/*******************************************************************************
 * Copyright (c) 2005, 2007 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 
 *******************************************************************************/
/*
 * (c) 2002, 2005 xored software and others all rights reserved. http://www.xored.com
 */

package org.eclipse.dltk.ast;

import java.io.StringWriter;
import java.util.ArrayList;
import java.util.List;

import org.eclipse.dltk.core.ISourceRange;
import org.eclipse.dltk.internal.core.SourceRange;
import org.eclipse.dltk.utils.CorePrinter;

public abstract class ASTNode {
	
//	 storage for internal flags (32 bits)						BIT USAGE
	public final static int Bit1 = 0x1; 						// return type (operator) | name reference kind (name ref) | add assertion (type decl) | useful empty statement (empty statement)
	public final static int Bit2 = 0x2; 						// return type (operator) | name reference kind (name ref) | has local type (type, method, field decl)
	public final static int Bit3 = 0x4; 						// return type (operator) | name reference kind (name ref) | implicit this (this ref)
	public final static int Bit4 = 0x8; 						// return type (operator) | first assignment to local (local decl) | undocumented empty block (block, type and method decl)
	public final static int Bit5 = 0x10; 						// value for return (expression) | has all method bodies (unit) | supertype ref (type ref)
	public final static int Bit6 = 0x20; 						// depth (name ref, msg) | ignore need cast check (cast expression)
	public final static int Bit7 = 0x40; 						// depth (name ref, msg) | operator (operator) | need runtime checkcast (cast expression) | label used (labelStatement)
	public final static int Bit8 = 0x80; 						// depth (name ref, msg) | operator (operator) | unsafe cast (cast expression)
	public final static int Bit9 = 0x100; 					// depth (name ref, msg) | operator (operator) | is local type (type decl)
	public final static int Bit10= 0x200; 					// depth (name ref, msg) | operator (operator) | is anonymous type (type decl)
	public final static int Bit11 = 0x400; 					// depth (name ref, msg) | operator (operator) | is member type (type decl)
	public final static int Bit12 = 0x800; 					// depth (name ref, msg) | operator (operator) | has abstract methods (type decl)
	public final static int Bit13 = 0x1000; 				// depth (name ref, msg) | is secondary type (type decl)
	public final static int Bit14 = 0x2000; 				// strictly assigned (reference lhs)
	public final static int Bit15 = 0x4000; 				// is unnecessary cast (expression) | is varargs (type ref) | isSubRoutineEscaping (try statement)
	public final static int Bit16 = 0x8000; 				// in javadoc comment (name ref, type ref, msg)
	public final static int Bit17 = 0x10000; 				// compound assigned (reference lhs)
	public final static int Bit18 = 0x20000;				// non null (expression)				
	public final static int Bit19 = 0x40000;
	public final static int Bit20 = 0x80000; 
	public final static int Bit21 = 0x100000; 		
	public final static int Bit22 = 0x200000; 			// parenthesis count (expression)
	public final static int Bit23 = 0x400000; 			// parenthesis count (expression)
	public final static int Bit24 = 0x800000; 			// parenthesis count (expression)
	public final static int Bit25 = 0x1000000; 			// parenthesis count (expression)
	public final static int Bit26 = 0x2000000; 			// parenthesis count (expression)
	public final static int Bit27 = 0x4000000; 			// parenthesis count (expression)
	public final static int Bit28 = 0x8000000; 			// parenthesis count (expression)
	public final static int Bit29 = 0x10000000; 		// parenthesis count (expression)
	public final static int Bit30 = 0x20000000; 		// elseif (if statement) | try block exit (try statement) | fall-through (case statement)
	public final static int Bit31 = 0x40000000; 		// local declaration reachable (local decl) | ignore raw type check (type ref) | discard entire assignment (assignment)
	public final static int Bit32 = 0x80000000; 		// reachable (statement)

