//
// Cforall Version 1.0.0 Copyright (C) 2015 University of Waterloo
//
// The contents of this file are covered under the licence agreement in the
// file "LICENCE" distributed with Cforall.
//
// Resolver.cc -- 
//
// Author           : Richard C. Bilson
// Created On       : Sun May 17 12:17:01 2015
// Last Modified By : Peter A. Buhr
// Last Modified On : Sun Jun  7 21:50:37 2015
// Update Count     : 23
//

#include "Resolver.h"
#include "AlternativeFinder.h"
#include "Alternative.h"
#include "RenameVars.h"
#include "ResolveTypeof.h"
#include "SynTree/Statement.h"
#include "SynTree/Type.h"
#include "SynTree/Expression.h"
#include "SynTree/Initializer.h"
#include "SymTab/Indexer.h"
#include "utility.h"

#include <iostream>
using namespace std;

namespace ResolvExpr {
	class Resolver : public SymTab::Indexer {
	  public:
		Resolver() : SymTab::Indexer( false ), switchType( 0 ) {}
  
		virtual void visit( FunctionDecl *functionDecl );
		virtual void visit( ObjectDecl *functionDecl );
		virtual void visit( TypeDecl *typeDecl );

		virtual void visit( ExprStmt *exprStmt );
		virtual void visit( IfStmt *ifStmt );
		virtual void visit( WhileStmt *whileStmt );
		virtual void visit( ForStmt *forStmt );
		virtual void visit( SwitchStmt *switchStmt );
		virtual void visit( ChooseStmt *switchStmt );
		virtual void visit( CaseStmt *caseStmt );
		virtual void visit( ReturnStmt *returnStmt );

		virtual void visit( SingleInit *singleInit );
		virtual void visit( ListInit *listInit );
	  private:
		std::list< Type * > functionReturn;
		Type *initContext;
		Type *switchType;
	};

	void resolve( std::list< Declaration * > translationUnit ) {
		Resolver resolver;
		acceptAll( translationUnit, resolver );
#if 0
		resolver.print( cerr );
		for ( std::list< Declaration * >::iterator i = translationUnit.begin(); i != translationUnit.end(); ++i ) {
			(*i)->print( std::cerr );
			(*i)->accept( resolver );
		} // for
#endif
	}

	Expression *resolveInVoidContext( Expression *expr, const SymTab::Indexer &indexer ) {
		TypeEnvironment env;
		return resolveInVoidContext( expr, indexer, env );
	}

	namespace {
		void finishExpr( Expression *expr, const TypeEnvironment &env ) {
			expr->set_env( new TypeSubstitution );
			env.makeSubstitution( *expr->get_env() );
		}

		Expression *findVoidExpression( Expression *untyped, const SymTab::Indexer &indexer ) {
			global_renamer.reset();
			TypeEnvironment env;
			Expression *newExpr = resolveInVoidContext( untyped, indexer, env );
			finishExpr( newExpr, env );
			return newExpr;
		}
  
		Expression *findSingleExpression( Expression *untyped, const SymTab::Indexer &indexer ) {
			TypeEnvironment env;
			AlternativeFinder finder( indexer, env );
			finder.find( untyped );
#if 0
			if ( finder.get_alternatives().size() != 1 ) {
				std::cout << "untyped expr is ";
				untyped->print( std::cout );
				std::cout << std::endl << "alternatives are:";
				for ( std::list< Alternative >::const_iterator i = finder.get_alternatives().begin(); i != finder.get_alternatives().end(); ++i ) {
					i->print( std::cout );
				} // for
			} // if
#endif
			assert( finder.get_alternatives().size() == 1 );
			Alternative &choice = finder.get_alternatives().front();
			Expression *newExpr = choice.expr->clone();
			finishExpr( newExpr, choice.env );
			return newExpr;
		}

		bool isIntegralType( Type *type ) {
			if ( dynamic_cast< EnumInstType * >( type ) ) {
				return true;
			} else if ( BasicType *bt = dynamic_cast< BasicType * >( type ) ) {
				return bt->isInteger();
			} else {
				return false;
			} // if
		}
  
