package node.stmtNode;
import node.*;
import node.exprNode.*;
import env.*;
import type.*;
import type.basicType.*;
import runEnv.*;
import runEnv.basicValue.*;
import text.*;
import java.io.*;

public class BuiltinNode extends StmtNode {

	private ExprListNode actualParams;

	public BuiltinNode( ExprListNode actualParams ) {
		this.actualParams = actualParams;
		}
	
	public String toString() {
		return 
			"builtin( " + actualParams + " )";
		}

	public void genEnv( Env env ) {
		super.genEnv( env );
		actualParams.genEnv( env );
		}

	public void setType() {
		}

	public void checkType() {
		actualParams.checkType();
		}

	public void eval( RunEnv runEnv ) throws ReturnException {
		Multiple params = actualParams.evalMultiple( runEnv );
		builtin( params );
		}
	
	private void builtin( Multiple params ) throws ReturnException {
		String name = params.getValue( 0 ).stringValue();
		if ( "read".equals( name ) ) {
			try {
				throw new ReturnException( new CharValue( ( char ) System.in.read() ) );
				}
			catch (IOException exception ) {
				throw new Error( "Unable to read system input" );
				}
			}
		else if ( "print".equals( name ) ) {
			String s = params.getValue( 1 ).stringValue();
			Print.interp().print( s );
			}
		else if ( "println".equals( name ) ) {
			String s = params.getValue( 1 ).stringValue();
			Print.interp().println( s );
			}
		else if ( "chr".equals( name ) ) {
			int value = params.getValue( 1 ).intValue();
			throw new ReturnException( new CharValue( ( char ) value ) );
			}
		else if ( "ord".equals( name ) ) {
			char value = params.getValue( 1 ).charValue();
			throw new ReturnException( new IntValue( ( int ) value ) );
			}
		else
			throw new Error( "Unknown builtin( " + name + ", ... )" );
		}

	}