/*

 * Copyright (c) 1998, 2017, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package com.sun.tools.jdi;

import java.util.ArrayList;

import java.util.List;

import com.sun.jdi.AbsentInformationException;

import com.sun.jdi.ArrayReference;

import com.sun.jdi.ArrayType;

import com.sun.jdi.ClassNotLoadedException;

import com.sun.jdi.InterfaceType;

import com.sun.jdi.InvalidTypeException;

import com.sun.jdi.Location;

import com.sun.jdi.Method;

import com.sun.jdi.Type;

import com.sun.jdi.Value;

import com.sun.jdi.VirtualMachine;

public abstract class MethodImpl extends TypeComponentImpl

                                 implements Method

{

    private JNITypeParser signatureParser;

    abstract int argSlotCount() throws AbsentInformationException;

    abstract List<Location> allLineLocations(SDE.Stratum stratum,

                                             String sourceName)

                            throws AbsentInformationException;

    abstract List<Location> locationsOfLine(SDE.Stratum stratum,

                                            String sourceName,

                                            int lineNumber)

                            throws AbsentInformationException;

    MethodImpl(VirtualMachine vm, ReferenceTypeImpl declaringType,

               long ref, String name, String signature,

               String genericSignature, int modifiers) {

        super(vm, declaringType, ref, name, signature,

              genericSignature, modifiers);

        signatureParser = new JNITypeParser(signature);

    }

    static MethodImpl createMethodImpl(VirtualMachine vm,

                                       ReferenceTypeImpl declaringType,

                                       long ref,

                                       String name,

                                       String signature,

                                       String genericSignature,

                                       int modifiers) {

        if ((modifiers & (VMModifiers.NATIVE | VMModifiers.ABSTRACT)) != 0) {

            return new NonConcreteMethodImpl(vm, declaringType, ref,

                                             name, signature,

                                             genericSignature,

                                             modifiers);

        } else {

            return new ConcreteMethodImpl(vm, declaringType, ref,

                                          name, signature,

                                          genericSignature,

                                          modifiers);

        }

    }

    public boolean equals(Object obj) {

        if ((obj != null) && (obj instanceof MethodImpl)) {

            MethodImpl other = (MethodImpl)obj;

            return (declaringType().equals(other.declaringType())) &&

                   (ref() == other.ref()) &&

                   super.equals(obj);

        } else {

            return false;

        }

    }

    public int hashCode() {

        return (int)ref();

    }

    public final List<Location> allLineLocations()

                                throws AbsentInformationException {

        return allLineLocations(vm.getDefaultStratum(), null);

    }

    public List<Location> allLineLocations(String stratumID,

                                           String sourceName)

                          throws AbsentInformationException {

        return allLineLocations(declaringType.stratum(stratumID), sourceName);

    }

    public final List<Location> locationsOfLine(int lineNumber)

                                throws AbsentInformationException {

        return locationsOfLine(vm.getDefaultStratum(),

                               null, lineNumber);

    }

    public List<Location> locationsOfLine(String stratumID,

                                          String sourceName,

                                          int lineNumber)

                          throws AbsentInformationException {

        return locationsOfLine(declaringType.stratum(stratumID),

                               sourceName, lineNumber);

    }

    LineInfo codeIndexToLineInfo(SDE.Stratum stratum,

                                 long codeIndex) {

        if (stratum.isJava()) {

            return new BaseLineInfo(-1, declaringType);

        } else {

            return new StratumLineInfo(stratum.id(), -1, null, null);

        }

    }

    /**

     * @return a text representation of the declared return type

     * of this method.

     */

    public String returnTypeName() {

        return signatureParser.typeName();

    }

    private String returnSignature() {

        return signatureParser.signature();

    }

    public Type returnType() throws ClassNotLoadedException {

        return findType(returnSignature());

    }

    public Type findType(String signature) throws ClassNotLoadedException {

        ReferenceTypeImpl enclosing = (ReferenceTypeImpl)declaringType();

        return enclosing.findType(signature);

    }

    public List<String> argumentTypeNames() {

        return signatureParser.argumentTypeNames();

    }

    public List<String> argumentSignatures() {

        return signatureParser.argumentSignatures();

    }

    Type argumentType(int index) throws ClassNotLoadedException {

        ReferenceTypeImpl enclosing = (ReferenceTypeImpl)declaringType();

        String signature = argumentSignatures().get(index);

        return enclosing.findType(signature);

    }

    public List<Type> argumentTypes() throws ClassNotLoadedException {

        int size = argumentSignatures().size();

        List<Type> types = new ArrayList<>(size);

        for (int i = 0; i < size; i++) {

            Type type = argumentType(i);

            types.add(type);

        }

        return types;

    }

    public int compareTo(Method method) {

        ReferenceTypeImpl declaringType = (ReferenceTypeImpl)declaringType();

        int rc = declaringType.compareTo(method.declaringType());

        if (rc == 0) {

            rc = declaringType.indexOf(this) - declaringType.indexOf(method);

        }

        return rc;

    }

    public boolean isAbstract() {

        return isModifierSet(VMModifiers.ABSTRACT);

    }

    public boolean isDefault() {

        return !isModifierSet(VMModifiers.ABSTRACT) &&

               !isModifierSet(VMModifiers.STATIC) &&

               !isModifierSet(VMModifiers.PRIVATE) &&

               declaringType() instanceof InterfaceType;

    }

    public boolean isSynchronized() {

        return isModifierSet(VMModifiers.SYNCHRONIZED);

    }

    public boolean isNative() {

        return isModifierSet(VMModifiers.NATIVE);

    }

    public boolean isVarArgs() {

        return isModifierSet(VMModifiers.VARARGS);

    }

    public boolean isBridge() {

        return isModifierSet(VMModifiers.BRIDGE);

    }

    public boolean isConstructor() {

        return name().equals("<init>");

    }

    public boolean isStaticInitializer() {

        return name().equals("<clinit>");

    }

    public boolean isObsolete() {

        try {

            return JDWP.Method.IsObsolete.process(vm,

                                    declaringType, ref).isObsolete;

        } catch (JDWPException exc) {

            throw exc.toJDIException();

        }

    }

    /*

     * A container class for the return value to allow

     * proper type-checking.