		Expression *findIntegralExpression( Expression *untyped, const SymTab::Indexer &indexer ) {
			TypeEnvironment env;
			AlternativeFinder finder( indexer, env );
			finder.find( untyped );
#if 0
			if ( finder.get_alternatives().size() != 1 ) {
				std::cout << "untyped expr is ";
				untyped->print( std::cout );
				std::cout << std::endl << "alternatives are:";
				for ( std::list< Alternative >::const_iterator i = finder.get_alternatives().begin(); i != finder.get_alternatives().end(); ++i ) {
					i->print( std::cout );
				} // for
			} // if
#endif
			Expression *newExpr = 0;
			const TypeEnvironment *newEnv = 0;
			for ( AltList::const_iterator i = finder.get_alternatives().begin(); i != finder.get_alternatives().end(); ++i ) {
				if ( i->expr->get_results().size() == 1 && isIntegralType( i->expr->get_results().front() ) ) {
					if ( newExpr ) {
						throw SemanticError( "Too many interpretations for case control expression", untyped );
					} else {
						newExpr = i->expr->clone();
						newEnv = &i->env;
					} // if
				} // if
			} // for
			if ( ! newExpr ) {
				throw SemanticError( "No interpretations for case control expression", untyped );
			} // if
			finishExpr( newExpr, *newEnv );
			return newExpr;
		}
  
	}
  
	void Resolver::visit( ObjectDecl *objectDecl ) {
		Type *new_type = resolveTypeof( objectDecl->get_type(), *this );
		objectDecl->set_type( new_type );
		initContext = new_type;
		SymTab::Indexer::visit( objectDecl );

		if ( ArrayType * at = dynamic_cast< ArrayType * >( new_type ) ){
			if ( at->get_dimension() ) {
				BasicType arrayLenType = BasicType( Type::Qualifiers(), BasicType::LongUnsignedInt );
				CastExpr *castExpr = new CastExpr( at->get_dimension(), arrayLenType.clone() );
				Expression *newExpr = findSingleExpression( castExpr, *this );
				delete at->get_dimension();
				at->set_dimension( newExpr );
			}
		}
	}
  
	void Resolver::visit( TypeDecl *typeDecl ) {
		if ( typeDecl->get_base() ) {
			Type *new_type = resolveTypeof( typeDecl->get_base(), *this );
			typeDecl->set_base( new_type );
		} // if
		SymTab::Indexer::visit( typeDecl );
	}
  
	void Resolver::visit( FunctionDecl *functionDecl ) {
#if 0
		std::cout << "resolver visiting functiondecl ";
		functionDecl->print( std::cout );
		std::cout << std::endl;
#endif
		Type *new_type = resolveTypeof( functionDecl->get_type(), *this );
		functionDecl->set_type( new_type );
		std::list< Type * > oldFunctionReturn = functionReturn;
		functionReturn.clear();
		for ( std::list< DeclarationWithType * >::const_iterator i = functionDecl->get_functionType()->get_returnVals().begin(); i != functionDecl->get_functionType()->get_returnVals().end(); ++i ) {
			functionReturn.push_back( (*i)->get_type() );
		} // for
		SymTab::Indexer::visit( functionDecl );
		functionReturn = oldFunctionReturn;
	}

	void Resolver::visit( ExprStmt *exprStmt ) {
		if ( exprStmt->get_expr() ) {
			Expression *newExpr = findVoidExpression( exprStmt->get_expr(), *this );
			delete exprStmt->get_expr();
			exprStmt->set_expr( newExpr );
		} // if
	}

	void Resolver::visit( IfStmt *ifStmt ) {
		Expression *newExpr = findSingleExpression( ifStmt->get_condition(), *this );
		delete ifStmt->get_condition();
		ifStmt->set_condition( newExpr );
		Visitor::visit( ifStmt );
	}

	void Resolver::visit( WhileStmt *whileStmt ) {
		Expression *newExpr = findSingleExpression( whileStmt->get_condition(), *this );
		delete whileStmt->get_condition();
		whileStmt->set_condition( newExpr );
		Visitor::visit( whileStmt );
	}

	void Resolver::visit( ForStmt *forStmt ) {
	    // SymTab::Indexer::visit( forStmt );
		Expression *newExpr;
	    // for statements introduce a level of scope
	    enterScope();
	    maybeAccept( forStmt->get_initialization(), *this );
		if ( forStmt->get_condition() ) {
			newExpr = findSingleExpression( forStmt->get_condition(), *this );
			delete forStmt->get_condition();
			forStmt->set_condition( newExpr );
		} // if
  
		if ( forStmt->get_increment() ) {
			newExpr = findVoidExpression( forStmt->get_increment(), *this );
			delete forStmt->get_increment();
			forStmt->set_increment( newExpr );
		} // if

	    maybeAccept( forStmt->get_condition(), *this );
	    maybeAccept( forStmt->get_increment(), *this );
	    maybeAccept( forStmt->get_body(), *this );
	    leaveScope();
	}

	template< typename SwitchClass >
	void handleSwitchStmt( SwitchClass *switchStmt, SymTab::Indexer &visitor ) {
		Expression *newExpr;
		newExpr = findIntegralExpression( switchStmt->get_condition(), visitor );
		delete switchStmt->get_condition();
		switchStmt->set_condition( newExpr );
  
