/*
 * JBoss, Home of Professional Open Source.
 * Copyright 2011, 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.jboss.as.controller;


import java.util.List;
import java.util.Locale;
import java.util.ResourceBundle;

import javax.xml.stream.Location;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.XMLStreamWriter;

import org.jboss.as.controller.descriptions.ResourceDescriptionResolver;
import org.jboss.as.controller.operations.validation.MapValidator;
import org.jboss.as.controller.operations.validation.NillableOrExpressionParameterValidator;
import org.jboss.as.controller.operations.validation.ParameterValidator;
import org.jboss.as.controller.parsing.ParseUtils;
import org.jboss.dmr.ModelNode;
import org.jboss.dmr.ModelType;
import org.jboss.dmr.Property;
import org.jboss.staxmapper.XMLExtendedStreamReader;
import org.wildfly.common.Assert;

/**
 * Defining characteristics of an {@link ModelType#OBJECT} attribute in a {@link org.jboss.as.controller.registry.Resource},
 * where all children of the object have values of the same type; i.e. the attribute represents a logical map of
 * arbitrary key value pairs.
 *
 * @author Brian Stansberry (c) 2011 Red Hat Inc.
 */
public abstract class MapAttributeDefinition extends AttributeDefinition {

    private final ParameterValidator elementValidator;

    protected MapAttributeDefinition(Builder<? extends Builder, ? extends MapAttributeDefinition> builder) {
        super(builder);
        this.elementValidator = builder.getElementValidator();
    }

    /**
     * Creates and returns a {@link ModelNode} using the given {@code value} after first validating the node
     * against {@link #getValidator() this object's validator}.
     * <p>
     * If {@code value} is {@code null} and a {@link #getDefaultValue() default value} is available, the value of that
     * default value will be used.
     * </p>
     *
     * @param value the value. Will be {@link String#trim() trimmed} before use if not {@code null}.
     * @param location current location of the parser's {@link javax.xml.stream.XMLStreamReader}. Used for any exception
     *                 message
     *
     * @return {@code ModelNode} representing the parsed value
     *
     * @throws XMLStreamException if {@code value} is not valid
     */
    public ModelNode parse(final String value, final Location location) throws XMLStreamException {
        ModelNode node = ParseUtils.parseAttributeValue(value, isAllowExpression(), getType());
        try {
            elementValidator.validateParameter(getXmlName(), node);
        } catch (OperationFailedException e) {
            throw new XMLStreamException(e.getFailureDescription().toString(), location);
        }

        return node;
    }

    public void parseAndAddParameterElement(final String key, final String value, final ModelNode operation, final XMLExtendedStreamReader reader) throws XMLStreamException {
        ModelNode paramVal = parse(value, reader.getLocation());
        operation.get(getName()).get(key).set(paramVal);
    }

    @Override
    public ModelNode addResourceAttributeDescription(ResourceBundle bundle, String prefix, ModelNode resourceDescription) {
        final ModelNode result = super.addResourceAttributeDescription(bundle, prefix, resourceDescription);
        addValueTypeDescription(result, bundle);
        return result;
    }

    @Override
    public ModelNode addOperationParameterDescription(ResourceBundle bundle, String prefix, ModelNode operationDescription) {
        final ModelNode result = super.addOperationParameterDescription(bundle, prefix, operationDescription);
        addValueTypeDescription(result, bundle);
        return result;
    }

    /**
     * The validator used to validate values in the map.
     * @return  the element validator
     */
    public ParameterValidator getElementValidator() {
        return elementValidator;
    }

    protected abstract void addValueTypeDescription(final ModelNode node, final ResourceBundle bundle);

    @Override
    public ModelNode addResourceAttributeDescription(ModelNode resourceDescription, ResourceDescriptionResolver resolver,
                                                     Locale locale, ResourceBundle bundle) {
        final ModelNode result = super.addResourceAttributeDescription(resourceDescription, resolver, locale, bundle);
        addAttributeValueTypeDescription(result, resolver, locale, bundle);
        return result;
    }

    protected abstract void addAttributeValueTypeDescription(ModelNode result, ResourceDescriptionResolver resolver, Locale locale, ResourceBundle bundle);

    @Override
    public ModelNode addOperationParameterDescription(ModelNode resourceDescription, String operationName,
                                                      ResourceDescriptionResolver resolver, Locale locale, ResourceBundle bundle) {
        final ModelNode result = super.addOperationParameterDescription(resourceDescription, operationName, resolver, locale, bundle);
        addOperationParameterValueTypeDescription(result, operationName, resolver, locale, bundle);
        return result;
    }

