Copyright (c) 2000, 2014 IBM Corporation and others.
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:
    IBM Corporation - initial API and implementation
/*******************************************************************************
 * Copyright (c) 2000, 2014 IBM Corporation and others.
 *
 * 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:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.jdt.internal.core.search.matching;

import java.io.IOException;

import org.eclipse.jdt.core.*;
import org.eclipse.jdt.core.compiler.CharOperation;
import org.eclipse.jdt.core.search.IJavaSearchConstants;
import org.eclipse.jdt.core.search.SearchPattern;
import org.eclipse.jdt.internal.core.index.*;
import org.eclipse.jdt.internal.core.util.Util;

public class MethodPattern extends JavaSearchPattern {

protected boolean findDeclarations = true;
protected boolean findReferences = true;

public char[] selector;

public char[] declaringQualification;
public char[] declaringSimpleName;
public char[] declaringPackageName; //set only when focus is not null

public char[] returnQualification;
public char[] returnSimpleName;

public char[][] parameterQualifications;
public char[][] parameterSimpleNames;
public int parameterCount;
public boolean varargs = false;

// extra reference info
protected IType declaringType;

// Signatures and arguments for generic search
char[][] returnTypeSignatures;
char[][][] parametersTypeSignatures;
char[][][][] parametersTypeArguments;
boolean methodParameters = false;
char[][] methodArguments;

protected static char[][] REF_CATEGORIES = { METHOD_REF };
protected static char[][] REF_AND_DECL_CATEGORIES = { METHOD_REF, METHOD_DECL };
protected static char[][] DECL_CATEGORIES = { METHOD_DECL };

public final static int FINE_GRAIN_MASK =
	IJavaSearchConstants.SUPER_REFERENCE |
	IJavaSearchConstants.QUALIFIED_REFERENCE |
	IJavaSearchConstants.THIS_REFERENCE |
	IJavaSearchConstants.IMPLICIT_THIS_REFERENCE |
	IJavaSearchConstants.METHOD_REFERENCE_EXPRESSION;

Method entries are encoded as selector '/' Arity:
e.g. 'foo/0'
/**
 * Method entries are encoded as selector '/' Arity:
 * e.g. 'foo/0'
 */
public static char[] createIndexKey(char[] selector, int argCount) {
	char[] countChars = argCount < 10
		? COUNTS[argCount]
		: ("/" + String.valueOf(argCount)).toCharArray(); //$NON-NLS-1$
	return CharOperation.concat(selector, countChars);
}

MethodPattern(int matchRule) {
	super(METHOD_PATTERN, matchRule);
}
public MethodPattern(
	char[] selector,
	char[] declaringQualification,
	char[] declaringSimpleName,
	char[] returnQualification,
	char[] returnSimpleName,
	char[][] parameterQualifications,
	char[][] parameterSimpleNames,
	IType declaringType,
	int limitTo,
	int matchRule) {

	this(matchRule);

	this.fineGrain = limitTo & FINE_GRAIN_MASK;
    if (this.fineGrain == 0) {
		switch (limitTo & 0xF) {
			case IJavaSearchConstants.DECLARATIONS :
				this.findReferences = false;
				break;
			case IJavaSearchConstants.REFERENCES :
				this.findDeclarations = false;
				break;
			case IJavaSearchConstants.ALL_OCCURRENCES :
				break;
		}
    } else {
		this.findDeclarations = false;
    }

	this.selector = (this.isCaseSensitive || this.isCamelCase) ? selector : CharOperation.toLowerCase(selector);
	this.declaringQualification = this.isCaseSensitive ? declaringQualification : CharOperation.toLowerCase(declaringQualification);
	this.declaringSimpleName = this.isCaseSensitive ? declaringSimpleName : CharOperation.toLowerCase(declaringSimpleName);
	this.returnQualification = this.isCaseSensitive ? returnQualification : CharOperation.toLowerCase(returnQualification);
	this.returnSimpleName = this.isCaseSensitive ? returnSimpleName : CharOperation.toLowerCase(returnSimpleName);
	if (parameterSimpleNames != null) {
		this.parameterCount = parameterSimpleNames.length;
		this.parameterQualifications = new char[this.parameterCount][];
		this.parameterSimpleNames = new char[this.parameterCount][];
		for (int i = 0; i < this.parameterCount; i++) {
			this.parameterQualifications[i] = this.isCaseSensitive ? parameterQualifications[i] : CharOperation.toLowerCase(parameterQualifications[i]);
			this.parameterSimpleNames[i] = this.isCaseSensitive ? parameterSimpleNames[i] : CharOperation.toLowerCase(parameterSimpleNames[i]);
		}
	} else {
		this.parameterCount = -1;
	}
	this.declaringType = declaringType;
	if (this.declaringType !=  null) {
		this.declaringPackageName = this.declaringType.getPackageFragment().getElementName().toCharArray();
	}
	this.mustResolve = mustResolve();
}
/*
 * Instanciate a method pattern with signatures for generics search
 */
public MethodPattern(
	char[] selector,
	char[] declaringQualification,
	char[] declaringSimpleName,
	char[] returnQualification,
	char[] returnSimpleName,
	String returnSignature,
	char[][] parameterQualifications,
	char[][] parameterSimpleNames,
	String[] parameterSignatures,
	IMethod method,
	int limitTo,
	int matchRule) {

