package ZincText;


sub new {
  my $proto = shift;
  my $type = ref($proto) || $proto;
  my ($zinc) = @_;
  my $self = {};

  $zinc->bind('text', '<1>' => sub {startSel($zinc)});
  $zinc->bind('text', '<2>' => sub {pasteSel($zinc)});
  $zinc->bind('text', '<B1-Motion>' => sub {extendSel($zinc)});
  $zinc->bind('text', '<Shift-B1-Motion>' => sub {extendSel($zinc)});
  $zinc->bind('text', '<Shift-1>' => sub {
		my $e = $zinc->XEvent();
		my($x, $y) = ($e->x, $e->y);
		$zinc->select('adjust', 'current', "\@$x,$y"); });
  $zinc->bind('text', '<Left>' => sub {moveCur($zinc, -1);});
  $zinc->bind('text', '<Right>' => sub {moveCur($zinc, 1);});
  $zinc->bind('text', '<Up>' => sub {setCur($zinc, 'up');});
  $zinc->bind('text', '<Down>' => sub {setCur($zinc, 'down');});
  $zinc->bind('text', '<Control-a>' => sub {setCur($zinc, 'bol');});
  $zinc->bind('text', '<Home>' => sub {setCur($zinc, 'bol');});
  $zinc->bind('text', '<Control-e>' => sub {setCur($zinc, 'eol');});
  $zinc->bind('text', '<End>' => sub {setCur($zinc, 'eol');});
  $zinc->bind('text', '<Meta-less>' => sub {setCur($zinc, 0);});
  $zinc->bind('text', '<Meta-greater>' => sub {setCur($zinc, 'end');});
  $zinc->bind('text', '<KeyPress>' => sub {insertKey($zinc);});
  $zinc->bind('text', '<Shift-KeyPress>' => sub {insertKey($zinc);});
  $zinc->bind('text', '<Return>' => sub { insertChar($zinc, chr(10)); });
  $zinc->bind('text', '<BackSpace>' => sub {textDel($zinc, -1)});
  $zinc->bind('text', '<Control-h>' => sub {textDel($zinc, -1)});
  $zinc->bind('text', '<Delete>' => sub {textDel($zinc, 0)});

  bless ($self, $type);
  return $self;
}


sub pasteSel {
  my ($w) = @_;
  my $e = $w->XEvent;
  my($x, $y) = ($e->x(), $e->y());
  my @it = $w->focus();

  if (@it != 0) {
    eval { $w->insert(@it, "\@$x,$y", $w->SelectionGet()); };
  }
}


sub insertChar {
  my ($w, $c) = @_;
  my @it = $w->focus();
  my @selit = $w->select('item');

  if (@it == 0) {
    return;
  }

  if ((scalar(@selit) == scalar(@it)) &&
      ($selit[0] == $it[0]) && ($selit[1] == $it[1])) {
    $w->dchars(@it, 'sel.first', 'sel.last');
  }
  $w->insert(@it, 'insert', $c);
}


sub insertKey {
  my ($w) = @_;
  my $c = $w->XEvent->A();

  if ((ord($c) < 32) || (ord($c) == 128)) {
    return;
  }

  insertChar($w, $c);
}


sub setCur {
  my ($w, $where) = @_;
  my @it = $w->focus();

  if (@it != 0) {
    $w->cursor(@it, $where);
  }
}


sub moveCur {
  my ($w, $dir) = @_;
  my @it = $w->focus();
  my $index;

  if (@it != 0) {
    $index = $w->index(@it, 'insert');
    $w->cursor(@it, $index + $dir);
  }
}


sub startSel {
  my($w) = @_;
  my $e = $w->XEvent;
  my($x, $y) = ($e->x(), $e->y());
  my $part = $w->currentpart(1);

  $w->cursor('current', $part, "\@$x,$y");
  $w->focus('current', $part);
  $w->Tk::focus();
  $w->select('from', 'current', $part, "\@$x,$y");
}


sub extendSel {
  my($w) = @_;
  my $e = $w->XEvent;
  my($x, $y) = ($e->x, $e->y);
  my $part = $w->currentpart(1);

  $w->select('to', 'current', $part, "\@$x,$y");
}


sub textDel {
  my($w, $dir) = @_;
  my @it = $w->focus();
  my @selit = $w->select('item');
  my $ind;

  if (@it == 0) {
    return;
  }

  if ((scalar(@selit) == scalar(@it)) &&
      ($selit[0] == $it[0]) && ($selit[1] == $it[1])) {
    $w->dchars(@it, 'sel.first', 'sel.last');
  }
  else {
    $ind = $w->index(@it, 'insert') + $dir;
    $w->dchars(@it, $ind, $ind) if ($ind >= 0);
  }
}

1;