/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/* vim: set ts=8 sts=2 et sw=2 tw=80: */

/* 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 nsVariant_h

#define nsVariant_h

#include "nsIVariant.h"

#include "nsStringFwd.h"

#include "mozilla/Attributes.h"

#include "nsCycleCollectionParticipant.h"

/**

 * Map the nsAUTF8String, nsUTF8String classes to the nsACString and

 * nsCString classes respectively for now.  These defines need to be removed

 * once Jag lands his nsUTF8String implementation.

 */

#define nsAUTF8String nsACString

#define nsUTF8String nsCString

#define PromiseFlatUTF8String PromiseFlatCString

/**

 * nsDiscriminatedUnion is a class that nsIVariant implementors can use

 * to hold the underlying data.

 */

class nsDiscriminatedUnion

{

public:

  nsDiscriminatedUnion()

    : mType(nsIDataType::VTYPE_EMPTY)

  {

    u.mInt8Value = '\0';

  }

  nsDiscriminatedUnion(const nsDiscriminatedUnion&) = delete;

  nsDiscriminatedUnion(nsDiscriminatedUnion&&) = delete;

  ~nsDiscriminatedUnion() { Cleanup(); }

  nsDiscriminatedUnion& operator=(const nsDiscriminatedUnion&) = delete;

  nsDiscriminatedUnion& operator=(nsDiscriminatedUnion&&) = delete;

  void Cleanup();

  uint16_t GetType() const { return mType; }

  MOZ_MUST_USE nsresult ConvertToInt8(uint8_t* aResult) const;

  MOZ_MUST_USE nsresult ConvertToInt16(int16_t* aResult) const;

  MOZ_MUST_USE nsresult ConvertToInt32(int32_t* aResult) const;

  MOZ_MUST_USE nsresult ConvertToInt64(int64_t* aResult) const;

  MOZ_MUST_USE nsresult ConvertToUint8(uint8_t* aResult) const;

  MOZ_MUST_USE nsresult ConvertToUint16(uint16_t* aResult) const;

  MOZ_MUST_USE nsresult ConvertToUint32(uint32_t* aResult) const;

  MOZ_MUST_USE nsresult ConvertToUint64(uint64_t* aResult) const;

  MOZ_MUST_USE nsresult ConvertToFloat(float* aResult) const;

  MOZ_MUST_USE nsresult ConvertToDouble(double* aResult) const;

  MOZ_MUST_USE nsresult ConvertToBool(bool* aResult) const;

  MOZ_MUST_USE nsresult ConvertToChar(char* aResult) const;

  MOZ_MUST_USE nsresult ConvertToWChar(char16_t* aResult) const;

  MOZ_MUST_USE nsresult ConvertToID(nsID* aResult) const;

  MOZ_MUST_USE nsresult ConvertToAString(nsAString& aResult) const;

  MOZ_MUST_USE nsresult ConvertToAUTF8String(nsAUTF8String& aResult) const;

  MOZ_MUST_USE nsresult ConvertToACString(nsACString& aResult) const;

  MOZ_MUST_USE nsresult ConvertToString(char** aResult) const;

  MOZ_MUST_USE nsresult ConvertToWString(char16_t** aResult) const;

  MOZ_MUST_USE nsresult ConvertToStringWithSize(uint32_t* aSize, char** aStr) const;

  MOZ_MUST_USE nsresult ConvertToWStringWithSize(uint32_t* aSize, char16_t** aStr) const;

  MOZ_MUST_USE nsresult ConvertToISupports(nsISupports** aResult) const;

  MOZ_MUST_USE nsresult ConvertToInterface(nsIID** aIID, void** aInterface) const;

  MOZ_MUST_USE nsresult ConvertToArray(uint16_t* aType, nsIID* aIID,

                                       uint32_t* aCount, void** aPtr) const;

  MOZ_MUST_USE nsresult SetFromVariant(nsIVariant* aValue);

  void SetFromInt8(uint8_t aValue);

  void SetFromInt16(int16_t aValue);

  void SetFromInt32(int32_t aValue);

  void SetFromInt64(int64_t aValue);

  void SetFromUint8(uint8_t aValue);

  void SetFromUint16(uint16_t aValue);

  void SetFromUint32(uint32_t aValue);

  void SetFromUint64(uint64_t aValue);

  void SetFromFloat(float aValue);

  void SetFromDouble(double aValue);

  void SetFromBool(bool aValue);

  void SetFromChar(char aValue);

  void SetFromWChar(char16_t aValue);

  void SetFromID(const nsID& aValue);

  void SetFromAString(const nsAString& aValue);

  void SetFromDOMString(const nsAString& aValue);

  void SetFromAUTF8String(const nsAUTF8String& aValue);

  void SetFromACString(const nsACString& aValue);

