Updated RELEASE_NOTES.

[mp-5.x.git] / mp_core.c

/*

    Minimum Profit - Programmer Text Editor

    Copyright (C) 1991-2009 Angel Ortega <angel@triptico.com>

    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License
    as published by the Free Software Foundation; either version 2
    of the License, or (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

    http://www.triptico.com

*/

#include "config.h"

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

#include "mpdm.h"
#include "mpsl.h"

#include "mp.h"

/** data **/

/* exit requested? */
int mp_exit_requested = 0;

/* main namespace */
mpdm_t mp = NULL;

/** private data for drawing syntax-highlighted text **/

struct drw_1_info {
        mpdm_t txt;             /* the document */
        mpdm_t syntax;          /* syntax highlight information */
        mpdm_t colors;          /* color definitions (for attributes) */
        mpdm_t word_color_func; /* word color function (just for detection) */
        mpdm_t last_search;     /* last search regex */
        int normal_attr;        /* normal attr */
        int cursor_attr;        /* cursor attr */
        int n_lines;            /* number of processed lines */
        int p_lines;            /* number of prereaded lines */
        int t_lines;            /* total lines in document */
        int vx;                 /* first visible column */
        int vy;                 /* first visible line */
        int tx;                 /* horizontal window size */
        int ty;                 /* vertical window size */
        int tab_size;           /* tabulator size */
        int mod;                /* modify count */
        int preread_lines;      /* lines to pre-read (for synhi blocks) */
        int mark_eol;           /* mark end of lines */
        int redraw;             /* redraw trigger */
};

struct drw_1_info drw_1;
struct drw_1_info drw_1_o;

static struct {
        int x;                  /* cursor x */
        int y;                  /* cursor y */
        int *offsets;           /* offsets of lines */
        char *attrs;            /* attributes */
        int visible;            /* offset to the first visible character */
        int cursor;             /* offset to cursor */
        wchar_t *ptr;           /* pointer to joined data */
        int size;               /* size of joined data */
        int matchparen_offset;  /* offset to matched paren */
        int matchparen_o_attr;  /* original attribute there */
        int cursor_o_attr;      /* original attribute under cursor */
        mpdm_t v;               /* the data */
        mpdm_t old;             /* the previously generated array */
        int mark_offset;        /* offset to the marked block */
        int mark_size;          /* size of mark_o_attr */
        char *mark_o_attr;      /* saved attributes for the mark */
} drw_2;

/** code **/

#define MP_REAL_TAB_SIZE(x) (drw_1.tab_size - ((x) % drw_1.tab_size))

static int drw_wcwidth(int x, wchar_t c)
/* returns the wcwidth of c, or the tab spaces for
   the x column if it's a tab */
{
        int r;

        switch (c) {
        case L'\n':
                r = 1;
                break;
        case L'\t':
                r = MP_REAL_TAB_SIZE(x);
                break;
        default:
                r = mpdm_wcwidth(c);
                break;
        }

        return r < 0 ? 1 : r;
}


int drw_vx2x(mpdm_t str, int vx)
/* returns the character in str that is on column vx */
{
        const wchar_t *ptr = str->data;
        int n, x;

        for (n = x = 0; n < vx && ptr[x] != L'\0'; x++)
                n += drw_wcwidth(n, ptr[x]);

        return x;
}


int drw_x2vx(mpdm_t str, int x)
/* returns the column where the character at offset x seems to be */
{
        const wchar_t *ptr = str->data;
        int n, vx;

        for (n = vx = 0; n < x && ptr[n] != L'\0'; n++)
                vx += drw_wcwidth(vx, ptr[n]);

        return vx;
}


static int drw_line_offset(int l)
/* returns the offset into v for line number l */
{
        return drw_2.offsets[l - drw_1.vy + drw_1.p_lines];
}


static int drw_adjust_y(int y, int *vy, int ty)
/* adjusts the visual y position */
{
        int t = *vy;

        /* is y above the first visible line? */
        if (y < *vy)
                *vy = y;

        /* is y below the last visible line? */
        if (y > *vy + (ty - 2))
                *vy = y - (ty - 2);

        return t != *vy;
}


static int drw_adjust_x(int x, int y, int *vx, int tx, wchar_t * ptr)
/* adjust the visual x position */
{
        int n, m;
        int t = *vx;

        /* calculate the column for the cursor position */
        for (n = m = 0; n < x; n++, ptr++)
                m += drw_wcwidth(m, *ptr);

