/*
	This file is part of cpp-ethereum.

	cpp-ethereum is free software: you can redistribute it and/or modify
	it under the terms of the GNU General Public License as published by
	the Free Software Foundation, either version 3 of the License, or
	(at your option) any later version.

	cpp-ethereum is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	GNU General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with cpp-ethereum.  If not, see <http://www.gnu.org/licenses/>.
*/
/**
 * @author Christian <c@ethdev.com>
 * @date 2014
 * Routines used by both the compiler and the expression compiler.
 */

#include <libsolidity/CompilerUtils.h>
#include <libsolidity/AST.h>
#include <libevmcore/Instruction.h>

using namespace std;

namespace dev
{
namespace solidity
{

void CompilerUtils::moveToStackVariable(VariableDeclaration const& _variable)
{
	unsigned const stackPosition = m_context.baseToCurrentStackOffset(m_context.getBaseStackOffsetOfVariable(_variable));
	unsigned const size = _variable.getType()->getSizeOnStack();
	// move variable starting from its top end in the stack
	if (stackPosition - size + 1 > 16)
		BOOST_THROW_EXCEPTION(CompilerError() << errinfo_sourceLocation(_variable.getLocation())
											  << errinfo_comment("Stack too deep."));
	for (unsigned i = 0; i < size; ++i)
		m_context << eth::swapInstruction(stackPosition - size + 1) << eth::Instruction::POP;
}

void CompilerUtils::copyToStackTop(unsigned _stackDepth, Type const& _type)
{
	if (_stackDepth > 16)
		BOOST_THROW_EXCEPTION(CompilerError() << errinfo_comment("Stack too deep."));
	unsigned const size = _type.getSizeOnStack();
	for (unsigned i = 0; i < size; ++i)
		m_context << eth::dupInstruction(_stackDepth);
}

void CompilerUtils::popStackElement(Type const& _type)
{
	unsigned const size = _type.getSizeOnStack();
	for (unsigned i = 0; i < size; ++i)
		m_context << eth::Instruction::POP;
}

unsigned CompilerUtils::getSizeOnStack(vector<shared_ptr<Type const>> const& _variableTypes)
{
	unsigned size = 0;
	for (shared_ptr<Type const> const& type: _variableTypes)
		size += type->getSizeOnStack();
	return size;
}

}
}