/*
 * Copyright 2003,2004 The Apache Software Foundation
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package net.sf.cglib.reflect;

import net.sf.cglib.core.*;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.security.ProtectionDomain;
import org.objectweb.asm.ClassVisitor;
import org.objectweb.asm.Type;

abstract public class FastClass
{
    private Class type;

    protected FastClass() {
        throw new Error("Using the FastClass empty constructor--please report to the cglib-devel mailing list");
    }

    protected FastClass(Class type) {
        this.type = type;
    }

    public static FastClass create(Class type) {
    
        return create(type.getClassLoader(),type);
        
    }
    public static FastClass create(ClassLoader loader, Class type) {
        Generator gen = new Generator();
        gen.setType(type);
        gen.setClassLoader(loader);
        return gen.create();
    }

    public static class Generator extends AbstractClassGenerator
    {
        private static final Source SOURCE = new Source(FastClass.class.getName());
        private Class type;
        
        public Generator() {
            super(SOURCE);
        }

        public void setType(Class type) {
            this.type = type;
        }
        
        public FastClass create() {
            setNamePrefix(type.getName());
            return (FastClass)super.create(type.getName());
        }

        protected ClassLoader getDefaultClassLoader() {
            return type.getClassLoader();
        }

        protected ProtectionDomain getProtectionDomain() {
        	return ReflectUtils.getProtectionDomain(type);
        }

        public void generateClass(ClassVisitor v) throws Exception {
            new FastClassEmitter(v, getClassName(), type);
        }

        protected Object firstInstance(Class type) {
            return ReflectUtils.newInstance(type,
                                            new Class[]{ Class.class },
                                            new Object[]{ this.type });
        }

        protected Object nextInstance(Object instance) {
            return instance;
        }
    }
    
    public Object invoke(String name, Class[] parameterTypes, Object obj, Object[] args) throws InvocationTargetException {
        return invoke(getIndex(name, parameterTypes), obj, args);
    }

    public Object newInstance() throws InvocationTargetException {
        return newInstance(getIndex(Constants.EMPTY_CLASS_ARRAY), null);
    }

    public Object newInstance(Class[] parameterTypes, Object[] args) throws InvocationTargetException {
        return newInstance(getIndex(parameterTypes), args);
    }
    
    public FastMethod getMethod(Method method) {
        return new FastMethod(this, method);
    }

    public FastConstructor getConstructor(Constructor constructor) {
        return new FastConstructor(this, constructor);
    }

    public FastMethod getMethod(String name, Class[] parameterTypes) {
        try {
            return getMethod(type.getMethod(name, parameterTypes));
        } catch (NoSuchMethodException e) {
            throw new NoSuchMethodError(e.getMessage());
        }
    }

    public FastConstructor getConstructor(Class[] parameterTypes) {
        try {
            return getConstructor(type.getConstructor(parameterTypes));
        } catch (NoSuchMethodException e) {
            throw new NoSuchMethodError(e.getMessage());
        }
    }

    public String getName() {
        return type.getName();
    }

    public Class getJavaClass() {
        return type;
    }

    public String toString() {
        return type.toString();
    }

    public int hashCode() {
        return type.hashCode();
    }

    public boolean equals(Object o) {
        if (o == null || !(o instanceof FastClass)) {
            return false;
        }
        return type.equals(((FastClass)o).type);
    }

    
Return the index of the matching method. The index may be used
later to invoke the method with less overhead. If more than one
method matches (i.e. they differ by return type only), one is
chosen arbitrarily.
Params:
name – the method name
parameterTypes – the parameter array
See Also:
invoke(int, Object, Object[])
Returns:
the index, or -1 if none is found./**
     * Return the index of the matching method. The index may be used
     * later to invoke the method with less overhead. If more than one
     * method matches (i.e. they differ by return type only), one is
     * chosen arbitrarily.
     * @see #invoke(int, Object, Object[])
     * @param name the method name
     * @param parameterTypes the parameter array
     * @return the index, or <code>-1</code> if none is found.
     */
    abstract public int getIndex(String name, Class[] parameterTypes);

    
Return the index of the matching constructor. The index may be used
later to create a new instance with less overhead.
Params:
parameterTypes – the parameter array
See Also:
newInstance(int, Object[])
Returns:
the constructor index, or -1 if none is found./**
     * Return the index of the matching constructor. The index may be used
     * later to create a new instance with less overhead.
     * @see #newInstance(int, Object[])
     * @param parameterTypes the parameter array
     * @return the constructor index, or <code>-1</code> if none is found.
     */
    abstract public int getIndex(Class[] parameterTypes);

    
Invoke the method with the specified index.
Params:
index – the method index
obj – the object the underlying method is invoked from
args – the arguments used for the method call
Throws:
InvocationTargetException – if the underlying method throws an exception
See Also:
getIndex(name, Class[])/**
     * Invoke the method with the specified index.
     * @see getIndex(name, Class[])
     * @param index the method index
     * @param obj the object the underlying method is invoked from
     * @param args the arguments used for the method call
     * @throws java.lang.reflect.InvocationTargetException if the underlying method throws an exception
     */
    abstract public Object invoke(int index, Object obj, Object[] args) throws InvocationTargetException;

    
Create a new instance using the specified constructor index and arguments.
Params:
index – the constructor index
args – the arguments passed to the constructor
Throws:
InvocationTargetException – if the constructor throws an exception
See Also:
getIndex(Class[])/**
     * Create a new instance using the specified constructor index and arguments.
     * @see getIndex(Class[])
     * @param index the constructor index
     * @param args the arguments passed to the constructor
     * @throws java.lang.reflect.InvocationTargetException if the constructor throws an exception
     */
    abstract public Object newInstance(int index, Object[] args) throws InvocationTargetException;

    abstract public int getIndex(Signature sig);

    
Returns the maximum method index for this class.
/**
     * Returns the maximum method index for this class.
     */
    abstract public int getMaxIndex();

    protected static String getSignatureWithoutReturnType(String name, Class[] parameterTypes) {
        StringBuffer sb = new StringBuffer();
        sb.append(name);
        sb.append('(');
        for (int i = 0; i < parameterTypes.length; i++) {
            sb.append(Type.getDescriptor(parameterTypes[i]));
        }
        sb.append(')');
        return sb.toString();
    }
}