fltk/src/Fl_Input_.cxx

//
// "$Id$"
//
// Common input widget routines for the Fast Light Tool Kit (FLTK).
//
// Copyright 1998-2009 by Bill Spitzak and others.
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Library General Public
// License as published by the Free Software Foundation; either
// version 2 of the License, or (at your option) any later version.
//
// This library 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
// Library General Public License for more details.
//
// You should have received a copy of the GNU Library General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
// USA.
//
// Please report all bugs and problems on the following page:
//
//     http://www.fltk.org/str.php
//

/** FIXME DOX: APIs not found
 fn int Fl_Input_::wordboundary(int i) const
  Returns true if position i is at the start or end of a word.

 fn int Fl_Input_::lineboundary(int i) const
  Returns true if position i is at the start or end of a line.

*/
// This is the base class for Fl_Input.  You can use it directly
// if you are one of those people who like to define their own
// set of editing keys.  It may also be useful for adding scrollbars
// to the input field.

#include <FL/Fl.H>
#include <FL/Fl_Input_.H>
#include <FL/Fl_Window.H>
#include <FL/fl_draw.H>
#include <FL/fl_ask.H>
#include <math.h>
#include <FL/fl_utf8.h>
#include "flstring.h"
#include <stdlib.h>
#include <ctype.h>

#define MAXBUF 1024

extern void fl_draw(const char*, int, float, float);

////////////////////////////////////////////////////////////////

// Copy string p..e to the buffer, replacing characters with ^X and \nnn
// as necessary.  Truncate if necessary so the resulting string and
// null terminator fits in a buffer of size n.  Return new end pointer.
const char* Fl_Input_::expand(const char* p, char* buf) const {
  char* o = buf;
  char* e = buf+(MAXBUF-4);
  const char* lastspace = p;
  char* lastspace_out = o;
  int width_to_lastspace = 0;
  int word_count = 0;
  int word_wrap;
//  const char *pe = p + strlen(p);

  if (input_type()==FL_SECRET_INPUT) {
    while (o<e && p < value_+size_) {
      if (fl_utf8len((char)p[0]) >= 1) *o++ = '*';
      p++;
    }

  } else while (o<e) {
    if (wrap() && (p >= value_+size_ || isspace(*p & 255))) {
      word_wrap = w() - Fl::box_dw(box()) - 2;
      width_to_lastspace += (int)fl_width(lastspace_out, o-lastspace_out);
      if (p > lastspace+1) {
	if (word_count && width_to_lastspace > word_wrap) {
	  p = lastspace; o = lastspace_out; break;
	}
	word_count++;
      }
      lastspace = p;
      lastspace_out = o;
    }

    if (p >= value_+size_) break;
    int c = *p++ & 255;
    if (c < ' ' || c == 127) {
      if (c=='\n' && input_type()==FL_MULTILINE_INPUT) {p--; break;}
      if (c == '\t' && input_type()==FL_MULTILINE_INPUT) {
        for (c = fl_utf_nb_char((uchar*)buf, o-buf)%8; c<8 && o<e; c++) {
          *o++ = ' ';
        }
      } else {
	*o++ = '^';
	*o++ = c ^ 0x40;
      }
    } else {
      *o++ = c;
    }
  }
  *o = 0;
  return p;
}

// After filling in such a buffer, find the width to e
double Fl_Input_::expandpos(
  const char* p,	// real string
  const char* e,	// pointer into real string
  const char* buf,	// conversion of real string by expand()
  int* returnn		// return offset into buf here
) const {
  int n = 0;
  int chr = 0;
  if (input_type()==FL_SECRET_INPUT) {
    while (p<e) {
      if (fl_utf8len((char)p[0]) >= 1) n++;
      p++;
    }
  } else while (p<e) {
    int c = *p & 255;
    if (c < ' ' || c == 127) {
      if (c == '\t' && input_type()==FL_MULTILINE_INPUT) {
         n += 8-(chr%8);
         chr += 8-(chr%8);
      } else n += 2;
    } else {
      n++;
    }
    chr += fl_utf8len((char)p[0]) >= 1;
    p++;
  }
  if (returnn) *returnn = n;
  return fl_width(buf, n);
}

////////////////////////////////////////////////////////////////

// minimal update:
// Characters from mu_p to end of widget are redrawn.
// If erase_cursor_only, small part at mu_p is redrawn.
// Right now minimal update just keeps unchanged characters from
// being erased, so they don't blink.

