/*

  * Licensed to the Apache Software Foundation (ASF) under one

  * or more contributor license agreements.  See the NOTICE file

  * distributed with this work for additional information

  * regarding copyright ownership.  The ASF licenses this file

  * to you under the Apache License, Version 2.0 (the

  * "License"); you may not use this file except in compliance

  * with the License.  You may obtain a copy of the License at

  *

  *   http://www.apache.org/licenses/LICENSE-2.0

  *

  * Unless required by applicable law or agreed to in writing,

  * software distributed under the License is distributed on an

  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY

  * KIND, either express or implied.  See the License for the

  * specific language governing permissions and limitations

  * under the License.

  */

 package org.apache.myfaces.shared.renderkit.html;

 import java.io.IOException;

 import java.util.Iterator;

 import java.util.Map;

 import java.util.Set;

 import java.util.logging.Logger;

 import javax.faces.context.ExternalContext;

 import javax.faces.context.FacesContext;

 import javax.faces.context.ResponseWriter;

 import org.apache.myfaces.shared.config.MyfacesConfig;

 import org.apache.myfaces.shared.renderkit.html.HtmlRendererUtils.ScriptContext;

 import org.apache.myfaces.shared.renderkit.html.util.JavascriptUtils;

 import org.apache.myfaces.shared.renderkit.html.util.ResourceUtils;

 public final class HtmlJavaScriptUtils

 {

     private static final Logger log = Logger.getLogger(HtmlJavaScriptUtils.class

             .getName());

     private static final String AUTO_SCROLL_PARAM = "autoScroll";

     private static final String AUTO_SCROLL_FUNCTION = "getScrolling";

     private static final String SET_HIDDEN_INPUT_FN_NAME = "oamSetHiddenInput";

     private static final String SET_HIDDEN_INPUT_FN_NAME_JSF2 = "myfaces.oam.setHiddenInput";

     private static final String FIRST_SUBMIT_SCRIPT_ON_PAGE = "org.apache.MyFaces.FIRST_SUBMIT_SCRIPT_ON_PAGE";

     private static final String CLEAR_HIDDEN_INPUT_FN_NAME = "oamClearHiddenInput";

     @SuppressWarnings("unchecked")

     public static void renderFormSubmitScript(FacesContext facesContext)

             throws IOException

     {

         if (facesContext.getPartialViewContext() != null && 

                 (facesContext.getPartialViewContext().isPartialRequest() ||

                  facesContext.getPartialViewContext().isAjaxRequest() )

             )

         {

             return;

         }

         Map map = facesContext.getExternalContext().getRequestMap();

         Boolean firstScript = (Boolean) map.get(FIRST_SUBMIT_SCRIPT_ON_PAGE);

         if (firstScript == null || firstScript.equals(Boolean.TRUE))

         {

             map.put(FIRST_SUBMIT_SCRIPT_ON_PAGE, Boolean.FALSE);

             renderFormSubmitScriptIfNecessary(facesContext);

             //we have to render the config just in case

             renderConfigOptionsIfNecessary(facesContext);

         }

     }

     /**

      * @param facesContext

      * @throws IOException

      */

     private static void renderFormSubmitScriptIfNecessary(

             FacesContext facesContext) throws IOException

     {

         ResponseWriter writer = facesContext.getResponseWriter();

         ResourceUtils

                 .renderMyfacesJSInlineIfNecessary(facesContext, writer);

     }

     private static void renderConfigOptionsIfNecessary(FacesContext facesContext)

             throws IOException

     {

         ResponseWriter writer = facesContext.getResponseWriter();

         MyfacesConfig config = MyfacesConfig.getCurrentInstance(facesContext

                 .getExternalContext());

         ScriptContext script = new ScriptContext();

         boolean autoScroll = config.isAutoScroll();

         boolean autoSave = JavascriptUtils.isSaveFormSubmitLinkIE(facesContext

                 .getExternalContext());

         if (autoScroll || autoSave)

