package io.ebeaninternal.dbmigration.model.build;

import io.ebean.config.dbplatform.DbPlatformType;
import io.ebean.config.dbplatform.IdType;
import io.ebeaninternal.dbmigration.migration.IdentityType;
import io.ebeaninternal.dbmigration.model.MColumn;
import io.ebeaninternal.dbmigration.model.MTable;
import io.ebeaninternal.dbmigration.model.visitor.BeanVisitor;
import io.ebeaninternal.server.deploy.BeanDescriptor;
import io.ebeaninternal.server.deploy.BeanProperty;
import io.ebeaninternal.server.deploy.InheritInfo;

Used to build the Model objects MTable etc.
/**
 * Used to build the Model objects MTable etc.
 */
public class ModelBuildBeanVisitor implements BeanVisitor {

  private final ModelBuildContext ctx;

  public ModelBuildBeanVisitor(ModelBuildContext ctx) {
    this.ctx = ctx;
  }

  
Return the PropertyVisitor used to read all the property meta data
and in this case add MColumn objects to the model.

This creates an MTable and adds it to the model.

/**
   * Return the PropertyVisitor used to read all the property meta data
   * and in this case add MColumn objects to the model.
   * <p>
   * This creates an MTable and adds it to the model.
   * </p>
   */
  @Override
  public ModelBuildPropertyVisitor visitBean(BeanDescriptor<?> descriptor) {

    if (!descriptor.isInheritanceRoot()) {
      return null;
    }

    MTable table = new MTable(descriptor.getBaseTable());
    table.setStorageEngine(descriptor.getStorageEngine());
    table.setPartitionMeta(descriptor.getPartitionMeta());
    table.setComment(descriptor.getDbComment());
    if (descriptor.isHistorySupport()) {
      table.setWithHistory(true);
      BeanProperty whenCreated = descriptor.getWhenCreatedProperty();
      if (whenCreated != null) {
        table.setWhenCreatedColumn(whenCreated.getDbColumn());
      }
    }
    setIdentity(descriptor, table);

    // add the table to the model
    ctx.addTable(table);

    InheritInfo inheritInfo = descriptor.getInheritInfo();
    if (inheritInfo != null && inheritInfo.isRoot()) {
      // add the discriminator column
      String discColumn = inheritInfo.getDiscriminatorColumn();
      String columnDefn = inheritInfo.getColumnDefn();
      if (columnDefn == null || columnDefn.isEmpty()) {
        DbPlatformType dbType = ctx.getDbTypeMap().get(inheritInfo.getDiscriminatorType());
        columnDefn = dbType.renderType(inheritInfo.getColumnLength(), 0);
      }
      table.addColumn(new MColumn(discColumn, columnDefn, true));
    }

    return new ModelBuildPropertyVisitor(ctx, table, descriptor);
  }

  
Set the identity type to use for this table.

Takes into account the requested identity type and the underlying support in the
database platform.

/**
   * Set the identity type to use for this table.
   * <p>
   * Takes into account the requested identity type and the underlying support in the
   * database platform.
   * </p>
   */
  private void setIdentity(BeanDescriptor<?> descriptor, MTable table) {

    if (IdType.GENERATOR == descriptor.getIdType()) {
      // explicit generator like UUID
      table.setIdentityType(IdentityType.GENERATOR);
      return;
    }
    if (IdType.EXTERNAL == descriptor.getIdType()) {
      // externally defined code (lookup table, ISO country code etc)
      table.setIdentityType(IdentityType.EXTERNAL);
      return;
    }

    int initialValue = descriptor.getSequenceInitialValue();
    int allocationSize = descriptor.getSequenceAllocationSize();

    if (!descriptor.isIdTypePlatformDefault() || initialValue > 0 || allocationSize > 0) {
      // explicitly set to use sequence or identity (generally not recommended practice)
      if (IdType.IDENTITY == descriptor.getIdType()) {
        if (!descriptor.isIdTypePlatformDefault()) {
          table.setIdentityType(IdentityType.IDENTITY);
        }
      } else {
        // explicit sequence defined
        table.setIdentityType(IdentityType.SEQUENCE);
        table.setSequenceName(descriptor.getSequenceName());
        table.setSequenceInitial(initialValue);
        table.setSequenceAllocate(allocationSize);
      }
    }
  }

}