/*
    * 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.renderkit.html;
  
  import java.io.IOException;
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.EnumSet;
  import java.util.List;
  import java.util.Map;
  import java.util.RandomAccess;
  import java.util.Set;
  import javax.faces.component.UIComponent;
  import javax.faces.component.UIParameter;
  import javax.faces.component.behavior.AjaxBehavior;
  import javax.faces.component.behavior.ClientBehaviorContext;
  import javax.faces.component.behavior.ClientBehaviorHolder;
  import javax.faces.component.html.HtmlCommandScript;
  import javax.faces.component.search.SearchExpressionContext;
  import javax.faces.component.search.SearchExpressionHandler;
  import javax.faces.component.search.SearchExpressionHint;
  import javax.faces.context.FacesContext;
  import javax.faces.context.ResponseWriter;
  import javax.faces.event.ActionEvent;
  import org.apache.myfaces.buildtools.maven2.plugin.builder.annotation.JSFRenderer;
  import org.apache.myfaces.shared.renderkit.RendererUtils;
  import org.apache.myfaces.shared.renderkit.html.HTML;
  import org.apache.myfaces.shared.renderkit.html.HtmlRenderer;
  import org.apache.myfaces.shared.renderkit.html.HtmlRendererUtils;
  import org.apache.myfaces.shared.renderkit.html.util.FormInfo;
  import org.apache.myfaces.shared.renderkit.html.util.JavascriptUtils;
  import org.apache.myfaces.shared.renderkit.html.util.ResourceUtils;
  import org.apache.myfaces.shared.renderkit.html.util.SharedStringBuilder;
  import org.apache.myfaces.shared.util.StringUtils;
  
  @JSFRenderer(
      renderKitId="HTML_BASIC",
      family="javax.faces.Command",
      type="javax.faces.Script")
  public class HtmlCommandScriptRenderer extends HtmlRenderer
  {
      private static final Set<SearchExpressionHint> EXPRESSION_HINTS =
              EnumSet.of(SearchExpressionHint.RESOLVE_CLIENT_SIDE, SearchExpressionHint.RESOLVE_SINGLE_COMPONENT);
      
      private static final String AJAX_KEY_ONERROR = "onerror";
      private static final String AJAX_KEY_ONEVENT = "onevent";
      private static final String AJAX_KEY_EXECUTE = "execute";
      private static final String AJAX_KEY_RENDER = "render";
      private static final String AJAX_KEY_DELAY = "delay";
      private static final String AJAX_KEY_RESETVALUES = "resetValues";
  
      private static final String AJAX_VAL_THIS = "this";
      private static final String JS_AJAX_REQUEST = "jsf.ajax.request";
      
      private static final String AJAX_SB = "oam.renderkit.AJAX_SB";
      private static final String AJAX_PARAM_SB = "oam.renderkit.AJAX_PARAM_SB";
      
      @Override
      public void encodeBegin(FacesContext context, UIComponent component) throws IOException
      {
          super.encodeBegin(context, component);
  
          HtmlCommandScript commandScript = (HtmlCommandScript) component;
          ResponseWriter writer = context.getResponseWriter();
          
          ResourceUtils.renderDefaultJsfJsInlineIfNecessary(context, writer);
          
          writer.startElement(HTML.SPAN_ELEM, component);
          writer.writeAttribute(HTML.ID_ATTR, component.getClientId(context), null);
          writer.startElement(HTML.SCRIPT_ELEM, component);
          writer.writeAttribute(HTML.SCRIPT_TYPE_ATTR, HTML.SCRIPT_TYPE_TEXT_JAVASCRIPT, null);
          
          HtmlRendererUtils.ScriptContext script = new HtmlRendererUtils.ScriptContext();
          
          //Write content
          String cmdName = commandScript.getName();
          String name;
          if (cmdName != null && cmdName.length() > 0)
          {
              name = JavascriptUtils.getValidJavascriptName(cmdName, true);
          }
          else
         {
             name = JavascriptUtils.getValidJavascriptName(component.getClientId(context), true);
         }
         
         script.prettyLine();
         script.increaseIndent();
         script.append("var "+name+" = function(o){var o=(typeof o==='object')&&o?o:{};");
         script.prettyLine();
         
