/* 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"
#include "mozilla/dom/FromParser.h"

class nsIContent;
class nsHtml5TreeOpExecutor;
class nsHtml5StateSnapshot;
class nsHtml5DocumentBuilder;

enum eHtml5TreeOperation {
  eTreeOpUninitialized,
  // main HTML5 ops
  eTreeOpAppend,
  eTreeOpDetach,
  eTreeOpAppendChildrenToNewParent,
  eTreeOpFosterParent,
  eTreeOpAppendToDocument,
  eTreeOpAddAttributes,
  eTreeOpDocumentMode,
  eTreeOpCreateElementNetwork,
  eTreeOpCreateElementNotNetwork,
  eTreeOpSetFormElement,
  eTreeOpAppendText,
  eTreeOpAppendIsindexPrompt,
  eTreeOpFosterParentText,
  eTreeOpAppendComment,
  eTreeOpAppendCommentToDocument,
  eTreeOpAppendDoctypeToDocument,
  eTreeOpGetDocumentFragmentForTemplate,
  // Gecko-specific on-pop ops
  eTreeOpMarkAsBroken,
  eTreeOpRunScript,
  eTreeOpRunScriptAsyncDefer,
  eTreeOpPreventScriptExecution,
  eTreeOpDoneAddingChildren,
  eTreeOpDoneCreatingElement,
  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:
    /**
     * Atom is used inside the parser core are either static atoms that are
     * the same as Gecko-wide static atoms or they are dynamic atoms scoped by
     * both thread and parser to a particular nsHtml5AtomTable. In order to
     * such scoped atoms coming into contact with the rest of Gecko, atoms
     * that are about to exit the parser must go through this method which
     * reobtains dynamic atoms from the Gecko-global atom table.
     *
     * @param aAtom a potentially parser-scoped atom
     * @return an nsIAtom that's pointer comparable on the main thread with
     *         other not-parser atoms.
     */
    static inline already_AddRefed<nsIAtom> Reget(nsIAtom* aAtom)
    {
      if (!aAtom || aAtom->IsStaticAtom()) {
        return dont_AddRef(aAtom);
      }
      nsAutoString str;
      aAtom->ToString(str);
      return do_GetAtom(str);
    }

    static nsresult AppendTextToTextNode(const char16_t* aBuffer,
                                         uint32_t aLength,
                                         nsIContent* aTextNode,
                                         nsHtml5DocumentBuilder* aBuilder);

    static nsresult AppendText(const char16_t* aBuffer,
                               uint32_t aLength,
                               nsIContent* aParent,
                               nsHtml5DocumentBuilder* aBuilder);

    static nsresult Append(nsIContent* aNode,
                           nsIContent* aParent,
                           nsHtml5DocumentBuilder* aBuilder);

    static nsresult AppendToDocument(nsIContent* aNode,
                                     nsHtml5DocumentBuilder* aBuilder);

    static void Detach(nsIContent* aNode, nsHtml5DocumentBuilder* aBuilder);

    static nsresult AppendChildrenToNewParent(nsIContent* aNode,
                                              nsIContent* aParent,
                                              nsHtml5DocumentBuilder* aBuilder);

    static nsresult FosterParent(nsIContent* aNode,
                                 nsIContent* aParent,
                                 nsIContent* aTable,
                                 nsHtml5DocumentBuilder* aBuilder);

    static nsresult AddAttributes(nsIContent* aNode,
                                  nsHtml5HtmlAttributes* aAttributes,
                                  nsHtml5DocumentBuilder* aBuilder);

    static nsIContent* CreateElement(int32_t aNs,
                                     nsIAtom* aName,
                                     nsHtml5HtmlAttributes* aAttributes,
                                     mozilla::dom::FromParser aFromParser,
                                     nsHtml5DocumentBuilder* aBuilder);

    static void SetFormElement(nsIContent* aNode, nsIContent* aParent);

    static nsresult AppendIsindexPrompt(nsIContent* parent,
                                        nsHtml5DocumentBuilder* aBuilder);

    static nsresult FosterParentText(nsIContent* aStackParent,
                                     char16_t* aBuffer,
                                     uint32_t aLength,
                                     nsIContent* aTable,
                                     nsHtml5DocumentBuilder* aBuilder);

    static nsresult AppendComment(nsIContent* aParent,
                                  char16_t* aBuffer,
                                  int32_t aLength,
                                  nsHtml5DocumentBuilder* aBuilder);