        /* if new cursor column is nearer the leftmost column, set */
        if (m < *vx)
                *vx = m;

        /* if new cursor column is further the rightmost column, set */
        if (m > *vx + (tx - 1))
                *vx = m - (tx - 1);

        return t != *vx;
}


static int drw_get_attr(wchar_t * color_name)
/* returns the attribute number for a color */
{
        mpdm_t v;
        int attr = 0;

        if ((v = mpdm_hget_s(drw_1.colors, color_name)) != NULL)
                attr = mpdm_ival(mpdm_hget_s(v, L"attr"));

        return attr;
}


static int drw_prepare(mpdm_t doc)
/* prepares the document for screen drawing */
{
        mpdm_t window = mpdm_hget_s(mp, L"window");
        mpdm_t config = mpdm_hget_s(mp, L"config");
        mpdm_t txt = mpdm_hget_s(doc, L"txt");
        mpdm_t lines = mpdm_hget_s(txt, L"lines");
        int x = mpdm_ival(mpdm_hget_s(txt, L"x"));
        int y = mpdm_ival(mpdm_hget_s(txt, L"y"));
        int n;

        drw_1.vx = mpdm_ival(mpdm_hget_s(txt, L"vx"));
        drw_1.vy = mpdm_ival(mpdm_hget_s(txt, L"vy"));
        drw_1.tx = mpdm_ival(mpdm_hget_s(window, L"tx"));
        drw_1.ty = mpdm_ival(mpdm_hget_s(window, L"ty"));
        drw_1.tab_size = mpdm_ival(mpdm_hget_s(config, L"tab_size"));
        drw_1.mod = mpdm_ival(mpdm_hget_s(txt, L"mod"));
        drw_1.preread_lines = mpdm_ival(mpdm_hget_s(config, L"preread_lines"));
        drw_1.mark_eol = mpdm_ival(mpdm_hget_s(config, L"mark_eol"));
        drw_1.t_lines = mpdm_size(lines);

        /* adjust the visual y coordinate */
        if (drw_adjust_y(y, &drw_1.vy, drw_1.ty))
                mpdm_hset_s(txt, L"vy", MPDM_I(drw_1.vy));

        /* adjust the visual x coordinate */
        if (drw_adjust_x(x, y, &drw_1.vx, drw_1.tx, mpdm_string(mpdm_aget(lines, y))))
                mpdm_hset_s(txt, L"vx", MPDM_I(drw_1.vx));

        /* get the maximum prereadable lines */
        drw_1.p_lines = drw_1.vy > drw_1.preread_lines ? drw_1.preread_lines : drw_1.vy;

        /* maximum lines */
        drw_1.n_lines = drw_1.ty + drw_1.p_lines;

        /* get the mp.colors structure and the most used attributes */
        drw_1.colors = mpdm_hget_s(mp, L"colors");
        drw_1.normal_attr = drw_get_attr(L"normal");
        drw_1.cursor_attr = drw_get_attr(L"cursor");

        /* store the syntax highlight structure */
        drw_1.syntax = mpdm_hget_s(doc, L"syntax");

        drw_1.word_color_func = mpdm_hget_s(mp, L"word_color_func");

        mpdm_unref(drw_1.txt);
        drw_1.txt = mpdm_ref(txt);

        drw_2.x = x;
        drw_2.y = y;

        /* last search regex */
        drw_1.last_search = mpdm_hget_s(mp, L"last_search");

        /* redraw trigger */
        drw_1.redraw = mpdm_ival(mpdm_hget_s(mp, L"redraw_counter"));

        /* compare drw_1 with drw_1_o; if they are the same,
           no more expensive calculations on drw_2 are needed */
        if (memcmp(&drw_1, &drw_1_o, sizeof(drw_1)) == 0)
                return 0;

        /* different; store now */
        memcpy(&drw_1_o, &drw_1, sizeof(drw_1_o));

        /* alloc space for line offsets */
        drw_2.offsets = realloc(drw_2.offsets, drw_1.n_lines * sizeof(int));

        drw_2.ptr = NULL;
        drw_2.size = 0;

        /* add first line */
        drw_2.ptr = mpdm_pokev(drw_2.ptr, &drw_2.size,
                               mpdm_aget(lines, drw_1.vy - drw_1.p_lines));

        /* first line start at 0 */
        drw_2.offsets[0] = 0;