void Fl_Input_::minimal_update(int p) {
  if (damage() & FL_DAMAGE_ALL) return; // don't waste time if it won't be done
  if (damage() & FL_DAMAGE_EXPOSE) {
    if (p < mu_p) mu_p = p;
  } else {
    mu_p = p;
  }

  damage(FL_DAMAGE_EXPOSE);
  erase_cursor_only = 0;
}

void Fl_Input_::minimal_update(int p, int q) {
  if (q < p) p = q;
  minimal_update(p);
}

////////////////////////////////////////////////////////////////

static double up_down_pos;
static int was_up_down;

void Fl_Input_::setfont() const {
 fl_font(textfont(), textsize());
}

/**
  Draw the text in the passed bounding box.  If damage()
  & FL_DAMAGE_ALL is true, this assumes the area has
  already been erased to color(). Otherwise it does
  minimal update and erases the area itself.
*/
void Fl_Input_::drawtext(int X, int Y, int W, int H) {
  int do_mu = !(damage()&FL_DAMAGE_ALL);

  if (Fl::focus()!=this && !size()) {
    if (do_mu) { // we have to erase it if cursor was there
      draw_box(box(), X-Fl::box_dx(box()), Y-Fl::box_dy(box()),
               W+Fl::box_dw(box()), H+Fl::box_dh(box()), color());
    }
    return;
  }

  int selstart, selend;
  if (Fl::focus()!=this && /*Fl::selection_owner()!=this &&*/ Fl::pushed()!=this)
    selstart = selend = 0;
  else if (position() <= mark()) {
    selstart = position(); selend = mark();
  } else {
    selend = position(); selstart = mark();
  }

  setfont();
  const char *p, *e;
  char buf[MAXBUF];

  // count how many lines and put the last one into the buffer:
  // And figure out where the cursor is:
  int height = fl_height();
  int lines;
  int curx, cury;
  for (p=value(), curx=cury=lines=0; ;) {
    e = expand(p, buf);
    if (position() >= p-value() && position() <= e-value()) {
      curx = int(expandpos(p, value()+position(), buf, 0)+.5);
      if (Fl::focus()==this && !was_up_down) up_down_pos = curx;
      cury = lines*height;
      int newscroll = xscroll_;
      if (curx > newscroll+W-20) {
	// figure out scrolling so there is space after the cursor:
	newscroll = curx+20-W;
	// figure out the furthest left we ever want to scroll:
	int ex = int(expandpos(p, e, buf, 0))+2-W;
	// use minimum of both amounts:
	if (ex < newscroll) newscroll = ex;
      } else if (curx < newscroll+20) {
	newscroll = curx-20;
      }
      if (newscroll < 0) newscroll = 0;
      if (newscroll != xscroll_) {
	xscroll_ = newscroll;
	mu_p = 0; erase_cursor_only = 0;
      }
    }
    lines++;
    if (e >= value_+size_) break;
    p = e+1;
  }

  // adjust the scrolling:
  if (input_type()==FL_MULTILINE_INPUT) {
    int newy = yscroll_;
    if (cury < newy) newy = cury;
    if (cury > newy+H-height) newy = cury-H+height;
    if (newy < -1) newy = -1;
    if (newy != yscroll_) {yscroll_ = newy; mu_p = 0; erase_cursor_only = 0;}
  } else {
    yscroll_ = -(H-height)/2;
  }

  fl_push_clip(X, Y, W, H);
  Fl_Color tc = active_r() ? textcolor() : fl_inactive(textcolor());

  p = value();
  // visit each line and draw it:
  int desc = height-fl_descent();
  float xpos = (float)(X - xscroll_ + 1);
  int ypos = -yscroll_;
  for (; ypos < H;) {

