/**
 *
 * Copyright the original author or authors
 *
 * 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 org.jivesoftware.smackx.pubsub;

import java.util.ArrayList;
import java.util.List;

import org.jivesoftware.smackx.xdata.Form;
import org.jivesoftware.smackx.xdata.FormField;
import org.jivesoftware.smackx.xdata.packet.DataForm;

/**
 * A decorator for a {@link Form} to easily enable reading and updating
 * of node configuration.  All operations read or update the underlying {@link DataForm}.
 * 
 * <p>Unlike the {@link Form}.setAnswer(XXX)} methods, which throw an exception if the field does not
 * exist, all <b>ConfigureForm.setXXX</b> methods will create the field in the wrapped form
 * if it does not already exist. 
 * 
 * @author Robin Collier
 */
public class ConfigureForm extends Form
{
    /**
     * Create a decorator from an existing {@link DataForm} that has been
     * retrieved from parsing a node configuration request.
     * 
     * @param configDataForm
     */
    public ConfigureForm(DataForm configDataForm)
    {
        super(configDataForm);
    }

    /**
     * Create a decorator from an existing {@link Form} for node configuration.
     * Typically, this can be used to create a decorator for an answer form
     * by using the result of {@link #createAnswerForm()} as the input parameter.
     * 
     * @param nodeConfigForm
     */
    public ConfigureForm(Form nodeConfigForm)
    {
        super(nodeConfigForm.getDataFormToSend());
    }

    /**
     * Create a new form for configuring a node.  This would typically only be used 
     * when creating and configuring a node at the same time via {@link PubSubManager#createNode(String, Form)}, since 
     * configuration of an existing node is typically accomplished by calling {@link LeafNode#getNodeConfiguration()} and
     * using the resulting form to create a answer form.  See {@link #ConfigureForm(Form)}.
     * @param formType
     */
    public ConfigureForm(DataForm.Type formType)
    {
        super(formType);
    }

    /**
     * Get the currently configured {@link AccessModel}, null if it is not set.
     * 
     * @return The current {@link AccessModel}
     */
    public AccessModel getAccessModel()
    {
        String value = getFieldValue(ConfigureNodeFields.access_model);

        if (value == null)
            return null;
        else
            return AccessModel.valueOf(value);
    }

    /**
     * Sets the value of access model.
     * 
     * @param accessModel
     */
    public void setAccessModel(AccessModel accessModel)
    {
        addField(ConfigureNodeFields.access_model, FormField.Type.list_single);
        setAnswer(ConfigureNodeFields.access_model.getFieldName(), getListSingle(accessModel.toString()));
    }

    /**
     * Returns the URL of an XSL transformation which can be applied to payloads in order to 
     * generate an appropriate message body element.
     * 
     * @return URL to an XSL
     */
    public String getBodyXSLT()
    {
        return getFieldValue(ConfigureNodeFields.body_xslt);
    }

    /**
     * Set the URL of an XSL transformation which can be applied to payloads in order to 
     * generate an appropriate message body element.
     * 
     * @param bodyXslt The URL of an XSL
     */
    public void setBodyXSLT(String bodyXslt)
    {
        addField(ConfigureNodeFields.body_xslt, FormField.Type.text_single);
        setAnswer(ConfigureNodeFields.body_xslt.getFieldName(), bodyXslt);
    }

    /**
     * The id's of the child nodes associated with a collection node (both leaf and collection).
     * 
     * @return list of child nodes.
     */
    public List<String> getChildren()
    {
        return getFieldValues(ConfigureNodeFields.children);
    }

    /**
     * Set the list of child node ids that are associated with a collection node.
     * 
     * @param children
     */
    public void setChildren(List<String> children)
    {
        addField(ConfigureNodeFields.children, FormField.Type.text_multi);
        setAnswer(ConfigureNodeFields.children.getFieldName(), children);
    }