        /* add the following lines and store their offsets */
        for (n = 1; n < drw_1.n_lines; n++) {
                /* add the separator */
                drw_2.ptr = mpdm_poke(drw_2.ptr, &drw_2.size, L"\n", 1, sizeof(wchar_t));

                /* this line starts here */
                drw_2.offsets[n] = drw_2.size;

                /* now add it */
                drw_2.ptr = mpdm_pokev(drw_2.ptr, &drw_2.size,
                                       mpdm_aget(lines, n + drw_1.vy - drw_1.p_lines));
        }

        drw_2.ptr = mpdm_poke(drw_2.ptr, &drw_2.size, L"", 1, sizeof(wchar_t));
        drw_2.size--;

        /* now create a value */
        mpdm_unref(drw_2.v);
        drw_2.v = mpdm_ref(MPDM_ENS(drw_2.ptr, drw_2.size));

        /* alloc and init space for the attributes */
        drw_2.attrs = realloc(drw_2.attrs, drw_2.size + 1);
        memset(drw_2.attrs, drw_1.normal_attr, drw_2.size + 1);

        drw_2.visible = drw_line_offset(drw_1.vy);

        return 1;
}


static int drw_fill_attr(int attr, int offset, int size)
/* fill an attribute */
{
        if (attr != -1)
                memset(drw_2.attrs + offset, attr, size);

        return offset + size;
}


static int drw_fill_attr_regex(int attr)
/* fills with an attribute the last regex match */
{
        return drw_fill_attr(attr, mpdm_regex_offset, mpdm_regex_size);
}


static void drw_words(void)
/* fills the attributes for separate words */
{
        mpdm_t r, t;
        int o = drw_2.visible;
        mpdm_t word_color = NULL;
        mpdm_t word_color_func = NULL;

        /* take the hash of word colors, if any */
        if ((word_color = mpdm_hget_s(mp, L"word_color")) == NULL)
                return;

        /* get the regex for words */
        if ((r = mpdm_hget_s(mp, L"word_regex")) == NULL)
                return;

        /* get the word color function */
        word_color_func = mpdm_hget_s(mp, L"word_color_func");

        while ((t = mpdm_regex(r, drw_2.v, o)) != NULL) {
                int attr = -1;
                mpdm_t v;

                if ((v = mpdm_hget(word_color, t)) != NULL)
                        attr = mpdm_ival(v);
                else if (word_color_func != NULL)
                        attr = mpdm_ival(mpdm_exec_1(word_color_func, t));

                o = drw_fill_attr_regex(attr);
        }
}


static void drw_multiline_regex(mpdm_t a, int attr)
/* sets the attribute to all matching (possibly multiline) regexes */
{
        int n;

        for (n = 0; n < mpdm_size(a); n++) {
                mpdm_t r = mpdm_aget(a, n);
                int o = 0;

                /* if the regex is an array, it's a pair of
                   'match from this' / 'match until this' */
                if (r->flags & MPDM_MULTIPLE) {
                        mpdm_t rs = mpdm_aget(r, 0);
                        mpdm_t re = mpdm_aget(r, 1);

                        while (mpdm_regex(rs, drw_2.v, o)) {
                                int s;

                                /* fill the matched part */
                                o = drw_fill_attr_regex(attr);

                                /* try to match the end */
                                if (mpdm_regex(re, drw_2.v, o)) {
                                        /* found; fill the attribute
                                           to the end of the match */
                                        s = mpdm_regex_size + (mpdm_regex_offset - o);
                                }
                                else {
                                        /* not found; fill to the end
                                           of the document */
                                        s = drw_2.size - o;
                                }

                                /* fill to there */
                                o = drw_fill_attr(attr, o, s);
                        }
                }
                else {
                        /* it's a scalar: */
                        /* while the regex matches, fill attributes */
                        while (mpdm_regex(r, drw_2.v, o))
                                o = drw_fill_attr_regex(attr);
                }
        }
}


static void drw_blocks(void)
/* fill attributes for multiline blocks */
{
        mpdm_t defs;
        int n;

        /* no definitions? return */
        if (drw_1.syntax == NULL || (defs = mpdm_hget_s(drw_1.syntax, L"defs")) == NULL)
                return;

        for (n = 0; n < mpdm_size(defs); n += 2) {
                mpdm_t attr;
                mpdm_t list;