		visitor.Visitor::visit( switchStmt );
	}

	void Resolver::visit( SwitchStmt *switchStmt ) {
		handleSwitchStmt( switchStmt, *this );
	}

	void Resolver::visit( ChooseStmt *switchStmt ) {
		handleSwitchStmt( switchStmt, *this );
	}

	void Resolver::visit( CaseStmt *caseStmt ) {
		Visitor::visit( caseStmt );
	}

	void Resolver::visit( ReturnStmt *returnStmt ) {
		if ( returnStmt->get_expr() ) {
			CastExpr *castExpr = new CastExpr( returnStmt->get_expr() );
			cloneAll( functionReturn, castExpr->get_results() );
			Expression *newExpr = findSingleExpression( castExpr, *this );
			delete castExpr;
			returnStmt->set_expr( newExpr );
		} // if
	}

	void Resolver::visit( SingleInit *singleInit ) {
		if ( singleInit->get_value() ) {
#if 0
			if (NameExpr * ne = dynamic_cast<NameExpr*>(singleInit->get_value())) {
				string n = ne->get_name();
				if (n == "0") {
					initContext = new BasicType(Type::Qualifiers(), 
												BasicType::SignedInt);
				} else {
					DeclarationWithType * decl = lookupId(n);
					initContext = decl->get_type();
				}
			} else if (ConstantExpr * e = 
					   dynamic_cast<ConstantExpr*>(singleInit->get_value())) {
				Constant *c = e->get_constant();
				initContext = c->get_type();
			} else {
				assert(0);
			}
#endif
			CastExpr *castExpr = new CastExpr( singleInit->get_value(), initContext->clone() );
			Expression *newExpr = findSingleExpression( castExpr, *this );
			delete castExpr;
			singleInit->set_value( newExpr );
		} // if
//	singleInit->get_value()->accept( *this );
	}

	void Resolver::visit( ListInit *listInit ) {
		Visitor::visit(listInit);
#if 0
		if ( ArrayType *at = dynamic_cast<ArrayType*>(initContext) ) {
			std::list<Initializer *>::iterator iter( listInit->begin_initializers() );
			for ( ; iter != listInit->end_initializers(); ++iter ) {
				initContext = at->get_base();
				(*iter)->accept( *this );
			} // for
		} else if ( StructInstType *st = dynamic_cast<StructInstType*>(initContext) ) {
			StructDecl *baseStruct = st->get_baseStruct();
			std::list<Declaration *>::iterator iter1( baseStruct->get_members().begin() );
			std::list<Initializer *>::iterator iter2( listInit->begin_initializers() );
			for ( ; iter1 != baseStruct->get_members().end() && iter2 != listInit->end_initializers(); ++iter2 ) {
				if ( (*iter2)->get_designators().empty() ) {
					DeclarationWithType *dt = dynamic_cast<DeclarationWithType *>( *iter1 );
					initContext = dt->get_type();
					(*iter2)->accept( *this );
					++iter1;
				} else {
					StructDecl *st = baseStruct;
					iter1 = st->get_members().begin();
					std::list<Expression *>::iterator iter3( (*iter2)->get_designators().begin() );
					for ( ; iter3 != (*iter2)->get_designators().end(); ++iter3 ) {
						NameExpr *key = dynamic_cast<NameExpr *>( *iter3 );
						assert( key );
						for ( ; iter1 != st->get_members().end(); ++iter1 ) {
							if ( key->get_name() == (*iter1)->get_name() ) {
								(*iter1)->print( cout );
								cout << key->get_name() << endl;
								ObjectDecl *fred = dynamic_cast<ObjectDecl *>( *iter1 );
								assert( fred );
								StructInstType *mary = dynamic_cast<StructInstType*>( fred->get_type() );
								assert( mary );
								st = mary->get_baseStruct();
								iter1 = st->get_members().begin();
								break;
							} // if
						}  // for
					} // for
					ObjectDecl *fred = dynamic_cast<ObjectDecl *>( *iter1 );
					assert( fred );
					initContext = fred->get_type();
					(*listInit->begin_initializers())->accept( *this );
				} // if
			} // for
		} else if ( UnionInstType *st = dynamic_cast<UnionInstType*>(initContext) ) {
			DeclarationWithType *dt = dynamic_cast<DeclarationWithType *>( *st->get_baseUnion()->get_members().begin() );
			initContext = dt->get_type();
			(*listInit->begin_initializers())->accept( *this );
		} // if
#endif
	}
} // namespace ResolvExpr

// Local Variables: //
// tab-width: 4 //
// mode: c++ //
// compile-command: "make install" //
// End: //