  MOZ_MUST_USE nsresult SetFromString(const char* aValue);

  MOZ_MUST_USE nsresult SetFromWString(const char16_t* aValue);

  void SetFromISupports(nsISupports* aValue);

  void SetFromInterface(const nsIID& aIID, nsISupports* aValue);

  MOZ_MUST_USE nsresult SetFromArray(uint16_t aType, const nsIID* aIID,

                                     uint32_t aCount, void* aValue);

  MOZ_MUST_USE nsresult SetFromStringWithSize(uint32_t aSize,

                                              const char* aValue);

  MOZ_MUST_USE nsresult SetFromWStringWithSize(uint32_t aSize,

                                               const char16_t* aValue);

  // Like SetFromWStringWithSize, but leaves the string uninitialized. It does

  // does write the null-terminator.

  void AllocateWStringWithSize(uint32_t aSize);

  void SetToVoid();

  void SetToEmpty();

  void SetToEmptyArray();

  void Traverse(nsCycleCollectionTraversalCallback& aCb) const;

private:

  MOZ_MUST_USE nsresult

  ToManageableNumber(nsDiscriminatedUnion* aOutData) const;

  void FreeArray();

  MOZ_MUST_USE bool String2ID(nsID* aPid) const;

  MOZ_MUST_USE nsresult ToString(nsACString& aOutString) const;

public:

  union

  {

    int8_t         mInt8Value;

    int16_t        mInt16Value;

    int32_t        mInt32Value;

    int64_t        mInt64Value;

    uint8_t        mUint8Value;

    uint16_t       mUint16Value;

    uint32_t       mUint32Value;

    uint64_t       mUint64Value;

    float          mFloatValue;

    double         mDoubleValue;

    bool           mBoolValue;

    char           mCharValue;

    char16_t       mWCharValue;

    nsIID          mIDValue;

    nsAString*     mAStringValue;

    nsAUTF8String* mUTF8StringValue;

    nsACString*    mCStringValue;

    struct

    {

      // This is an owning reference that cannot be an nsCOMPtr because

      // nsDiscriminatedUnion needs to be POD.  AddRef/Release are manually

      // called on this.

      nsISupports* MOZ_OWNING_REF mInterfaceValue;

      nsIID        mInterfaceID;

    } iface;

    struct

    {

      nsIID        mArrayInterfaceID;

      void*        mArrayValue;

      uint32_t     mArrayCount;

      uint16_t     mArrayType;

    } array;

    struct

    {

      char*        mStringValue;

      uint32_t     mStringLength;

    } str;

    struct

    {

      char16_t*    mWStringValue;

      uint32_t     mWStringLength;

    } wstr;

  } u;

  uint16_t       mType;

};

/**

 * nsVariant implements the generic variant support. The xpcom module registers

 * a factory (see NS_VARIANT_CONTRACTID in nsIVariant.idl) that will create

 * these objects. They are created 'empty' and 'writable'.

 *

 * nsIVariant users won't usually need to see this class.

 */

class nsVariantBase : public nsIWritableVariant

{

public:

  NS_DECL_NSIVARIANT

  NS_DECL_NSIWRITABLEVARIANT

  nsVariantBase();

protected:

  ~nsVariantBase() {};

  nsDiscriminatedUnion mData;

  bool mWritable;

};

class nsVariant final : public nsVariantBase

{

public:

  NS_DECL_ISUPPORTS

  nsVariant() {};

private:

  ~nsVariant() {};

};

class nsVariantCC final : public nsVariantBase

{

public:

  NS_DECL_CYCLE_COLLECTING_ISUPPORTS

  NS_DECL_CYCLE_COLLECTION_CLASS(nsVariantCC)

  nsVariantCC() {};

private:

  ~nsVariantCC() {};

};

/**

 * Users of nsIVariant should be using the contractID and not this CID.

 *  - see NS_VARIANT_CONTRACTID in nsIVariant.idl.

 */

#define NS_VARIANT_CID \

{ /* 0D6EA1D0-879C-11d5-90EF-0010A4E73D9A */ \

    0xd6ea1d0,                               \

    0x879c,                                  \

    0x11d5,                                  \

    {0x90, 0xef, 0x0, 0x10, 0xa4, 0xe7, 0x3d, 0x9a}}

#endif // nsVariant_h