    // re-expand line unless it is the last one calculated above:
    if (lines>1) e = expand(p, buf);

    if (ypos <= -height) goto CONTINUE; // clipped off top

    if (do_mu) {	// for minimal update:
      const char* pp = value()+mu_p; // pointer to where minimal update starts
      if (e < pp) goto CONTINUE2; // this line is before the changes
      if (readonly()) erase_cursor_only = 0; // this isn't the most efficient way
      if (erase_cursor_only && p > pp) goto CONTINUE2; // this line is after
      // calculate area to erase:
      float r = (float)(X+W);
      float xx;
      if (p >= pp) {
	xx = (float)X;
	if (erase_cursor_only) r = xpos+2;
	else if (readonly()) xx -= 3;
      } else {
	xx = xpos + (float)expandpos(p, pp, buf, 0);
	if (erase_cursor_only) r = xx+2;
	else if (readonly()) xx -= 3;
      }
      // clip to and erase it:
      fl_push_clip((int)xx-1-height/8, Y+ypos, (int)(r-xx+2+height/4), height);
      draw_box(box(), X-Fl::box_dx(box()), Y-Fl::box_dy(box()),
               W+Fl::box_dw(box()), H+Fl::box_dh(box()), color());
      // it now draws entire line over it
      // this should not draw letters to left of erased area, but
      // that is nyi.
    }

    // Draw selection area if required:
    if (selstart < selend && selstart <= e-value() && selend > p-value()) {
      const char* pp = value()+selstart;
      float x1 = xpos;
      int offset1 = 0;
      if (pp > p) {
	fl_color(tc);
	x1 += (float)expandpos(p, pp, buf, &offset1);
	fl_draw(buf, offset1, xpos, (float)(Y+ypos+desc));
      }
      pp = value()+selend;
      float x2 = (float)(X+W);
      int offset2;
      if (pp <= e) x2 = xpos + (float)expandpos(p, pp, buf, &offset2);
      else offset2 = strlen(buf);
      fl_color(selection_color());
      fl_rectf((int)(x1+0.5), Y+ypos, (int)(x2-x1+0.5), height);
      fl_color(fl_contrast(textcolor(), selection_color()));
      fl_draw(buf+offset1, offset2-offset1, x1, (float)(Y+ypos+desc));
      if (pp < e) {
	fl_color(tc);
	fl_draw(buf+offset2, strlen(buf+offset2), x2, (float)(Y+ypos+desc));
      }
    } else {
      // draw unselected text
      fl_color(tc);
      fl_draw(buf, strlen(buf), xpos, (float)(Y+ypos+desc));
    }

    if (do_mu) fl_pop_clip();

  CONTINUE2:
    // draw the cursor:
    if (Fl::focus() == this && selstart == selend &&
	position() >= p-value() && position() <= e-value()) {
      fl_color(cursor_color());
      if (readonly()) {
        fl_line((int)(xpos+curx-2.5f), Y+ypos+height-1,
	        (int)(xpos+curx+0.5f), Y+ypos+height-4,
	        (int)(xpos+curx+3.5f), Y+ypos+height-1);
      } else {
        fl_rectf((int)(xpos+curx+0.5), Y+ypos, 2, height);
      }
    }

  CONTINUE:
    ypos += height;
    if (e >= value_+size_) break;
    if (*e == '\n' || *e == ' ') e++;
    p = e;
  }

  // for minimal update, erase all lines below last one if necessary:
  if (input_type()==FL_MULTILINE_INPUT && do_mu && ypos<H
      && (!erase_cursor_only || p <= value()+mu_p)) {
    if (ypos < 0) ypos = 0;
    fl_push_clip(X, Y+ypos, W, H-ypos);
    draw_box(box(), X-Fl::box_dx(box()), Y-Fl::box_dy(box()),
             W+Fl::box_dw(box()), H+Fl::box_dh(box()), color());
    fl_pop_clip();
  }

  fl_pop_clip();
  if (Fl::focus() == this) {
       fl_set_spot(textfont(), textsize(),
               (int)xpos+curx, Y+ypos-fl_descent(), W, H, window());
  }
}

static int isword(char c) {
  return (c&128 || isalnum(c) || strchr("#%&-/@\\_~", c));
}

int Fl_Input_::word_end(int i) const {
  if (input_type() == FL_SECRET_INPUT) return size();
  //while (i < size() && !isword(index(i))) i++;
  while (i < size() && !isword(index(i))) i++;
  while (i < size() && isword(index(i))) i++;
  return i;
}

int Fl_Input_::word_start(int i) const {
  if (input_type() == FL_SECRET_INPUT) return 0;
//   if (i >= size() || !isword(index(i)))
//     while (i > 0 && !isword(index(i-1))) i--;
  while (i > 0 && !isword(index(i-1))) i--;
  while (i > 0 && isword(index(i-1))) i--;
  return i;
}

