HtmlTextRenderer

/*
 * 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.ext;

import java.io.IOException;
import java.util.Map;

import javax.faces.component.UIComponent;
import javax.faces.component.UIInput;
import javax.faces.context.FacesContext;
import javax.faces.context.ResponseWriter;

import org.apache.myfaces.component.UserRoleUtils;
import org.apache.myfaces.component.html.ext.HtmlInputText;
import org.apache.myfaces.shared_tomahawk.renderkit.JSFAttr;
import org.apache.myfaces.shared_tomahawk.renderkit.RendererUtils;
import org.apache.myfaces.shared_tomahawk.renderkit.html.HTML;
import org.apache.myfaces.shared_tomahawk.renderkit.html.HtmlRendererUtils;
import org.apache.myfaces.shared_tomahawk.renderkit.html.HtmlTextRendererBase;
import org.apache.myfaces.shared_tomahawk.renderkit.html.util.JavascriptUtils;


/**
 * @JSFRenderer
 *   renderKitId = "HTML_BASIC"
 *   family = "javax.faces.Input"
 *   type = "org.apache.myfaces.Text"
 *
 * @JSFRenderer
 *   renderKitId = "HTML_BASIC"
 *   family = "javax.faces.Output"
 *   type = "org.apache.myfaces.Text"
 *
 * @author Manfred Geiler (latest modification by $Author: lu4242 $)
 * @version $Revision: 659874 $ $Date: 2008-05-24 15:59:15 -0500 (Sat, 24 May 2008) $
 */
public class HtmlTextRenderer
        extends HtmlTextRendererBase
{
    private static final String ONCHANGE_PREFIX = "onChange_";
    private static final String HIDDEN_SUFFIX   = "_hidden";

    //private static final Log log = LogFactory.getLog(HtmlTextRenderer.class);
    protected boolean isDisabled(FacesContext facesContext, UIComponent uiComponent)
    {
        if (!UserRoleUtils.isEnabledOnUserRole(uiComponent))
        {
            return true;
        }
        else
        {
            return super.isDisabled(facesContext, uiComponent);
        }
    }
    /**
     *
     */
    protected boolean isDisabledOnClientSide(FacesContext facesContext, UIComponent component)
    {
        if (component instanceof HtmlInputText)
        {
            return ((HtmlInputText)component).isDisabledOnClientSide();
        }

        return false;
    }

    public void encodeEnd(FacesContext facesContext, UIComponent component)
        throws IOException
    {
        if (HtmlRendererUtils.isDisplayValueOnly(component))
        {
            renderInputValueOnly(facesContext, component);
        }
        else
        {
            renderNormal(facesContext, component);
        }
    }

    protected void renderInput(FacesContext facesContext, UIComponent component) throws IOException
    {
        if (!isDisabledOnClientSide(facesContext, component) || isDisabled(facesContext, component))
        {
            super.renderInput(facesContext, component);
            return;
        }

        //render the input component as if it was disabled
        ResponseWriter writer = facesContext.getResponseWriter();

        String clientId = component.getClientId(facesContext);
        String value = RendererUtils.getStringValue(facesContext, component);

        writer.startElement(HTML.INPUT_ELEM, component);
        writer.writeAttribute(HTML.ID_ATTR, clientId, null);
        writer.writeAttribute(HTML.NAME_ATTR, clientId, null);
        writer.writeAttribute(HTML.TYPE_ATTR, HTML.INPUT_TYPE_TEXT, null);
        if (value != null)
        {
            writer.writeAttribute(HTML.VALUE_ATTR, value, JSFAttr.VALUE_ATTR);
        }

        HtmlRendererUtils.renderHTMLAttributes(writer, component, HTML.INPUT_PASSTHROUGH_ATTRIBUTES_WITHOUT_DISABLED);
        //render as disabled on the client side
        writer.writeAttribute(HTML.DISABLED_ATTR, Boolean.TRUE, null);
        //render the JS function that will change the hidden input field's value when his changes
        writer.writeAttribute(HTML.ONCHANGE_ATTR, getOnChangeFunctionName(clientId)+"();", null);

        writer.endElement(HTML.INPUT_ELEM);

        //render the hidden input field that will hold this component's value
        renderHiddenInput(facesContext, (UIInput)component);
    }
    /**
     *
     */
    protected void renderHiddenInput(FacesContext facesContext, UIComponent component) throws IOException
    {
        ResponseWriter writer = facesContext.getResponseWriter();

        String disabledInputClientId = component.getClientId(facesContext);

        HtmlRendererUtils.writePrettyLineSeparator(facesContext);

        writer.startElement(HTML.SCRIPT_ELEM, null);
        writer.writeAttribute(HTML.SCRIPT_TYPE_ATTR, HTML.SCRIPT_TYPE_TEXT_JAVASCRIPT, null);
        writer.writeText(createOnChangeListenerJS(disabledInputClientId), null);
        writer.endElement(HTML.SCRIPT_ELEM);

        HtmlRendererUtils.writePrettyLineSeparator(facesContext);

        writer.startElement(HTML.INPUT_ELEM, null);
        writer.writeAttribute(HTML.ID_ATTR, disabledInputClientId + HIDDEN_SUFFIX, null);
        writer.writeAttribute(HTML.NAME_ATTR, disabledInputClientId + HIDDEN_SUFFIX, null);
        writer.writeAttribute(HTML.VALUE_ATTR, RendererUtils.getStringValue(facesContext, component), null);
        writer.writeAttribute(HTML.TYPE_ATTR, HTML.INPUT_TYPE_HIDDEN, null);
        writer.endElement(HTML.INPUT_ELEM);

        HtmlRendererUtils.writePrettyLineSeparator(facesContext);
    }

    protected void renderInputValueOnly(FacesContext facesContext, UIComponent component)
        throws IOException
    {
            HtmlRendererUtils.renderDisplayValueOnly(facesContext,
                                                     (UIInput) component);
    }

    protected void renderNormal(FacesContext facesContext, UIComponent component)
        throws IOException
    {
            super.encodeEnd(facesContext, component);
    }

    /**
     *
     */
    protected String getOnChangeFunctionName(String inputDisabledClientId)
    {
        StringBuffer buf = new StringBuffer();
        buf.append(ONCHANGE_PREFIX);
        buf.append(JavascriptUtils.getValidJavascriptName(inputDisabledClientId, true));

        return buf.toString();
    }
    /**
     *
     */
    protected String createOnChangeListenerJS(String inputDisabledClientId)
    {
        StringBuffer script = new StringBuffer();
        script.append("function ");
        script.append(getOnChangeFunctionName(inputDisabledClientId));
        script.append("() {\n");
        script.append("var hiddenInput = document.getElementById(\"").append(inputDisabledClientId + HIDDEN_SUFFIX).append("\");\n");
        script.append("var disabledInput = document.getElementById(\"").append(inputDisabledClientId).append("\");\n");
        script.append("hiddenInput.value=disabledInput.value;\n");
        script.append("}\n");

        return script.toString();
    }

    public void decode(FacesContext facesContext, UIComponent component)
    {
        if (isDisabledOnClientSide(facesContext, component) && !isDisabled(facesContext, component))
        {
            //in this case we don't need to check the request parameters validity,
            //the submitted value comes from the hidden input field
            Map paramValuesMap = facesContext.getExternalContext().getRequestParameterMap();
            Object reqValue = paramValuesMap.get(component.getClientId(facesContext) + HIDDEN_SUFFIX);

            ((UIInput)component).setSubmittedValue(reqValue);
            return;
        }

        super.decode(facesContext, component);
    }
}