/* A visitor that writes parse trees.

 Copyright (c) 2002-2014 The Regents of the University of California
 All rights reserved.
 Permission is hereby granted, without written agreement and without
 license or royalty fees, to use, copy, modify, and distribute this
 software and its documentation for any purpose, provided that the above
 copyright notice and the following two paragraphs appear in all copies
 of this software.

 IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA OR RESEARCH IN MOTION
 LIMITED BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT, SPECIAL,
 INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OF THIS
 SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF CALIFORNIA
 OR RESEARCH IN MOTION LIMITED HAVE BEEN ADVISED OF THE POSSIBILITY OF
 SUCH DAMAGE.

 THE UNIVERSITY OF CALIFORNIA AND RESEARCH IN MOTION LIMITED
 SPECIFICALLY DISCLAIM ANY WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
 PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS ON AN "AS IS"
 BASIS, AND THE UNIVERSITY OF CALIFORNIA AND RESEARCH IN MOTION
 LIMITED HAVE NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES,
 ENHANCEMENTS, OR MODIFICATIONS.


 */
package ptolemy.data.expr;

import java.io.PrintWriter;
import java.io.StringWriter;
import java.util.Iterator;
import java.util.List;

import ptolemy.data.StringToken;
import ptolemy.kernel.util.IllegalActionException;

///////////////////////////////////////////////////////////////////
//// ParseTreeWriter

/**
 This class implements a visitor that writes parse trees in the
 expression language.

 @author Steve Neuendorffer
 @version $Id$
 @since Ptolemy II 2.1
 @Pt.ProposedRating Red (neuendor)
 @Pt.AcceptedRating Red (cxh)
 @see ptolemy.data.expr.ASTPtRootNode
 */
public class ParseTreeWriter extends AbstractParseTreeVisitor {
    public void displayParseTree(ASTPtRootNode root) {
        _writer = new PrintWriter(System.out);

        try {
            root.visit(this);
        } catch (IllegalActionException ex) {
            _writer.println(ex);
            ex.printStackTrace(_writer);
        }
    }

    /** Produce an expression for this parse tree.
     *  @param root The root of the parse tree.
     *  @return The expression.
     *  @exception IllegalActionException If the parse tree has an error.
     */
    public String parseTreeToExpression(ASTPtRootNode root)
            throws IllegalActionException {
        StringWriter writer = new StringWriter();
        _writer = new PrintWriter(writer);
        root.visit(this);
        return writer.toString();
    }

    /** Return an expression for this parse tree, or a description
     *  of the exception if an exception occurs.
     *  @param root The root of the parse tree.
     *  @return The expression.
     */
    public String printParseTree(ASTPtRootNode root) {
        StringWriter writer = new StringWriter();
        _writer = new PrintWriter(writer);

        try {
            root.visit(this);
        } catch (IllegalActionException ex) {
            _writer.println(ex);
            ex.printStackTrace(_writer);
        }

        return writer.toString();
    }

    /** Specify whether the expression to write is in string mode.
     *  FIXME string mode has only been implemented for leaf and sum nodes.
     *  @param stringMode True to put the expression to write in string mode.
     */
    public void setStringMode(boolean stringMode) {
        _isStringMode = stringMode;
    }

    ///////////////////////////////////////////////////////////////////
    ////                         public methods                    ////
    @Override
    public void visitArrayConstructNode(ASTPtArrayConstructNode node)
            throws IllegalActionException {
        _writer.print("{");
        _printChildrenSeparated(node, ", ");
        _writer.print("}");
    }

    @Override
    public void visitBitwiseNode(ASTPtBitwiseNode node)
            throws IllegalActionException {
        _writer.print("(");
        _printChildrenSeparated(node, node.getOperator().image);
        _writer.print(")");
    }

    @Override
    public void visitFunctionApplicationNode(ASTPtFunctionApplicationNode node)
            throws IllegalActionException {
        _printChild(node, 0);
        _writer.print("(");

        int n = node.jjtGetNumChildren();

        for (int i = 1; i < n - 1; ++i) {
            _printChild(node, i);
            _writer.print(", ");
        }

        if (n > 1) {
            _printChild(node, n - 1);
        }

        _writer.print(")");
    }

    @Override
    public void visitFunctionDefinitionNode(ASTPtFunctionDefinitionNode node)
            throws IllegalActionException {
        // This code is duplicated with the FunctionToken.
        _writer.print("(function(");

        List args = node.getArgumentNameList();
        ptolemy.data.type.Type[] argTypes = node.getArgumentTypes();
        int n = args.size();

        for (int i = 0; i < n; i++) {
            if (i > 0) {
                _writer.print(", ");
            }

            _writer.print((String) args.get(i));

            ptolemy.data.type.Type type = argTypes[i];

            if (type != ptolemy.data.type.BaseType.GENERAL) {
                _writer.print(":");
                _writer.print(type.toString());
            }
        }

        _writer.print(") ");
        node.getExpressionTree().visit(this);
        _writer.print(")");
    }

    @Override
    public void visitFunctionalIfNode(ASTPtFunctionalIfNode node)
            throws IllegalActionException {
        _writer.print("(");
        _printChild(node, 0);
        _writer.print("?");
        _printChild(node, 1);
        _writer.print(":");
        _printChild(node, 2);
        _writer.print(")");
    }

