//
// 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.
//
// DeclReplacer.cpp --
//
// Author           : Aaron B. Moss
// Created On       : Wed May 8 13:00:00 2019
// Last Modified By : Andrew Beach
// Last Modified On : Thr Sep 15 11:55:00 2022
// Update Count     : 2
//

#include "DeclReplacer.hpp"

#include "Expr.hpp"
#include "Pass.hpp"
#include "Type.hpp"

namespace ast {

namespace DeclReplacer {

namespace {
	struct DeclReplacer {
	private:
		const DeclMap & declMap;
		const TypeMap & typeMap;
		bool debug;

	public:
		DeclReplacer( const DeclMap & declMap, const TypeMap & typeMap, bool debug )
			: declMap( declMap ), typeMap( typeMap ), debug( debug )
		{}

		const ast::VariableExpr * previsit( const ast::VariableExpr * );
		const ast::TypeInstType * previsit( const ast::TypeInstType * );
	};

	struct VarExprReplacer {
	private:
		const ExprMap & exprMap;

	public:
		VarExprReplacer( const ExprMap & exprMap ) : exprMap( exprMap ) {}

		const Expr * postvisit( const VariableExpr * );
	};
} // namespace

const ast::Node * replace( const ast::Node * node, const DeclMap & declMap, const TypeMap & typeMap, bool debug ) {
	if(!node) return nullptr;
	Pass<DeclReplacer> replacer = { declMap, typeMap, debug };
	return node->accept( replacer );
}

const ast::Node * replace( const ast::Node * node, const DeclMap & declMap, bool debug ) {
	TypeMap typeMap;
	return replace( node, declMap, typeMap, debug );
}

const ast::Node * replace( const ast::Node * node, const TypeMap & typeMap, bool debug ) {
	DeclMap declMap;
	return replace( node, declMap, typeMap, debug );
}

const ast::Node * replace( const ast::Node * node, const ExprMap & exprMap ) {
	Pass<VarExprReplacer> replacer = {exprMap};
	return node->accept( replacer );
}

namespace {
	// replace variable with new node from decl map
	const ast::VariableExpr * DeclReplacer::previsit( const VariableExpr * varExpr ) {
		// xxx - assertions and parameters aren't accounted for in this... (i.e. they aren't inserted into the map when it's made, only DeclStmts are)
		if ( !declMap.count( varExpr->var ) ) return varExpr;

		auto replacement = declMap.at( varExpr->var );
		if ( debug ) {
			std::cerr << "replacing variable reference: "
				<< (void*)varExpr->var.get() << " " << varExpr->var
				<< " with " << (void*)replacement << " " << replacement
				<< std::endl;
		}
		auto nexpr = mutate(varExpr);
		nexpr->var = replacement;
		return nexpr;
	}

	const TypeInstType * DeclReplacer::previsit( const TypeInstType * inst ) {
		if ( !typeMap.count( inst->base ) ) return inst;

		auto replacement = typeMap.at( inst->base );
		if ( debug ) {
			std::cerr << "replacing type reference: "
				<< (void*)inst->base.get() << " " << inst->base
				<< " with " << (void*)replacement << " " << replacement
				<< std::endl;
		}
		auto ninst = mutate(inst);
		ninst->base = replacement;
		return ninst;
	}

	const Expr * VarExprReplacer::postvisit( const VariableExpr * expr ) {
		if ( !exprMap.count( expr->var ) ) return expr;
		return exprMap.at( expr->var );
	}
} // namespace

} // namespace DeclReplacer

} // namespace ast

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