michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "nsSMILValue.h"
michael@0: #include "nsDebug.h"
michael@0: #include <string.h>
michael@0: 
michael@0: //----------------------------------------------------------------------
michael@0: // Public methods
michael@0: 
michael@0: nsSMILValue::nsSMILValue(const nsISMILType* aType)
michael@0:   : mType(nsSMILNullType::Singleton())
michael@0: {
michael@0:   if (!aType) {
michael@0:     NS_ERROR("Trying to construct nsSMILValue with null mType pointer");
michael@0:     return;
michael@0:   }
michael@0: 
michael@0:   InitAndCheckPostcondition(aType);
michael@0: }
michael@0: 
michael@0: nsSMILValue::nsSMILValue(const nsSMILValue& aVal)
michael@0:   : mType(nsSMILNullType::Singleton())
michael@0: {
michael@0:   InitAndCheckPostcondition(aVal.mType);
michael@0:   mType->Assign(*this, aVal);
michael@0: }
michael@0: 
michael@0: const nsSMILValue&
michael@0: nsSMILValue::operator=(const nsSMILValue& aVal)
michael@0: {
michael@0:   if (&aVal == this)
michael@0:     return *this;
michael@0: 
michael@0:   if (mType != aVal.mType) {
michael@0:     DestroyAndReinit(aVal.mType);
michael@0:   }
michael@0: 
michael@0:   mType->Assign(*this, aVal);
michael@0: 
michael@0:   return *this;
michael@0: }
michael@0: 
michael@0: bool
michael@0: nsSMILValue::operator==(const nsSMILValue& aVal) const
michael@0: {
michael@0:   if (&aVal == this)
michael@0:     return true;
michael@0: 
michael@0:   return mType == aVal.mType && mType->IsEqual(*this, aVal);
michael@0: }
michael@0: 
michael@0: void
michael@0: nsSMILValue::Swap(nsSMILValue& aOther)
michael@0: {
michael@0:   nsSMILValue tmp;
michael@0:   memcpy(&tmp,    &aOther, sizeof(nsSMILValue));  // tmp    = aOther
michael@0:   memcpy(&aOther, this,    sizeof(nsSMILValue));  // aOther = this
michael@0:   memcpy(this,    &tmp,    sizeof(nsSMILValue));  // this   = tmp
michael@0: 
michael@0:   // |tmp| is about to die -- we need to clear its mType, so that its
michael@0:   // destructor doesn't muck with the data we just transferred out of it.
michael@0:   tmp.mType = nsSMILNullType::Singleton();
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: nsSMILValue::Add(const nsSMILValue& aValueToAdd, uint32_t aCount)
michael@0: {
michael@0:   if (aValueToAdd.mType != mType) {
michael@0:     NS_ERROR("Trying to add incompatible types");
michael@0:     return NS_ERROR_FAILURE;
michael@0:   }
michael@0: 
michael@0:   return mType->Add(*this, aValueToAdd, aCount);
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: nsSMILValue::SandwichAdd(const nsSMILValue& aValueToAdd)
michael@0: {
michael@0:   if (aValueToAdd.mType != mType) {
michael@0:     NS_ERROR("Trying to add incompatible types");
michael@0:     return NS_ERROR_FAILURE;
michael@0:   }
michael@0: 
michael@0:   return mType->SandwichAdd(*this, aValueToAdd);
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: nsSMILValue::ComputeDistance(const nsSMILValue& aTo, double& aDistance) const
michael@0: {
michael@0:   if (aTo.mType != mType) {
michael@0:     NS_ERROR("Trying to calculate distance between incompatible types");
michael@0:     return NS_ERROR_FAILURE;
michael@0:   }
michael@0: 
michael@0:   return mType->ComputeDistance(*this, aTo, aDistance);
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: nsSMILValue::Interpolate(const nsSMILValue& aEndVal,
michael@0:                          double aUnitDistance,
michael@0:                          nsSMILValue& aResult) const
michael@0: {
michael@0:   if (aEndVal.mType != mType) {
michael@0:     NS_ERROR("Trying to interpolate between incompatible types");
michael@0:     return NS_ERROR_FAILURE;
michael@0:   }
michael@0: 
michael@0:   if (aResult.mType != mType) {
michael@0:     // Outparam has wrong type
michael@0:     aResult.DestroyAndReinit(mType);
michael@0:   }
michael@0: 
michael@0:   return mType->Interpolate(*this, aEndVal, aUnitDistance, aResult);
michael@0: }
michael@0: 
michael@0: //----------------------------------------------------------------------
michael@0: // Helper methods
michael@0: 
michael@0: // Wrappers for nsISMILType::Init & ::Destroy that verify their postconditions
michael@0: void
michael@0: nsSMILValue::InitAndCheckPostcondition(const nsISMILType* aNewType)
michael@0: {
michael@0:   aNewType->Init(*this);
michael@0:   NS_ABORT_IF_FALSE(mType == aNewType,
michael@0:                     "Post-condition of Init failed. nsSMILValue is invalid");
michael@0: }
michael@0:                 
michael@0: void
michael@0: nsSMILValue::DestroyAndCheckPostcondition()
michael@0: {
michael@0:   mType->Destroy(*this);
michael@0:   NS_ABORT_IF_FALSE(IsNull(), "Post-condition of Destroy failed. "
michael@0:                     "nsSMILValue not null after destroying");
michael@0: }
michael@0: 
michael@0: void
michael@0: nsSMILValue::DestroyAndReinit(const nsISMILType* aNewType)
michael@0: {
michael@0:   DestroyAndCheckPostcondition();
michael@0:   InitAndCheckPostcondition(aNewType);
michael@0: }