         // TODO ajaxBehavior not required actually....
         AjaxBehavior ajaxBehavior = new AjaxBehavior();
         Boolean resetValues = commandScript.getResetValues();
         if (resetValues != null)
         {
             ajaxBehavior.setResetValues(resetValues);
         }
         ajaxBehavior.setOnerror(commandScript.getOnerror());
         ajaxBehavior.setOnevent(commandScript.getOnevent());
         
         Collection<ClientBehaviorContext.Parameter> eventParameters = null;    
         //eventParameters.add(new ClientBehaviorContext.Parameter("params", "o"));
         ClientBehaviorContext ccc = ClientBehaviorContext.createClientBehaviorContext(
                                     context, component, "action",
                                     commandScript.getClientId(context), eventParameters);
         
         script.append(makeAjax(context, ccc, ajaxBehavior, commandScript).toString());
         script.decreaseIndent();
         script.append("}");
         
         
         if (commandScript.isAutorun())
         {
             script.append(";");
             script.append("myfaces._impl.core._Runtime.addOnLoad(window,");
             script.append(name);
             script.append(");");
         }
         
         writer.writeText(script.toString(), null);
     }
     
     @Override
     public void encodeEnd(FacesContext context, UIComponent component) throws IOException
     {
         super.encodeEnd(context, component); //
         ResponseWriter writer = context.getResponseWriter();
         writer.endElement(HTML.SCRIPT_ELEM);
         writer.endElement(HTML.SPAN_ELEM);
     }
 
     @Override
     public void decode(FacesContext facesContext, UIComponent component)
     {
         super.decode(facesContext, component); 
         
         HtmlCommandScript commandScript = (HtmlCommandScript) component;
         
         if (HtmlRendererUtils.isDisabled(component) || !commandScript.isRendered())
         {
             return;
         }
         
         Map<String, String> paramMap = facesContext.getExternalContext().getRequestParameterMap();
         String behaviorEventName = paramMap.get(ClientBehaviorContext.BEHAVIOR_EVENT_PARAM_NAME);
         if (behaviorEventName != null)
         {
             String sourceId = paramMap.get(ClientBehaviorContext.BEHAVIOR_SOURCE_PARAM_NAME);
             String componentClientId = component.getClientId(facesContext);
             String clientId = sourceId;
             if (sourceId.startsWith(componentClientId) && sourceId.length() > componentClientId.length())
             {
                 String item = sourceId.substring(componentClientId.length()+1);
                 // If is item it should be an integer number, otherwise it can be related to a child 
                 // component, because that could conflict with the clientId naming convention.
                 if (StringUtils.isInteger(item))
                 {
                     clientId = componentClientId;
                 }
             }
             if (component.getClientId(facesContext).equals(clientId))
             {
                 boolean disabled = HtmlRendererUtils.isDisabled(component);
                 FormInfo formInfo = RendererUtils.findNestingForm(component, facesContext);
                 boolean activateActionEvent = false;
                 if (formInfo != null && !disabled)
                 {
                     String reqValue = (String) facesContext.getExternalContext().getRequestParameterMap().get(
                             HtmlRendererUtils.getHiddenCommandLinkFieldName(formInfo, facesContext));
                     activateActionEvent = reqValue != null && reqValue.equals(clientId)
                         || HtmlRendererUtils.isPartialOrBehaviorSubmit(facesContext, clientId);
                     if (activateActionEvent)
                     {
                         RendererUtils.initPartialValidationAndModelUpdate(component, facesContext);
                     }
                 }
                 if (activateActionEvent)
                 {
                     component.queueEvent(new ActionEvent(component));
                 }
             }
         }
         if (component instanceof ClientBehaviorHolder && !HtmlRendererUtils.isDisabled(component))
         {
             HtmlRendererUtils.decodeClientBehaviors(facesContext, component);
         }
     }
 
     /**
      * builds the generic ajax call depending upon
      * the ajax behavior parameters
      *
      * @param context  the Client behavior context
      * @param behavior the behavior
      * @param commandScript the component
      * @return a fully working javascript with calls into jsf.js
      */
     private StringBuilder makeAjax(FacesContext facesContext, ClientBehaviorContext context, AjaxBehavior behavior,
             HtmlCommandScript commandScript)
     {
         StringBuilder retVal = SharedStringBuilder.get(context.getFacesContext(), AJAX_SB, 60);
         StringBuilder paramBuffer = SharedStringBuilder.get(context.getFacesContext(), AJAX_PARAM_SB, 20);
     