int Fl_Input_::line_end(int i) const {
  if (input_type() != FL_MULTILINE_INPUT) return size();

  if (wrap()) {
    // go to the start of the paragraph:
    int j = i;
    while (j > 0 && index(j-1) != '\n') j--;
    // now measure lines until we get past i, end of that line is real eol:
    setfont();
    for (const char* p=value()+j; ;) {
      char buf[MAXBUF];
      p = expand(p, buf);
      if (p-value() >= i) return p-value();
      p++;
    }
  } else {
    while (i < size() && index(i) != '\n') i++;
    return i;
  }
}

int Fl_Input_::line_start(int i) const {
  if (input_type() != FL_MULTILINE_INPUT) return 0;
  int j = i;
  while (j > 0 && index(j-1) != '\n') j--;
  if (wrap()) {
    // now measure lines until we get past i, start of that line is real eol:
    setfont();
    for (const char* p=value()+j; ;) {
      char buf[MAXBUF];
      const char* e = expand(p, buf);
      if (e-value() >= i) return p-value();
      p = e+1;
    }
  } else return j;
}

void Fl_Input_::handle_mouse(int X, int Y, int /*W*/, int /*H*/, int drag) {
  was_up_down = 0;
  if (!size()) return;
  setfont();

  const char *p, *e;
  char buf[MAXBUF];

  int theline = (input_type()==FL_MULTILINE_INPUT) ?
    (Fl::event_y()-Y+yscroll_)/fl_height() : 0;

  int newpos = 0;
  for (p=value();; ) {
    e = expand(p, buf);
    theline--; if (theline < 0) break;
    if (e >= value_+size_) break;
    p = e+1;
  }
  const char *l, *r, *t; double f0 = Fl::event_x()-X+xscroll_;
  for (l = p, r = e; l<r; ) {
    double f;
    int cw = fl_utf8len((char)l[0]);
    if (cw < 1) cw = 1;
    t = l+cw;
    f = X-xscroll_+expandpos(p, t, buf, 0);
    if (f <= Fl::event_x()) {l = t; f0 = Fl::event_x()-f;}
    else r = t-cw;
  }
  if (l < e) { // see if closer to character on right:
    double f1;
    int cw = fl_utf8len((char)l[0]);
    if (cw > 0) {
      f1 = X-xscroll_+expandpos(p, l + cw, buf, 0) - Fl::event_x();
      if (f1 < f0) l = l+cw;
    }
  }
  newpos = l-value();

  int newmark = drag ? mark() : newpos;
  if (Fl::event_clicks()) {
    if (newpos >= newmark) {
      if (newpos == newmark) {
	if (newpos < size()) newpos++;
	else newmark--;
      }
      if (Fl::event_clicks() > 1) {
	newpos = line_end(newpos);
	newmark = line_start(newmark);
      } else {
	newpos = word_end(newpos);
	newmark = word_start(newmark);
      }
    } else {
      if (Fl::event_clicks() > 1) {
	newpos = line_start(newpos);
	newmark = line_end(newmark);
      } else {
	newpos = word_start(newpos);
	newmark = word_end(newmark);
      }
    }
    // if the multiple click does not increase the selection, revert
    // to single-click behavior:
    if (!drag && (mark() > position() ?
                  (newmark >= position() && newpos <= mark()) :
                  (newmark >= mark() && newpos <= position()))) {
      Fl::event_clicks(0);
      newmark = newpos = l-value();
    }
  }
  position(newpos, newmark);
}

/**  See int Fl_Input_::position() const */
int Fl_Input_::position(int p, int m) {
  int is_same = 0;
  was_up_down = 0;
  if (p<0) p = 0;
  if (p>size()) p = size();
  if (m<0) m = 0;
  if (m>size()) m = size();
  if (p == m) is_same = 1;

  while (p < position_ && p > 0 && (size() - p) > 0 &&
       (fl_utf8len((char)(value() + p)[0]) < 1)) { p--; }
  int ul = fl_utf8len((char)(value() + p)[0]);
  while (p < size() && p > position_ && ul < 0) {
       p++;
       ul = fl_utf8len((char)(value() + p)[0]);
  }

  while (m < mark_ && m > 0 && (size() - m) > 0 &&
       (fl_utf8len((char)(value() + m)[0]) < 1)) { m--; }
  ul = fl_utf8len((char)(value() + m)[0]);
  while (m < size() && m > mark_ && ul < 0) {
       m++;
       ul = fl_utf8len((char)(value() + m)[0]);
  }
  if (is_same) m = p;
  if (p == position_ && m == mark_) return 0;