	this(selector,
		declaringQualification,
		declaringSimpleName,
		returnQualification,
		returnSimpleName,
		parameterQualifications,
		parameterSimpleNames,
		method.getDeclaringType(),
		limitTo,
		matchRule);

	// Set flags
	try {
		this.varargs = (method.getFlags() & Flags.AccVarargs) != 0;
	} catch (JavaModelException e) {
		// do nothing
	}

	// Get unique key for parameterized constructors
	String genericDeclaringTypeSignature = null;
	if (method.isResolved()) {
		String key = method.getKey();
		BindingKey bindingKey = new BindingKey(key);
		if (bindingKey.isParameterizedType()) {
			genericDeclaringTypeSignature = Util.getDeclaringTypeSignature(key);
			// Store type signature and arguments for declaring type
			if (genericDeclaringTypeSignature != null) {
					this.typeSignatures = Util.splitTypeLevelsSignature(genericDeclaringTypeSignature);
					setTypeArguments(Util.getAllTypeArguments(this.typeSignatures));
			}
		}
	} else {
		this.methodParameters = true;
		storeTypeSignaturesAndArguments(this.declaringType);
	}

	// Store type signatures and arguments for return type
	if (returnSignature != null) {
		this.returnTypeSignatures = Util.splitTypeLevelsSignature(returnSignature);
	}

	// Store type signatures and arguments for method parameters type
	if (parameterSignatures != null) {
		int length = parameterSignatures.length;
		if (length > 0) {
			this.parametersTypeSignatures = new char[length][][];
			this.parametersTypeArguments = new char[length][][][];
			for (int i=0; i<length; i++) {
				this.parametersTypeSignatures[i] = Util.splitTypeLevelsSignature(parameterSignatures[i]);
				this.parametersTypeArguments[i] = Util.getAllTypeArguments(this.parametersTypeSignatures[i]);
			}
		}
	}

	// Store type signatures and arguments for method
	this.methodArguments = extractMethodArguments(method);
	if (hasMethodArguments())  this.mustResolve = true;
}
/*
 * Instanciate a method pattern with signatures for generics search
 */
public MethodPattern(
	char[] selector,
	char[] declaringQualification,
	char[] declaringSimpleName,
	String declaringSignature,
	char[] returnQualification,
	char[] returnSimpleName,
	String returnSignature,
	char[][] parameterQualifications,
	char[][] parameterSimpleNames,
	String[] parameterSignatures,
	char[][] arguments,
	int limitTo,
	int matchRule) {

	this(selector,
		declaringQualification,
		declaringSimpleName,
		returnQualification,
		returnSimpleName,
		parameterQualifications,
		parameterSimpleNames,
		null,
		limitTo,
		matchRule);

	// Store type signature and arguments for declaring type
	if (declaringSignature != null) {
		this.typeSignatures = Util.splitTypeLevelsSignature(declaringSignature);
		setTypeArguments(Util.getAllTypeArguments(this.typeSignatures));
	}

	// Store type signatures and arguments for return type
	if (returnSignature != null) {
		this.returnTypeSignatures = Util.splitTypeLevelsSignature(returnSignature);
	}

	// Store type signatures and arguments for method parameters type
	if (parameterSignatures != null) {
		int length = parameterSignatures.length;
		if (length > 0) {
			this.parametersTypeSignatures = new char[length][][];
			this.parametersTypeArguments = new char[length][][][];
			for (int i=0; i<length; i++) {
				this.parametersTypeSignatures[i] = Util.splitTypeLevelsSignature(parameterSignatures[i]);
				this.parametersTypeArguments[i] = Util.getAllTypeArguments(this.parametersTypeSignatures[i]);
			}
		}
	}

