-- Functions: realtime
-- Gerado automaticamente em 2026-04-17T12:23:05.223Z
-- Total: 12

CREATE FUNCTION realtime.apply_rls(wal jsonb, max_record_bytes integer DEFAULT (1024 * 1024)) RETURNS SETOF realtime.wal_rls
    LANGUAGE plpgsql
    AS $$
declare
-- Regclass of the table e.g. public.notes
entity_ regclass = (quote_ident(wal ->> 'schema') || '.' || quote_ident(wal ->> 'table'))::regclass;

-- I, U, D, T: insert, update ...
action realtime.action = (
    case wal ->> 'action'
        when 'I' then 'INSERT'
        when 'U' then 'UPDATE'
        when 'D' then 'DELETE'
        else 'ERROR'
    end
);

-- Is row level security enabled for the table
is_rls_enabled bool = relrowsecurity from pg_class where oid = entity_;

subscriptions realtime.subscription[] = array_agg(subs)
    from
        realtime.subscription subs
    where
        subs.entity = entity_;

-- Subscription vars
roles regrole[] = array_agg(distinct us.claims_role::text)
    from
        unnest(subscriptions) us;

working_role regrole;
claimed_role regrole;
claims jsonb;

subscription_id uuid;
subscription_has_access bool;
visible_to_subscription_ids uuid[] = '{}';

-- structured info for wal's columns
columns realtime.wal_column[];
-- previous identity values for update/delete
old_columns realtime.wal_column[];

error_record_exceeds_max_size boolean = octet_length(wal::text) > max_record_bytes;

-- Primary jsonb output for record
output jsonb;

begin
perform set_config('role', null, true);

columns =
    array_agg(
        (
            x->>'name',
            x->>'type',
            x->>'typeoid',
            realtime.cast(
                (x->'value') #>> '{}',
                coalesce(
                    (x->>'typeoid')::regtype, -- null when wal2json version <= 2.4
                    (x->>'type')::regtype
                )
            ),
            (pks ->> 'name') is not null,
            true
        )::realtime.wal_column
    )
    from
        jsonb_array_elements(wal -> 'columns') x
        left join jsonb_array_elements(wal -> 'pk') pks
            on (x ->> 'name') = (pks ->> 'name');

old_columns =
    array_agg(
        (
            x->>'name',
            x->>'type',
            x->>'typeoid',
            realtime.cast(
                (x->'value') #>> '{}',
                coalesce(
                    (x->>'typeoid')::regtype, -- null when wal2json version <= 2.4
                    (x->>'type')::regtype
                )
            ),
            (pks ->> 'name') is not null,
            true
        )::realtime.wal_column
    )
    from
        jsonb_array_elements(wal -> 'identity') x
        left join jsonb_array_elements(wal -> 'pk') pks
            on (x ->> 'name') = (pks ->> 'name');

for working_role in select * from unnest(roles) loop

    -- Update `is_selectable` for columns and old_columns
    columns =
        array_agg(
            (
                c.name,
                c.type_name,
                c.type_oid,
                c.value,
                c.is_pkey,
                pg_catalog.has_column_privilege(working_role, entity_, c.name, 'SELECT')
            )::realtime.wal_column
        )
        from
            unnest(columns) c;

    old_columns =
            array_agg(
                (
                    c.name,
                    c.type_name,
                    c.type_oid,
                    c.value,
                    c.is_pkey,
                    pg_catalog.has_column_privilege(working_role, entity_, c.name, 'SELECT')
                )::realtime.wal_column
            )
            from
                unnest(old_columns) c;

    if action <> 'DELETE' and count(1) = 0 from unnest(columns) c where c.is_pkey then
        return next (
            jsonb_build_object(
                'schema', wal ->> 'schema',
                'table', wal ->> 'table',
                'type', action
            ),
            is_rls_enabled,
            -- subscriptions is already filtered by entity
            (select array_agg(s.subscription_id) from unnest(subscriptions) as s where claims_role = working_role),
            array['Error 400: Bad Request, no primary key']
        )::realtime.wal_rls;