  //if (Fl::selection_owner() == this) Fl::selection_owner(0);
  if (p != m) {
    if (p != position_) minimal_update(position_, p);
    if (m != mark_) minimal_update(mark_, m);
  } else {
    // new position is a cursor
    if (position_ == mark_) {
      // old position was just a cursor
      if (Fl::focus() == this && !(damage()&FL_DAMAGE_EXPOSE)) {
	minimal_update(position_); erase_cursor_only = 1;
      }
    } else { // old position was a selection
      minimal_update(position_, mark_);
    }
  }
  position_ = p;
  mark_ = m;
  return 1;
}

/**
  Do the correct thing for arrow keys. Sets the position (and
  mark if <I>keepmark</I> is zero) to somewhere in the same line
  as <I>i</I>, such that pressing the arrows repeatedly will cause
  the point to move up and down.
*/
int Fl_Input_::up_down_position(int i, int keepmark) {
  // unlike before, i must be at the start of the line already!

  setfont();
  char buf[MAXBUF];
  const char* p = value()+i;
  const char* e = expand(p, buf);
  const char *l, *r, *t;
  for (l = p, r = e; l<r; ) {
    t = l+(r-l+1)/2;
    int f = (int)expandpos(p, t, buf, 0);
    if (f <= up_down_pos) l = t; else r = t-1;
  }
  int j = l-value();
  j = position(j, keepmark ? mark_ : j);
  was_up_down = 1;
  return j;
}

/**
  Put the current selection between mark() and
  position() into the specified clipboard.  Does not
  replace the old clipboard contents if position() and
  mark() are equal. Clipboard 0 maps to the current text
  selection and clipboard 1 maps to the cut/paste clipboard.
*/
int Fl_Input_::copy(int clipboard) {
  int b = position();
  int e = mark();
  if (b != e) {
    if (b > e) {b = mark(); e = position();}
    if (input_type() == FL_SECRET_INPUT) e = b;
    Fl::copy(value()+b, e-b, clipboard);
    return 1;
  }
  return 0;
}

#define MAXFLOATSIZE 40

static char* undobuffer;
static int undobufferlength;
static Fl_Input_* undowidget;
static int undoat;	// points after insertion
static int undocut;	// number of characters deleted there
static int undoinsert;	// number of characters inserted
static int yankcut;	// length of valid contents of buffer, even if undocut=0

static void undobuffersize(int n) {
  if (n > undobufferlength) {
    if (undobuffer) {
      do {undobufferlength *= 2;} while (undobufferlength < n);
      undobuffer = (char*)realloc(undobuffer, undobufferlength);
    } else {
      undobufferlength = n+9;
      undobuffer = (char*)malloc(undobufferlength);
    }
  }
}

// all changes go through here, delete characters b-e and insert text:
/**
  This call does all editing of the text. It deletes the region
  between a and b (either one may be less or
  equal to the other), and then inserts the string insert
  at that point and leaves the mark() and
  position() after the insertion. Does the callback if
  when() & FL_WHEN_CHANGED and there is a change.
  
  <P>Set start and end equal to not delete
  anything. Set insert to NULL to not insert
  anything.</P>
  
  <P>length must be zero or strlen(insert), this
  saves a tiny bit of time if you happen to already know the
  length of the insertion, or can be used to insert a portion of a
  string or a string containing nul's.</P>
  
  <P>a and b are clamped to the
  0..size() range, so it is safe to pass any values.</P>
  
