/*
 * Copyright 2015, The Querydsl Team (http://www.querydsl.com/team)
 *
 * 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 com.querydsl.jpa.codegen.ant;

import java.io.File;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;

import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
import javax.persistence.metamodel.Metamodel;

import com.google.common.collect.ImmutableSet;
import com.querydsl.jpa.codegen.JPADomainExporter;

/**
 * {@code AntJPADomainExporter} exports JPA 2 metamodels to Querydsl expression types
 *
 * @author 200003548
 */
public class AntJPADomainExporter {

    /**
     * Additional property to use when creating the JPA entity manager factory
     */
    public static class Property {
        private String name;
        private String value;
        public String getName() {
            return name;
        }
        public void setName(String name) {
            this.name = name;
        }
        public String getValue() {
            return value;
        }
        public void setValue(String value) {
            this.value = value;
        }
    }

    /**
     * Set of additional properties to use when creating the JPA entity manager factory
     */
    public static class Configuration {
        private Map<String, String> properties = new HashMap<String, String>();
        public Map<String, String> getProperties() {
            return properties;
        }
        public void addConfiguredProperty(Property property) {
            properties.put(property.getName(), property.getValue());
        }
    }

    /**
     * Set of additional properties to use when creating the JPA entity manager factory
     * (no default - not required)
     */
    private Configuration configuration;

    /**
     * Name prefix for generated query types (default: "Q")
     */
    private String namePrefix = "Q";

    /**
     * Name suffix for generated query types (default: "")
     */
    private String nameSuffix = "";

    /**
     * Target folder in which to generate query types (no default - required)
     */
    private String targetFolder;

    /**
     * Name of persistence unit from which to generate query types (no default - required)
     */
    private String persistenceUnitName;

    private Set<File> generatedFiles = ImmutableSet.of();

    public Configuration getConfiguration() {
        return configuration;
    }

    public void addConfiguration(Configuration configuration) {
        this.configuration = configuration;
    }

    public String getNamePrefix() {
        return namePrefix;
    }

    public void setNamePrefix(String namePrefix) {
        this.namePrefix = namePrefix;
    }

    public String getNameSuffix() {
        return nameSuffix;
    }

    public void setNameSuffix(String nameSuffix) {
        this.nameSuffix = nameSuffix;
    }

    public String getTargetFolder() {
        return targetFolder;
    }

    public void setTargetFolder(String targetFolder) {
        this.targetFolder = targetFolder;
    }

    public String getPersistenceUnitName() {
        return persistenceUnitName;
    }

    public void setPersistenceUnitName(String persistenceUnitName) {
        this.persistenceUnitName = persistenceUnitName;
    }

    public Set<File> getGeneratedFiles() {
        return generatedFiles;
    }

    /**
     * Exports the named persistence unit's metamodel to Querydsl query types.  Expects to be
     * called by Ant via name convention using a method with signature public void execute().
     */
    public void execute() {
        // We can assume we have the named persistence unit and its mapping file in our classpath,
        // but we may have to allow some properties in that persistence unit to be overridden before
        // we can successfully get that persistence unit's metamodel.
        Map<String, String> properties = (configuration != null) ? configuration.getProperties() : null;
        EntityManagerFactory emf = Persistence.createEntityManagerFactory(persistenceUnitName, properties);

        // Now we can get the persistence unit's metamodel and export it to Querydsl query types.
        Metamodel configuration = emf.getMetamodel();
        JPADomainExporter exporter = new JPADomainExporter(namePrefix, nameSuffix, new File(targetFolder), configuration);
        try {
            exporter.execute();
            generatedFiles = exporter.getGeneratedFiles();
        } catch (IOException e) {
            throw new RuntimeException("Error in JPADomainExporter", e);
        }
    }

}