
        if (kfunc == ctrlg)
            abortc = c;
    }

    /* search the table to see if it exists */
    ktp = &keytab[0];
    found = FALSE;
    while (ktp->k_fp != NULL) {
        if (ktp->k_code == c) {
            found = TRUE;
            break;
        }
        ++ktp;
    }

    if (found) {        /* it exists, just change it then */
        ktp->k_fp = kfunc;
    } else {        /* otherwise we need to add it to the end */
        /* if we run out of binding room, bitch */
        if (ktp >= &keytab[NBINDS]) {
            mlwrite("Binding table FULL!");
            return FALSE;
        }

        ktp->k_code = c;    /* add keycode */
        ktp->k_fp = kfunc;  /* and the function pointer */
        ++ktp;      /* and make sure the next is null */
        ktp->k_code = 0;
        ktp->k_fp = NULL;
    }
    return TRUE;
}

/*
 * unbindkey:
 *  delete a key from the key binding table
 *
 * int f, n;        command arguments [IGNORED]
 */
int unbindkey(int f, int n)
{
    int c;      /* command key to unbind */
    char outseq[80];    /* output buffer for keystroke sequence */

    /* prompt the user to type in a key to unbind */
    mlwrite(": unbind-key ");

    /* get the command sequence to unbind */
    c = getckey(FALSE); /* get a command sequence */

    /* change it to something we can print as well */
    cmdstr(c, &outseq[0]);

    /* and dump it out */
    ostring(outseq);

    /* if it isn't bound, bitch */
    if (unbindchar(c) == FALSE) {
        mlwrite("(Key not bound)");
        return FALSE;
    }
    return TRUE;
}


/*
 * unbindchar()
 *
 * int c;       command key to unbind
 */
static int unbindchar( unsigned c) {
    struct key_tab *ktp;   /* pointer into the command table */
    struct key_tab *sktp;  /* saved pointer into the command table */
    int found;             /* matched command flag */

    /* search the table to see if the key exists */
    ktp = &keytab[0];
    found = FALSE;
    while (ktp->k_fp != NULL) {
        if (ktp->k_code == c) {
            found = TRUE;
            break;
        }
        ++ktp;
    }

    /* if it isn't bound, bitch */
    if (!found)
        return FALSE;

    /* save the pointer and scan to the end of the table */
    sktp = ktp;
    while (ktp->k_fp != NULL)
        ++ktp;
    --ktp;          /* backup to the last legit entry */

    /* copy the last entry to the current one */
    sktp->k_code = ktp->k_code;
    sktp->k_fp = ktp->k_fp;

    /* null out the last one */
    ktp->k_code = 0;
    ktp->k_fp = NULL;
    return TRUE;
}

/* describe bindings
 * bring up a fake buffer and list the key bindings
 * into it with view mode
 */
int desbind(int f, int n)
#if APROP
{
    buildlist( "") ;
    return TRUE;
}

int apro(int f, int n)
{               /* Apropos (List functions that match a substring) */
    char mstring[NSTRING];  /* string to match cmd names to */
    int status;     /* status return */

    status = mlreply("Apropos string: ", mstring, NSTRING - 1);
    if (status == ABORT)
        return status;

    return buildlist( mstring) ;
}

/*
 * build a binding list (limited or full)
 *
 * char *mstring;   match string if a partial list, "" matches all
 */
static int buildlist( char *mstring)
#endif
{
    struct window *wp;         /* scanning pointer to windows */
    struct key_tab *ktp;  /* pointer into the command table */
    struct name_bind *nptr;          /* pointer into the name binding table */
    struct buffer *bp;    /* buffer to put binding list into */
    char outseq[80];      /* output buffer for keystroke sequence */

    /* split the current window to make room for the binding list */
    if (splitwind(FALSE, 1) == FALSE)
        return FALSE;

    /* and get a buffer for it */
    bp = bfind("*Binding list*", TRUE, 0);
    if (bp == NULL || bclear(bp) == FALSE) {
        mlwrite("Can not display binding list");
        return FALSE;
    }

    /* let us know this is in progress */
    mlwrite("(Building binding list)");

