/* 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/. */
 
#ifndef nsHtml5TreeOperation_h__
#define nsHtml5TreeOperation_h__

#include "nsHtml5DocumentMode.h"
#include "nsHtml5HtmlAttributes.h"
#include "nsXPCOMStrings.h"

class nsIContent;
class nsHtml5TreeOpExecutor;
class nsHtml5StateSnapshot;

enum eHtml5TreeOperation {
#ifdef DEBUG
  eTreeOpUninitialized,
#endif
  // main HTML5 ops
  eTreeOpAppend,
  eTreeOpDetach,
  eTreeOpAppendChildrenToNewParent,
  eTreeOpFosterParent,
  eTreeOpAppendToDocument,
  eTreeOpAddAttributes,
  eTreeOpDocumentMode,
  eTreeOpCreateElementNetwork,
  eTreeOpCreateElementNotNetwork,
  eTreeOpSetFormElement,
  eTreeOpAppendText,
  eTreeOpAppendIsindexPrompt,
  eTreeOpFosterParentText,
  eTreeOpAppendComment,
  eTreeOpAppendCommentToDocument,
  eTreeOpAppendDoctypeToDocument,
  // Gecko-specific on-pop ops
  eTreeOpMarkAsBroken,
  eTreeOpRunScript,
  eTreeOpRunScriptAsyncDefer,
  eTreeOpPreventScriptExecution,
  eTreeOpDoneAddingChildren,
  eTreeOpDoneCreatingElement,
  eTreeOpFlushPendingAppendNotifications,
  eTreeOpSetDocumentCharset,
  eTreeOpNeedsCharsetSwitchTo,
  eTreeOpUpdateStyleSheet,
  eTreeOpProcessMeta,
  eTreeOpProcessOfflineManifest,
  eTreeOpMarkMalformedIfScript,
  eTreeOpStreamEnded,
  eTreeOpSetStyleLineNumber,
  eTreeOpSetScriptLineNumberAndFreeze,
  eTreeOpSvgLoad,
  eTreeOpMaybeComplainAboutCharset,
  eTreeOpAddClass,
  eTreeOpAddViewSourceHref,
  eTreeOpAddError,
  eTreeOpAddLineNumberId,
  eTreeOpAddErrorAtom,
  eTreeOpAddErrorTwoAtoms,
  eTreeOpStartLayout
};

class nsHtml5TreeOperationStringPair {
  private:
    nsString mPublicId;
    nsString mSystemId;
  public:
    nsHtml5TreeOperationStringPair(const nsAString& aPublicId, 
                                   const nsAString& aSystemId)
      : mPublicId(aPublicId)
      , mSystemId(aSystemId) {
      MOZ_COUNT_CTOR(nsHtml5TreeOperationStringPair);
    }
    
    ~nsHtml5TreeOperationStringPair() {
      MOZ_COUNT_DTOR(nsHtml5TreeOperationStringPair);    
    }
    
    inline void Get(nsAString& aPublicId, nsAString& aSystemId) {
      aPublicId.Assign(mPublicId);
      aSystemId.Assign(mSystemId);
    }
};

class nsHtml5TreeOperation {

  public:
    nsHtml5TreeOperation();

    ~nsHtml5TreeOperation();

    inline void Init(eHtml5TreeOperation aOpCode) {
      NS_PRECONDITION(mOpCode == eTreeOpUninitialized,
        "Op code must be uninitialized when initializing.");
      mOpCode = aOpCode;
    }

    inline void Init(eHtml5TreeOperation aOpCode, nsIContent** aNode) {
      NS_PRECONDITION(mOpCode == eTreeOpUninitialized,
        "Op code must be uninitialized when initializing.");
      NS_PRECONDITION(aNode, "Initialized tree op with null node.");
      mOpCode = aOpCode;
      mOne.node = aNode;
    }

