-- complain if script is sourced in psql, rather than via CREATE EXTENSION
\echo Use "CREATE EXTENSION repmgr" to load this file. \quit

CREATE TABLE repmgr.nodes (
  node_id          INTEGER     PRIMARY KEY,
  upstream_node_id INTEGER     NULL REFERENCES nodes (node_id) DEFERRABLE,
  active           BOOLEAN     NOT NULL DEFAULT TRUE,
  node_name        TEXT        NOT NULL,
  type             TEXT        NOT NULL CHECK (type IN('primary','standby','witness','bdr','bdr_standby')),
  location         TEXT        NOT NULL DEFAULT 'default',
  priority         INT         NOT NULL DEFAULT 100,
  conninfo         TEXT        NOT NULL,
  repluser         VARCHAR(63) NOT NULL,
  slot_name        TEXT        NULL,
  config_file      TEXT        NOT NULL
);

CREATE TABLE repmgr.events (
  node_id          INTEGER NOT NULL,
  event            TEXT NOT NULL,
  successful       BOOLEAN NOT NULL DEFAULT TRUE,
  event_timestamp  TIMESTAMP WITH TIME ZONE NOT NULL DEFAULT CURRENT_TIMESTAMP,
  details          TEXT NULL
);

DO $repmgr$
DECLARE
  DECLARE server_version_num INT;
BEGIN
  SELECT setting
    FROM pg_catalog.pg_settings
   WHERE name = 'server_version_num'
    INTO server_version_num;
  IF server_version_num >= 90400 THEN
    EXECUTE $repmgr_func$
CREATE TABLE repmgr.monitoring_history (
  primary_node_id                INTEGER NOT NULL,
  standby_node_id                INTEGER NOT NULL,
  last_monitor_time              TIMESTAMP WITH TIME ZONE NOT NULL,
  last_apply_time                TIMESTAMP WITH TIME ZONE,
  last_wal_primary_location      PG_LSN NOT NULL,
  last_wal_standby_location      PG_LSN,
  replication_lag                BIGINT NOT NULL,
  apply_lag                      BIGINT NOT NULL
)
    $repmgr_func$;
  ELSE
    EXECUTE $repmgr_func$
CREATE TABLE repmgr.monitoring_history (
  primary_node_id                INTEGER NOT NULL,
  standby_node_id                INTEGER NOT NULL,
  last_monitor_time              TIMESTAMP WITH TIME ZONE NOT NULL,
  last_apply_time                TIMESTAMP WITH TIME ZONE,
  last_wal_primary_location      TEXT NOT NULL,
  last_wal_standby_location      TEXT,
  replication_lag                BIGINT NOT NULL,
  apply_lag                      BIGINT NOT NULL
)
    $repmgr_func$;
  END IF;
END$repmgr$;



CREATE INDEX idx_monitoring_history_time
          ON repmgr.monitoring_history (last_monitor_time, standby_node_id);

CREATE VIEW repmgr.show_nodes AS
   SELECT n.node_id,
          n.node_name,
          n.active,
          n.upstream_node_id,
          un.node_name AS upstream_node_name,
          n.type,
          n.priority,
          n.conninfo
     FROM repmgr.nodes n
LEFT JOIN repmgr.nodes un
       ON un.node_id = n.upstream_node_id;


/* XXX update upgrade scripts! */
CREATE TABLE repmgr.voting_term (
  term INT NOT NULL
);

CREATE UNIQUE INDEX voting_term_restrict
ON repmgr.voting_term ((TRUE));

CREATE RULE voting_term_delete AS
   ON DELETE TO repmgr.voting_term
   DO INSTEAD NOTHING;


/* ================= */
/* repmgrd functions */
/* ================= */

/* monitoring functions */

CREATE FUNCTION set_local_node_id(INT)
  RETURNS VOID
  AS 'MODULE_PATHNAME', 'set_local_node_id'
  LANGUAGE C STRICT;

CREATE FUNCTION get_local_node_id()
  RETURNS INT
  AS 'MODULE_PATHNAME', 'get_local_node_id'
  LANGUAGE C STRICT;

CREATE FUNCTION standby_set_last_updated()
  RETURNS TIMESTAMP WITH TIME ZONE
  AS 'MODULE_PATHNAME', 'standby_set_last_updated'
  LANGUAGE C STRICT;

CREATE FUNCTION standby_get_last_updated()
  RETURNS TIMESTAMP WITH TIME ZONE
  AS 'MODULE_PATHNAME', 'standby_get_last_updated'
  LANGUAGE C STRICT;

/* failover functions */

CREATE FUNCTION notify_follow_primary(INT)
  RETURNS VOID
  AS 'MODULE_PATHNAME', 'notify_follow_primary'
  LANGUAGE C STRICT;

CREATE FUNCTION get_new_primary()
  RETURNS INT
  AS 'MODULE_PATHNAME', 'get_new_primary'
  LANGUAGE C STRICT;

CREATE FUNCTION reset_voting_status()
  RETURNS VOID
  AS 'MODULE_PATHNAME', 'reset_voting_status'
  LANGUAGE C STRICT;

CREATE FUNCTION am_bdr_failover_handler(INT)
  RETURNS BOOL
  AS 'MODULE_PATHNAME', 'am_bdr_failover_handler'
  LANGUAGE C STRICT;

CREATE FUNCTION unset_bdr_failover_handler()
  RETURNS VOID
  AS 'MODULE_PATHNAME', 'unset_bdr_failover_handler'
  LANGUAGE C STRICT;


CREATE VIEW repmgr.replication_status AS
  SELECT m.primary_node_id, m.standby_node_id, n.node_name AS standby_name,
 	     n.type AS node_type, n.active, last_monitor_time,
         CASE WHEN n.type='standby' THEN m.last_wal_primary_location ELSE NULL END AS last_wal_primary_location,
         m.last_wal_standby_location,
         CASE WHEN n.type='standby' THEN pg_catalog.pg_size_pretty(m.replication_lag) ELSE NULL END AS replication_lag,
         CASE WHEN n.type='standby' THEN
           CASE WHEN replication_lag > 0 THEN age(now(), m.last_apply_time) ELSE '0'::INTERVAL END
           ELSE NULL
         END AS replication_time_lag,
         CASE WHEN n.type='standby' THEN pg_catalog.pg_size_pretty(m.apply_lag) ELSE NULL END AS apply_lag,
         AGE(NOW(), CASE WHEN pg_catalog.pg_is_in_recovery() THEN repmgr.standby_get_last_updated() ELSE m.last_monitor_time END) AS communication_time_lag
    FROM repmgr.monitoring_history m
    JOIN repmgr.nodes n ON m.standby_node_id = n.node_id
   WHERE (m.standby_node_id, m.last_monitor_time) IN (
	          SELECT m1.standby_node_id, MAX(m1.last_monitor_time)
			    FROM repmgr.monitoring_history m1 GROUP BY 1
         );