         SearchExpressionContext searchExpressionContext = SearchExpressionContext.createSearchExpressionContext(
                             context.getFacesContext(), context.getComponent(), EXPRESSION_HINTS, null);
         
         String executes = resolveExpressionsAsParameter(paramBuffer, AJAX_KEY_EXECUTE, commandScript.getExecute(),
                 searchExpressionContext);
         String render = resolveExpressionsAsParameter(paramBuffer, AJAX_KEY_RENDER, commandScript.getRender(),
                 searchExpressionContext);
 
         String onError = behavior.getOnerror();
         if (onError != null && !onError.trim().isEmpty())
         {
             //onError = AJAX_KEY_ONERROR + COLON + onError;
             paramBuffer.setLength(0);
             paramBuffer.append(AJAX_KEY_ONERROR);
             paramBuffer.append(':');
             paramBuffer.append(onError);
             onError = paramBuffer.toString();
         }
         else
         {
             onError = null;
         }
         String onEvent = behavior.getOnevent();
         if (onEvent != null && !onEvent.trim().isEmpty())
         {
             paramBuffer.setLength(0);
             paramBuffer.append(AJAX_KEY_ONEVENT);
             paramBuffer.append(':');
             paramBuffer.append(onEvent);
             onEvent = paramBuffer.toString();
         }
         else
         {
             onEvent = null;
         }
 
         String delay = behavior.getDelay();
         if (delay != null && !delay.trim().isEmpty())
         {
             paramBuffer.setLength(0);
             paramBuffer.append(AJAX_KEY_DELAY);
             paramBuffer.append(':');
             if ("none".equals(delay))
             {
                 paramBuffer.append('\'');
                 paramBuffer.append(delay);
                 paramBuffer.append('\'');
             }
             else
             {
                 paramBuffer.append(delay);
             }
             delay = paramBuffer.toString();
         }
         else
         {
             delay = null;
         }
 
         String resetValues = Boolean.toString(behavior.isResetValues());
         if (resetValues.equals("true"))
         {
             paramBuffer.setLength(0);
             paramBuffer.append(AJAX_KEY_RESETVALUES);
             paramBuffer.append(':');
             paramBuffer.append(resetValues);
             resetValues = paramBuffer.toString();
         }
         else
         {
             resetValues = null;
         }
 
         String sourceId = null;
         if (context.getSourceId() == null)
         {
             sourceId = AJAX_VAL_THIS;
         }
         else
         {
             paramBuffer.setLength(0);
             paramBuffer.append('\'');
             paramBuffer.append(context.getSourceId());
             paramBuffer.append('\'');
             sourceId = paramBuffer.toString();
 
             if (!context.getSourceId().trim().equals(
                 context.getComponent().getClientId(context.getFacesContext())))
             {
                 // Check if sourceId is not a clientId and there is no execute set
                 UIComponent ref = context.getComponent();
                 ref = (ref.getParent() == null) ? ref : ref.getParent();
                 UIComponent instance = null;
                 try
                 {
                     instance = ref.findComponent(context.getSourceId());
                 }
                 catch (IllegalArgumentException e)
                 {
                     // No Op
                 }
                 if (instance == null && executes == null)
                 {
                     // set the clientId of the component so the behavior can be decoded later,
                     // otherwise the behavior will fail
                     executes = resolveExpressionsAsParameter(paramBuffer, AJAX_KEY_EXECUTE,
                             context.getComponent().getClientId(context.getFacesContext()), searchExpressionContext);
                 }
             }
         }
 
         String event = context.getEventName();
 
         retVal.append(JS_AJAX_REQUEST);
         retVal.append('(');
         retVal.append(sourceId);
         retVal.append(",window.event,myfaces._impl._util._Lang.mixMaps(");
         
         Collection<ClientBehaviorContext.Parameter> params = context.getParameters();
         int paramSize = (params != null) ? params.size() : 0;
 