    /**
     * Returns the policy that determines who may associate children with the node.
     *  
     * @return The current policy
     */
    public ChildrenAssociationPolicy getChildrenAssociationPolicy()
    {
        String value = getFieldValue(ConfigureNodeFields.children_association_policy);

        if (value == null)
            return null;
        else
            return ChildrenAssociationPolicy.valueOf(value);
    }

    /**
     * Sets the policy that determines who may associate children with the node.
     * 
     * @param policy The policy being set
     */
    public void setChildrenAssociationPolicy(ChildrenAssociationPolicy policy)
    {
        addField(ConfigureNodeFields.children_association_policy, FormField.Type.list_single);
        List<String> values = new ArrayList<>(1);
        values.add(policy.toString());
        setAnswer(ConfigureNodeFields.children_association_policy.getFieldName(), values);
    }

    /**
     * List of JID's that are on the whitelist that determines who can associate child nodes 
     * with the collection node.  This is only relevant if {@link #getChildrenAssociationPolicy()} is set to
     * {@link ChildrenAssociationPolicy#whitelist}.
     * 
     * @return List of the whitelist
     */
    public List<String> getChildrenAssociationWhitelist()
    {
        return getFieldValues(ConfigureNodeFields.children_association_whitelist);
    }

    /**
     * Set the JID's in the whitelist of users that can associate child nodes with the collection 
     * node.  This is only relevant if {@link #getChildrenAssociationPolicy()} is set to
     * {@link ChildrenAssociationPolicy#whitelist}.
     * 
     * @param whitelist The list of JID's
     */
    public void setChildrenAssociationWhitelist(List<String> whitelist)
    {
        addField(ConfigureNodeFields.children_association_whitelist, FormField.Type.jid_multi);
        setAnswer(ConfigureNodeFields.children_association_whitelist.getFieldName(), whitelist);
    }

    /**
     * Gets the maximum number of child nodes that can be associated with the collection node.
     * 
     * @return The maximum number of child nodes
     */
    public int getChildrenMax()
    {
        return Integer.parseInt(getFieldValue(ConfigureNodeFields.children_max));
    }

    /**
     * Set the maximum number of child nodes that can be associated with a collection node.
     * 
     * @param max The maximum number of child nodes.
     */
    public void setChildrenMax(int max)
    {
        addField(ConfigureNodeFields.children_max, FormField.Type.text_single);
        setAnswer(ConfigureNodeFields.children_max.getFieldName(), max);
    }

    /**
     * Gets the collection node which the node is affiliated with.
     * 
     * @return The collection node id
     */
    public String getCollection()
    {
        return getFieldValue(ConfigureNodeFields.collection);
    }

    /**
     * Sets the collection node which the node is affiliated with.
     * 
     * @param collection The node id of the collection node
     */
    public void setCollection(String collection)
    {
        addField(ConfigureNodeFields.collection, FormField.Type.text_single);
        setAnswer(ConfigureNodeFields.collection.getFieldName(), collection);
    }

    /**
     * Gets the URL of an XSL transformation which can be applied to the payload
     * format in order to generate a valid Data Forms result that the client could
     * display using a generic Data Forms rendering engine.
     * 
     * @return The URL of an XSL transformation
     */
    public String getDataformXSLT()
    {
        return getFieldValue(ConfigureNodeFields.dataform_xslt);
    }

    /**
     * Sets the URL of an XSL transformation which can be applied to the payload
     * format in order to generate a valid Data Forms result that the client could
     * display using a generic Data Forms rendering engine.
     * 
     * @param url The URL of an XSL transformation
     */
    public void setDataformXSLT(String url)
    {
        addField(ConfigureNodeFields.dataform_xslt, FormField.Type.text_single);
        setAnswer(ConfigureNodeFields.dataform_xslt.getFieldName(), url);
    }

    /**
     * Does the node deliver payloads with event notifications.
     * 
     * @return true if it does, false otherwise
     */
    public boolean isDeliverPayloads()
    {
        return parseBoolean(getFieldValue(ConfigureNodeFields.deliver_payloads));
    }