    /* disconect the current buffer */
    if (--curbp->b_nwnd == 0) { /* Last use.            */
        curbp->b_dotp = curwp->w_dotp;
        curbp->b_doto = curwp->w_doto;
        curbp->b_markp = curwp->w_markp;
        curbp->b_marko = curwp->w_marko;
    }

    /* connect the current window to this buffer */
    curbp = bp;     /* make this buffer current in current window */
    bp->b_mode = 0;     /* no modes active in binding list */
    bp->b_nwnd++;       /* mark us as more in use */
    wp = curwp;
    wp->w_bufp = bp;
    wp->w_linep = bp->b_linep;
    wp->w_flag = WFHARD | WFFORCE;
    wp->w_dotp = bp->b_dotp;
    wp->w_doto = bp->b_doto;
    wp->w_markp = NULL;
    wp->w_marko = 0;

    /* build the contents of this window, inserting it line by line */
    for( nptr = &names[ 0] ; nptr->n_func != NULL ; nptr++) {
	    int cpos ;	/* current position to use in outseq */

#if APROP
        /* if we are executing an apropos command..... */
            /* and current string doesn't include the search string */
        if( *mstring && strinc( nptr->n_name, mstring) == FALSE)
			continue ;
#endif
        /* add in the command name */
        strncpy( outseq, nptr->n_name, sizeof outseq - 1) ;
        outseq[ sizeof outseq - 1] = '\0' ;
        cpos = strlen(outseq);

        /* search down any keys bound to this */
        ktp = &keytab[0];
        while (ktp->k_fp != NULL) {
            if (ktp->k_fp == nptr->n_func) {
                /* padd out some spaces */
                while (cpos < 28)
                    outseq[cpos++] = ' ';

                /* add in the command sequence */
                cmdstr(ktp->k_code, &outseq[cpos]);
                strcat(outseq, "\n");

                /* and add it as a line into the buffer */
                if (linstr(outseq) != TRUE)
                    return FALSE;

                cpos = 0;   /* and clear the line */
            }
            ++ktp;
        }

        /* if no key was bound, we need to dump it anyway */
        if (cpos > 0) {
            outseq[cpos++] = '\n';
            outseq[cpos] = 0;
            if (linstr(outseq) != TRUE)
                return FALSE;
        }
    }

    curwp->w_bufp->b_mode |= MDVIEW;    /* put this buffer view mode */
    curbp->b_flag &= ~BFCHG;    /* don't flag this as a change */
    wp->w_dotp = lforw(bp->b_linep);    /* back to the beginning */
    wp->w_doto = 0;
    wp = wheadp;        /* and update ALL mode lines */
    while (wp != NULL) {
        wp->w_flag |= WFMODE;
        wp = wp->w_wndp;
    }
    mlwrite("");        /* clear the mode line */
    return TRUE;
}

#if APROP

/*
 * does source include sub?
 *
 * char *source;    string to search in
 * char *sub;       substring to look for
 */
static int strinc( char *source, char *sub) {
    /* for each character in the source string */
    for( ; *source ; source++) {
		char *nxtsp ;   /* next ptr into source */
		char *tp ;		/* ptr into substring */

        nxtsp = source;

        /* is the substring here? */
        for( tp = sub ; *tp ; tp++)
            if( *nxtsp++ != *tp)
                break ;

        /* yes, return a success */
        if( *tp == 0)
            return TRUE ;
    }

    return FALSE ;
}
#endif

/*
 * get a command key sequence from the keyboard
 *
 * int mflag;       going for a meta sequence?
 */
static unsigned int getckey( int mflag) {
    unsigned int c; /* character fetched */

    /* check to see if we are executing a command line */
    if (clexec) {
	    char tok[ NSTRING] ;  /* command incoming */

        macarg( tok, sizeof tok) ;    /* get the next token */
        return stock(tok);
    }

    /* or the normal way */
    if (mflag)
        c = get1key();
    else
        c = getcmd();
    return c;
}