                /* get the attribute */
                attr = mpdm_aget(defs, n);
                attr = mpdm_hget(drw_1.colors, attr);
                attr = mpdm_hget_s(attr, L"attr");

                /* get the list for this word color */
                list = mpdm_aget(defs, n + 1);

                drw_multiline_regex(list, mpdm_ival(attr));
        }
}


static void drw_selection(void)
/* draws the selected block, if any */
{
        mpdm_t mark;
        int bx, by, ex, ey, vertical;
        int so, eo;
        int mby, mey;
        int line_offset, next_line_offset;
        int y;
        int len;
        int attr;

        /* no mark? return */
        if ((mark = mpdm_hget_s(drw_1.txt, L"mark")) == NULL)
                return;

        bx = mpdm_ival(mpdm_hget_s(mark, L"bx"));
        by = mpdm_ival(mpdm_hget_s(mark, L"by"));
        ex = mpdm_ival(mpdm_hget_s(mark, L"ex"));
        ey = mpdm_ival(mpdm_hget_s(mark, L"ey"));
        vertical  = mpdm_ival(mpdm_hget_s(mark, L"vertical"));

        /* if block is not visible, return */
        if (ey < drw_1.vy || by > drw_1.vy + drw_1.ty)
                return;

        so = by < drw_1.vy ? drw_2.visible : drw_line_offset(by) + bx;
        eo = ey >= drw_1.vy + drw_1.ty ? drw_2.size : drw_line_offset(ey) + ex;

        /* alloc space and save the attributes being destroyed */
        drw_2.mark_offset = so;
        drw_2.mark_size = eo - so + 1;
        drw_2.mark_o_attr = malloc(eo - so + 1);
        memcpy(drw_2.mark_o_attr, &drw_2.attrs[so], eo - so + 1);

        if (vertical == 0) {
                /* normal selection */
                drw_fill_attr(drw_get_attr(L"selection"), so, eo - so);
        }
        else {
                /* vertical selection */
                mby = by <  drw_1.vy ? drw_1.vy : by;
                mey = ey >= drw_1.vy + drw_1.ty ? drw_1.vy + drw_1.ty : ey;
                line_offset = drw_line_offset(mby);
                attr = drw_get_attr(L"selection");
                for (y = mby; y <= mey; y++) {
                        next_line_offset = drw_line_offset(y+1);
                        len = next_line_offset - line_offset - 1;
                        so = bx > len ? -1 : bx;
                        eo = ex > len ? len : ex;

                        if (so >= 0 && eo >= so)
                                drw_fill_attr(attr, line_offset+ so, eo - so + 1);

                        line_offset = next_line_offset;
                }
        }       
}


static void drw_search_hit(void)
/* colorize the search hit, if any */
{
        if (drw_1.last_search != NULL) {
                mpdm_t l = mpdm_ref(MPDM_A(0));

                mpdm_aset(l, drw_1.last_search, 0);
                drw_multiline_regex(l, drw_get_attr(L"search"));
                mpdm_unref(l);
        }
}


static void drw_cursor(void)
/* fill the attribute for the cursor */
{
        /* calculate the cursor offset */
        drw_2.cursor = drw_line_offset(drw_2.y) + drw_2.x;

        drw_2.cursor_o_attr = drw_2.attrs[drw_2.cursor];
        drw_fill_attr(drw_1.cursor_attr, drw_2.cursor, 1);
}


static void drw_matching_paren(void)
/* highlights the matching paren */
{
        int o = drw_2.cursor;
        int i = 0;
        wchar_t c;

        /* by default, no offset has been found */
        drw_2.matchparen_offset = -1;

        /* find the opposite and the increment (direction) */
        switch (drw_2.ptr[o]) {
        case L'(':
                c = L')';
                i = 1;
                break;
        case L'{':
                c = L'}';
                i = 1;
                break;
        case L'[':
                c = L']';
                i = 1;
                break;
        case L')':
                c = L'(';
                i = -1;
                break;
        case L'}':
                c = L'{';
                i = -1;
                break;
        case L']':
                c = L'[';
                i = -1;
                break;
        }

        /* if a direction is set, do the searching */
        if (i) {
                wchar_t s = drw_2.ptr[o];
                int m = 0;
                int l = i == -1 ? drw_2.visible - 1 : drw_2.size;

                while (o != l) {
                        if (drw_2.ptr[o] == s) {
                                /* found the same */
                                m++;
                        }
                        else if (drw_2.ptr[o] == c) {
                                /* found the opposite */
                                if (--m == 0) {
                                        /* found! fill and exit */
                                        drw_2.matchparen_offset = o;
                                        drw_2.matchparen_o_attr = drw_2.attrs[o];
                                        drw_fill_attr(drw_get_attr(L"matching"), o, 1);
                                        break;
                                }
                        }

