/*
* Copyright 2004 The Apache Software Foundation
*
* Licensed 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 javax.servlet.jsp.tagext;

/**
 * Tag information for a tag in a Tag Library;
 * This class is instantiated from the Tag Library Descriptor file (TLD)
 * and is available only at translation time.
 *
 * 
*/

public class TagInfo {

    /**
     * Static constant for getBodyContent() when it is JSP.
     */

    public static final String BODY_CONTENT_JSP = "JSP";

    /**
     * Static constant for getBodyContent() when it is Tag dependent.
     */

    public static final String BODY_CONTENT_TAG_DEPENDENT = "TAGDEPENDENT";


    /**
     * Static constant for getBodyContent() when it is empty.
     */

    public static final String BODY_CONTENT_EMPTY = "EMPTY";
    
    /**
     * Static constant for getBodyContent() when it is scriptless.
     * 
     * @since 2.0
     */ 
    public static final String BODY_CONTENT_SCRIPTLESS = "SCRIPTLESS";

    /**
     * Constructor for TagInfo from data in the JSP 1.1 format for TLD.
     * This class is to be instantiated only from the TagLibrary code
     * under request from some JSP code that is parsing a
     * TLD (Tag Library Descriptor).
     *
     * Note that, since TagLibibraryInfo reflects both TLD information
     * and taglib directive information, a TagInfo instance is
     * dependent on a taglib directive.  This is probably a
     * design error, which may be fixed in the future.
     *
     * @param tagName The name of this tag
     * @param tagClassName The name of the tag handler class
     * @param bodycontent Information on the body content of these tags
     * @param infoString The (optional) string information for this tag
     * @param taglib The instance of the tag library that contains us.
     * @param tagExtraInfo The instance providing extra Tag info.  May be null
     * @param attributeInfo An array of AttributeInfo data from descriptor.
     * May be null;
     *
     */
    public TagInfo(String tagName,
	    String tagClassName,
	    String bodycontent,
	    String infoString,
	    TagLibraryInfo taglib,
	    TagExtraInfo tagExtraInfo,
	    TagAttributeInfo[] attributeInfo) {
	this.tagName       = tagName;
	this.tagClassName  = tagClassName;
	this.bodyContent   = bodycontent;
	this.infoString    = infoString;
	this.tagLibrary    = taglib;
	this.tagExtraInfo  = tagExtraInfo;
	this.attributeInfo = attributeInfo;

	if (tagExtraInfo != null)
            tagExtraInfo.setTagInfo(this);
    }
			 
    /**
     * Constructor for TagInfo from data in the JSP 1.2 format for TLD.
     * This class is to be instantiated only from the TagLibrary code
     * under request from some JSP code that is parsing a
     * TLD (Tag Library Descriptor).
     *
     * Note that, since TagLibibraryInfo reflects both TLD information
     * and taglib directive information, a TagInfo instance is
     * dependent on a taglib directive.  This is probably a
     * design error, which may be fixed in the future.
     *
     * @param tagName The name of this tag
     * @param tagClassName The name of the tag handler class
     * @param bodycontent Information on the body content of these tags
     * @param infoString The (optional) string information for this tag
     * @param taglib The instance of the tag library that contains us.
     * @param tagExtraInfo The instance providing extra Tag info.  May be null
     * @param attributeInfo An array of AttributeInfo data from descriptor.
     * May be null;
     * @param displayName A short name to be displayed by tools
     * @param smallIcon Path to a small icon to be displayed by tools
     * @param largeIcon Path to a large icon to be displayed by tools
     * @param tvi An array of a TagVariableInfo (or null)
     */
    public TagInfo(String tagName,
	    String tagClassName,
	    String bodycontent,
	    String infoString,
	    TagLibraryInfo taglib,
	    TagExtraInfo tagExtraInfo,
	    TagAttributeInfo[] attributeInfo,
	    String displayName,
	    String smallIcon,
	    String largeIcon,
	    TagVariableInfo[] tvi) {
	this.tagName       = tagName;
	this.tagClassName  = tagClassName;
	this.bodyContent   = bodycontent;
	this.infoString    = infoString;
	this.tagLibrary    = taglib;
	this.tagExtraInfo  = tagExtraInfo;
	this.attributeInfo = attributeInfo;
	this.displayName = displayName;
	this.smallIcon = smallIcon;
	this.largeIcon = largeIcon;
	this.tagVariableInfo = tvi;