	// Store type signatures and arguments for method
	this.methodArguments = arguments;
	if (hasMethodArguments())  this.mustResolve = true;
}
@Override
public void decodeIndexKey(char[] key) {
	int last = key.length - 1;
	this.parameterCount = 0;
	this.selector = null;
	int power = 1;
	for (int i=last; i>=0; i--) {
		if (key[i] == SEPARATOR) {
			System.arraycopy(key, 0, this.selector = new char[i], 0, i);
			break;
		}
		if (i == last) {
			this.parameterCount = key[i] - '0';
		} else {
			power *= 10;
			this.parameterCount += power * (key[i] - '0');
		}
	}
}
@Override
public SearchPattern getBlankPattern() {
	return new MethodPattern(R_EXACT_MATCH | R_CASE_SENSITIVE);
}
@Override
public char[][] getIndexCategories() {
	if (this.findReferences)
		return this.findDeclarations ? REF_AND_DECL_CATEGORIES : REF_CATEGORIES;
	if (this.findDeclarations)
		return DECL_CATEGORIES;
	return CharOperation.NO_CHAR_CHAR;
}
boolean hasMethodArguments() {
	return this.methodArguments != null && this.methodArguments.length > 0;
}
boolean hasMethodParameters() {
	return this.methodParameters;
}
@Override
public boolean isPolymorphicSearch() {
	return this.findReferences;
}
@Override
public boolean matchesDecodedKey(SearchPattern decodedPattern) {
	MethodPattern pattern = (MethodPattern) decodedPattern;

	return (this.parameterCount == pattern.parameterCount || this.parameterCount == -1 || this.varargs)
		&& matchesName(this.selector, pattern.selector);
}
Returns whether a method declaration or message send must be resolved to
find out if this method pattern matches it.
/**
 * Returns whether a method declaration or message send must be resolved to
 * find out if this method pattern matches it.
 */
protected boolean mustResolve() {
	// declaring type
	// If declaring type is specified - even with simple name - always resolves
	if (this.declaringSimpleName != null || this.declaringQualification != null) return true;

	// return type
	// If return type is specified - even with simple name - always resolves
	if (this.returnSimpleName != null || this.returnQualification != null) return true;

	// parameter types
	if (this.parameterSimpleNames != null)
		for (int i = 0, max = this.parameterSimpleNames.length; i < max; i++)
			if (this.parameterQualifications[i] != null) return true;
	return false;
}
@Override
public EntryResult[] queryIn(Index index) throws IOException {
	char[] key = this.selector; // can be null
	int matchRule = getMatchRule();

	switch(getMatchMode()) {
		case R_EXACT_MATCH :
			if (this.selector != null && this.parameterCount >= 0 && !this.varargs)
				key = createIndexKey(this.selector, this.parameterCount);
			else { // do a prefix query with the selector
				matchRule &= ~R_EXACT_MATCH;
				matchRule |= R_PREFIX_MATCH;
			}
			break;
		case R_PREFIX_MATCH :
			// do a prefix query with the selector
			break;
		case R_PATTERN_MATCH :
			if (this.parameterCount >= 0 && !this.varargs)
				key = createIndexKey(this.selector == null ? ONE_STAR : this.selector, this.parameterCount);
			else if (this.selector != null && this.selector[this.selector.length - 1] != '*')
				key = CharOperation.concat(this.selector, ONE_STAR, SEPARATOR);
			// else do a pattern query with just the selector
			break;
		case R_REGEXP_MATCH :
			// TODO (frederic) implement regular expression match
			break;
		case R_CAMELCASE_MATCH:
		case R_CAMELCASE_SAME_PART_COUNT_MATCH:
			// do a prefix query with the selector
			break;
	}

	return index.query(getIndexCategories(), key, matchRule); // match rule is irrelevant when the key is null
}
@Override
protected StringBuffer print(StringBuffer output) {
	if (this.findDeclarations) {
		output.append(this.findReferences
			? "MethodCombinedPattern: " //$NON-NLS-1$
			: "MethodDeclarationPattern: "); //$NON-NLS-1$
	} else {
		output.append("MethodReferencePattern: "); //$NON-NLS-1$
	}
	if (this.declaringQualification != null)
		output.append(this.declaringQualification).append('.');
	if (this.declaringSimpleName != null)
		output.append(this.declaringSimpleName).append('.');
	else if (this.declaringQualification != null)
		output.append("*."); //$NON-NLS-1$

	if (this.selector != null)
		output.append(this.selector);
	else
		output.append("*"); //$NON-NLS-1$
	output.append('(');
	if (this.parameterSimpleNames == null) {
		output.append("..."); //$NON-NLS-1$
	} else {
		for (int i = 0, max = this.parameterSimpleNames.length; i < max; i++) {
			if (i > 0) output.append(", "); //$NON-NLS-1$
			if (this.parameterQualifications[i] != null) output.append(this.parameterQualifications[i]).append('.');
			if (this.parameterSimpleNames[i] == null) output.append('*'); else output.append(this.parameterSimpleNames[i]);
		}
	}
	output.append(')');
	if (this.returnQualification != null)
		output.append(" --> ").append(this.returnQualification).append('.'); //$NON-NLS-1$
	else if (this.returnSimpleName != null)
		output.append(" --> "); //$NON-NLS-1$
	if (this.returnSimpleName != null)
		output.append(this.returnSimpleName);
	else if (this.returnQualification != null)
		output.append("*"); //$NON-NLS-1$
	return super.print(output);
}
}