    inline void Init(eHtml5TreeOperation aOpCode, 
                     nsIContent** aNode,
                     nsIContent** aParent) {
      NS_PRECONDITION(mOpCode == eTreeOpUninitialized,
        "Op code must be uninitialized when initializing.");
      NS_PRECONDITION(aNode, "Initialized tree op with null node.");
      NS_PRECONDITION(aParent, "Initialized tree op with null parent.");
      mOpCode = aOpCode;
      mOne.node = aNode;
      mTwo.node = aParent;
    }
    
    inline void Init(eHtml5TreeOperation aOpCode, 
                     const nsACString& aString,
                     int32_t aInt32) {
      NS_PRECONDITION(mOpCode == eTreeOpUninitialized,
        "Op code must be uninitialized when initializing.");

      int32_t len = aString.Length();
      char* str = new char[len + 1];
      const char* start = aString.BeginReading();
      for (int32_t i = 0; i < len; ++i) {
        str[i] = start[i];
      }
      str[len] = '\0';

      mOpCode = aOpCode;
      mOne.charPtr = str;
      mFour.integer = aInt32;
    }

    inline void Init(eHtml5TreeOperation aOpCode,
                     const nsACString& aString,
                     int32_t aInt32,
                     int32_t aLineNumber) {
      Init(aOpCode, aString, aInt32);
      mTwo.integer = aLineNumber;
    }

    inline void Init(eHtml5TreeOperation aOpCode,
                     nsIContent** aNode,
                     nsIContent** aParent, 
                     nsIContent** aTable) {
      NS_PRECONDITION(mOpCode == eTreeOpUninitialized,
        "Op code must be uninitialized when initializing.");
      NS_PRECONDITION(aNode, "Initialized tree op with null node.");
      NS_PRECONDITION(aParent, "Initialized tree op with null parent.");
      NS_PRECONDITION(aTable, "Initialized tree op with null table.");
      mOpCode = aOpCode;
      mOne.node = aNode;
      mTwo.node = aParent;
      mThree.node = aTable;
    }

    inline void Init(nsHtml5DocumentMode aMode) {
      NS_PRECONDITION(mOpCode == eTreeOpUninitialized,
        "Op code must be uninitialized when initializing.");
      mOpCode = eTreeOpDocumentMode;
      mOne.mode = aMode;
    }
    
    inline void InitScript(nsIContent** aNode) {
      NS_PRECONDITION(mOpCode == eTreeOpUninitialized,
        "Op code must be uninitialized when initializing.");
      NS_PRECONDITION(aNode, "Initialized tree op with null node.");
      mOpCode = eTreeOpRunScript;
      mOne.node = aNode;
      mTwo.state = nullptr;
    }
    
    inline void Init(int32_t aNamespace, 
                     nsIAtom* aName, 
                     nsHtml5HtmlAttributes* aAttributes,
                     nsIContent** aTarget,
                     bool aFromNetwork) {
      NS_PRECONDITION(mOpCode == eTreeOpUninitialized,
        "Op code must be uninitialized when initializing.");
      NS_PRECONDITION(aName, "Initialized tree op with null name.");
      NS_PRECONDITION(aTarget, "Initialized tree op with null target node.");
      mOpCode = aFromNetwork ?
                eTreeOpCreateElementNetwork :
                eTreeOpCreateElementNotNetwork;
      mFour.integer = aNamespace;
      mOne.node = aTarget;
      mTwo.atom = aName;
      if (aAttributes == nsHtml5HtmlAttributes::EMPTY_ATTRIBUTES) {
        mThree.attributes = nullptr;
      } else {
        mThree.attributes = aAttributes;
      }
    }