     */

    class ReturnContainer implements ValueContainer {

        ReturnContainer() {

        }

        public Type type() throws ClassNotLoadedException {

            return returnType();

        }

        public String typeName(){

            return returnTypeName();

        }

        public String signature() {

            return returnSignature(); //type().signature();

        }

        public Type findType(String signature) throws ClassNotLoadedException {

            return MethodImpl.this.findType(signature);

        }

    }

    ReturnContainer retValContainer = null;

    ReturnContainer getReturnValueContainer() {

        if (retValContainer == null) {

            retValContainer = new ReturnContainer();

        }

        return retValContainer;

    }

    /*

     * A container class for the argument to allow

     * proper type-checking.

     */

    class ArgumentContainer implements ValueContainer {

        int index;

        ArgumentContainer(int index) {

            this.index = index;

        }

        public Type type() throws ClassNotLoadedException {

            return argumentType(index);

        }

        public String typeName(){

            return argumentTypeNames().get(index);

        }

        public String signature() {

            return argumentSignatures().get(index);

        }

        public Type findType(String signature) throws ClassNotLoadedException {

            return MethodImpl.this.findType(signature);

        }

    }

    /*

     * This is a var args method.  Thus, its last param is an

     * array. If the method has n params, then:

     * 1.  If there are n args and the last is the same type as the type of

     *     the last param, do nothing.  IE, a String[]

     *     can be passed to a String...

     * 2.  If there are >= n arguments and for each arg whose number is >= n,

     *     the arg type is 'compatible' with the component type of

     *     the last param, then do

     *     - create an array of the type of the last param

     *     - put the n, ... args into this array.

     *       We might have to do conversions here.

     *     - put this array into arguments(n)

     *     - delete arguments(n+1), ...

     * NOTE that this might modify the input list.

     */

    void handleVarArgs(List<Value> arguments)

        throws ClassNotLoadedException, InvalidTypeException {

        List<Type> paramTypes = this.argumentTypes();

        ArrayType lastParamType = (ArrayType)paramTypes.get(paramTypes.size() - 1);

        int argCount = arguments.size();

        int paramCount = paramTypes.size();

        if (argCount < paramCount - 1) {

            // Error; will be caught later.

            return;

        }

        if (argCount == paramCount - 1) {

            // It is ok to pass 0 args to the var arg.

            // We have to gen a 0 length array.

            ArrayReference argArray = lastParamType.newInstance(0);

            arguments.add(argArray);

            return;

        }

        Value nthArgValue = arguments.get(paramCount - 1);

        if (nthArgValue == null && argCount == paramCount) {

            // We have one varargs parameter and it is null

            // so we don't have to do anything.

            return;

        }

        // If the first varargs parameter is null, then don't

        // access its type since it can't be an array.

        Type nthArgType = (nthArgValue == null) ? null : nthArgValue.type();

        if (nthArgType instanceof ArrayTypeImpl) {

            if (argCount == paramCount &&

                ((ArrayTypeImpl)nthArgType).isAssignableTo(lastParamType)) {

                /*

                 * This is case 1.  A compatible array is being passed to the

                 * var args array param.  We don't have to do anything.

                 */

                return;

            }

        }

        /*

         * Case 2.  We have to verify that the n, n+1, ... args are compatible

         * with componentType, and do conversions if necessary and create

         * an array of componentType to hold these possibly converted values.

         */

        int count = argCount - paramCount + 1;

        ArrayReference argArray = lastParamType.newInstance(count);

        /*

         * This will copy arguments(paramCount - 1) ... to argArray(0) ...

         * doing whatever conversions are needed!  It will throw an

         * exception if an incompatible arg is encountered

         */

        argArray.setValues(0, arguments, paramCount - 1, count);

        arguments.set(paramCount - 1, argArray);

        /*

         * Remove the excess args

         */

        for (int ii = paramCount; ii < argCount; ii++) {

            arguments.remove(paramCount);

        }

        return;

    }

    /*

     * The output list will be different than the input list.

     */

    List<Value> validateAndPrepareArgumentsForInvoke(List<? extends Value> origArguments)

                         throws ClassNotLoadedException, InvalidTypeException {

        List<Value> arguments = new ArrayList<>(origArguments);

        if (isVarArgs()) {

            handleVarArgs(arguments);

        }

        int argSize = arguments.size();

        JNITypeParser parser = new JNITypeParser(signature());

        List<String> signatures = parser.argumentSignatures();

        if (signatures.size() != argSize) {

            throw new IllegalArgumentException("Invalid argument count: expected " +

                                               signatures.size() + ", received " +

                                               arguments.size());

        }

        for (int i = 0; i < argSize; i++) {

            Value value = arguments.get(i);

            value = ValueImpl.prepareForAssignment(value,

                                                   new ArgumentContainer(i));

            arguments.set(i, value);

        }

        return arguments;

    }

    public String toString() {

        StringBuilder sb = new StringBuilder();

        sb.append(declaringType().name());

        sb.append(".");

        sb.append(name());

        sb.append("(");

        boolean first = true;

        for (String name : argumentTypeNames()) {

            if (!first) {

                sb.append(", ");

            }

            sb.append(name);

            first = false;

        }

        sb.append(")");

        return sb.toString();

    }

}