/**************************************************
 * dom-drag.js
 * 09.25.2001
 * www.youngpup.net
 **************************************************/
document.dragger = null;
Drag = function () {
  this.id = 'Drag';
  obj: null,

  //  -------------------------------------------------------------------------
  this.init = function (oId, oRootId, fXMapper, fYMapper) {
//    alert ('now init ('+oId+', '+oRootId+', '+minX+', '+maxX+', '+minY+', '+maxY+', '+bSwapHorzRef+', '+bSwapVertRef+', '+fXMapper+', '+fYMapper+')');
    var o = nodeOf(oId); if (!o) return;
    var oRoot = nodeOf(oRootId); if (!oRoot) return;
    oRoot.dragger = this;  // store the object locally in the embedding container
    o.onmousedown = oRoot.dragger.start;

//    oRoot.showAttributes ();

    o.root = oRoot && oRoot !== null ? oRoot : o;
    o.xMapper = fXMapper ? fXMapper : null;
    o.yMapper = fYMapper ? fYMapper : null;

    o.root.onDragStart = new Function();
    o.root.onDragEnd = new Function();
    o.root.onDrag = new Function();
//    alert ('dragger='+document.dragger.id);
  };

  //  -------------------------------------------------------------------------
  this.start = function (e) {
//    alert ('now start ('+e+')');
    document.dragger = this.parentNode.dragger;
    var o = document.dragger.obj = this;

//  insertInspect (oRoot, 'oRoot', 2, 0)
//  alert ('left: '+o.root.getStyleFromCSS('left')+'\n'+'top: '+o.root.getStyleFromCSS('top')+'\n'+'bottom: '+o.root.getStyleFromCSS('bottom')); 

    o.root.style.left   = o.root.style.left.length   ? o.root.style.left   : o.root.getStyleFromCSS('left');
    o.root.style.top    = o.root.style.top.length    ? o.root.style.top    : o.root.getStyleFromCSS('top');
    o.root.style.right  = o.root.style.right.length  ? o.root.style.right  : o.root.getStyleFromCSS('right');
    o.root.style.bottom = o.root.style.bottom.length ? o.root.style.bottom : o.root.getStyleFromCSS('bottom');

    o.hmode = !!o.root.style.left.length;
    o.vmode = !!o.root.style.top.length;

    o.minX = null;
    o.minY = null;
    o.maxX = null;
    o.maxY = null;

//    o.parentNode.showAttributes ();

    e = fixEvent(e);
    var y = parseInt(o.vmode ? o.root.style.top : o.root.style.bottom, 10);
    var x = parseInt(o.hmode ? o.root.style.left : o.root.style.right, 10);
    o.root.onDragStart(x, y);

    o.lastMouseX = e.clientX;
    o.lastMouseY = e.clientY;

    if (o.hmode) {
      if (o.minX !== null) {o.minMouseX = e.clientX - x + o.minX;}
      if (o.maxX !== null) {o.maxMouseX = o.minMouseX + o.maxX - o.minX;}
    } else {
      if (o.minX !== null) {o.maxMouseX = -o.minX + e.clientX + x;}
      if (o.maxX !== null) {o.minMouseX = -o.maxX + e.clientX + x;}
    }

    if (o.vmode) {
      if (o.minY !== null) {o.minMouseY = e.clientY - y + o.minY;}
      if (o.maxY !== null) {o.maxMouseY = o.minMouseY + o.maxY - o.minY;}
    } else {
      if (o.minY !== null) {o.maxMouseY = -o.minY + e.clientY + y;}
      if (o.maxY !== null) {o.minMouseY = -o.maxY + e.clientY + y;}
    }

    document.onmousemove = document.dragger.drag;
    document.onmouseup = document.dragger.end;

    return false;
  };

  //  -------------------------------------------------------------------------
  this.drag = function (e) {
//    alert (this.id+'.drag ('+e+')');
    e = fixEvent(e);
    var o = document.dragger.obj;

    var ey = e.clientY;
    var ex = e.clientX;
    var y = parseInt(o.vmode ? o.root.style.top  : o.root.style.bottom, 10);
    var x = parseInt(o.hmode ? o.root.style.left : o.root.style.right , 10);
    var nx, ny;

    if (o.minX !== null) {ex = o.hmode ? Math.max(ex, o.minMouseX) : Math.min(ex, o.maxMouseX);}
    if (o.maxX !== null) {ex = o.hmode ? Math.min(ex, o.maxMouseX) : Math.max(ex, o.minMouseX);}
    if (o.minY !== null) {ey = o.vmode ? Math.max(ey, o.minMouseY) : Math.min(ey, o.maxMouseY);}
    if (o.maxY !== null) {ey = o.vmode ? Math.min(ey, o.maxMouseY) : Math.max(ey, o.minMouseY);}

    nx = x + ((ex - o.lastMouseX) * (o.hmode ? 1 : -1));
    ny = y + ((ey - o.lastMouseY) * (o.vmode ? 1 : -1));

    if (o.xMapper) {nx = o.xMapper(y);}
    else if (o.yMapper) {ny = o.yMapper(x);}

    document.dragger.obj.root.style[o.hmode ? "left" : "right"] = nx + "px";
    document.dragger.obj.root.style[o.vmode ? "top" : "bottom"] = ny + "px";
    document.dragger.obj.lastMouseX = ex;
    document.dragger.obj.lastMouseY = ey;

    document.dragger.obj.root.onDrag(nx, ny);
    return false;
  };

  //  -------------------------------------------------------------------------
  this.end = function () {
//    alert (this.id+'.end (), dragger='+document.dragger.id);
    document.onmousemove = null;
    document.onmouseup = null;
    document.dragger.obj.root.onDragEnd(parseInt(document.dragger.obj.root.style[document.dragger.obj.hmode ? "left" : "right"], 10), parseInt(document.dragger.obj.root.style[document.dragger.obj.vmode ? "top" : "bottom"], 10));
    document.dragger.obj = null;
    document.dragger = null;
  };

  //  -------------------------------------------------------------------------
};

//  --------------------------------------------------------------------------