                        o += i;
                }
        }
}


static mpdm_t drw_push_pair(mpdm_t l, int i, int a, wchar_t * tmp)
/* pushes a pair of attribute / string into l */
{
        /* create the array, if doesn't exist yet */
        if (l == NULL)
                l = MPDM_A(0);

        /* finish the string */
        tmp[i] = L'\0';

        /* special magic: if the attribute is the
           one of the cursor and the string is more than
           one character, create two strings; the
           cursor is over a tab */
        if (a == drw_1.cursor_attr && i > 1) {
                mpdm_push(l, MPDM_I(a));
                mpdm_push(l, MPDM_NS(tmp, 1));

                /* the rest of the string has the original attr */
                a = drw_2.cursor_o_attr;

                /* one char less */
                tmp[i - 1] = L'\0';
        }

        /* store the attribute and the string */
        mpdm_push(l, MPDM_I(a));
        mpdm_push(l, MPDM_S(tmp));

        return l;
}


#define BUF_LINE 128

static mpdm_t drw_line(int line)
/* creates a list of attribute / string pairs for the current line */
{
        mpdm_t l = NULL;
        int m, i, t, n;
        int o = drw_2.offsets[line + drw_1.p_lines];
        int a = drw_2.attrs[o];
        wchar_t tmp[BUF_LINE];
        wchar_t c;

        /* loop while not beyond the right margin */
        for (m = i = 0; m < drw_1.vx + drw_1.tx; m += t, o++) {
                /* take char and size */
                c = drw_2.ptr[o];
                t = drw_wcwidth(m, c);

                /* further the left margin? */
                if (m >= drw_1.vx) {
                        /* if the attribute is different or we're out of
                           temporary space, push and go on */
                        if (drw_2.attrs[o] != a || i >= BUF_LINE - t - 1) {
                                l = drw_push_pair(l, i, a, tmp);
                                i = 0;
                        }

                        /* size is 1, unless it's a tab */
                        n = c == L'\t' ? t : 1;

                        /* fill tabs with spaces */
                        if (c == L'\0' || c == L'\t')
                                c = L' ';

                        /* fill EOLs with special marks or spaces */
                        if (c == L'\n')
                                c = drw_1.mark_eol ? L'\xb6' : L' ';

                        /* if next char will not fit, use a space */
                        if (m + t > drw_1.vx + drw_1.tx)
                                c = L' ';
                }
                else {
                        /* left filler */
                        n = m + t - drw_1.vx;
                        c = L' ';
                }

                /* fill the string */
                for (; n > 0; n--)
                        tmp[i++] = c;

                a = drw_2.attrs[o];

                /* end of line? */
                if (drw_2.ptr[o] == L'\0' || drw_2.ptr[o] == L'\n')
                        break;
        }

        return drw_push_pair(l, i, a, tmp);
}


static mpdm_t drw_as_array(void)
/* returns an mpdm array of ty elements, which are also arrays of
   attribute - string pairs */
{
        mpdm_t a;
        int n;

        /* the array of lines */
        a = MPDM_A(drw_1.ty);

        /* push each line */
        for (n = 0; n < drw_1.ty; n++)
                mpdm_aset(a, drw_line(n), n);

        return a;
}


static mpdm_t drw_optimize_array(mpdm_t a, int optimize)
/* optimizes the array, NULLifying all lines that are the same as the last time */
{
        mpdm_t o = drw_2.old;
        mpdm_t r = a;

        if (optimize && o != NULL) {
                int n = 0;

                /* creates a copy */
                r = mpdm_clone(a);

                /* compare each array */
                while (n < mpdm_size(o) && n < mpdm_size(r)) {
                        /* if both lines are equal, optimize out */
                        if (mpdm_cmp(mpdm_aget(o, n), mpdm_aget(r, n)) == 0)
                                mpdm_aset(r, NULL, n);

                        n++;
                }
        }

        mpdm_unref(drw_2.old);
        drw_2.old = mpdm_ref(a);

        return r;
}


static void drw_restore_attrs(void)
/* restored the patched attrs */
{
        /* matching paren, if any */
        if (drw_2.matchparen_offset != -1)
                drw_fill_attr(drw_2.matchparen_o_attr, drw_2.matchparen_offset, 1);