    static nsresult AppendCommentToDocument(char16_t* aBuffer,
                                           int32_t aLength,
                                           nsHtml5DocumentBuilder* aBuilder);

    static nsresult AppendDoctypeToDocument(nsIAtom* aName,
                                            const nsAString& aPublicId,
                                            const nsAString& aSystemId,
                                            nsHtml5DocumentBuilder* aBuilder);

    static nsIContent* GetDocumentFragmentForTemplate(nsIContent* aNode);

    static void PreventScriptExecution(nsIContent* aNode);

    static void DoneAddingChildren(nsIContent* aNode);

    static void DoneCreatingElement(nsIContent* aNode);

    static void SvgLoad(nsIContent* aNode);

    static void MarkMalformedIfScript(nsIContent* aNode);

    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, nsIContentHandle* 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 = static_cast<nsIContent**>(aNode);
    }

    inline void Init(eHtml5TreeOperation aOpCode, 
                     nsIContentHandle* aNode,
                     nsIContentHandle* 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 = static_cast<nsIContent**>(aNode);
      mTwo.node = static_cast<nsIContent**>(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,
                     nsIContentHandle* aNode,
                     nsIContentHandle* aParent,
                     nsIContentHandle* 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 = static_cast<nsIContent**>(aNode);
      mTwo.node = static_cast<nsIContent**>(aParent);
      mThree.node = static_cast<nsIContent**>(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(nsIContentHandle* 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 = static_cast<nsIContent**>(aNode);
      mTwo.state = nullptr;
    }
    
    inline void Init(int32_t aNamespace, 
                     nsIAtom* aName, 
                     nsHtml5HtmlAttributes* aAttributes,
                     nsIContentHandle* 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 = static_cast<nsIContent**>(aTarget);
      mTwo.atom = aName;
      if (aAttributes == nsHtml5HtmlAttributes::EMPTY_ATTRIBUTES) {
        mThree.attributes = nullptr;
      } else {
        mThree.attributes = aAttributes;
      }
    }

    inline void Init(eHtml5TreeOperation aOpCode, 
                     char16_t* aBuffer, 
                     int32_t aLength, 
                     nsIContentHandle* aStackParent,
                     nsIContentHandle* 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 = static_cast<nsIContent**>(aStackParent);
      mTwo.unicharPtr = aBuffer;
      mThree.node = static_cast<nsIContent**>(aTable);
      mFour.integer = aLength;
    }

    inline void Init(eHtml5TreeOperation aOpCode, 
                     char16_t* aBuffer, 
                     int32_t aLength, 
                     nsIContentHandle* 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 = static_cast<nsIContent**>(aParent);
      mTwo.unicharPtr = aBuffer;
      mFour.integer = aLength;
    }

    inline void Init(eHtml5TreeOperation aOpCode, 
                     char16_t* 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(nsIContentHandle* 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 = static_cast<nsIContent**>(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(nsIContentHandle* aElement,
                     const char* aMsgId,
                     nsIAtom* aAtom,
                     nsIAtom* aOtherAtom)
    {
      NS_PRECONDITION(mOpCode == eTreeOpUninitialized,
        "Op code must be uninitialized when initializing.");
      mOpCode = eTreeOpAddError;
      mOne.node = static_cast<nsIContent**>(aElement);
      mTwo.charPtr = (char*)aMsgId;
      mThree.atom = aAtom;
      mFour.atom = aOtherAtom;
    }

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

    inline void Init(nsIContentHandle* 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.");

      char16_t* str = NS_StringCloneData(aString);
      mOpCode = aOpCode;
      mOne.unicharPtr = str;
    }
    
    inline void Init(eHtml5TreeOperation aOpCode,
                     nsIContentHandle* 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 = static_cast<nsIContent**>(aNode);
      mFour.integer = aInt;
    }

    inline void InitAddClass(nsIContentHandle* aNode, const char16_t* 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 = static_cast<nsIContent**>(aNode);
      mTwo.unicharPtr = (char16_t*)aClass;
    }

    inline void InitAddLineNumberId(nsIContentHandle* 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 = static_cast<nsIContent**>(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);

  private:
    // 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;
      char16_t*                      unicharPtr;
      char*                           charPtr;
      nsHtml5TreeOperationStringPair* stringPair;
      nsAHtml5TreeBuilderState*       state;
      int32_t                         integer;
    }                   mOne, mTwo, mThree, mFour;
};

#endif // nsHtml5TreeOperation_h