/* ************************************************************************

   qooxdoo - the new era of web development

   http://qooxdoo.org

   Copyright:
     2004-2007 1&1 Internet AG, Germany, http://www.1and1.org
     2006 STZ-IDA, Germany, http://www.stz-ida.de

   License:
     LGPL: http://www.gnu.org/licenses/lgpl.html
     EPL: http://www.eclipse.org/org/documents/epl-v10.php
     See the LICENSE file in the project's top-level directory for details.

   Authors:
     * Sebastian Werner (wpbasti)
     * Andreas Ecker (ecker)
     * Andreas Junghans (lucidcake)

************************************************************************ */

/* ************************************************************************

#module(ui_core)
#require(qx.core.Client)

************************************************************************ */

qx.OO.defineClass("qx.html.StyleSheet");

/**
 * Include a CSS file
 *
 * @param vHref {String} Href value
 */
qx.html.StyleSheet.includeFile = function(vHref)
{
  var el = document.createElement("link");
  el.type = "text/css";
  el.rel = "stylesheet";
  el.href = vHref;

  var head = document.getElementsByTagName("head")[0];
  head.appendChild(el);
};

/**
 * create a new Stylesheet node and append it to the document
 *
 * @param vCssText {String} optional string of css rules
 */
qx.html.StyleSheet.createElement = function(vCssText) {};
if (document.createStyleSheet) // IE 4+
{
  qx.html.StyleSheet.createElement = function(vCssText)
  {
    var vSheet = document.createStyleSheet();

    if (vCssText) {
      vSheet.cssText = vCssText;
    }

    return vSheet;
  };
}
else // FF, Opera, Safari
{
  qx.html.StyleSheet.createElement = function(vCssText)
  {
    var vElement = document.createElement("style");
    vElement.type = "text/css";

    // Safari 2.0 doesn't like empty stylesheets
    vElement.appendChild(document.createTextNode(vCssText || "body {}"));

    document.getElementsByTagName("head")[0].appendChild(vElement);

    if (vElement.sheet) {
      return vElement.sheet;
    } else {
      // Safari 2.0 doesn't support element.sheet so we neet a workaround
      var styles = document.styleSheets;
      for (var i=styles.length-1; i>=0; i--) {
        if (styles[i].ownerNode == vElement) {
          return styles[i];
        }
      }
    }
    throw "Error: Could not get a reference to the sheet object";
  };
}


/**
 * insert a new CSS rule into a given Stylesheet
 *
 * @param vSheet {Object} the target Stylesheet object
 * @param vSelector {String} the selector
 * @param vStyle {String} style rule
 */
qx.html.StyleSheet.addRule = function(vSheet, vSelector, vStyle) {};
if (document.createStyleSheet) // IE 4+
{
  qx.html.StyleSheet.addRule = function(vSheet, vSelector, vStyle) {
    vSheet.addRule(vSelector, vStyle);
  };
}
else if (qx.core.Client.getInstance().isSafari2()) // insertRule in Safari 2 doesn't work
{
  qx.html.StyleSheet.addRule = function(vSheet, vSelector, vStyle) {
    if (!vSheet._qxRules) {
      vSheet._qxRules = {};
    }
    if (!vSheet._qxRules[vSelector]) {
      var ruleNode = document.createTextNode(vSelector + "{" + vStyle + "}");
      vSheet.ownerNode.appendChild(ruleNode);
      vSheet._qxRules[vSelector] = ruleNode;
    }
  };
}
else // FF, Opera
{
  qx.html.StyleSheet.addRule = function(vSheet, vSelector, vStyle) {
    vSheet.insertRule(vSelector + "{" + vStyle + "}", vSheet.cssRules.length);
  };
}


/**
 * remove a CSS rule from a stylesheet
 *
 * @param vSheet     {Object} the Stylesheet
 * @param vSelector {String} the Selector of the rule to remove
 */
qx.html.StyleSheet.removeRule = function(vSheet, vSelector) {};
if (document.createStyleSheet) // IE 4+
{
  qx.html.StyleSheet.removeRule = function(vSheet, vSelector)
  {
    var vRules = vSheet.rules;
    var vLength = vRules.length;

    for (var i=vLength-1; i>=0; i--)
    {
      if (vRules[i].selectorText == vSelector) {
        vSheet.removeRule(i);
      }
    }
  };
}
else if (qx.core.Client.getInstance().isSafari2()) // removeRule in Safari 2 doesn't work
{
  qx.html.StyleSheet.removeRule = function(vSheet, vSelector)
  {
    var warn = function() {
      qx.log.Logger.ROOT_LOGGER.warn("In Safari/Webkit you can only remove rules that are created using qx.html.StyleSheet.addRule");
    }
    if (!vSheet._qxRules) {
      warn();
    }
    var ruleNode = vSheet._qxRules[vSelector];
    if (ruleNode) {
      vSheet.ownerNode.removeChild(ruleNode);
      vSheet._qxRules[vSelector] = null;
    } else {
      warn();
    }
  };
}
else
{
  qx.html.StyleSheet.removeRule = function(vSheet, vSelector)
  {
    var vRules = vSheet.cssRules;
    var vLength = vRules.length;

    for (var i=vLength-1; i>=0; i--)
    {
      if (vRules[i].selectorText == vSelector) {
        vSheet.deleteRule(i);
      }
    }
  };
}


