<?xml version="1.0" encoding="utf-8"?>
<databaseChangeLog
    xmlns="http://www.liquibase.org/xml/ns/dbchangelog"
    xmlns:ext="http://www.liquibase.org/xml/ns/dbchangelog-ext"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-3.5.xsd
                        http://www.liquibase.org/xml/ns/dbchangelog-ext http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-ext.xsd">

    <!-- Table for historical user data. -->
    <changeSet id="20190526160000-1" author="mhierweck,mhoennig" dbms="postgresql">

        <createTable tableName="jhi_user_authority_history">

            <!-- history-related columns -->

            <column name="history_id" type="bigint" autoIncrement="true">
                <constraints primaryKey="true" unique="true" nullable="false"/>
            </column>

            <column name="history_transaction" type="bigint">
                <constraints nullable="false" />
            </column>

            <column name="history_tombstone" type="bool">
                <constraints nullable="false" />
            </column>

            <!-- columns like in base table, dropping unique constraints -->

            <column name="user_id" type="bigint">
                <constraints nullable="false"/>
            </column>

            <column name="authority_name" type="varchar(50)">
                <constraints nullable="false"/>
            </column>

        </createTable>

    </changeSet>

    <changeSet id="20190526160000-2" author="mhierweck,mhoennig" dbms="postgresql">

        <addForeignKeyConstraint baseColumnNames="history_transaction"
                                 baseTableName="jhi_user_authority_history"
                                 constraintName="fk_jhi_user_authority_history_transaction"
                                 referencedColumnNames="history_transaction"
                                 referencedTableName="history"/>

    </changeSet>

    <changeSet id="20190526160000-3" author="mhierweck,mhoennig" dbms="postgresql">
        <createProcedure>
            CREATE TRIGGER jhi_user_authority_historicize
            AFTER INSERT OR DELETE OR UPDATE ON jhi_user_authority
            FOR EACH ROW EXECUTE PROCEDURE historicize();
        </createProcedure>
        <rollback>
            DROP TRIGGER jhi_user_authority_historicize
        </rollback>
    </changeSet>

    <changeSet id="20190526160000-4" author="mhierweck,mhoennig" dbms="postgresql">
        <createView viewName="jhi_user_authority_history_view" replaceIfExists="true">
            SELECT *
              FROM jhi_user_authority_history
             WHERE history_id IN (
                SELECT max(history_id) AS history_id
                  FROM jhi_user_authority_history
                 WHERE history_transaction &lt;= current_setting('history.transaction')::bigint
                 GROUP BY user_id, authority_name) -- must have a unique constraint
        </createView>
    </changeSet>

</databaseChangeLog>