/*
 * execute the startup file
 *
 * char *fname;    name of startup file (null if default)
 */
int startup( const char *fname) {
    if( !fname || *fname == 0)		/* use default if empty parameter */
    	fname = rcfname ;

	fname = flook( fname, TRUE) ;	/* look up the startup file */
    if( fname == NULL)    			/* if it isn't around, don't sweat it */
        return TRUE ;

    return dofile( fname) ;			/* otherwise, execute the sucker */
}

/*
 * change a key command to a string we can print out
 *
 * int c;       sequence to translate
 * char *seq;       destination string for sequence
 */
static void cmdstr( int c, char *seq) {
    char *ptr;      /* pointer into current position in sequence */

    ptr = seq;

    /* apply meta sequence if needed */
    if (c & META) {
        *ptr++ = 'M';
        *ptr++ = '-';
    }

    /* apply ^X sequence if needed */
    if (c & CTLX) {
        *ptr++ = '^';
        *ptr++ = 'X';
    }

    /* apply SPEC sequence if needed */
    if (c & SPEC) {
        *ptr++ = 'F';
        *ptr++ = 'N';
    }

    /* apply control sequence if needed */
    if (c & CONTROL) {
        *ptr++ = '^';
    }

    /* and output the final sequence */

    *ptr++ = c & 255;   /* strip the prefixes */

    *ptr = 0;       /* terminate the string */
}

/*
 * This function looks a key binding up in the binding table
 *
 * int c;       key to find what is bound to it
 */
fn_t getbind( unsigned c) {
    struct key_tab *ktp;

    ktp = &keytab[0];  /* Look in key table. */
    while (ktp->k_fp != NULL) {
        if (ktp->k_code == c)
            return ktp->k_fp;
        ++ktp;
    }

    /* no such binding */
    return NULL;
}

/*
 * getfname:
 *  This function takes a ptr to function and gets the name
 *  associated with it.
 */
static char *getfname(fn_t func)
{
    struct name_bind *nptr; /* pointer into the name binding table */

    /* skim through the table, looking for a match */
    nptr = &names[0];
    while (nptr->n_func != NULL) {
        if (nptr->n_func == func)
            return nptr->n_name;
        ++nptr;
    }
    return NULL;
}

/*
 * match fname to a function in the names table
 * and return any match or NULL if none
 *
 * char *fname;     name to attempt to match
 */
int (*fncmatch(char *fname)) (int, int)
{
    struct name_bind *ffp;  /* pointer to entry in name binding table */

    /* scan through the table, returning any match */
    ffp = &names[0];
    while (ffp->n_func != NULL) {
        if (strcmp(fname, ffp->n_name) == 0)
            return ffp->n_func;
        ++ffp;
    }
    return NULL;
}

/*
 * stock:
 *  String key name TO Command Key
 *
 * char *keyname;   name of key to translate to Command key form
 */
static unsigned int stock( char *keyname) {
    unsigned int c; /* key sequence to return */

    /* parse it up */
    c = 0;

    /* first, the META prefix */
    if (*keyname == 'M' && *(keyname + 1) == '-') {
        c = META;
        keyname += 2;
    }

    /* next the function prefix */
    if (*keyname == 'F' && *(keyname + 1) == 'N') {
        c |= SPEC;
        keyname += 2;
    }

    /* control-x as well... (but not with FN) */
    if (*keyname == '^' && *(keyname + 1) == 'X' && !(c & SPEC)) {
        c |= CTLX;
        keyname += 2;
    }

    /* a control char? */
    if (*keyname == '^' && *(keyname + 1) != 0) {
        c |= CONTROL;
        ++keyname;
    }
    if (*keyname < 32) {
        c |= CONTROL;
        *keyname += 'A';
    }


    /* make sure we are not lower case (not with function keys) */
    if (*keyname >= 'a' && *keyname <= 'z' && !(c & SPEC))
        *keyname -= 32;

    /* the final sequence... */
    c |= *keyname & 0xFFU ;
    return c;
}

/*
 * string key name to binding name....
 *
 * char *skey;      name of keey to get binding for
 */
char *transbind(char *skey)
{
    char *bindname;

    bindname = getfname(getbind(stock(skey)));
    if (bindname == NULL)
        bindname = "ERROR";

    return bindname;
}