    inline void Init(eHtml5TreeOperation aOpCode, 
                     PRUnichar* aBuffer, 
                     int32_t aLength, 
                     nsIContent** aStackParent,
                     nsIContent** aTable) {
      NS_PRECONDITION(mOpCode == eTreeOpUninitialized,
        "Op code must be uninitialized when initializing.");
      NS_PRECONDITION(aBuffer, "Initialized tree op with null buffer.");
      mOpCode = aOpCode;
      mOne.node = aStackParent;
      mTwo.unicharPtr = aBuffer;
      mThree.node = aTable;
      mFour.integer = aLength;
    }

    inline void Init(eHtml5TreeOperation aOpCode, 
                     PRUnichar* aBuffer, 
                     int32_t aLength, 
                     nsIContent** aParent) {
      NS_PRECONDITION(mOpCode == eTreeOpUninitialized,
        "Op code must be uninitialized when initializing.");
      NS_PRECONDITION(aBuffer, "Initialized tree op with null buffer.");
      mOpCode = aOpCode;
      mOne.node = aParent;
      mTwo.unicharPtr = aBuffer;
      mFour.integer = aLength;
    }

    inline void Init(eHtml5TreeOperation aOpCode, 
                     PRUnichar* aBuffer, 
                     int32_t aLength) {
      NS_PRECONDITION(mOpCode == eTreeOpUninitialized,
        "Op code must be uninitialized when initializing.");
      NS_PRECONDITION(aBuffer, "Initialized tree op with null buffer.");
      mOpCode = aOpCode;
      mTwo.unicharPtr = aBuffer;
      mFour.integer = aLength;
    }
    
    inline void Init(nsIContent** aElement,
                     nsHtml5HtmlAttributes* aAttributes) {
      NS_PRECONDITION(mOpCode == eTreeOpUninitialized,
        "Op code must be uninitialized when initializing.");
      NS_PRECONDITION(aElement, "Initialized tree op with null element.");
      mOpCode = eTreeOpAddAttributes;
      mOne.node = aElement;
      mTwo.attributes = aAttributes;
    }
    
    inline void Init(nsIAtom* aName, 
                     const nsAString& aPublicId, 
                     const nsAString& aSystemId) {
      NS_PRECONDITION(mOpCode == eTreeOpUninitialized,
        "Op code must be uninitialized when initializing.");
      mOpCode = eTreeOpAppendDoctypeToDocument;
      mOne.atom = aName;
      mTwo.stringPair = new nsHtml5TreeOperationStringPair(aPublicId, aSystemId);
    }
    
    inline void Init(nsIContent** aElement,
                     const char* aMsgId,
                     nsIAtom* aAtom,
                     nsIAtom* aOtherAtom) {
      NS_PRECONDITION(mOpCode == eTreeOpUninitialized,
        "Op code must be uninitialized when initializing.");
      mOpCode = eTreeOpAddError;
      mOne.node = aElement;
      mTwo.charPtr = (char*)aMsgId;
      mThree.atom = aAtom;
      mFour.atom = aOtherAtom;
    }

    inline void Init(nsIContent** aElement,
                     const char* aMsgId,
                     nsIAtom* aAtom) {
      Init(aElement, aMsgId, aAtom, nullptr);
    }

    inline void Init(nsIContent** aElement,
                     const char* aMsgId) {
      Init(aElement, aMsgId, nullptr, nullptr);
    }

    inline void Init(const char* aMsgId,
                     bool aError,
                     int32_t aLineNumber) {
      NS_PRECONDITION(mOpCode == eTreeOpUninitialized,
        "Op code must be uninitialized when initializing.");
      mOpCode = eTreeOpMaybeComplainAboutCharset;
      mOne.charPtr = const_cast<char*>(aMsgId);
      mTwo.integer = aError;
      mThree.integer = aLineNumber;
    }

    inline void Init(eHtml5TreeOperation aOpCode, const nsAString& aString) {
      NS_PRECONDITION(mOpCode == eTreeOpUninitialized,
        "Op code must be uninitialized when initializing.");