         {

             script.prettyLine();

             script.increaseIndent();

             script.append("(!window.myfaces) ? window.myfaces = {} : null;");

             script.append("(!myfaces.core) ? myfaces.core = {} : null;");

             script.append("(!myfaces.core.config) ? myfaces.core.config = {} : null;");

         }

         if (autoScroll)

         {

             script.append("myfaces.core.config.autoScroll = true;");

         }

         if (autoSave)

         {

             script.append("myfaces.core.config.ieAutoSave = true;");

         }

         if (autoScroll || autoSave)

         {

             writer.startElement(HTML.SCRIPT_ELEM, null);

             writer.writeAttribute(HTML.TYPE_ATTR, "text/javascript", null);

             writer.writeText(script.toString(), null);

             writer.endElement(HTML.SCRIPT_ELEM);

         }

     }

     public static void appendAutoScrollAssignment(StringBuilder onClickValue,

             String formName)

     {

         appendAutoScrollAssignment(FacesContext.getCurrentInstance(),

                 new ScriptContext(onClickValue, false), formName);

     }

     /**

      * Adds the hidden form input value assignment that is necessary for the autoscroll

      * feature to an html link or button onclick attribute.

      */

     public static void appendAutoScrollAssignment(FacesContext context,

             StringBuilder onClickValue, String formName)

     {

         appendAutoScrollAssignment(context, new ScriptContext(onClickValue,

                 false), formName);

     }

     private static void appendAutoScrollAssignment(FacesContext context,

             ScriptContext scriptContext, String formName)

     {

         String formNameStr = formName == null ? "formName" : (new StringBuilder(

                 "'").append(formName).append("'").toString());

         String paramName = new StringBuilder().append("'")

                 .append(AUTO_SCROLL_PARAM).append("'").toString();

         String value = new StringBuilder().append(AUTO_SCROLL_FUNCTION)

                 .append("()").toString();

         scriptContext.prettyLine();

         scriptContext.append("if(typeof window." + AUTO_SCROLL_FUNCTION

                 + "!='undefined')");

         scriptContext.append("{");

         scriptContext.append(SET_HIDDEN_INPUT_FN_NAME_JSF2);

         scriptContext.append("(").append(formNameStr).append(",")

                 .append(paramName).append(",").append(value).append(");");

         scriptContext.append("}");

     }

     public static String getAutoScrollFunction(FacesContext facesContext)

     {

         ScriptContext script = new ScriptContext();

         script.prettyLineIncreaseIndent();

         script.append("function ");

         script.append(AUTO_SCROLL_FUNCTION);

         script.append("()");

         script.append("{");

         script.append("var x = 0; var y = 0;");

         script.append("if (self.pageXOffset || self.pageYOffset)");

         script.append("{");

         script.append("x = self.pageXOffset;");

         script.prettyLine();

         script.append("y = self.pageYOffset;");

         script.append("}");

         script.append(" else if ((document.documentElement && document.documentElement.scrollLeft)||"+

                 "(document.documentElement && document.documentElement.scrollTop))");

         script.append("{");

         script.append("x = document.documentElement.scrollLeft;");

         script.prettyLine();

         script.append("y = document.documentElement.scrollTop;");

         script.append("}");

         script.append(" else if (document.body) ");

         script.append("{");

         script.append("x = document.body.scrollLeft;");

         script.prettyLine();

         script.append("y = document.body.scrollTop;");

         script.append("}");

         script.append("return x + \",\" + y;");

         script.append("}");

         ExternalContext externalContext = facesContext.getExternalContext();

         String oldViewId = JavascriptUtils.getOldViewId(externalContext);

         if (oldViewId != null

                 && oldViewId.equals(facesContext.getViewRoot().getViewId()))

         {

             //ok, we stayed on the same page, so let's scroll it to the former place

             String scrolling = (String) externalContext

                     .getRequestParameterMap().get(AUTO_SCROLL_PARAM);

             if (scrolling != null && scrolling.length() > 0)