  <P>cut() and insert() are just inline
  functions that call replace().
*/
int Fl_Input_::replace(int b, int e, const char* text, int ilen) {
  int ul, om, op;
  was_up_down = 0;

  if (b<0) b = 0;
  if (e<0) e = 0;
  if (b>size_) b = size_;
  if (e>size_) e = size_;
  if (e<b) {int t=b; b=e; e=t;}
  while (b != e && b > 0 && (size_ - b) > 0 &&
       (fl_utf8len((value_ + b)[0]) < 1)) { b--; }
  ul = fl_utf8len((char)(value_ + e)[0]);
  while (e < size_ && e > 0 && ul < 0) {
       e++;
       ul = fl_utf8len((char)(value_ + e)[0]);
  }
  if (text && !ilen) ilen = strlen(text);
  if (e<=b && !ilen) return 0; // don't clobber undo for a null operation
  if (size_+ilen-(e-b) > maximum_size_) {
    ilen = maximum_size_-size_+(e-b);
    if (ilen < 0) ilen = 0;
  }

  put_in_buffer(size_+ilen);

  if (e>b) {
    if (undowidget == this && b == undoat) {
      undobuffersize(undocut+(e-b));
      memcpy(undobuffer+undocut, value_+b, e-b);
      undocut += e-b;
    } else if (undowidget == this && e == undoat && !undoinsert) {
      undobuffersize(undocut+(e-b));
      memmove(undobuffer+(e-b), undobuffer, undocut);
      memcpy(undobuffer, value_+b, e-b);
      undocut += e-b;
    } else if (undowidget == this && e == undoat && (e-b)<undoinsert) {
      undoinsert -= e-b;
    } else {
      undobuffersize(e-b);
      memcpy(undobuffer, value_+b, e-b);
      undocut = e-b;
      undoinsert = 0;
    }
    memmove(buffer+b, buffer+e, size_-e+1);
    size_ -= e-b;
    undowidget = this;
    undoat = b;
    if (input_type() == FL_SECRET_INPUT) yankcut = 0; else yankcut = undocut;
  }

  if (ilen) {
    if (undowidget == this && b == undoat)
      undoinsert += ilen;
    else {
      undocut = 0;
      undoinsert = ilen;
    }
    memmove(buffer+b+ilen, buffer+b, size_-b+1);
    memcpy(buffer+b, text, ilen);
    size_ += ilen;
  }
  undowidget = this;
  om = mark_;
  op = position_;
  mark_ = position_ = undoat = b+ilen;

  // Insertions into the word at the end of the line will cause it to
  // wrap to the next line, so we must indicate that the changes may start
  // right after the whitespace before the current word.  This will
  // result in sub-optimal update when such wrapping does not happen
  // but it is too hard to figure out for now...
  if (wrap()) {
    // if there is a space in the pasted text, the whole line may have rewrapped
    int i;
    for (i=0; i<ilen; i++)
      if (text[i]==' ') break;
    if (i==ilen)
      while (b > 0 && !isspace(index(b) & 255) && index(b)!='\n') b--;
    else
      while (b > 0 && index(b)!='\n') b--;
  }

  // make sure we redraw the old selection or cursor:
  if (om < b) b = om;
  if (op < b) b = op;

  minimal_update(b);

  mark_ = position_ = undoat;

  set_changed();
  if (when()&FL_WHEN_CHANGED) do_callback();
  return 1;
}

/**
  Does undo of several previous calls to replace().
  Returns non-zero if any change was made.
*/
int Fl_Input_::undo() {
  was_up_down = 0;
  if (undowidget != this || !undocut && !undoinsert) return 0;

  int ilen = undocut;
  int xlen = undoinsert;
  int b = undoat-xlen;
  int b1 = b;

  put_in_buffer(size_+ilen);

  if (ilen) {
    memmove(buffer+b+ilen, buffer+b, size_-b+1);
    memcpy(buffer+b, undobuffer, ilen);
    size_ += ilen;
    b += ilen;
  }

  if (xlen) {
    undobuffersize(xlen);
    memcpy(undobuffer, buffer+b, xlen);
    memmove(buffer+b, buffer+b+xlen, size_-xlen-b+1);
    size_ -= xlen;
  }

  undocut = xlen;
  if (xlen) yankcut = xlen;
  undoinsert = ilen;
  undoat = b;
  mark_ = b /* -ilen */;
  position_ = b;

  if (wrap())
    while (b1 > 0 && index(b1)!='\n') b1--;
  minimal_update(b1);
  set_changed();
  if (when()&FL_WHEN_CHANGED) do_callback();
  return 1;
}