    @Override
    public void visitLeafNode(ASTPtLeafNode node)
            throws IllegalActionException {
        if (node.isConstant() && node.isEvaluated()) {
            ptolemy.data.Token token = node.getToken();
            if (_isStringMode && (token instanceof StringToken)) {
                _writer.print(((StringToken) token).stringValue());
            } else {
                _writer.print(token.toString());
            }
        } else {
            _writer.print(node.getName());
        }
    }

    @Override
    public void visitLogicalNode(ASTPtLogicalNode node)
            throws IllegalActionException {
        _writer.print("(");
        _printChildrenSeparated(node, node.getOperator().image);
        _writer.print(")");
    }

    @Override
    public void visitMatrixConstructNode(ASTPtMatrixConstructNode node)
            throws IllegalActionException {
        _writer.print("[");

        int n = 0;
        int rowCount = node.getRowCount();
        int columnCount = node.getColumnCount();

        for (int i = 0; i < rowCount; i++) {
            for (int j = 0; j < columnCount; j++) {
                _printChild(node, n++);

                if (j < columnCount - 1) {
                    _writer.print(", ");
                }
            }

            if (i < rowCount - 1) {
                _writer.print("; ");
            }
        }

        _writer.print("]");
    }

    @Override
    public void visitMethodCallNode(ASTPtMethodCallNode node)
            throws IllegalActionException {
        _printChild(node, 0);
        _writer.print(".");
        _writer.print(node.getMethodName());
        _writer.print("(");

        if (node.jjtGetNumChildren() > 1) {
            _printChild(node, 1);

            for (int i = 2; i < node.jjtGetNumChildren(); i++) {
                _writer.print(", ");
                _printChild(node, i);
            }
        }

        _writer.print(")");
    }

    @Override
    public void visitPowerNode(ASTPtPowerNode node)
            throws IllegalActionException {
        _printChildrenSeparated(node, "^");
    }

    @Override
    public void visitProductNode(ASTPtProductNode node)
            throws IllegalActionException {
        _writer.print("(");
        _printChildrenSeparated(node, node.getLexicalTokenList());
        _writer.print(")");
    }

    @Override
    public void visitRecordConstructNode(ASTPtRecordConstructNode node)
            throws IllegalActionException {
        Iterator names = node.getFieldNames().iterator();
        if (node instanceof ASTPtOrderedRecordConstructNode) {
            _writer.print("[");
        } else {
            _writer.print("{");
        }

        if (node.jjtGetNumChildren() > 0) {
            _writer.print(names.next());
            _writer.print("=");
            _printChild(node, 0);

            for (int i = 1; i < node.jjtGetNumChildren(); i++) {
                _writer.print(", ");
                _writer.print(names.next());
                _writer.print("=");
                _printChild(node, i);
            }
        }

        if (node instanceof ASTPtOrderedRecordConstructNode) {
            _writer.print("]");
        } else {
            _writer.print("}");
        }
    }

    @Override
    public void visitRelationalNode(ASTPtRelationalNode node)
            throws IllegalActionException {
        _writer.print("(");
        _printChildrenSeparated(node, node.getOperator().image);
        _writer.print(")");
    }

    @Override
    public void visitShiftNode(ASTPtShiftNode node)
            throws IllegalActionException {
        _writer.print("(");
        _printChildrenSeparated(node, node.getOperator().image);
        _writer.print(")");
    }

    @Override
    public void visitSumNode(ASTPtSumNode node) throws IllegalActionException {
        if (!_isStringMode) {
            _writer.print("(");
        }
        _printChildrenSeparated(node, node.getLexicalTokenList());
        if (!_isStringMode) {
            _writer.print(")");
        }
    }

    @Override
    public void visitUnaryNode(ASTPtUnaryNode node)
            throws IllegalActionException {
        if (node.isMinus()) {
            _writer.print("-");
        } else if (node.isNot()) {
            _writer.print("!");
        } else {
            _writer.print("~");
        }

        _printChild(node, 0);
    }

    protected PrintWriter _writer = new PrintWriter(System.out);

    private void _printChild(ASTPtRootNode node, int index)
            throws IllegalActionException {
        ASTPtRootNode child = (ASTPtRootNode) node.jjtGetChild(index);
        child.visit(this);
    }

    private void _printChildrenSeparated(ASTPtRootNode node, List separatorList)
            throws IllegalActionException {
        Iterator separators = separatorList.iterator();

        if (node.jjtGetNumChildren() > 0) {
            _printChild(node, 0);

            for (int i = 1; i < node.jjtGetNumChildren(); i++) {
                Token separator = (Token) separators.next();
                if (!_isStringMode || separator.image != null) {
                    _writer.print(separator.image);
                }
                _printChild(node, i);
            }
        }
    }

    private void _printChildrenSeparated(ASTPtRootNode node, String string)
            throws IllegalActionException {
        if (node.jjtGetNumChildren() > 0) {
            _printChild(node, 0);

            for (int i = 1; i < node.jjtGetNumChildren(); i++) {
                _writer.print(string);
                _printChild(node, i);
            }
        }
    }

    /** Indicates if string mode is on. */
    private boolean _isStringMode = false;

}