/*
 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
 *
 * 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.jbpm.process.instance.context.variable;

import java.util.Collections;
import java.util.HashMap;
import java.util.Map;

import org.jbpm.process.core.context.variable.Variable;
import org.jbpm.process.core.context.variable.VariableScope;
import org.jbpm.process.instance.ContextInstanceContainer;
import org.jbpm.process.instance.InternalProcessRuntime;
import org.jbpm.process.instance.context.AbstractContextInstance;
import org.jbpm.workflow.core.Node;
import org.jbpm.workflow.instance.node.CompositeContextNodeInstance;
import org.kie.kogito.internal.process.event.KogitoProcessEventSupport;
import org.kie.kogito.internal.process.runtime.KogitoNodeInstance;
import org.kie.kogito.process.VariableViolationException;

/**
 * 
 */
public class VariableScopeInstance extends AbstractContextInstance {

    private static final long serialVersionUID = 510l;

    private Map<String, Object> variables = new HashMap<String, Object>();
    private transient String variableIdPrefix = null;
    private transient String variableInstanceIdPrefix = null;

    public String getContextType() {
        return VariableScope.VARIABLE_SCOPE;
    }

    public Object getVariable(String name) {

        Object value = variables.get(name);
        if (value != null) {
            return value;
        }

        // support for processInstanceId and parentProcessInstanceId
        if ("processInstanceId".equals(name) && getProcessInstance() != null) {
            return getProcessInstance().getId();
        } else if ("parentProcessInstanceId".equals(name) && getProcessInstance() != null) {
            return getProcessInstance().getParentProcessInstanceId();
        }

        if (getProcessInstance() != null && getProcessInstance().getKnowledgeRuntime() != null) {
            // support for globals
            value = getProcessInstance().getKnowledgeRuntime().getGlobal(name);
            if (value != null) {
                return value;
            }

        }

        return null;
    }

    public Map<String, Object> getVariables() {
        return Collections.unmodifiableMap(variables);
    }

    public void setVariable(String name, Object value) {
        setVariable(null, name, value);
    }

    public void setVariable(KogitoNodeInstance nodeInstance, String name, Object value) {
        if (name == null) {
            throw new IllegalArgumentException(
                    "The name of a variable may not be null!");
        }
        Object oldValue = getVariable(name);
        if (oldValue == null) {
            if (value == null) {
                return;
            }
        }

        // check if variable that is being set is readonly and has already been set
        if (oldValue != null && getVariableScope().isReadOnly(name)) {
            throw new VariableViolationException(getProcessInstance().getStringId(), name, "Variable '" + name + "' is already set and is marked as read only");
        }
        KogitoProcessEventSupport processEventSupport = (KogitoProcessEventSupport) ((InternalProcessRuntime) getProcessInstance()
                .getKnowledgeRuntime().getProcessRuntime()).getProcessEventSupport();
        processEventSupport.fireBeforeVariableChanged(
                (variableIdPrefix == null ? "" : variableIdPrefix + ":") + name,
                (variableInstanceIdPrefix == null ? "" : variableInstanceIdPrefix + ":") + name,
                oldValue, value, getVariableScope().tags(name), getProcessInstance(),
                nodeInstance,
                getProcessInstance().getKnowledgeRuntime());
        internalSetVariable(name, value);
        processEventSupport.fireAfterVariableChanged(
                (variableIdPrefix == null ? "" : variableIdPrefix + ":") + name,
                (variableInstanceIdPrefix == null ? "" : variableInstanceIdPrefix + ":") + name,
                oldValue, value, getVariableScope().tags(name), getProcessInstance(),
                nodeInstance,
                getProcessInstance().getKnowledgeRuntime());
    }

    public void internalSetVariable(String name, Object value) {
        // not a case, store it in normal variables
        variables.put(name, value);
    }

    public VariableScope getVariableScope() {
        return (VariableScope) getContext();
    }

    public void setContextInstanceContainer(ContextInstanceContainer contextInstanceContainer) {
        super.setContextInstanceContainer(contextInstanceContainer);
        for (Variable variable : getVariableScope().getVariables()) {
            if (variable.getValue() != null) {
                setVariable(variable.getName(), variable.getValue());
            }
        }
        if (contextInstanceContainer instanceof CompositeContextNodeInstance) {
            this.variableIdPrefix = ((Node) ((CompositeContextNodeInstance) contextInstanceContainer).getNode()).getUniqueId();
            this.variableInstanceIdPrefix = ((CompositeContextNodeInstance) contextInstanceContainer).getUniqueId();
        }
    }

    public void enforceRequiredVariables() {
        VariableScope variableScope = getVariableScope();
        for (Variable variable : variableScope.getVariables()) {
            if (variableScope.isRequired(variable.getName()) && !variables.containsKey(variable.getName())) {
                throw new VariableViolationException(getProcessInstance().getStringId(), variable.getName(), "Variable '" + variable.getName() + "' is required but not set");
            }
        }
    }
}
