/**
 * Different events will be fired when a catalog/database/table is modified. The customized listener can get and
 * report specific information from the event according to the event type.
 */
@PublicEvolving
public interface CatalogModificationListener {
    /** The event will be fired when the database/table is modified. */
    void onEvent(CatalogModificationEvent event, CatalogModificationContext context);
}

/* Basic interface for catalog modification. */
@PublicEvolving
public interface class CatalogModificationEvent {
    /* Context for the event. */
    CatalogModificationContext context();
}

/* Context for catalog modification and job lineage events. */
@PublicEvolving
public interface CatalogModificationContext {
    
    /* The name of catalog. */
    String getCatalogName();

    /* Class of the catalog. */
    Class<? extends Catalog> getClass();

    /* Identifier for the catalog from catalog factory, such as jdbc/iceberg/paimon. */
    Optional<String> getFactoryIdentifier();

    /* Config for catalog. */
    Configuration getConfiguration();
}

/* The basic class for database related event. */
public interface DatabaseModificationEvent extends CatalogModificationEvent {
    CatalogDatabase database();
}

/* Event for creating database. */
@PublicEvolving
public interface CreateDatabaseEvent extends DatabaseModificationEvent {
    boolean ignoreIfExists();
}

/* Event for altering database. */
@PublicEvolving
public interface AlterDatabaseEvent extends DatabaseModificationEvent {
    CatalogDatabase newDatabase();
    boolean ignoreIfNotExists();
}

/* Event for dropping database. */
@PublicEvolving
public interface DropDatabaseEvent extends DatabaseModificationEvent {
    boolean ignoreIfExists();
}

/**
 * Base table event, provides column list, primary keys, partition keys, watermarks and properties in
 * CatalogBaseTable. The table can be source or sink.
 */
public interface TableModificationEvent extends CatalogModificationEvent {
    ObjectIdentifier identifier();
    CatalogBaseTable table();
}

/* Event for creating table. */
@PublicEvolving
public interface CreateTableEvent extends CatalogModificationEvent {
    boolean ignoreIfExists();
}

/* Event for altering table, provides all changes for old table. */
@PublicEvolving
public interface AlterTableEvent extends CatalogModificationEvent {
    List<TableChange> tableChanges();
    boolean ignoreIfExists();
}

/* Event for dropping table. */
@PublicEvolving
public interface DropTableEvent extends CatalogModificationEvent {
    boolean ignoreIfExists();
}

/* Factory for catalog modification listener. */
@PublicEvolving
public interface CatalogModificationListenerFactory {
    CatalogModificationListener createListener(Context context);

    @PublicEvolving 
    public interface Context {
        Configuration getConfiguration();
        ClassLoader getUserClassLoader();
    	/*
    	* Get an Executor pool for the listener to run async operations that can potentially be IO-heavy.
    	*/
    	Executor getIOExecutor();
     }
}