	public final static long Bit32L = 0x80000000L; 		
	public final static long Bit33L = 0x100000000L;
	public final static long Bit34L = 0x200000000L;
	public final static long Bit35L = 0x400000000L;
	public final static long Bit36L = 0x800000000L;
	public final static long Bit37L = 0x1000000000L;
	public final static long Bit38L = 0x2000000000L;
	public final static long Bit39L = 0x4000000000L;
	public final static long Bit40L = 0x8000000000L;
	public final static long Bit41L = 0x10000000000L;
	public final static long Bit42L = 0x20000000000L;
	public final static long Bit43L = 0x40000000000L;
	public final static long Bit44L = 0x80000000000L;
	public final static long Bit45L = 0x100000000000L;
	public final static long Bit46L = 0x200000000000L;
	public final static long Bit47L = 0x400000000000L;
	public final static long Bit48L = 0x800000000000L;
	public final static long Bit49L = 0x1000000000000L;
	public final static long Bit50L = 0x2000000000000L;
	public final static long Bit51L = 0x4000000000000L;
	public final static long Bit52L = 0x8000000000000L;
	public final static long Bit53L = 0x10000000000000L;
	public final static long Bit54L = 0x20000000000000L;
	public final static long Bit55L = 0x40000000000000L;
	public final static long Bit56L = 0x80000000000000L;
	public final static long Bit57L = 0x100000000000000L;
	public final static long Bit58L = 0x200000000000000L;
	public final static long Bit59L = 0x400000000000000L;
	public final static long Bit60L = 0x800000000000000L;
	public final static long Bit61L = 0x1000000000000000L;
	public final static long Bit62L = 0x2000000000000000L;
	public final static long Bit63L = 0x4000000000000000L;
	public final static long Bit64L = 0x8000000000000000L;	

	public final static int D_METHOD_DECL = 1;

	public final static int D_TYPE_DECL = 2;

	public final static int D_VAR_DECL = 3;

	private int sourceStart;

	private int sourceEnd;

	protected ASTNode() {
		this(0, 0);
	}

	protected ASTNode(int start, int end) {
		this.sourceStart = start;
		this.sourceEnd = end;
	}

	protected ASTNode(DLTKToken token) {
		this.sourceStart = token.getColumn();
		String tokenValue = token.getText();
		if (tokenValue != null) {
			this.sourceEnd = this.sourceStart + tokenValue.length();
		} else {
			this.sourceEnd = this.sourceStart;
		}
	}
	
	public final int sourceStart() {
		return sourceStart;
	}

	public final int sourceEnd() {
		return sourceEnd;
	}

	// TODO: Need to find way to change visibility to protected.
	public void setStart(int start) {
		this.sourceStart = start;
	}

	// TODO: Need to find way to change visibility to protected.
	public void setEnd(int end) {
		this.sourceEnd = end;
	}

	public abstract void traverse(ASTVisitor visitor) throws Exception;

	public void printNode(CorePrinter output) {
		output.println (this.getClass() + "(node doesn't support debug printing)\n" );
	}
	
	protected ISourceRange getSourceRange () {
		return new SourceRange(this.sourceStart(), this.sourceEnd() - this.sourceStart() + 1);
	}
	
	private static String simplifyClassName(String name) {
		int pos = name.lastIndexOf('.');
		return name.substring(pos + 1);
	}
	
	public String debugString () {
		return simplifyClassName(this.getClass().getName()) + "@" + this.getSourceRange().toString();
	}
	
	public String toString() {
		StringWriter writer = new StringWriter();
		CorePrinter printer = new CorePrinter(writer);
		this.printNode(printer);
		printer.flush();
		printer.close();
		return writer.getBuffer().toString();
	}
	
	/**
	 * Uses simplest visitor to get childs and returns collection of ASTNode objects
	 * @return
	 */
	public List getChilds () {
		final List result = new ArrayList();
		ASTVisitor visitor = new ASTVisitor() {

			public boolean visitGeneral(ASTNode node) throws Exception {
				if (node == ASTNode.this)
					return true;
				result.add(node);
				return false; //we needn't subchilds and more
			}
			
		};
		try {
			this.traverse(visitor);
		} catch (Exception e) {
			e.printStackTrace();
		}
		return result;
	}
	
}