    -- The claims role does not have SELECT permission to the primary key of entity
    elsif action <> 'DELETE' and sum(c.is_selectable::int) <> count(1) from unnest(columns) c where c.is_pkey then
        return next (
            jsonb_build_object(
                'schema', wal ->> 'schema',
                'table', wal ->> 'table',
                'type', action
            ),
            is_rls_enabled,
            (select array_agg(s.subscription_id) from unnest(subscriptions) as s where claims_role = working_role),
            array['Error 401: Unauthorized']
        )::realtime.wal_rls;

    else
        output = jsonb_build_object(
            'schema', wal ->> 'schema',
            'table', wal ->> 'table',
            'type', action,
            'commit_timestamp', to_char(
                ((wal ->> 'timestamp')::timestamptz at time zone 'utc'),
                'YYYY-MM-DD"T"HH24:MI:SS.MS"Z"'
            ),
            'columns', (
                select
                    jsonb_agg(
                        jsonb_build_object(
                            'name', pa.attname,
                            'type', pt.typname
                        )
                        order by pa.attnum asc
                    )
                from
                    pg_attribute pa
                    join pg_type pt
                        on pa.atttypid = pt.oid
                where
                    attrelid = entity_
                    and attnum > 0
                    and pg_catalog.has_column_privilege(working_role, entity_, pa.attname, 'SELECT')
            )
        )
        -- Add "record" key for insert and update
        || case
            when action in ('INSERT', 'UPDATE') then
                jsonb_build_object(
                    'record',
                    (
                        select
                            jsonb_object_agg(
                                -- if unchanged toast, get column name and value from old record
                                coalesce((c).name, (oc).name),
                                case
                                    when (c).name is null then (oc).value
                                    else (c).value
                                end
                            )
                        from
                            unnest(columns) c
                            full outer join unnest(old_columns) oc
                                on (c).name = (oc).name
                        where
                            coalesce((c).is_selectable, (oc).is_selectable)
                            and ( not error_record_exceeds_max_size or (octet_length((c).value::text) <= 64))
                    )
                )
            else '{}'::jsonb
        end
        -- Add "old_record" key for update and delete
        || case
            when action = 'UPDATE' then
                jsonb_build_object(
                        'old_record',
                        (
                            select jsonb_object_agg((c).name, (c).value)
                            from unnest(old_columns) c
                            where
                                (c).is_selectable
                                and ( not error_record_exceeds_max_size or (octet_length((c).value::text) <= 64))
                        )
                    )
            when action = 'DELETE' then
                jsonb_build_object(
                    'old_record',
                    (
                        select jsonb_object_agg((c).name, (c).value)
                        from unnest(old_columns) c
                        where
                            (c).is_selectable
                            and ( not error_record_exceeds_max_size or (octet_length((c).value::text) <= 64))
                            and ( not is_rls_enabled or (c).is_pkey ) -- if RLS enabled, we can't secure deletes so filter to pkey
                    )
                )
            else '{}'::jsonb
        end;

        -- Create the prepared statement
        if is_rls_enabled and action <> 'DELETE' then
            if (select 1 from pg_prepared_statements where name = 'walrus_rls_stmt' limit 1) > 0 then
                deallocate walrus_rls_stmt;
            end if;
            execute realtime.build_prepared_statement_sql('walrus_rls_stmt', entity_, columns);
        end if;

        visible_to_subscription_ids = '{}';

        for subscription_id, claims in (
                select
                    subs.subscription_id,
                    subs.claims
                from
                    unnest(subscriptions) subs
                where
                    subs.entity = entity_
                    and subs.claims_role = working_role
                    and (
                        realtime.is_visible_through_filters(columns, subs.filters)
                        or (
                          action = 'DELETE'
                          and realtime.is_visible_through_filters(old_columns, subs.filters)
                        )
                    )
        ) loop

            if not is_rls_enabled or action = 'DELETE' then
                visible_to_subscription_ids = visible_to_subscription_ids || subscription_id;
            else
                -- Check if RLS allows the role to see the record
                perform
                    -- Trim leading and trailing quotes from working_role because set_config
                    -- doesn't recognize the role as valid if they are included
                    set_config('role', trim(both '"' from working_role::text), true),
                    set_config('request.jwt.claims', claims::text, true);

                execute 'execute walrus_rls_stmt' into subscription_has_access;

                if subscription_has_access then
                    visible_to_subscription_ids = visible_to_subscription_ids || subscription_id;
                end if;
            end if;
        end loop;

        perform set_config('role', null, true);

        return next (
            output,
            is_rls_enabled,
            visible_to_subscription_ids,
            case
                when error_record_exceeds_max_size then array['Error 413: Payload Too Large']
                else '{}'
            end
        )::realtime.wal_rls;

    end if;
end loop;

perform set_config('role', null, true);
end;
$$;