/**
  Copy all the previous contiguous cuts from the undo
  information to the clipboard. This is used to make ^K work.
*/
int Fl_Input_::copy_cuts() {
  // put the yank buffer into the X clipboard
  if (!yankcut || input_type()==FL_SECRET_INPUT) return 0;
  Fl::copy(undobuffer, yankcut, 1);
  return 1;
}

void Fl_Input_::maybe_do_callback() {
  if (changed() || (when()&FL_WHEN_NOT_CHANGED)) {
    do_callback();
  }
}

int Fl_Input_::handletext(int event, int X, int Y, int W, int H) {
  switch (event) {

  case FL_ENTER:
  case FL_MOVE:
    if (active_r() && window()) window()->cursor(FL_CURSOR_INSERT);
    return 1;

  case FL_LEAVE:
    if (active_r() && window()) window()->cursor(FL_CURSOR_DEFAULT);
    return 1;

  case FL_FOCUS:
    fl_set_spot(textfont(), textsize(), x(), y(), w(), h(), window());
    if (mark_ == position_) {
      minimal_update(size()+1);
    } else //if (Fl::selection_owner() != this)
      minimal_update(mark_, position_);
    return 1;

  case FL_UNFOCUS:
    if (active_r() && window()) window()->cursor(FL_CURSOR_DEFAULT);
    if (mark_ == position_) {
      if (!(damage()&FL_DAMAGE_EXPOSE)) {minimal_update(position_); erase_cursor_only = 1;}
    } else //if (Fl::selection_owner() != this)
      minimal_update(mark_, position_);
  case FL_HIDE:
    fl_reset_spot();
    if (!readonly() && (when() & FL_WHEN_RELEASE))
      maybe_do_callback();
    return 1;

  case FL_PUSH:
    if (active_r() && window()) window()->cursor(FL_CURSOR_INSERT);

    handle_mouse(X, Y, W, H, Fl::event_state(FL_SHIFT));

    if (Fl::focus() != this) {
      Fl::focus(this);
      handle(FL_FOCUS);
    }
    return 1;

  case FL_DRAG:
    handle_mouse(X, Y, W, H, 1);
    return 1;

  case FL_RELEASE:
    copy(0);
    return 1;

  case FL_PASTE: {
    // Don't allow pastes into readonly widgets...
    if (readonly()) {
      fl_beep(FL_BEEP_ERROR);
      return 1;
    }

    // See if we have anything to paste...
    if (!Fl::event_text() || !Fl::event_length()) return 1;

    // strip trailing control characters and spaces before pasting:
    const char* t = Fl::event_text();
    const char* e = t+Fl::event_length();
    if (input_type() != FL_MULTILINE_INPUT) while (e > t && isspace(*(e-1) & 255)) e--;
    if (!t || e <= t) return 1; // Int/float stuff will crash without this test
    if (input_type() == FL_INT_INPUT) {
      while (isspace(*t & 255) && t < e) t ++;
      const char *p = t;
      if (*p == '+' || *p == '-') p ++;
      if (strncmp(p, "0x", 2) == 0) {
        p += 2;
        while (isxdigit(*p & 255) && p < e) p ++;
      } else {
        while (isdigit(*p & 255) && p < e) p ++;
      }
      if (p < e) {
        fl_beep(FL_BEEP_ERROR);
        return 1;
      } else return replace(0, size(), t, e - t);
    } else if (input_type() == FL_FLOAT_INPUT) {
      while (isspace(*t & 255) && t < e) t ++;
      const char *p = t;
      if (*p == '+' || *p == '-') p ++;
      while (isdigit(*p & 255) && p < e) p ++;
      if (*p == '.') {
        p ++;
        while (isdigit(*p & 255) && p < e) p ++;
	if (*p == 'e' || *p == 'E') {
	  p ++;
	  if (*p == '+' || *p == '-') p ++;
	  while (isdigit(*p & 255) && p < e) p ++;
	}
      }
      if (p < e) {
        fl_beep(FL_BEEP_ERROR);
        return 1;
      } else return replace(0, size(), t, e - t);
    }
    return replace(position(), mark(), t, e-t);}

  case FL_SHORTCUT:
    if (!(shortcut() ? Fl::test_shortcut(shortcut()) : test_shortcut())) 
      return 0;
    if (Fl::visible_focus() && handle(FL_FOCUS)) {
      Fl::focus(this);
      return 1;
    } // else fall through