             {

                 double x = 0;

                 double y = 0;

                 int comma = scrolling.indexOf(',');

                 if (comma == -1)

                 {

                     log.warning("Illegal autoscroll request parameter: "

                             + scrolling);

                 }

                 else

                 {

                     try

                     {

                         //we convert to double against XSS vulnerability

                         x = Double.parseDouble(scrolling.substring(0, comma));

                     }

                     catch (NumberFormatException e)

                     {

                         log.warning("Error getting x offset for autoscroll feature. Bad param value: "

                                 + scrolling);

                         x = 0; //ignore false numbers

                     }

                     try

                     {

                         //we convert to int against XSS vulnerability

                         y = Integer.parseInt(scrolling.substring(comma + 1));

                     }

                     catch (NumberFormatException e)

                     {

                         log.warning("Error getting y offset for autoscroll feature. Bad param value: "

                                 + scrolling);

                         y = 0; //ignore false numbers

                     }

                 }

                 script.append("window.scrollTo(").append(String.valueOf(x)).append(",")

                         .append(String.valueOf(y)).append(");\n");

             }

         }

         return script.toString();

     }

     /**

      * Renders the hidden form input that is necessary for the autoscroll feature.

      */

     public static void renderAutoScrollHiddenInput(FacesContext facesContext,

             ResponseWriter writer) throws IOException

     {

         writer.startElement(HTML.INPUT_ELEM, null);

         writer.writeAttribute(HTML.TYPE_ATTR, "hidden", null);

         writer.writeAttribute(HTML.NAME_ATTR, AUTO_SCROLL_PARAM, null);

         writer.endElement(HTML.INPUT_ELEM);

     }

     /**

      * Renders the autoscroll javascript function.

      */

     public static void renderAutoScrollFunction(FacesContext facesContext,

             ResponseWriter writer) throws IOException

     {

         writer.startElement(HTML.SCRIPT_ELEM, null);

         writer.writeAttribute(HTML.SCRIPT_TYPE_ATTR,

                 HTML.SCRIPT_TYPE_TEXT_JAVASCRIPT, null);

         writer.writeText(getAutoScrollFunction(facesContext), null);

         writer.endElement(HTML.SCRIPT_ELEM);

     }

     public static void appendClearHiddenCommandFormParamsFunctionCall(

             StringBuilder buf, String formName)

     {

         appendClearHiddenCommandFormParamsFunctionCall(new ScriptContext(buf,

                 false), formName);

     }

     private static void appendClearHiddenCommandFormParamsFunctionCall(

             ScriptContext context, String formName)

     {

         String functionName = HtmlRendererUtils

                 .getClearHiddenCommandFormParamsFunctionName(formName);

         if (formName == null)

         {

             context.prettyLine();

             context.append("var clearFn = ");

             context.append(functionName);

             context.append(";");

             context.prettyLine();

             context.append("if(typeof window[clearFn] =='function')");

             context.append("{");

             context.append("window[clearFn](formName);");

             context.append("}");

         }

         else

         {

             context.prettyLine();

             context.append("if(typeof window.");

             context.append(functionName);

             context.append("=='function')");

             context.append("{");

             context.append(functionName).append("('").append(formName)

                     .append("');");

             context.append("}");

         }

     }

     /**

      * Prefixes the given String with "clear_" and removes special characters

      *

      * @param formName

      * @return String

      */

     public static String getClearHiddenCommandFormParamsFunctionName(

             String formName)

     {

         final char separatorChar = FacesContext.getCurrentInstance().getNamingContainerSeparatorChar();

         if (formName == null)

         {

             return "'" + HtmlRendererUtils.CLEAR_HIDDEN_FIELD_FN_NAME

                     + "_'+formName.replace(/-/g, '\\$" + separatorChar

                     + "').replace(/" + separatorChar + "/g,'_')";

         }

         return JavascriptUtils

                 .getValidJavascriptNameAsInRI(HtmlRendererUtils.CLEAR_HIDDEN_FIELD_FN_NAME + "_"

                         + formName.replace(separatorChar, '_'));

     }

     public static String getClearHiddenCommandFormParamsFunctionNameMyfacesLegacy(

             String formName)

     {

         return "clear_"

                 + JavascriptUtils.getValidJavascriptName(formName, false);

     }

     /**

      * Render the javascript function that is called on a click on a commandLink

      * to clear the hidden inputs. This is necessary because on a browser back,

      * each hidden input still has it's old value (browser cache!) and therefore

      * a new submit would cause the according action once more!

