/*
    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
 * Solidity parser.
 */

#pragma once

#include "libsolidity/AST.h"

namespace dev
{
namespace solidity
{

class Scanner;

class Parser
{
public:
	ASTPointer<SourceUnit> parse(std::shared_ptr<Scanner> const& _scanner);
	std::shared_ptr<std::string const> const& getSourceName() const;

private:
	class ASTNodeFactory;

	/// Start position of the current token
	int getPosition() const;
	/// End position of the current token
	int getEndPosition() const;

	struct VarDeclParserOptions {
		VarDeclParserOptions() {}
		bool allowVar = false;
		bool isStateVariable = false;
		bool allowIndexed = false;
		bool allowEmptyName = false;
	};

	///@{
	///@name Parsing functions for the AST nodes
	ASTPointer<ImportDirective> parseImportDirective();
	ASTPointer<ContractDefinition> parseContractDefinition();
	ASTPointer<InheritanceSpecifier> parseInheritanceSpecifier();
	Declaration::Visibility parseVisibilitySpecifier(Token::Value _token);
	ASTPointer<FunctionDefinition> parseFunctionDefinition(ASTString const* _contractName);
	ASTPointer<StructDefinition> parseStructDefinition();
	ASTPointer<EnumDefinition> parseEnumDefinition();
	ASTPointer<EnumDeclaration> parseEnumDeclaration();
	ASTPointer<VariableDeclaration> parseVariableDeclaration(VarDeclParserOptions const& _options = VarDeclParserOptions());
	ASTPointer<ModifierDefinition> parseModifierDefinition();
	ASTPointer<EventDefinition> parseEventDefinition();
	ASTPointer<ModifierInvocation> parseModifierInvocation();
	ASTPointer<Identifier> parseIdentifier();
	ASTPointer<TypeName> parseTypeName(bool _allowVar);
	ASTPointer<Mapping> parseMapping();
	ASTPointer<ParameterList> parseParameterList(bool _allowEmpty = true, bool _allowIndexed = false);
	ASTPointer<Block> parseBlock();
	ASTPointer<Statement> parseStatement();
	ASTPointer<IfStatement> parseIfStatement();
	ASTPointer<WhileStatement> parseWhileStatement();
	ASTPointer<ForStatement> parseForStatement();
	ASTPointer<Statement> parseVarDefOrExprStmt();
	ASTPointer<VariableDefinition> parseVariableDefinition();
	ASTPointer<ExpressionStatement> parseExpressionStatement();
	ASTPointer<Expression> parseExpression();
	ASTPointer<Expression> parseBinaryExpression(int _minPrecedence = 4);
	ASTPointer<Expression> parseUnaryExpression();
	ASTPointer<Expression> parseLeftHandSideExpression();
	ASTPointer<Expression> parsePrimaryExpression();
	std::vector<ASTPointer<Expression>> parseFunctionCallListArguments();
	std::pair<std::vector<ASTPointer<Expression>>, std::vector<ASTPointer<ASTString>>> parseFunctionCallArguments();
	///@}

	///@{
	///@name Helper functions

	/// Peeks ahead in the scanner to determine if a variable definition is going to follow
	bool peekVariableDefinition();

	/// If current token value is not _value, throw exception otherwise advance token.
	void expectToken(Token::Value _value);
	Token::Value expectAssignmentOperator();
	ASTPointer<ASTString> expectIdentifierToken();
	ASTPointer<ASTString> peekIdentifierToken();
	ASTPointer<ASTString> getLiteralAndAdvance();
	///@}

	/// Creates an empty ParameterList at the current location (used if parameters can be omitted).
	ASTPointer<ParameterList> createEmptyParameterList();

	/// Creates a @ref ParserError exception and annotates it with the current position and the
	/// given @a _description.
	ParserError createParserError(std::string const& _description) const;

	std::shared_ptr<Scanner> m_scanner;
	/// Flag that signifies whether '_' is parsed as a PlaceholderStatement or a regular identifier.
	bool m_insideModifier = false;
};

}
}