        /* cursor */
        drw_fill_attr(drw_2.cursor_o_attr, drw_2.cursor, 1);

        /* marked block, if any */
        if (drw_2.mark_o_attr != NULL) {
                memcpy(&drw_2.attrs[drw_2.mark_offset], drw_2.mark_o_attr, drw_2.mark_size);

                free(drw_2.mark_o_attr);
                drw_2.mark_o_attr = NULL;
        }
}


static mpdm_t drw_draw(mpdm_t doc, int optimize)
/* main document drawing function: takes a document and returns an array of
   arrays of attribute / string pairs */
{
        mpdm_t r = NULL;

        if (drw_prepare(doc)) {
                /* colorize separate words */
                drw_words();

                /* colorize multiline blocks */
                drw_blocks();
        }

        /* now set the marked block (if any) */
        drw_selection();

        /* colorize the search hit */
        drw_search_hit();

        /* the cursor */
        drw_cursor();

        /* highlight the matching paren */
        drw_matching_paren();

        /* convert to an array of string / atribute pairs */
        r = drw_as_array();

        /* optimize */
        r = drw_optimize_array(r, optimize);

        /* restore the patched attrs */
        drw_restore_attrs();

        return r;
}


/** interface **/

mpdm_t mp_draw(mpdm_t doc, int optimize)
/* main generic drawing function: if the document has a 'paint' code,
   calls it; otherwise, call drw_draw() */
{
        mpdm_t r = NULL;
        static int ppp = 0;     /* previous private paint */
        mpdm_t f;

        /* if previous paint was private, disable optimizations */
        if (ppp)
                optimize = ppp = 0;

        if (doc != NULL) {
                if ((f = mpdm_hget_s(doc, L"paint")) != NULL) {
                        ppp = 1;
                        r = mpdm_exec_2(f, doc, MPDM_I(optimize));
                }
                else
                        r = drw_draw(doc, optimize);
        }

        /* if there is a global post_paint function, execute it */
        if ((f = mpdm_hget_s(mp, L"post_paint")) != NULL)
                r = mpdm_exec_1(f, r);

        /* if doc has a post_paint function, execute it */
        if ((f = mpdm_hget_s(doc, L"post_paint")) != NULL)
                r = mpdm_exec_1(f, r);

        return r;
}


#define THR_SPEED_STEP  10
#define THR_MAX_SPEED   7

int mp_keypress_throttle(int keydown)
/* processes key acceleration and throttle */
{
        static int keydowns = 0;
        static int seq = 0;
        int redraw = 0;

        if (keydown) {
                int speed;

                /* as keydowns accumulate, speed increases, which is the number
                   of cycles the redraw will be skipped (up to a maximum) */
                if ((speed = 1 + (++keydowns / THR_SPEED_STEP)) > THR_MAX_SPEED)
                        speed = THR_MAX_SPEED;

                if (++seq % speed == 0)
                        redraw = 1;
        }
        else {
                if (keydowns > 1)
                        redraw = 1;

                keydowns = 0;
        }

        return redraw;
}


mpdm_t mp_active(void)
/* interface to mp.active() */
{
        return mpdm_exec(mpdm_hget_s(mp, L"active"), NULL);
}


mpdm_t mp_process_action(mpdm_t action)
/* interface to mp.process_action() */
{
        return mpdm_exec_1(mpdm_hget_s(mp, L"process_action"), action);
}


mpdm_t mp_process_event(mpdm_t keycode)
/* interface to mp.process_event() */
{
        return mpdm_exec_1(mpdm_hget_s(mp, L"process_event"), keycode);
}


mpdm_t mp_set_y(mpdm_t doc, int y)
/* interface to mp.set_y() */
{
        return mpdm_exec_2(mpdm_hget_s(mp, L"set_y"), doc, MPDM_I(y));
}


mpdm_t mp_build_status_line(void)
/* interface to mp.build_status_line() */
{
        return mpdm_exec(mpdm_hget_s(mp, L"build_status_line"), NULL);
}


mpdm_t mp_get_history(mpdm_t key)
/* interface to mp.get_history() */
{
        return mpdm_exec_1(mpdm_hget_s(mp, L"get_history"), key);
}