/**
 * remove all CSS rules from a stylesheet
 *
 * @param vSheet {Object} the stylesheet object
 */
qx.html.StyleSheet.removeAllRules = function(vSheet) {};
if (document.createStyleSheet) // IE 4+
{
  qx.html.StyleSheet.removeAllRules = function(vSheet)
  {
    var vRules = vSheet.rules;
    var vLength = vRules.length;

    for (var i=vLength-1; i>=0; i--) {
      vSheet.removeRule(i);
    }
  };
}
else if (qx.core.Client.getInstance().isSafari2()) // removeRule in Safari 2 doesn't work
{
  qx.html.StyleSheet.removeAllRules = function(vSheet)
  {
    var node = vSheet.ownerNode;
    var rules = node.childNodes;
    while (rules.length > 0) {
      node.removeChild(rules[0]);
    }
  };
}
else // FF, etc
{
  qx.html.StyleSheet.removeAllRules = function(vSheet)
  {
    var vRules = vSheet.cssRules;
    var vLength = vRules.length;

    for (var i=vLength-1; i>=0; i--) {
      vSheet.deleteRule(i);
    }
  };
}



// TODO import functions are not working crossbrowser (Safari) !!
// see CSS_1.html test

/**
 * add an import of an external CSS file to a stylesheet
 * @param vSheet {Object} the stylesheet object
 * @param vUrl {String} URL of the external stylesheet file
 */
qx.html.StyleSheet.addImport = function(vSheet, vUrl) {};
if (document.createStyleSheet) // IE 4+
{
  qx.html.StyleSheet.addImport = function(vSheet, vUrl) {
    vSheet.addImport(vUrl);
  };
}
else  if (qx.core.Client.getInstance().isSafari2()) // insertRule in Safari 2 doesn't work
{
  qx.html.StyleSheet.addImport = function(vSheet, vUrl) {
    vSheet.ownerNode.appendChild(document.createTextNode('@import "' + vUrl + '";'));
  };
}
else // FF, etc
{
  qx.html.StyleSheet.addImport = function(vSheet, vUrl) {
    vSheet.insertRule('@import "' + vUrl + '";', vSheet.cssRules.length);
  };
}


/**
 * removes an import from a stylesheet
 *
 * @param vSheet {Object} the stylesheet object
 * @param vUrl {String}  URL of the importet CSS file
 */
qx.html.StyleSheet.removeImport = function(vSheet, vUrl) {};
if (document.createStyleSheet) // IE 4+
{
  qx.html.StyleSheet.removeImport = function(vSheet, vUrl) {
    var vImports = vSheet.imports;
    var vLength = vImports.length;

    for (var i=vLength-1; i>=0; i--) {
      if (vImports[i].href == vUrl) {
        vSheet.removeImport(i);
      }
    }
  };
}
else // FF, etc
{
  qx.html.StyleSheet.removeImport = function(vSheet, vUrl) {
    var vRules = vSheet.cssRules;
    var vLength = vRules.length;

    for (var i=vLength-1; i>=0; i--) {
      if (vRules[i].href == vUrl) {
        vSheet.deleteRule(i);
      }
    }
  };
}


/**
 * remove all imports from a stylesheet
 *
 * @param vSheet {Object} the stylesheet object
 */
qx.html.StyleSheet.removeAllImports = function(vSheet) {};
if (document.createStyleSheet) // IE 4+
{
  qx.html.StyleSheet.removeAllImports = function(vSheet) {
    var vImports = vSheet.imports;
    var vLength = vImports.length;

    for (var i=vLength-1; i>=0; i--) {
      vSheet.removeImport(i);
    }
  };
}
else // FF, etc
{
  qx.html.StyleSheet.removeAllImports = function(vSheet) {
    var vRules = vSheet.cssRules;
    var vLength = vRules.length;

    for (var i=vLength-1; i>=0; i--) {
      if (vRules[i].type == vRules[i].IMPORT_RULE) {
        vSheet.deleteRule(i);
      }
    }
  };
}