         List<String> parameterList = new ArrayList<>(paramSize + 2);
         if (executes != null)
         {
             parameterList.add(executes);
         }
         if (render != null)
         {
             parameterList.add(render);
         }
         if (onError != null)
         {
             parameterList.add(onError);
         }
         if (onEvent != null)
         {
             parameterList.add(onEvent);
         }
         if (delay != null)
         {
             parameterList.add(delay);
         }
         if (resetValues != null)
         {
             parameterList.add(resetValues);
         }
         if (paramSize > 0)
         {
             /**
              * see ClientBehaviorContext.html of the spec
              * the param list has to be added in the post back
              */
             // params are in 99% RamdonAccess instace created in
             // HtmlRendererUtils.getClientBehaviorContextParameters(Map<String, String>)
             if (params instanceof RandomAccess)
             {
                 List<ClientBehaviorContext.Parameter> list = (List<ClientBehaviorContext.Parameter>) params;
                 for (int i = 0, size = list.size(); i < size; i++)
                 {
                     ClientBehaviorContext.Parameter param = list.get(i);
                     append(paramBuffer, parameterList, param.getName(), param.getValue());
                 }
             }
             else
             {
                 for (ClientBehaviorContext.Parameter param : params)
                 {
                     append(paramBuffer, parameterList, param.getName(), param.getValue());
                 }
             }
         }
         
         List<UIParameter> uiParams = HtmlRendererUtils.getValidUIParameterChildren(
                 facesContext, commandScript.getChildren(), false, false);
         if (uiParams != null && uiParams.size() > 0)
         {
             for (int i = 0, size = uiParams.size(); i < size; i++)
             {
                 UIParameter param = uiParams.get(i);
                 append(paramBuffer, parameterList, param.getName(), param.getValue());
             }
         }
             
         paramBuffer.setLength(0);
         paramBuffer.append('\'');
         paramBuffer.append(ClientBehaviorContext.BEHAVIOR_EVENT_PARAM_NAME);
         paramBuffer.append("\':\'");
         paramBuffer.append(event);
         paramBuffer.append('\'');
         parameterList.add(paramBuffer.toString());
 
         /**
          * I assume here for now that the options are the same which also
          * can be sent via the options attribute to javax.faces.ajax
          * this still needs further clarifications but I assume so for now
          */
         retVal.append(buildOptions(paramBuffer, parameterList));
 
         //mixMaps
         retVal.append(",o,false))");
 
         return retVal;
     }
 
     private void append(StringBuilder paramBuffer, List<String> parameterList, String paramName, Object paramValue)
     {
         //TODO we may need a proper type handling in this part
         //lets leave it for now as it is
         //quotes etc.. should be transferred directly
         //and the rest is up to the toString properly implemented
         //ANS: Both name and value should be quoted
         paramBuffer.setLength(0);
         paramBuffer.append('\'');
         paramBuffer.append(paramName);
         paramBuffer.append("\':\'");
         if (paramValue != null)
         {
             paramBuffer.append(paramValue.toString());
         }
         paramBuffer.append('\'');
         parameterList.add(paramBuffer.toString());
     }
 
     private StringBuilder buildOptions(StringBuilder retVal, List<String> options)
     {
         retVal.setLength(0);
 
         retVal.append("{");
 
         boolean first = true;
 
         for (int i = 0, size = options.size(); i < size; i++)
         {
             String option = options.get(i);
             if (option != null && !option.trim().isEmpty())
             {
                 if (!first)
                 {
                     retVal.append(',');
                 }
                 else
                 {
                     first = false;
                 }
                 retVal.append(option);
             }
         }
         retVal.append("}");
         return retVal;
     }
 
     private String resolveExpressionsAsParameter(StringBuilder retVal, String target, String expressions,
             SearchExpressionContext searchExpressionContext)
     {
         if (expressions != null && !expressions.trim().isEmpty())
         {
             retVal.setLength(0);
             retVal.append(target);
             retVal.append(':');
             retVal.append('\'');
 
             SearchExpressionHandler handler =
                     searchExpressionContext.getFacesContext().getApplication().getSearchExpressionHandler();
             List<String> clientIds =
                     handler.resolveClientIds(searchExpressionContext, expressions);
             
             if (clientIds != null && !clientIds.isEmpty())
             {
                 for (int i = 0; i < clientIds.size(); i++)
                 {
                     if (i > 0)
                     {
                         retVal.append(' ');
                     }
                     retVal.append(clientIds.get(i));
                 }
             }
             
             retVal.append('\'');
             return retVal.toString();
         }
 
         return null;
     }
 }