        @Override
    public ModelNode addOperationReplyDescription(ModelNode resourceDescription, String operationName,
                                                      ResourceDescriptionResolver resolver, Locale locale, ResourceBundle bundle) {
        final ModelNode result = super.addOperationReplyDescription(resourceDescription, operationName, resolver, locale, bundle);
        //TODO WFCORE-1178: use reply value types description instead of parameter value type
        addOperationParameterValueTypeDescription(result, operationName, resolver, locale, bundle);
        return result;
    }

    protected abstract void addOperationParameterValueTypeDescription(ModelNode result, String operationName, ResourceDescriptionResolver resolver, Locale locale, ResourceBundle bundle);

    @Override
    public void marshallAsElement(ModelNode resourceModel, boolean marshallDefault, XMLStreamWriter writer) throws XMLStreamException {
        if (getMarshaller().isMarshallable(this,resourceModel,marshallDefault)){
            getMarshaller().marshallAsElement(this, resourceModel, marshallDefault, writer);
        }
    }

    /**
     * Iterates through the items in the {@code parameter} map, calling {@link #convertParameterElementExpressions(ModelNode)}
     * for each value.
     * <p>
     * <strong>Note</strong> that the default implementation of {@link #convertParameterElementExpressions(ModelNode)}
     * will only convert simple {@link ModelType#STRING} values. If users need to handle complex values
     * with embedded expressions, they should use a subclass that overrides that method.
     * </p>
     *
     * {@inheritDoc}
     */
    @Override
    protected ModelNode convertParameterExpressions(ModelNode parameter) {
        ModelNode result = parameter;

        List<Property> asList;
        try {
            asList = parameter.asPropertyList();
        } catch (IllegalArgumentException iae) {
            // We can't convert; we'll just return parameter
            asList = null;
        }

        if (asList != null) {
            boolean changeMade = false;
            ModelNode newMap = new ModelNode().setEmptyObject();
            for (Property prop : parameter.asPropertyList()) {
                ModelNode converted = convertParameterElementExpressions(prop.getValue());
                newMap.get(prop.getName()).set(converted);
                changeMade |= !converted.equals(prop.getValue());
            }
            if (changeMade) {
                result = newMap;
            }
        }
        return result;
    }

    /**
     * Examine the given value item of a parameter map for any expression syntax, converting the relevant node to
     * {@link ModelType#EXPRESSION} if such is supported.
     *
     * @param parameterElementValue the node to examine. Will not be {@code null}
     * @return the parameter element value with expressions converted, or the original parameter if no conversion
     *         was performed. Cannot return {@code null}
     */
    protected ModelNode convertParameterElementExpressions(ModelNode parameterElementValue) {
        return isAllowExpression() ? convertStringExpression(parameterElementValue) : parameterElementValue;
    }

    public static final ParameterCorrector LIST_TO_MAP_CORRECTOR = new ParameterCorrector() {
        public ModelNode correct(ModelNode newValue, ModelNode currentValue) {
            if (newValue.isDefined()) {
                if (newValue.getType() == ModelType.LIST) {
                    int listSize = newValue.asList().size();
                    List<Property> propertyList = newValue.asPropertyList();
                    if (propertyList.isEmpty()) {
                        //The list cannot be converted to a map
                        if (listSize == 0) {
                            return new ModelNode();
                        }
                        if (listSize > 0) {
                            //It is a list of simple values, so just return the original
                            return newValue;
                        }
                    }
                    ModelNode corrected = new ModelNode();
                    for (Property p : newValue.asPropertyList()) {
                        corrected.get(p.getName()).set(p.getValue());
                    }
                    return corrected;
                }
            }
            return newValue;
        }
    };



    public abstract static class Builder<BUILDER extends Builder, ATTRIBUTE extends MapAttributeDefinition>
            extends AbstractAttributeDefinitionBuilder<BUILDER, ATTRIBUTE> {

        protected ParameterValidator elementValidator;
        private Boolean allowNullElement;

        protected Builder(String attributeName) {
            super(attributeName, ModelType.OBJECT);
        }

        protected Builder(String attributeName, boolean optional) {
            super(attributeName, ModelType.OBJECT, optional);
        }

        public Builder(MapAttributeDefinition basis) {
            super(basis);
            this.elementValidator = basis.getElementValidator();
            if (elementValidator instanceof NillableOrExpressionParameterValidator) {
                this.allowNullElement = ((NillableOrExpressionParameterValidator) elementValidator).getAllowNull();
            }
        }

