package de.deepamehta.core.impl;

import de.deepamehta.core.AssociationDefinition;
import de.deepamehta.core.DeepaMehtaObject;
import de.deepamehta.core.DeepaMehtaType;
import de.deepamehta.core.RelatedTopic;
import de.deepamehta.core.model.ChildTopicsModel;
import de.deepamehta.core.model.DeepaMehtaObjectModel;
import de.deepamehta.core.model.RelatedTopicModel;
import de.deepamehta.core.model.SimpleValue;

import org.codehaus.jettison.json.JSONObject;

import java.util.List;



/**
 * A DeepaMehta object model that is attached to the DB.
 *
 * Method name conventions and semantics:
 *  - getXX()           Reads from memory (model).
 *  - setXX(arg)        Writes to memory (model) and DB. Elementary operation.
 *  - updateXX(arg)     Compares arg with current value (model) and calls setXX() method(s) if required.
 *                      Can be called with arg=null which indicates no update is requested.
 *                      Typically returns nothing.
 *  - fetchXX()         Fetches value from DB.              ### FIXDOC
 *  - storeXX()         Stores current value (model) to DB. ### FIXDOC
 */
abstract class DeepaMehtaObjectImpl implements DeepaMehtaObject {

    // ---------------------------------------------------------------------------------------------- Instance Variables

    DeepaMehtaObjectModelImpl model;    // underlying model

    PersistenceLayer pl;
    ModelFactoryImpl mf;

    // ---------------------------------------------------------------------------------------------------- Constructors

    DeepaMehtaObjectImpl(DeepaMehtaObjectModelImpl model, PersistenceLayer pl) {
        this.model = model;
        this.pl = pl;
        this.mf = pl.mf;
    }

    // -------------------------------------------------------------------------------------------------- Public Methods



    // ***************************************
    // *** DeepaMehtaObject Implementation ***
    // ***************************************



    // === Model ===

    // --- ID ---

    @Override
    public final long getId() {
        return model.getId();
    }

    // --- URI ---

    @Override
    public final String getUri() {
        return model.getUri();
    }

    @Override
    public final void setUri(String uri) {
        model.updateUri(uri);
    }

    // --- Type URI ---

    @Override
    public final String getTypeUri() {
        return model.getTypeUri();
    }

    @Override
    public final void setTypeUri(String typeUri) {
        model.updateTypeUri(typeUri);
    }

    // --- Simple Value ---

    @Override
    public final SimpleValue getSimpleValue() {
        return model.getSimpleValue();
    }

    // ---

    @Override
    public final void setSimpleValue(String value) {
        setSimpleValue(new SimpleValue(value));
    }

    @Override
    public final void setSimpleValue(int value) {
        setSimpleValue(new SimpleValue(value));
    }

    @Override
    public final void setSimpleValue(long value) {
        setSimpleValue(new SimpleValue(value));
    }

    @Override
    public final void setSimpleValue(boolean value) {
        setSimpleValue(new SimpleValue(value));
    }

    @Override
    public final void setSimpleValue(SimpleValue value) {
        model.updateSimpleValue(value);
    }

    // --- Child Topics ---

    @Override
    public final ChildTopicsImpl getChildTopics() {
        return new ChildTopicsImpl(model.childTopics, model, pl);
    }

    // ### FIXME: no UPDATE directive for *this* object is added. No UPDATE event for *this* object is fired.
    // We should call the abstract updateWithChildTopics() instead.
    @Override
    public final void setChildTopics(ChildTopicsModel childTopics) {
        try {
            model._updateChildTopics((ChildTopicsModelImpl) childTopics);
        } catch (Exception e) {
            throw new RuntimeException("Setting the child topics failed (" + childTopics + ")", e);
        }
    }

    // ---

    @Override
    public DeepaMehtaObject loadChildTopics() {
        model.loadChildTopics();
        return this;
    }

    @Override
    public DeepaMehtaObject loadChildTopics(String assocDefUri) {
        model.loadChildTopics(assocDefUri);
        return this;
    }

