package org.lilystudio.javascript.statement;
import java.io.IOException;
import java.io.Writer;
import org.lilystudio.javascript.Environment;
import org.lilystudio.javascript.IExpression;
import org.lilystudio.javascript.INode;
import org.lilystudio.javascript.IStatement;
import org.lilystudio.javascript.expression.InbuildLiteral;
import org.lilystudio.javascript.scope.Constant;
import org.lilystudio.javascript.scope.Scope;
import org.mozilla.javascript.Node;
import org.mozilla.javascript.ScriptOrFnNode;
import org.mozilla.javascript.Token;
/**
* 循环语句节点
*
* @version 1.0.0, 2010/01/01
* @author 欧阳先伟
* @since Common 0.1
*/
public class LoopStatement extends Statement implements IBodyStatement {
/** 循环的类型 */
private int tokenType;
/** 循环的开始节点，用于for语句 */
private INode startNode;
/** 循环的条件表达式 */
private IExpression checkExpression;
/** 循环的周期结束表达式，用于for语句 */
private IExpression endExpression;
/** 循环体语句 */
private IStatement bodyStatement;
/**
* 创建循环语句节点
*
* @param node
* 语句子节点对应的rhino节点
* @param root
* 语句子节点对应的rhino根节点
* @param scope
* 语句子节点生存域
*/
public LoopStatement(Node node, ScriptOrFnNode root, Scope scope) {
super(node);
Node childNode = node.getFirstChild();
switch (childNode.getType()) {
case Token.EXPR_VOID:
tokenType = Token.FOR;
startNode = addExpression(childNode.getFirstChild(), root, scope);
childNode = childNode.getNext();
break;
case Token.VAR:
tokenType = Token.FOR;
startNode = addStatement(childNode, root, scope);
childNode = childNode.getNext();
break;
}
if (childNode.getType() == Token.TARGET) {
bodyStatement = addStatement(childNode.getNext(), root, scope);
childNode = bodyStatement.getNext().getNext();
checkExpression = addExpression(childNode.getFirstChild(), root, scope);
if (tokenType == 0) {
tokenType = Token.DO;
}
} else if (childNode.getType() == Token.GOTO) {
bodyStatement = addStatement(childNode.getNext().getNext(), root, scope);
childNode = bodyStatement.getNext().getNext();
if (childNode.getType() == Token.EXPR_VOID) {
tokenType = Token.FOR;
endExpression = addExpression(childNode.getFirstChild(), root, scope);
childNode = childNode.getNext().getNext();
}
childNode = childNode.getNext();
if (childNode.getType() == Token.TARGET) {
checkExpression = addExpression(childNode.getNext().getFirstChild(),
root, scope);
tokenType = Token.FOR;
} else {
checkExpression = addExpression(childNode.getFirstChild(), root, scope);
if (tokenType == 0) {
tokenType = Token.WHILE;
}
}
}
}
public boolean isNeedLeftSeparator() {
return true;
}
public boolean isNeedRightSeparator() {
switch (tokenType) {
case Token.DO:
return true;
default:
return bodyStatement.isNeedRightSeparator();
}
}
public void write(Writer writer, Environment env) throws IOException {
switch (tokenType) {
case Token.DO:
case Token.WHILE:
if (checkExpression instanceof InbuildLiteral) {
Constant literal = ((InbuildLiteral) checkExpression).getLiteral();
if (literal.getString(false).equals("true")) {
literal.dec(false);
writer.write("for(;;)");
bodyStatement.write(writer, env);
break;
}
}
if (tokenType == Token.DO) {
writer.write("do");
if (bodyStatement.isNeedLeftSeparator()) {
writer.write(" ");
}
bodyStatement.write(writer, env);
if (bodyStatement.isNeedRightSeparator()) {
writer.write(";");
}
writer.write("while(");
checkExpression.write(writer, env);
writer.write(")");
} else {
writer.write("while(");
checkExpression.write(writer, env);
writer.write(")");
bodyStatement.write(writer, env);
}
break;
default:
writer.write("for(");
if (startNode != null) {
startNode.write(writer, env);
}
writer.write(";");
if (checkExpression instanceof InbuildLiteral) {
Constant literal = ((InbuildLiteral) checkExpression).getLiteral();
if (literal.getString(false).equals("true")) {
literal.dec(false);
}
} else {
checkExpression.write(writer, env);
}
writer.write(";");
if (endExpression != null) {
endExpression.write(writer, env);
}
writer.write(")");
bodyStatement.write(writer, env);
}
}
public boolean isIfBody() {
return tokenType != Token.DO && bodyStatement instanceof IBodyStatement
&& ((IBodyStatement) bodyStatement).isIfBody();
}
}