CodePatternMatcher.java

/*******************************************************************************
 * Copyright (c) 2025 Carsten Hammer.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     Carsten Hammer
 *******************************************************************************/
package org.sandbox.jdt.internal.corext.fix.helper.lib;

import org.eclipse.jdt.core.dom.ASTNode;
import org.eclipse.jdt.core.dom.MethodDeclaration;

/**
 * Code Pattern Matcher - AST-based pattern matching for code similarity
 * 
 * This class provides methods to match and compare AST structures
 * to identify similar code patterns.
 */
public class CodePatternMatcher {
	
	/**
	 * Match AST patterns between two nodes
	 * 
	 * @param node1 First AST node
	 * @param node2 Second AST node
	 * @return true if patterns match
	 */
	public static boolean matchPattern(ASTNode node1, ASTNode node2) {
		// TODO: Implement AST pattern matching
		// Compare:
		// - Node types
		// - Tree structure
		// - Normalized content
		// - Control flow patterns
		
		if (node1 == null || node2 == null) {
			return false;
		}
		
		// Basic check: same node type
		return node1.getNodeType() == node2.getNodeType();
	}
	
	/**
	 * Normalize AST for comparison
	 * 
	 * @param node The AST node to normalize
	 * @return Normalized representation
	 */
	public static String normalizeAST(ASTNode node) {
		// TODO: Implement AST normalization
		// Normalization steps:
		// 1. Replace variable names with placeholders
		// 2. Normalize literal values
		// 3. Standardize formatting
		// 4. Remove comments
		// 5. Generate canonical form
		
		if (node == null) {
			return "";
		}
		
		return node.toString();
	}
	
	/**
	 * Extract reusable pattern from method
	 * 
	 * @param method The method to analyze
	 * @return Pattern representation
	 */
	public static String extractPattern(MethodDeclaration method) {
		// TODO: Implement pattern extraction
		// Extract:
		// - Statement sequence
		// - Variable usage pattern
		// - Method call pattern
		// - Control flow structure
		
		if (method == null || method.getBody() == null) {
			return "";
		}
		
		return normalizeAST(method.getBody());
	}
	
	/**
	 * Tokenize AST node for comparison
	 * 
	 * @param node The AST node
	 * @return Token sequence
	 */
	public static String[] tokenize(ASTNode node) {
		// TODO: Implement tokenization
		// Generate sequence of tokens representing:
		// - Keywords
		// - Identifiers (normalized)
		// - Operators
		// - Literals (normalized)
		
		if (node == null) {
			return new String[0];
		}
		
		return new String[] { node.toString() };
	}
}