	if (tagExtraInfo != null)
            tagExtraInfo.setTagInfo(this);
    }
			 
    /**
     * Constructor for TagInfo from data in the JSP 2.0 format for TLD.
     * This class is to be instantiated only from the TagLibrary code
     * under request from some JSP code that is parsing a
     * TLD (Tag Library Descriptor).
     *
     * Note that, since TagLibibraryInfo reflects both TLD information
     * and taglib directive information, a TagInfo instance is
     * dependent on a taglib directive.  This is probably a
     * design error, which may be fixed in the future.
     *
     * @param tagName The name of this tag
     * @param tagClassName The name of the tag handler class
     * @param bodycontent Information on the body content of these tags
     * @param infoString The (optional) string information for this tag
     * @param taglib The instance of the tag library that contains us.
     * @param tagExtraInfo The instance providing extra Tag info.  May be null
     * @param attributeInfo An array of AttributeInfo data from descriptor.
     * May be null;
     * @param displayName A short name to be displayed by tools
     * @param smallIcon Path to a small icon to be displayed by tools
     * @param largeIcon Path to a large icon to be displayed by tools
     * @param tvi An array of a TagVariableInfo (or null)
     * @param dynamicAttributes True if supports dynamic attributes
     *
     * @since 2.0
     */
    public TagInfo(String tagName,
            String tagClassName,
            String bodycontent,
            String infoString,
            TagLibraryInfo taglib,
            TagExtraInfo tagExtraInfo,
            TagAttributeInfo[] attributeInfo,
            String displayName,
            String smallIcon,
            String largeIcon,
            TagVariableInfo[] tvi,
            boolean dynamicAttributes) {
        this.tagName       = tagName;
        this.tagClassName  = tagClassName;
        this.bodyContent   = bodycontent;
        this.infoString    = infoString;
        this.tagLibrary    = taglib;
        this.tagExtraInfo  = tagExtraInfo;
        this.attributeInfo = attributeInfo;
        this.displayName = displayName;
        this.smallIcon = smallIcon;
        this.largeIcon = largeIcon;
        this.tagVariableInfo = tvi;
        this.dynamicAttributes = dynamicAttributes;

        if (tagExtraInfo != null)
            tagExtraInfo.setTagInfo(this);
    }

    /**
     * The name of the Tag.
     *
     * @return The (short) name of the tag.
     */

    public String getTagName() {
	return tagName;
    }

    /**
     * Attribute information (in the TLD) on this tag.
     * The return is an array describing the attributes of this tag, as
     * indicated in the TLD.
     *
     * @return The array of TagAttributeInfo for this tag, or a
     *         zero-length array if the tag has no attributes.
     */

   public TagAttributeInfo[] getAttributes() {
       return attributeInfo;
   }

    /**
     * Information on the scripting objects created by this tag at runtime.
     * This is a convenience method on the associated TagExtraInfo class.
     *
     * @param data TagData describing this action.
     * @return if a TagExtraInfo object is associated with this TagInfo, the
     *     result of getTagExtraInfo().getVariableInfo( data ), otherwise
     *     null.
     */
   public VariableInfo[] getVariableInfo(TagData data) {
       VariableInfo[] result = null;
       TagExtraInfo tei = getTagExtraInfo();
       if (tei != null) {
	   result = tei.getVariableInfo( data );
       }
       return result;
   }

    /**
     * Translation-time validation of the attributes. 
     * This is a convenience method on the associated TagExtraInfo class.
     *
     * @param data The translation-time TagData instance.
     * @return Whether the data is valid.
     */
    public boolean isValid(TagData data) {
        TagExtraInfo tei = getTagExtraInfo();
        if (tei == null) {
	    return true;
        }
        return tei.isValid(data);
    }

