/*
 * JBoss, Home of Professional Open Source.
 * Copyright 2020, Red Hat, Inc., and individual contributors
 * as indicated by the @author tags. See the copyright.txt file in the
 * distribution for a full listing of individual contributors.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */

package org.wildfly.clustering.marshalling.protostream;

import java.io.IOException;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Proxy;
import java.util.BitSet;
import java.util.IdentityHashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;

import org.infinispan.protostream.descriptors.WireType;
import org.wildfly.security.manager.WildFlySecurityManager;

/**
 * A set of fields used by {@link AnyMarshaller}.
 * @author Paul Ferraro
 */
public enum AnyField implements Field<Object> {
    ANY(Scalar.ANY), // For re-use by other fields
    REFERENCE(Scalar.REFERENCE),
    BOOLEAN(Scalar.BOOLEAN),
    BYTE(Scalar.BYTE),
    SHORT(Scalar.SHORT),
    INTEGER(Scalar.INTEGER),
    LONG(Scalar.LONG),
    FLOAT(Scalar.FLOAT),
    DOUBLE(Scalar.DOUBLE),
    CHARACTER(Scalar.CHARACTER),
    STRING(Scalar.STRING),
    IDENTIFIED_OBJECT(new TypedObjectMarshaller(ScalarClass.ID)),
    IDENTIFIED_ENUM(new TypedEnumMarshaller<>(ScalarClass.ID)),
    IDENTIFIED_ARRAY(new TypedArrayMarshaller(ScalarClass.ID)),
    FIELD_ARRAY(new TypedArrayMarshaller(ScalarClass.FIELD)),
    // Prioritize the fields above:  https://developers.google.com/protocol-buffers/docs/proto#assigning_field_numbers
    NAMED_OBJECT(new TypedObjectMarshaller(ScalarClass.NAME)),
    NAMED_ENUM(new TypedEnumMarshaller<>(ScalarClass.NAME)),
    NAMED_ARRAY(new TypedArrayMarshaller(ScalarClass.NAME)),
    BOOLEAN_ARRAY(new FieldMarshaller<boolean[]>() {
        // Optimize using a BitSet, rather than a packed array of booleans
        @Override
        public boolean[] readFrom(ProtoStreamReader reader) throws IOException {
            byte[] bytes = Scalar.BYTE_ARRAY.cast(byte[].class).readFrom(reader);
            int length = bytes.length;
            while (!reader.isAtEnd()) {
                int tag = reader.readTag();
                int index = WireType.getTagFieldNumber(tag);
                if (index == INTEGER.getIndex()) {
                    // Adjust length of boolean[]
                    length = ((bytes.length - 1) * Byte.SIZE) + reader.readUInt32();
                } else {
                    reader.skipField(tag);
                }
            }
            BitSet set = BitSet.valueOf(bytes);
            boolean[] values = new boolean[length];
            for (int i = 0; i < length; ++i) {
                values[i] = set.get(i);
            }
            return values;
        }

        @Override
        public void writeTo(ProtoStreamWriter writer, boolean[] values) throws IOException {
            int length = values.length;
            // Pack boolean values into BitSet
            BitSet set = new BitSet(length);
            for (int i = 0; i < length; ++i) {
                set.set(i, values[i]);
            }
            byte[] bytes = set.toByteArray();
            Scalar.BYTE_ARRAY.cast(byte[].class).writeTo(writer, bytes);
            // boolean[] length might be shorter than the BitSet, if so, write the difference
            int remainder = length % Byte.SIZE;
            if (remainder > 0) {
                writer.writeUInt32(INTEGER.getIndex(), remainder);
            }
        }

        @Override
        public Class<? extends boolean[]> getJavaClass() {
            return boolean[].class;
        }

        @Override
        public WireType getWireType() {
            return Scalar.BYTE_ARRAY.getWireType();
        }
    }),
    BYTE_ARRAY(Scalar.BYTE_ARRAY),
    SHORT_ARRAY(new PackedArrayMarshaller<>(Short.TYPE, Scalar.SHORT.cast(Short.class))),
    INTEGER_ARRAY(new PackedArrayMarshaller<>(Integer.TYPE, Scalar.INTEGER.cast(Integer.class))),
    LONG_ARRAY(new PackedArrayMarshaller<>(Long.TYPE, Scalar.LONG.cast(Long.class))),
    FLOAT_ARRAY(new PackedArrayMarshaller<>(Float.TYPE, Scalar.FLOAT.cast(Float.class))),
    DOUBLE_ARRAY(new PackedArrayMarshaller<>(Double.TYPE, Scalar.DOUBLE.cast(Double.class))),
    CHAR_ARRAY(new PackedArrayMarshaller<>(Character.TYPE, Scalar.CHARACTER.cast(Character.class))),
    ANY_ARRAY(new TypedArrayMarshaller(ScalarClass.ANY)),
    PROXY(new FieldMarshaller<Object>() {
        @Override
        public Object readFrom(ProtoStreamReader reader) throws IOException {
            InvocationHandler handler = (InvocationHandler) Scalar.ANY.readFrom(reader);
            List<Class<?>> interfaces = new LinkedList<>();
            while (!reader.isAtEnd()) {
                int tag = reader.readTag();
                int index = WireType.getTagFieldNumber(tag);
                if (index == ANY.getIndex()) {
                    interfaces.add(ScalarClass.ANY.readFrom(reader));
                } else {
                    reader.skipField(tag);
                }
            }
            return Proxy.newProxyInstance(WildFlySecurityManager.getClassLoaderPrivileged(handler.getClass()), interfaces.toArray(new Class<?>[0]), handler);
        }

        @Override
        public void writeTo(ProtoStreamWriter writer, Object proxy) throws IOException {
            Scalar.ANY.writeTo(writer, Proxy.getInvocationHandler(proxy));

            for (Class<?> interfaceClass : proxy.getClass().getInterfaces()) {
                writer.writeTag(ANY.getIndex(), ScalarClass.ANY.getWireType());
                ScalarClass.ANY.writeTo(writer, interfaceClass);
            }
        }

        @Override
        public Class<? extends Object> getJavaClass() {
            return Object.class;
        }

        @Override
        public WireType getWireType() {
            return WireType.LENGTH_DELIMITED;
        }
    }),
    ;
    private final FieldMarshaller<Object> marshaller;

    AnyField(ScalarMarshaller<?> marshaller) {
        this(new ScalarFieldMarshaller<>(marshaller));
    }

    @SuppressWarnings("unchecked")
    AnyField(FieldMarshaller<?> marshaller) {
        this.marshaller = (FieldMarshaller<Object>) marshaller;
    }

    @Override
    public int getIndex() {
        return this.ordinal() + 1;
    }

    @Override
    public FieldMarshaller<Object> getMarshaller() {
        return this.marshaller;
    }

    private static final AnyField[] VALUES = AnyField.values();

    static AnyField fromIndex(int index) {
        return (index > 0) && (index <= VALUES.length) ? VALUES[index - 1] : null;
    }

    private static final Map<Class<?>, AnyField> FIELDS = new IdentityHashMap<>();
    static {
        for (AnyField field : VALUES) {
            Class<?> fieldClass = field.getMarshaller().getJavaClass();
            if ((fieldClass != Object.class) && (fieldClass != Enum.class) && fieldClass != Class.class) {
                FIELDS.put(fieldClass, field);
            }
        }
    }

    static AnyField fromJavaType(Class<?> targetClass) {
        return FIELDS.get(targetClass);
    }
}