    // ---

    @Override
    public final DeepaMehtaType getType() {
        return model.getType().instantiate();
    }

    @Override
    public DeepaMehtaObjectModelImpl getModel() {
        return model;
    }



    // === Updating ===

    // ### FIXME: no UPDATE directive for *this* object is added. No UPDATE event for *this* object is fired.
    // Directives/events is handled only in the high-level update() method.
    // Here however we need to call the low-level updateChildTopics() method in order to pass an arbitrary assoc def.
    @Override
    public final void updateChildTopic(RelatedTopicModel newChildTopic, AssociationDefinition assocDef) {
        model.updateChildTopics((RelatedTopicModelImpl) newChildTopic, null, assocDef.getModel());
            // newChildTopics=null
    }

    // ### FIXME: no UPDATE directive for *this* object is added. No UPDATE event for *this* object is fired.
    // Directives/events is handled only in the high-level update() method.
    // Here however we need to call the low-level updateChildTopics() method in order to pass an arbitrary assoc def.
    @Override
    public final void updateChildTopics(List<? extends RelatedTopicModel> newChildTopics,
                                        AssociationDefinition assocDef) {
        model.updateChildTopics(null, (List<RelatedTopicModelImpl>) newChildTopics, assocDef.getModel());
            // newChildTopic=null
    }



    // === Traversal ===

    // --- Topic Retrieval ---

    @Override
    public final RelatedTopic getRelatedTopic(String assocTypeUri, String myRoleTypeUri,
                                              String othersRoleTypeUri, String othersTopicTypeUri) {
        RelatedTopicModelImpl topic = model.getRelatedTopic(assocTypeUri, myRoleTypeUri, othersRoleTypeUri,
            othersTopicTypeUri);
        return topic != null ? pl.<RelatedTopic>checkReadAccessAndInstantiate(topic) : null;
    }

    @Override
    public final List<RelatedTopic> getRelatedTopics(String assocTypeUri) {
        return getRelatedTopics(assocTypeUri, null, null, null);
    }

    @Override
    public final List<RelatedTopic> getRelatedTopics(String assocTypeUri, String myRoleTypeUri,
                                                     String othersRoleTypeUri, String othersTopicTypeUri) {
        List<RelatedTopicModelImpl> topics = model.getRelatedTopics(assocTypeUri, myRoleTypeUri, othersRoleTypeUri,
            othersTopicTypeUri);
        return pl.checkReadAccessAndInstantiate(topics);
    }

    // Note: this method is implemented in the subclasses (this is an abstract class):
    //     getRelatedTopics(List assocTypeUris, ...)

    // --- Association Retrieval ---

    // Note: these methods are implemented in the subclasses (this is an abstract class):
    //     getAssociation(...)
    //     getAssociations()



    // === Properties ===

    @Override
    public final Object getProperty(String propUri) {
        return pl.fetchProperty(getId(), propUri);
    }

    @Override
    public final boolean hasProperty(String propUri) {
        return pl.hasProperty(getId(), propUri);
    }

    @Override
    public final void setProperty(String propUri, Object propValue, boolean addToIndex) {
        model.storeProperty(propUri, propValue, addToIndex);
    }

    @Override
    public final void removeProperty(String propUri) {
        model.removeProperty(propUri);
    }



    // === Misc ===

    @Override
    public final Object getDatabaseVendorObject() {
        return pl.getDatabaseVendorObject(getId());
    }



    // **********************************
    // *** JSONEnabled Implementation ***
    // **********************************



    @Override
    public final JSONObject toJSON() {
        return model.toJSON();
    }



    // ****************
    // *** Java API ***
    // ****************



    @Override
    public final boolean equals(Object o) {
        return ((DeepaMehtaObjectImpl) o).model.equals(model);
    }

    @Override
    public final int hashCode() {
        return model.hashCode();
    }

    @Override
    public final String toString() {
        return model.toString();
    }



    // ----------------------------------------------------------------------------------------- Package Private Methods

    final String className() {
        return model.className();
    }
}