gecko-dev/parser/htmlparser/public/nsIDTD.h

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/*
 * The contents of this file are subject to the Netscape Public
 * License Version 1.1 (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.mozilla.org/NPL/
 *
 * Software distributed under the License is distributed on an "AS
 * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * rights and limitations under the License.
 *
 * The Original Code is mozilla.org code.
 *
 * The Initial Developer of the Original Code is Netscape
 * Communications Corporation.  Portions created by Netscape are
 * Copyright (C) 1998 Netscape Communications Corporation. All
 * Rights Reserved.
 *
 * Contributor(s): 
 */

#ifndef nsIDTD_h___
#define nsIDTD_h___

/**
 * MODULE NOTES:
 * @update  gess 7/20/98
 * 
 * This interface defines standard interface for DTD's. Note that this isn't HTML specific.
 * DTD's have several primary functions within the parser system:
 *		1) To coordinate the consumption of an input stream via the parser
 *		2) To serve as proxy to represent the containment rules of the underlying document
 *		3) To offer autodetection services to the parser (mainly for doc conversion)
 *         
 */

#include "nsISupports.h"
#include "prtypes.h"
#include "nsITokenizer.h"

#define NS_IDTD_IID \
 { 0xa6cf9053, 0x15b3, 0x11d2,{0x93, 0x2e, 0x00, 0x80, 0x5f, 0x8a, 0xdd, 0x32}}

enum eAutoDetectResult {
  eUnknownDetect, 
  eValidDetect,   
  ePrimaryDetect,
  eInvalidDetect
};

enum nsDTDMode {
  eDTDMode_unknown=0,
  eDTDMode_quirks,        //pre 4.0 versions
  eDTDMode_strict,
  eDTDMode_autodetect
};


class nsIParser;
class CToken;
class nsIURI;
class nsString;
class nsIContentSink;
class CParserContext;

class nsIDTD : public nsISupports {
  public:

    static const nsIID& GetIID() { static nsIID iid = NS_IDTD_IID; return iid; }
  
    virtual const nsIID&  GetMostDerivedIID(void) const =0;

    /**
     * Call this method if you want the DTD to construct a clone of itself.
     * @update	gess7/23/98
     * @param 
     * @return
     */
    virtual nsresult CreateNewInstance(nsIDTD** aInstancePtrResult)=0;

    /**
     * This method is called to determine if the given DTD can parse
     * a document in a given source-type. 
     * NOTE: Parsing always assumes that the end result will involve
     *       storing the result in the main content model.
     * @update	gess6/24/98
     * @param   aContentType -- string representing type of doc to be converted (ie text/html)
     * @return  TRUE if this DTD can satisfy the request; FALSE otherwise.
     */
    virtual eAutoDetectResult CanParse(CParserContext& aParserContext,nsString& aBuffer, PRInt32 aVersion)=0;

    /**
     * Called by the parser just before the parsing process begins
     * @update	gess5/18/98
     * @param	aFilename--string that contains name of file being parsed (if applicable)
     * @return  
     */
    NS_IMETHOD WillBuildModel(  const CParserContext& aParserContext,nsIContentSink* aSink=0)=0;

    /**
     * Called by the parser after the parsing process has concluded
     * @update	gess5/18/98
     * @param	anErrorCode - contains error code resulting from parse process
     * @return
     */
    NS_IMETHOD DidBuildModel(nsresult anErrorCode,PRBool aNotifySink,nsIParser* aParser,nsIContentSink* aSink=0)=0;

    /**
     * Called by the parser after the parsing process has concluded
     * @update	gess5/18/98
     * @param	anErrorCode - contains error code resulting from parse process
     * @return
     */
    NS_IMETHOD BuildModel(nsIParser* aParser,nsITokenizer* aTokenizer,nsITokenObserver* anObserver=0,nsIContentSink* aSink=0)=0;
    
    /**
     *	Called during model building phase of parse process. Each token created during
	   *  the parse phase is stored in a deque (in the parser) and are passed to this method
	   *  so that the DTD can process the token. Ultimately, the DTD will transform given
	   *  token into calls onto a contentsink.
     *  @update  gess 3/25/98
     *  @param   aToken -- token object to be put into content model
	   *  @return	 error code (usually 0)
     */
    NS_IMETHOD HandleToken(CToken* aToken,nsIParser* aParser)=0;

    /**
     * 
     * @update	gess 12/20/99
     * @param   ptr-ref to (out) tokenizer
     * @return  nsresult
     */
    NS_IMETHOD  GetTokenizer(nsITokenizer*& aTokenizer)=0;


    virtual  nsTokenAllocator* GetTokenAllocator(void)=0;

    /**
     * If the parse process gets interrupted midway, this method is called by the
	 * parser prior to resuming the process.
     * @update	gess5/18/98
     * @return	ignored
     */
    NS_IMETHOD WillResumeParse(void)=0;

    /**
     * If the parse process gets interrupted, this method is called by the parser
	 * to notify the DTD that interruption will occur.
     * @update	gess5/18/98
     * @return	ignored
     */
    NS_IMETHOD WillInterruptParse(void)=0;

    /**
     *  This method is called to determine whether or not a tag
     *  of one type can contain a tag of another type.
     *  
     *  @update  gess 3/25/98
     *  @param   aParent -- int tag of parent container
     *  @param   aChild -- int tag of child container
     *  @return  PR_TRUE if parent can contain child
     */
    virtual PRBool CanContain(PRInt32 aParent,PRInt32 aChild) const =0;

    /**
     *  This method gets called to determine whether a given 
     *  tag is itself a container
     *  
     *  @update  gess 3/25/98
     *  @param   aTag -- tag to test for containership
     *  @return  PR_TRUE if given tag can contain other tags
     */
    virtual PRBool IsContainer(PRInt32 aTag) const=0;

    /**
     * Use this id you want to stop the building content model
     * --------------[ Sets DTD to STOP mode ]----------------
     * It's recommended to use this method in accordance with
     * the parser's terminate() method.
     *
     * @update	harishd 07/22/99
     * @param 
     * @return
     */
    virtual nsresult  Terminate(nsIParser* aParser=nsnull) = 0;

/* XXX Temporary measure, pending further work by RickG  */
    
    /**
     * Give rest of world access to our tag enums, so that CanContain(), etc,
     * become useful.
     */
    NS_IMETHOD StringTagToIntTag(nsString &aTag, PRInt32* aIntTag) const =0;

    NS_IMETHOD IntTagToStringTag(PRInt32 aIntTag, nsString& aTag) const =0;

    NS_IMETHOD ConvertEntityToUnicode(const nsString& aEntity, PRInt32* aUnicode) const =0;

    virtual PRBool  IsBlockElement(PRInt32 aTagID,PRInt32 aParentID) const=0;
    virtual PRBool  IsInlineElement(PRInt32 aTagID,PRInt32 aParentID) const=0;

};



#endif /* nsIDTD_h___ */