      *

      * @param writer

      * @param formName

      * @param dummyFormParams

      * @param formTarget

      * @throws IOException

      */

     public static void renderClearHiddenCommandFormParamsFunction(

             ResponseWriter writer, String formName, Set dummyFormParams,

             String formTarget) throws IOException

     {

         //render the clear hidden inputs javascript function

         String functionName = getClearHiddenCommandFormParamsFunctionName(formName);

         writer.startElement(HTML.SCRIPT_ELEM, null);

         writer.writeAttribute(HTML.TYPE_ATTR, "text/javascript", null);

         // Using writeComment instead of write with <!-- tag

         StringBuilder script = new StringBuilder();

         script.append("function ");

         script.append(functionName);

         script.append("() {");

         if (dummyFormParams != null)

         {

             script.append("\n  var f = document.forms['");

             script.append(formName);

             script.append("'];");

             int i = 0;

             for (Iterator it = dummyFormParams.iterator(); it.hasNext();)

             {

                 String elemVarName = "elem" + i;

                 script.append("\n  var ").append(elemVarName).append(" = ");

                 script.append("f.elements['").append((String) it.next())

                         .append("'];");

                 script.append("\n  if(typeof ").append(elemVarName)

                         .append(" !='undefined' && ");

                 script.append(elemVarName).append(".nodeName=='INPUT'){");

                 script.append("\n   if (").append(elemVarName)

                         .append(".value != '') {");

                 script.append("\n    " + elemVarName + ".value='';");

                 script.append("\n   }");

                 script.append("\n  }");

                 i++;

             }

         }

         // clear form target

         script.append("\n  f.target=");

         if (formTarget == null || formTarget.length() == 0)

         {

             //Normally one would think that setting target to null has the

             //desired effect, but once again IE is different...

             //Setting target to null causes IE to open a new window!

             script.append("'';");

         }

         else

         {

             script.append("'");

             script.append(formTarget);

             script.append("';");

         }

         script.append("\n}");

         //Just to be sure we call this clear method on each load.

         //Otherwise in the case, that someone submits a form by pressing Enter

         //within a text input, the hidden inputs won't be cleared!

         script.append("\n");

         script.append(functionName);

         script.append("();");

         writer.writeText(script.toString(), null);

         writer.endElement(HTML.SCRIPT_ELEM);

     }

     /**

      * This function correctly escapes the given JavaScript code

      * for the use in the jsf.util.chain() JavaScript function.

      * It also handles double-escaping correclty.

      *

      * @param javaScript

      * @return

      */

     public static String escapeJavaScriptForChain(String javaScript)

     {

         // first replace \' with \\'

         //String escaped = StringUtils.replace(javaScript, "\\'", "\\\\'");

         // then replace ' with \'

         // (this will replace every \' in the original to \\\')

         //escaped = StringUtils.replace(escaped, '\'', "\\'");

         //return escaped;

         StringBuilder out = null;

         for (int pos = 0; pos < javaScript.length(); pos++)

         {

             char c = javaScript.charAt(pos);

             if (c == '\\' || c == '\'')

             {

                 if (out == null)

                 {

                     out = new StringBuilder(javaScript.length() + 8);

                     if (pos > 0)

                     {

                         out.append(javaScript, 0, pos);

                     }

                 }

                 out.append('\\');

             }

             if (out != null)

             {

                 out.append(c);

             }

         }

         if (out == null)

         {

             return javaScript;

         }

         else

         {

             return out.toString();

         }

     }

 }