        /**
         * Gets the validator to use for validating list elements. En
         * @return the validator, or {@code null} if no validator has been set
         */
        public ParameterValidator getElementValidator() {
            if (elementValidator == null) {
                return null;
            }

            ParameterValidator toWrap = elementValidator;
            ParameterValidator wrappedElementValidator = null;
            if (elementValidator instanceof NillableOrExpressionParameterValidator) {
                // See if it's configured correctly already; if so don't re-wrap
                NillableOrExpressionParameterValidator wrapped = (NillableOrExpressionParameterValidator) elementValidator;
                Boolean allow = wrapped.getAllowNull();
                if ((allow == null || allow) == getAllowNullElement()
                        && wrapped.isAllowExpression() == isAllowExpression()) {
                    wrappedElementValidator = wrapped;
                } else {
                    // re-wrap
                    toWrap = wrapped.getDelegate();
                }
            }
            if (wrappedElementValidator == null) {
                elementValidator = new NillableOrExpressionParameterValidator(toWrap, getAllowNullElement(), isAllowExpression());
            }
            return elementValidator;
        }

        /**
         * Sets the validator to use for validating list elements.
         *
         * @param elementValidator the validator
         * @return a builder that can be used to continue building the attribute definition
         *
         * @throws java.lang.IllegalArgumentException if {@code elementValidator} is {@code null}
         */
        @SuppressWarnings("unchecked")
        public final BUILDER setElementValidator(ParameterValidator elementValidator) {
            Assert.checkNotNullParam("elementValidator", elementValidator);
            this.elementValidator = elementValidator;
            // Setting an element validator invalidates any existing overall attribute validator
            super.setValidator(null);
            return (BUILDER) this;
        }

        /**
         * Overrides the superclass to simply delegate to
         * {@link #setElementValidator(org.jboss.as.controller.operations.validation.ParameterValidator)}.
         * Use {@link #setMapValidator(org.jboss.as.controller.operations.validation.ParameterValidator)} to
         * set an overall validator for the map.
         *
         * @param validator the validator. Cannot be {@code null}
         * @return a builder that can be used to continue building the attribute definition
         *
         * @throws java.lang.IllegalArgumentException if {@code elementValidator} is {@code null}
         */
        @Override
        public BUILDER setValidator(ParameterValidator validator) {
            return setElementValidator(validator);
        }

        /**
         * Sets an overall validator for the map.
         *
         * @param validator the validator. {@code null} is allowed
         * @return a builder that can be used to continue building the attribute definition
         */
        @SuppressWarnings("WeakerAccess")
        public BUILDER setMapValidator(ParameterValidator validator) {
            return super.setValidator(validator);
        }

        @Override
        public int getMinSize() {
            int min = super.getMinSize();
            if (min < 0) {
                min = 0;
                setMinSize(min);
            }
            return min;
        }

        @Override
        public int getMaxSize() {
            int max = super.getMaxSize();
            if (max < 1) {
                max = Integer.MAX_VALUE;
                setMaxSize(max);
            }
            return max;
        }

        /**
         * Gets whether undefined list elements are valid. In the unlikely case {@link #setAllowNullElement(boolean)}
         * has been called, that value is returned; otherwise the value of {@link #isNillable()} is used.
         *
         * @return {@code true} if undefined list elements are valid
         */
        public boolean getAllowNullElement() {
            return allowNullElement == null ? isNillable() : allowNullElement;
        }

        /**
         * Sets whether undefined list elements are valid.
         * @param allowNullElement whether undefined elements are valid
         * @return a builder that can be used to continue building the attribute definition
         */
        @SuppressWarnings({"unchecked", "WeakerAccess"})
        public BUILDER setAllowNullElement(boolean allowNullElement) {
            this.allowNullElement = allowNullElement;
            return (BUILDER) this;
        }

        @Override
        public ParameterValidator getValidator() {
            ParameterValidator result = super.getValidator();
            if (result == null) {
                ParameterValidator mapElementValidator = getElementValidator();
                // Subclasses must call setElementValidator before calling this
                assert mapElementValidator != null;
                result = new MapValidator(getElementValidator(), isNillable(), getMinSize(), getMaxSize());
            }
            return result;
        }
    }
}