  default:
    return 0;
  }
}

/*------------------------------*/

/**
  Creates a new Fl_Input_ widget using the given
  position, size, and label string. The default boxtype is
  FL_DOWN_BOX.
*/
Fl_Input_::Fl_Input_(int X, int Y, int W, int H, const char* l)
: Fl_Widget(X, Y, W, H, l) {
  box(FL_DOWN_BOX);
  color(FL_BACKGROUND2_COLOR, FL_SELECTION_COLOR);
  align(FL_ALIGN_LEFT);
  textsize_ = FL_NORMAL_SIZE;
  textfont_ = FL_HELVETICA;
  textcolor_ = FL_FOREGROUND_COLOR;
  cursor_color_ = FL_FOREGROUND_COLOR; // was FL_BLUE
  mark_ = position_ = size_ = 0;
  bufsize = 0;
  buffer  = 0;
  value_ = "";
  xscroll_ = yscroll_ = 0;
  maximum_size_ = 32767;
  shortcut_ = 0;
  set_flag(SHORTCUT_LABEL);
}

void Fl_Input_::put_in_buffer(int len) {
  if (value_ == buffer && bufsize > len) {
    buffer[size_] = 0;
    return;
  }
  if (!bufsize) {
    if (len > size_) len += 9; // let a few characters insert before realloc
    bufsize = len+1; 
    buffer = (char*)malloc(bufsize);
  } else if (bufsize <= len) {
    // we may need to move old value in case it points into buffer:
    int moveit = (value_ >= buffer && value_ < buffer+bufsize);
    // enlarge current buffer
    if (len > size_) {
      do {bufsize *= 2;} while (bufsize <= len);
    } else {
      bufsize = len+1;
    }
    // Note: the following code is equivalent to:
    //
    //   if (moveit) value_ = value_ - buffer;
    //   char* nbuffer = (char*)realloc(buffer, bufsize);
    //   if (moveit) value_ = value_ + nbuffer;
    //   buffer = nbuffer;
    //
    // We just optimized the pointer arithmetic for value_...
    //
    char* nbuffer = (char*)realloc(buffer, bufsize);
    if (moveit) value_ += (nbuffer-buffer);
    buffer = nbuffer;
  }
  memmove(buffer, value_, size_); buffer[size_] = 0;
  value_ = buffer;
}
/** See int Fl_Input::static_value(const char*) */
int Fl_Input_::static_value(const char* str, int len) {
  clear_changed();
  if (undowidget == this) undowidget = 0;
  if (str == value_ && len == size_) return 0;
  if (len) { // non-empty new value:
    if (xscroll_ || yscroll_) {
      xscroll_ = yscroll_ = 0;
      minimal_update(0);
    } else {
      int i = 0;
      // find first different character:
      if (value_) {
	for (; i<size_ && i<len && str[i]==value_[i]; i++);
	if (i==size_ && i==len) return 0;
      }
      minimal_update(i);
    }
    value_ = str;
    size_ = len;
  } else { // empty new value:
    if (!size_) return 0; // both old and new are empty.
    size_ = 0;
    value_ = "";
    xscroll_ = yscroll_ = 0;
    minimal_update(0);
  }
  position(readonly() ? 0 : size());
  return 1;
}

/**
  Change the text and set the mark and the point to the end of
  it. The string is <I>not</I> copied. If the user edits the
  string it is copied to the internal buffer then. This can save a
  great deal of time and memory if your program is rapidly
  changing the values of text fields, but this will only work if
  the passed string remains unchanged until either the
  Fl_Input is destroyed or value() is called
  again.
*/
int Fl_Input_::static_value(const char* str) {
  return static_value(str, str ? strlen(str) : 0);
}
/** See const char *Fl_Input_::value() const */
int Fl_Input_::value(const char* str, int len) {
  int r = static_value(str, len);
  if (len) put_in_buffer(len);
  return r;
}

/** See const char *Fl_Input_::value() const */
int Fl_Input_::value(const char* str) {
  return value(str, str ? strlen(str) : 0);
}

void Fl_Input_::resize(int X, int Y, int W, int H) {
  if (W != w()) xscroll_ = 0;
  if (H != h()) yscroll_ = 0;
  Fl_Widget::resize(X, Y, W, H);
}

Fl_Input_::~Fl_Input_() {
  if (undowidget == this) undowidget = 0;
  if (bufsize) free((void*)buffer);
}

//
// End of "$Id$".
//