/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */


/**
 * MODULE NOTES:
 * @update  gess 4/1/98
 * 
 * This class is defines the basic interface between the
 * parser and the content sink. The parser will iterate
 * over the collection of tokens that it sees from the
 * tokenizer, coverting each related "group" into one of
 * these. This object gets passed to the sink, and is
 * then immediately reused.
 *
 * If you want to hang onto one of these, you should
 * make your own copy.
 *
 */

#ifndef NS_IPARSERNODE__
#define NS_IPARSERNODE__

#include "nsISupports.h"
#include "prtypes.h"
#include "nsStringGlue.h"
#include "nsDebug.h"

//#define HEAP_ALLOCATED_NODES 
//#define DEBUG_TRACK_NODES

class nsIAtom;
class CToken;

// 6e59f160-2717-11d2-9246-00805f8a7ab6
#define NS_IPARSER_NODE_IID      \
  {0x6e59f160, 0x2717,  0x11d1,  \
  {0x92, 0x46, 0x00,    0x80, 0x5f, 0x8a, 0x7a, 0xb6}}

/**
 *  Parser nodes are the unit of exchange between the 
 *  parser and the content sink. Nodes offer access to
 *  the current token, its attributes, and its skipped-
 *  content if applicable.
 *  
 *  @update  gess 3/25/98
 */
class nsIParserNode { // XXX Should be nsAParserNode
            
  public:


    /**
     * Retrieve the name of the node
     * @update	gess5/11/98
     * @return  string containing node name
     */
    virtual const nsAString& GetTagName() const = 0;  //to get name of tag

    /**
     * Retrieve the text from the given node
     * @update	gess5/11/98
     * @return  string containing node text
     */
    virtual const nsAString& GetText() const = 0;  //get plain text if available

    /**
     * Retrieve the type of the parser node.
     * @update	gess5/11/98
     * @return  node type.
     */
    virtual PRInt32 GetNodeType()  const =0;

    /**
     * Retrieve token type of parser node
     * @update	gess5/11/98
     * @return  token type
     */
    virtual PRInt32 GetTokenType()  const =0;

    /**
     * Retrieve the number of attributes in this node.
     * @update	gess5/11/98
     * @return  count of attributes (may be 0)
     */
    virtual PRInt32 GetAttributeCount(bool askToken=false) const =0;

    /**
     * Retrieve the key (of key/value pair) at given index
     * @update	gess5/11/98
     * @param   anIndex is the index of the key you want
     * @return  string containing key.
     */
    virtual const nsAString& GetKeyAt(PRUint32 anIndex) const = 0;

    /**
     * Retrieve the value (of key/value pair) at given index
     * @update	gess5/11/98
     * @param   anIndex is the index of the value you want
     * @return  string containing value.
     */
    virtual const nsAString& GetValueAt(PRUint32 anIndex) const = 0;

    /**
     * NOTE: When the node is an entity, this will translate the entity
     *       to it's unicode value, and store it in aString.
     * @update	gess5/11/98
     * @param   aString will contain the resulting unicode string value
     * @return  int (unicode char or unicode index from table)
     */
    virtual PRInt32 TranslateToUnicodeStr(nsString& aString) const = 0;


    virtual void AddAttribute(CToken* aToken)=0;

    /**
     * This getter retrieves the line number from the input source where
     * the token occurred. Lines are interpreted as occurring between \n characters.
     * @update	gess7/24/98
     * @return  int containing the line number the token was found on
     */
    virtual PRInt32 GetSourceLineNumber(void) const =0;

    /**
     * This pair of methods allows us to set a generic bit (for arbitrary use)
     * on each node stored in the context.
     * @update	gess 11May2000
     */
    virtual bool    GetGenericState(void) const =0;
    virtual void    SetGenericState(bool aState) =0;

    /** Retrieve a string containing the tag and its attributes in "source" form
     * @update	rickg 06June2000
     * @return  void
     */
    virtual void GetSource(nsString& aString) const = 0;

    /** Release all the objects you're holding
     * @update	harishd 08/02/00
     * @return  void
     */
    virtual nsresult ReleaseAll()=0;
};

#endif