mpdm_t mp_get_doc_names(void)
/* interface to mp.get_doc_names() */
{
        return mpdm_exec(mpdm_hget_s(mp, L"get_doc_names"), NULL);
}


mpdm_t mp_menu_label(mpdm_t action)
/* interface to mp.menu_label() */
{
        return mpdm_exec_1(mpdm_hget_s(mp, L"menu_label"), action);
}


mpdm_t mp_pending_key(void)
/* interface to mp.pending_key() */
{
        return mpdm_exec_1(mpdm_hget_s(mp, L"pending_key"), NULL);
}


mpdm_t mp_process_keyseq(mpdm_t key)
/* interface to mp.process_keyseq() */
{
        return mpdm_exec_1(mpdm_hget_s(mp, L"process_keyseq"), key);
}


mpdm_t mp_exit(mpdm_t args)
/* exit the editor (set mp_exit_requested) */
{
        mp_exit_requested = 1;

        return NULL;
}


mpdm_t mp_vx2x(mpdm_t args)
/* interface to drw_vx2x() */
{
        return MPDM_I(drw_vx2x(mpdm_aget(args, 0), mpdm_ival(mpdm_aget(args, 1))));
}


mpdm_t mp_x2vx(mpdm_t args)
/* interface to drw_x2vx() */
{
        return MPDM_I(drw_x2vx(mpdm_aget(args, 0), mpdm_ival(mpdm_aget(args, 1))));
}

mpdm_t mp_plain_load(mpdm_t args)
/* loads a plain file into an array (highly optimized one) */
{
        mpdm_t f = mpdm_aget(args, 0);
        mpdm_t a = MPDM_A(0);
        mpdm_t v;
        int chomped = 1;

        while ((v = mpdm_read(f)) != NULL) {
                const wchar_t *ptr = v->data;
                int size = v->size;

                /* chomp */
                if (size && ptr[size - 1] == L'\n') {
                        if (--size && ptr[size - 1] == L'\r')
                                --size;
                }
                else
                        chomped = 0;

                mpdm_push(a, MPDM_NS(ptr, size));
                mpdm_destroy(v);
        }

        /* if last line was chomped, add a last, empty one */
        if (chomped)
                mpdm_push(a, MPDM_LS(L""));

        return a;
}


void mp_startup(int argc, char *argv[])
{
        mpdm_t INC;

        mpsl_startup();

        /* reset the structures */
        memset(&drw_1, '\0', sizeof(drw_1));
        memset(&drw_1_o, '\0', sizeof(drw_1_o));

        /* create main namespace */
        mp = MPDM_H(0);
        mpdm_hset_s(mpdm_root(), L"mp", mp);

        /* basic functions and data */
        mpdm_hset_s(mp, L"x2vx", MPDM_X(mp_x2vx));
        mpdm_hset_s(mp, L"vx2x", MPDM_X(mp_vx2x));
        mpdm_hset_s(mp, L"exit", MPDM_X(mp_exit));
        mpdm_hset_s(mp, L"plain_load", MPDM_X(mp_plain_load));
        mpdm_hset_s(mp, L"window", MPDM_H(0));
        mpdm_hset_s(mp, L"drv", MPDM_H(0));

        /* version */
        mpdm_hset_s(mp, L"VERSION", MPDM_S(L"" VERSION));

        /* creates the INC (executable path) array */
        INC = MPDM_A(0);

        /* add installed library path */
        mpdm_push(INC, mpdm_strcat(mpdm_hget_s(mpdm_root(), L"APPDIR"),
                                   MPDM_MBS(CONFOPT_APPNAME))
            );

        /* set INC */
        mpdm_hset_s(mpdm_root(), L"INC", INC);

        if (!TRY_DRIVERS()) {
                printf("No usable driver found; exiting.\n");
                exit(1);
        }

        mpsl_argv(argc, argv);
}


void mp_mpsl(void)
{
        mpdm_t e;

        mpsl_eval(MPDM_LS(L"load('mp_core.mpsl');"), NULL);

        if ((e = mpdm_hget_s(mpdm_root(), L"ERROR")) != NULL) {
                mpdm_write_wcs(stdout, mpdm_string(e));
                printf("\n");
        }
}


void mp_shutdown(void)
{
        mpsl_shutdown();
}


int main(int argc, char *argv[])
{
        mp_startup(argc, argv);

        mp_mpsl();

        mp_shutdown();

        return 0;
}