    /**
     * Sets whether the node will deliver payloads with event notifications.
     * 
     * @param deliver true if the payload will be delivered, false otherwise
     */
    public void setDeliverPayloads(boolean deliver)
    {
        addField(ConfigureNodeFields.deliver_payloads, FormField.Type.bool);
        setAnswer(ConfigureNodeFields.deliver_payloads.getFieldName(), deliver);
    }

    /**
     * Determines who should get replies to items.
     * 
     * @return Who should get the reply
     */
    public ItemReply getItemReply()
    {
        String value = getFieldValue(ConfigureNodeFields.itemreply);

        if (value == null)
            return null;
        else
            return ItemReply.valueOf(value);
    }

    /**
     * Sets who should get the replies to items.
     * 
     * @param reply Defines who should get the reply
     */
    public void setItemReply(ItemReply reply)
    {
        addField(ConfigureNodeFields.itemreply, FormField.Type.list_single);
        setAnswer(ConfigureNodeFields.itemreply.getFieldName(), getListSingle(reply.toString()));
    }

    /**
     * Gets the maximum number of items to persisted to this node if {@link #isPersistItems()} is
     * true.
     * 
     * @return The maximum number of items to persist
     */
    public int getMaxItems()
    {
        return Integer.parseInt(getFieldValue(ConfigureNodeFields.max_items));
    }

    /**
     * Set the maximum number of items to persisted to this node if {@link #isPersistItems()} is
     * true.
     * 
     * @param max The maximum number of items to persist
     */
    public void setMaxItems(int max)
    {
        addField(ConfigureNodeFields.max_items, FormField.Type.text_single);
        setAnswer(ConfigureNodeFields.max_items.getFieldName(), max);
    }

    /**
     * Gets the maximum payload size in bytes.
     * 
     * @return The maximum payload size
     */
    public int getMaxPayloadSize()
    {
        return Integer.parseInt(getFieldValue(ConfigureNodeFields.max_payload_size));
    }

    /**
     * Sets the maximum payload size in bytes.
     * 
     * @param max The maximum payload size
     */
    public void setMaxPayloadSize(int max)
    {
        addField(ConfigureNodeFields.max_payload_size, FormField.Type.text_single);
        setAnswer(ConfigureNodeFields.max_payload_size.getFieldName(), max);
    }

    /**
     * Gets the node type.
     * 
     * @return The node type
     */
    public NodeType getNodeType()
    {
        String value = getFieldValue(ConfigureNodeFields.node_type);

        if (value == null)
            return null;
        else
            return NodeType.valueOf(value);
    }

    /**
     * Sets the node type.
     * 
     * @param type The node type
     */
    public void setNodeType(NodeType type)
    {
        addField(ConfigureNodeFields.node_type, FormField.Type.list_single);
        setAnswer(ConfigureNodeFields.node_type.getFieldName(), getListSingle(type.toString()));
    }

    /**
     * Determines if subscribers should be notified when the configuration changes.
     * 
     * @return true if they should be notified, false otherwise
     */
    public boolean isNotifyConfig()
    {
        return parseBoolean(getFieldValue(ConfigureNodeFields.notify_config));
    }

    /**
     * Sets whether subscribers should be notified when the configuration changes.
     * 
     * @param notify true if subscribers should be notified, false otherwise
     */
    public void setNotifyConfig(boolean notify)
    {
        addField(ConfigureNodeFields.notify_config, FormField.Type.bool);
        setAnswer(ConfigureNodeFields.notify_config.getFieldName(), notify);
    }

    /**
     * Determines whether subscribers should be notified when the node is deleted.
     * 
     * @return true if subscribers should be notified, false otherwise
     */
    public boolean isNotifyDelete()
    {
        return parseBoolean(getFieldValue(ConfigureNodeFields.notify_delete));
    }

    /**
     * Sets whether subscribers should be notified when the node is deleted.
     * 
     * @param notify true if subscribers should be notified, false otherwise
     */
    public void setNotifyDelete(boolean notify) 
    {
        addField(ConfigureNodeFields.notify_delete, FormField.Type.bool);
        setAnswer(ConfigureNodeFields.notify_delete.getFieldName(), notify);
    }