    /**
     * Translation-time validation of the attributes.
     * This is a convenience method on the associated TagExtraInfo class.
     *
     * @param data The translation-time TagData instance.
     * @return A null object, or zero length array if no errors, an
     *     array of ValidationMessages otherwise.
     * @since 2.0
     */
    public ValidationMessage[] validate( TagData data ) {
	TagExtraInfo tei = getTagExtraInfo();
	if( tei == null ) {
	    return null;
	}
	return tei.validate( data );
    }

    /**
     * Set the instance for extra tag information.
     * 
     * @param tei the TagExtraInfo instance
     */
    public void setTagExtraInfo(TagExtraInfo tei) {
	tagExtraInfo = tei;
    }


    /**
     * The instance (if any) for extra tag information.
     * 
     * @return The TagExtraInfo instance, if any.
     */
    public TagExtraInfo getTagExtraInfo() {
	return tagExtraInfo;
    }


    /**
     * Name of the class that provides the handler for this tag.
     *
     * @return The name of the tag handler class.
     */
    
    public String getTagClassName() {
	return tagClassName;
    }


    /**
     * The bodycontent information for this tag.
     * If the bodycontent is not defined for this
     * tag, the default of JSP will be returned.
     *
     * @return the body content string.
     */

    public String getBodyContent() {
	return bodyContent;
    }


    /**
     * The information string for the tag.
     *
     * @return the info string, or null if 
     *         not defined
     */

    public String getInfoString() {
	return infoString;
    }


    /**
     * Set the TagLibraryInfo property.
     *
     * Note that a TagLibraryInfo element is dependent
     * not just on the TLD information but also on the
     * specific taglib instance used.  This means that
     * a fair amount of work needs to be done to construct
     * and initialize TagLib objects.
     *
     * If used carefully, this setter can be used to avoid having to
     * create new TagInfo elements for each taglib directive.
     *
     * @param tl the TagLibraryInfo to assign
     */

    public void setTagLibrary(TagLibraryInfo tl) {
	tagLibrary = tl;
    }

    /**
     * The instance of TabLibraryInfo we belong to.
     *
     * @return the tag library instance we belong to
     */

    public TagLibraryInfo getTagLibrary() {
	return tagLibrary;
    }


    // ============== JSP 2.0 TLD Information ========


    /**
     * Get the displayName.
     *
     * @return A short name to be displayed by tools,
     *         or null if not defined
     */

    public String getDisplayName() {
	return displayName;
    }

    /**
     * Get the path to the small icon.
     *
     * @return Path to a small icon to be displayed by tools,
     *         or null if not defined
     */

    public String getSmallIcon() {
	return smallIcon;
    }

    /**
     * Get the path to the large icon.
     *
     * @return Path to a large icon to be displayed by tools,
     *         or null if not defined
     */

    public String getLargeIcon() {
	return largeIcon;
    }

    /**
     * Get TagVariableInfo objects associated with this TagInfo.
     *
     * @return Array of TagVariableInfo objects corresponding to
     *         variables declared by this tag, or a zero length
     *         array if no variables have been declared
     */

    public TagVariableInfo[] getTagVariableInfos() {
	return tagVariableInfo;
    }


    // ============== JSP 2.0 TLD Information ========

    /**
     * Get dynamicAttributes associated with this TagInfo.
     *
     * @return True if tag handler supports dynamic attributes
     * @since 2.0
     */
    public boolean hasDynamicAttributes() {
        return dynamicAttributes;
    }

    /*
     * private fields for 1.1 info
     */
    private String             tagName; // the name of the tag
    private String             tagClassName;
    private String             bodyContent;
    private String             infoString;
    private TagLibraryInfo     tagLibrary;
    private TagExtraInfo       tagExtraInfo; // instance of TagExtraInfo
    private TagAttributeInfo[] attributeInfo;

    /*
     * private fields for 1.2 info
     */
    private String             displayName;
    private String             smallIcon;
    private String             largeIcon;
    private TagVariableInfo[]  tagVariableInfo;

    /*
     * Additional private fields for 2.0 info
     */
    private boolean dynamicAttributes;
}