/*
	This file is part of solidity.

	solidity 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.

	solidity 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 solidity.  If not, see <http://www.gnu.org/licenses/>.
*/
// SPDX-License-Identifier: GPL-3.0
/**
 * @author Alex Beregszaszi
 * @date 2017
 * Component that translates Solidity code into Yul.
 */

#pragma once

#include <libsolidity/interface/OptimiserSettings.h>
#include <libsolidity/ast/ASTForward.h>
#include <libsolidity/ast/CallGraph.h>
#include <libsolidity/codegen/ir/IRGenerationContext.h>
#include <libsolidity/codegen/YulUtilFunctions.h>

#include <liblangutil/CharStreamProvider.h>
#include <liblangutil/EVMVersion.h>

#include <string>

namespace solidity::frontend
{

class SourceUnit;

class IRGenerator
{
public:
	using ExecutionContext = IRGenerationContext::ExecutionContext;

	IRGenerator(
		langutil::EVMVersion _evmVersion,
		RevertStrings _revertStrings,
		OptimiserSettings _optimiserSettings,
		std::map<std::string, unsigned> _sourceIndices,
		langutil::DebugInfoSelection const& _debugInfoSelection,
		langutil::CharStreamProvider const* _soliditySourceProvider
	):
		m_evmVersion(_evmVersion),
		m_optimiserSettings(_optimiserSettings),
		m_context(
			_evmVersion,
			ExecutionContext::Creation,
			_revertStrings,
			std::move(_optimiserSettings),
			std::move(_sourceIndices),
			_debugInfoSelection,
			_soliditySourceProvider
		),
		m_utils(_evmVersion, m_context.revertStrings(), m_context.functionCollector())
	{}

	/// Generates and returns the IR code, in unoptimized and optimized form
	/// (or just pretty-printed, depending on the optimizer settings).
	std::pair<std::string, std::string> run(
		ContractDefinition const& _contract,
		bytes const& _cborMetadata,
		std::map<ContractDefinition const*, std::string_view const> const& _otherYulSources
	);

private:
	std::string generate(
		ContractDefinition const& _contract,
		bytes const& _cborMetadata,
		std::map<ContractDefinition const*, std::string_view const> const& _otherYulSources
	);
	std::string generate(Block const& _block);

	/// Generates code for all the functions from the function generation queue.
	/// The resulting code is stored in the function collector in IRGenerationContext.
	/// @returns A set of ast nodes of the generated functions.
	std::set<FunctionDefinition const*> generateQueuedFunctions();
	/// Generates  all the internal dispatch functions necessary to handle any function that could
	/// possibly be called via a pointer.
	/// @return The content of the dispatch for reuse in runtime code. Reuse is necessary because
	/// pointers to functions can be passed from the creation code in storage variables.
	InternalDispatchMap generateInternalDispatchFunctions(ContractDefinition const& _contract);
	/// Generates code for and returns the name of the function.
	std::string generateFunction(FunctionDefinition const& _function);
	std::string generateModifier(
		ModifierInvocation const& _modifierInvocation,
		FunctionDefinition const& _function,
		std::string const& _nextFunction
	);
	std::string generateFunctionWithModifierInner(FunctionDefinition const& _function);
	/// Generates a getter for the given declaration and returns its name
	std::string generateGetter(VariableDeclaration const& _varDecl);

	/// Generates the external part (ABI decoding and encoding) of a function or getter.
	std::string generateExternalFunction(ContractDefinition const& _contract, FunctionType const& _functionType);

	/// Generates code that assigns the initial value of the respective type.
	std::string generateInitialAssignment(VariableDeclaration const& _varDecl);

	/// Generates constructors for all contracts in the inheritance hierarchy of
	/// @a _contract
	/// If there are user defined constructors, their body will be included in the implicit constructor's body.
	void generateConstructors(ContractDefinition const& _contract);

	/// Evaluates constructor's arguments for all base contracts (listed in inheritance specifiers) of
	/// @a _contract
	/// @returns Pair of expressions needed to evaluate params and list of parameters in a map contract -> params
	std::pair<std::string, std::map<ContractDefinition const*, std::vector<std::string>>>
	evaluateConstructorArguments(ContractDefinition const& _contract);

	/// Initializes state variables of
	/// @a _contract
	/// @returns Source code to initialize state variables
	std::string initStateVariables(ContractDefinition const& _contract);

	std::string deployCode(ContractDefinition const& _contract);
	std::string callValueCheck();

	std::string dispatchRoutine(ContractDefinition const& _contract);

	/// @a _useMemoryGuard If true, use a memory guard, allowing the optimiser
	/// to perform memory optimizations.
	std::string memoryInit(bool _useMemoryGuard);

	void resetContext(ContractDefinition const& _contract, ExecutionContext _context);

	std::string dispenseLocationComment(ASTNode const& _node);

	langutil::EVMVersion const m_evmVersion;
	OptimiserSettings const m_optimiserSettings;

	IRGenerationContext m_context;
	YulUtilFunctions m_utils;
};

}