    /**
     * Determines whether subscribers should be notified when items are deleted 
     * from the node.
     * 
     * @return true if subscribers should be notified, false otherwise
     */
    public boolean isNotifyRetract()
    {
        return parseBoolean(getFieldValue(ConfigureNodeFields.notify_retract));
    }

    /**
     * Sets whether subscribers should be notified when items are deleted 
     * from the node.
     * 
     * @param notify true if subscribers should be notified, false otherwise
     */
    public void setNotifyRetract(boolean notify) 
    {
        addField(ConfigureNodeFields.notify_retract, FormField.Type.bool);
        setAnswer(ConfigureNodeFields.notify_retract.getFieldName(), notify);
    }

    /**
     * Determines whether items should be persisted in the node.
     * 
     * @return true if items are persisted
     */
    public boolean isPersistItems()
    {
        return parseBoolean(getFieldValue(ConfigureNodeFields.persist_items));
    }

    /**
     * Sets whether items should be persisted in the node.
     * 
     * @param persist true if items should be persisted, false otherwise
     */
    public void setPersistentItems(boolean persist) 
    {
        addField(ConfigureNodeFields.persist_items, FormField.Type.bool);
        setAnswer(ConfigureNodeFields.persist_items.getFieldName(), persist);
    }

    /**
     * Determines whether to deliver notifications to available users only.
     * 
     * @return true if users must be available
     */
    public boolean isPresenceBasedDelivery()
    {
        return parseBoolean(getFieldValue(ConfigureNodeFields.presence_based_delivery));
    }

    /**
     * Sets whether to deliver notifications to available users only.
     * 
     * @param presenceBased true if user must be available, false otherwise
     */
    public void setPresenceBasedDelivery(boolean presenceBased) 
    {
        addField(ConfigureNodeFields.presence_based_delivery, FormField.Type.bool);
        setAnswer(ConfigureNodeFields.presence_based_delivery.getFieldName(), presenceBased);
    }

    /**
     * Gets the publishing model for the node, which determines who may publish to it.
     * 
     * @return The publishing model
     */
    public PublishModel getPublishModel()
    {
        String value = getFieldValue(ConfigureNodeFields.publish_model);

        if (value == null)
            return null;
        else
            return PublishModel.valueOf(value);
    }

    /**
     * Sets the publishing model for the node, which determines who may publish to it.
     * 
     * @param publish The enum representing the possible options for the publishing model
     */
    public void setPublishModel(PublishModel publish) 
    {
        addField(ConfigureNodeFields.publish_model, FormField.Type.list_single);
        setAnswer(ConfigureNodeFields.publish_model.getFieldName(), getListSingle(publish.toString()));
    }

    /**
     * List of the multi user chat rooms that are specified as reply rooms.
     * 
     * @return The reply room JID's
     */
    public List<String> getReplyRoom()
    {
        return getFieldValues(ConfigureNodeFields.replyroom);
    }

    /**
     * Sets the multi user chat rooms that are specified as reply rooms.
     * 
     * @param replyRooms The multi user chat room to use as reply rooms
     */
    public void setReplyRoom(List<String> replyRooms) 
    {
        addField(ConfigureNodeFields.replyroom, FormField.Type.list_multi);
        setAnswer(ConfigureNodeFields.replyroom.getFieldName(), replyRooms);
    }

    /**
     * Gets the specific JID's for reply to.
     *  
     * @return The JID's
     */
    public List<String> getReplyTo()
    {
        return getFieldValues(ConfigureNodeFields.replyto);
    }

    /**
     * Sets the specific JID's for reply to.
     * 
     * @param replyTos The JID's to reply to
     */
    public void setReplyTo(List<String> replyTos)
    {
        addField(ConfigureNodeFields.replyto, FormField.Type.list_multi);
        setAnswer(ConfigureNodeFields.replyto.getFieldName(), replyTos);
    }