      PRUnichar* str = NS_StringCloneData(aString);
      mOpCode = aOpCode;
      mOne.unicharPtr = str;
    }
    
    inline void Init(eHtml5TreeOperation aOpCode,
                     nsIContent** aNode,
                     int32_t aInt) {
      NS_PRECONDITION(mOpCode == eTreeOpUninitialized,
        "Op code must be uninitialized when initializing.");
      NS_PRECONDITION(aNode, "Initialized tree op with null node.");
      mOpCode = aOpCode;
      mOne.node = aNode;
      mFour.integer = aInt;
    }

    inline void InitAddClass(nsIContent** aNode, const PRUnichar* aClass) {
      NS_PRECONDITION(mOpCode == eTreeOpUninitialized,
        "Op code must be uninitialized when initializing.");
      NS_PRECONDITION(aNode, "Initialized tree op with null node.");
      NS_PRECONDITION(aClass, "Initialized tree op with null string.");
      // aClass must be a literal string that does not need freeing
      mOpCode = eTreeOpAddClass;
      mOne.node = aNode;
      mTwo.unicharPtr = (PRUnichar*)aClass;
    }

    inline void InitAddLineNumberId(nsIContent** aNode,
                                    const int32_t aLineNumber) {
      NS_PRECONDITION(mOpCode == eTreeOpUninitialized,
        "Op code must be uninitialized when initializing.");
      NS_PRECONDITION(aNode, "Initialized tree op with null node.");
      NS_PRECONDITION(aLineNumber > 0, "Initialized tree op with line number.");
      // aClass must be a literal string that does not need freeing
      mOpCode = eTreeOpAddLineNumberId;
      mOne.node = aNode;
      mFour.integer = aLineNumber;
    }

    inline bool IsRunScript() {
      return mOpCode == eTreeOpRunScript;
    }
    
    inline void SetSnapshot(nsAHtml5TreeBuilderState* aSnapshot, int32_t aLine) {
      NS_ASSERTION(IsRunScript(), 
        "Setting a snapshot for a tree operation other than eTreeOpRunScript!");
      NS_PRECONDITION(aSnapshot, "Initialized tree op with null snapshot.");
      mTwo.state = aSnapshot;
      mFour.integer = aLine;
    }

    nsresult Perform(nsHtml5TreeOpExecutor* aBuilder, nsIContent** aScriptElement);

    inline already_AddRefed<nsIAtom> Reget(nsIAtom* aAtom) {
      if (!aAtom || aAtom->IsStaticAtom()) {
        return aAtom;
      }
      nsAutoString str;
      aAtom->ToString(str);
      return do_GetAtom(str);
    }

  private:

    nsresult AppendTextToTextNode(const PRUnichar* aBuffer,
                                  uint32_t aLength,
                                  nsIContent* aTextNode,
                                  nsHtml5TreeOpExecutor* aBuilder);

    nsresult AppendText(const PRUnichar* aBuffer,
                        uint32_t aLength,
                        nsIContent* aParent,
                        nsHtml5TreeOpExecutor* aBuilder);

    nsresult Append(nsIContent* aNode,
                    nsIContent* aParent,
                    nsHtml5TreeOpExecutor* aBuilder);

    nsresult AppendToDocument(nsIContent* aNode,
                              nsHtml5TreeOpExecutor* aBuilder);
  
    // possible optimization:
    // Make the queue take items the size of pointer and make the op code
    // decide how many operands it dequeues after it.
    eHtml5TreeOperation mOpCode;
    union {
      nsIContent**                    node;
      nsIAtom*                        atom;
      nsHtml5HtmlAttributes*          attributes;
      nsHtml5DocumentMode             mode;
      PRUnichar*                      unicharPtr;
      char*                           charPtr;
      nsHtml5TreeOperationStringPair* stringPair;
      nsAHtml5TreeBuilderState*       state;
      int32_t                         integer;
    }                   mOne, mTwo, mThree, mFour;
};

#endif // nsHtml5TreeOperation_h__