    /**
     * Gets the roster groups that are allowed to subscribe and retrieve items.
     *  
     * @return The roster groups
     */
    public List<String> getRosterGroupsAllowed()
    {
        return getFieldValues(ConfigureNodeFields.roster_groups_allowed);
    }

    /**
     * Sets the roster groups that are allowed to subscribe and retrieve items.
     * 
     * @param groups The roster groups
     */
    public void setRosterGroupsAllowed(List<String> groups)
    {
        addField(ConfigureNodeFields.roster_groups_allowed, FormField.Type.list_multi);
        setAnswer(ConfigureNodeFields.roster_groups_allowed.getFieldName(), groups);
    }

    /**
     * Determines if subscriptions are allowed.
     * 
     * @return true if subscriptions are allowed, false otherwise
     * @deprecated use {@link #isSubscribe()} instead
     */
    @Deprecated
    public boolean isSubscibe()
    {
        return isSubscribe();
    }

    /**
     * Determines if subscriptions are allowed.
     * 
     * @return true if subscriptions are allowed, false otherwise
     */
    public boolean isSubscribe() {
        return parseBoolean(getFieldValue(ConfigureNodeFields.subscribe));
    }

    /**
     * Sets whether subscriptions are allowed.
     * 
     * @param subscribe true if they are, false otherwise
     */
    public void setSubscribe(boolean subscribe)
    {
        addField(ConfigureNodeFields.subscribe, FormField.Type.bool);
        setAnswer(ConfigureNodeFields.subscribe.getFieldName(), subscribe);
    }

    /**
     * Gets the human readable node title.
     * 
     * @return The node title
     */
    @Override
    public String getTitle()
    {
        return getFieldValue(ConfigureNodeFields.title);
    }

    /**
     * Sets a human readable title for the node.
     * 
     * @param title The node title
     */
    @Override
    public void setTitle(String title) 
    {
        addField(ConfigureNodeFields.title, FormField.Type.text_single);
        setAnswer(ConfigureNodeFields.title.getFieldName(), title);
    }

    /**
     * The type of node data, usually specified by the namespace of the payload (if any).
     * 
     * @return The type of node data
     */
    public String getDataType()
    {
        return getFieldValue(ConfigureNodeFields.type);
    }

    /**
     * Sets the type of node data, usually specified by the namespace of the payload (if any).
     * 
     * @param type The type of node data
     */
    public void setDataType(String type) 
    {
        addField(ConfigureNodeFields.type, FormField.Type.text_single);
        setAnswer(ConfigureNodeFields.type.getFieldName(), type);
    }

    @Override
    public String toString()
    {
        StringBuilder result = new StringBuilder(getClass().getName() + " Content [");

        for (FormField formField : getFields())
        {
            result.append('(');
            result.append(formField.getVariable());
            result.append(':');

            StringBuilder valuesBuilder = new StringBuilder();

            for (String value : formField.getValues())
            {
                if (valuesBuilder.length() > 0)
                    result.append(',');
                valuesBuilder.append(value);
            }

            if (valuesBuilder.length() == 0)
                valuesBuilder.append("NOT SET");
            result.append(valuesBuilder);
            result.append(')');
        }
        result.append(']');
        return result.toString();
    }

    static private boolean parseBoolean(String fieldValue)
    {
        return ("1".equals(fieldValue) || "true".equals(fieldValue));
    }

    private String getFieldValue(ConfigureNodeFields field)
    {
        FormField formField = getField(field.getFieldName());

        return (formField.getValues().isEmpty()) ? null : formField.getValues().get(0);
    }

    private List<String> getFieldValues(ConfigureNodeFields field)
    {
        FormField formField = getField(field.getFieldName());

        return formField.getValues();
    }

    private void addField(ConfigureNodeFields nodeField, FormField.Type type)
    {
        String fieldName = nodeField.getFieldName();

        if (getField(fieldName) == null)
        {
            FormField field = new FormField(fieldName);
            field.setType(type);
            addField(field);
        }
    }

    private static List<String> getListSingle(String value)
    {
        List<String> list = new ArrayList<>(1);
        list.add(value);
        return list;
    }

}