CREATE FUNCTION realtime.broadcast_changes(topic_name text, event_name text, operation text, table_name text, table_schema text, new record, old record, level text DEFAULT 'ROW'::text) RETURNS void
    LANGUAGE plpgsql
    AS $$
DECLARE
    -- Declare a variable to hold the JSONB representation of the row
    row_data jsonb := '{}'::jsonb;
BEGIN
    IF level = 'STATEMENT' THEN
        RAISE EXCEPTION 'function can only be triggered for each row, not for each statement';
    END IF;
    -- Check the operation type and handle accordingly
    IF operation = 'INSERT' OR operation = 'UPDATE' OR operation = 'DELETE' THEN
        row_data := jsonb_build_object('old_record', OLD, 'record', NEW, 'operation', operation, 'table', table_name, 'schema', table_schema);
        PERFORM realtime.send (row_data, event_name, topic_name);
    ELSE
        RAISE EXCEPTION 'Unexpected operation type: %', operation;
    END IF;
EXCEPTION
    WHEN OTHERS THEN
        RAISE EXCEPTION 'Failed to process the row: %', SQLERRM;
END;

$$;

CREATE FUNCTION realtime.build_prepared_statement_sql(prepared_statement_name text, entity regclass, columns realtime.wal_column[]) RETURNS text
    LANGUAGE sql
    AS $$
      /*
      Builds a sql string that, if executed, creates a prepared statement to
      tests retrive a row from *entity* by its primary key columns.
      Example
          select realtime.build_prepared_statement_sql('public.notes', '{"id"}'::text[], '{"bigint"}'::text[])
      */
          select
      'prepare ' || prepared_statement_name || ' as
          select
              exists(
                  select
                      1
                  from
                      ' || entity || '
                  where
                      ' || string_agg(quote_ident(pkc.name) || '=' || quote_nullable(pkc.value #>> '{}') , ' and ') || '
              )'
          from
              unnest(columns) pkc
          where
              pkc.is_pkey
          group by
              entity
      $$;

CREATE FUNCTION realtime."cast"(val text, type_ regtype) RETURNS jsonb
    LANGUAGE plpgsql IMMUTABLE
    AS $$
    declare
      res jsonb;
    begin
      execute format('select to_jsonb(%L::'|| type_::text || ')', val)  into res;
      return res;
    end
    $$;

CREATE FUNCTION realtime.check_equality_op(op realtime.equality_op, type_ regtype, val_1 text, val_2 text) RETURNS boolean
    LANGUAGE plpgsql IMMUTABLE
    AS $$
      /*
      Casts *val_1* and *val_2* as type *type_* and check the *op* condition for truthiness
      */
      declare
          op_symbol text = (
              case
                  when op = 'eq' then '='
                  when op = 'neq' then '!='
                  when op = 'lt' then '<'
                  when op = 'lte' then '<='
                  when op = 'gt' then '>'
                  when op = 'gte' then '>='
                  when op = 'in' then '= any'
                  else 'UNKNOWN OP'
              end
          );
          res boolean;
      begin
          execute format(
              'select %L::'|| type_::text || ' ' || op_symbol
              || ' ( %L::'
              || (
                  case
                      when op = 'in' then type_::text || '[]'
                      else type_::text end
              )
              || ')', val_1, val_2) into res;
          return res;
      end;
      $$;

CREATE FUNCTION realtime.is_visible_through_filters(columns realtime.wal_column[], filters realtime.user_defined_filter[]) RETURNS boolean
    LANGUAGE sql IMMUTABLE
    AS $_$
    /*
    Should the record be visible (true) or filtered out (false) after *filters* are applied
    */
        select
            -- Default to allowed when no filters present
            $2 is null -- no filters. this should not happen because subscriptions has a default
            or array_length($2, 1) is null -- array length of an empty array is null
            or bool_and(
                coalesce(
                    realtime.check_equality_op(
                        op:=f.op,
                        type_:=coalesce(
                            col.type_oid::regtype, -- null when wal2json version <= 2.4
                            col.type_name::regtype
                        ),
                        -- cast jsonb to text
                        val_1:=col.value #>> '{}',
                        val_2:=f.value
                    ),
                    false -- if null, filter does not match
                )
            )
        from
            unnest(filters) f
            join unnest(columns) col
                on f.column_name = col.name;
    $_$;

CREATE FUNCTION realtime.list_changes(publication name, slot_name name, max_changes integer, max_record_bytes integer) RETURNS SETOF realtime.wal_rls
    LANGUAGE sql
    SET log_min_messages TO 'fatal'
    AS $$
      with pub as (
        select
          concat_ws(
            ',',
            case when bool_or(pubinsert) then 'insert' else null end,
            case when bool_or(pubupdate) then 'update' else null end,
            case when bool_or(pubdelete) then 'delete' else null end
          ) as w2j_actions,
          coalesce(
            string_agg(
              realtime.quote_wal2json(format('%I.%I', schemaname, tablename)::regclass),
              ','
            ) filter (where ppt.tablename is not null and ppt.tablename not like '% %'),
            ''
          ) w2j_add_tables
        from
          pg_publication pp
          left join pg_publication_tables ppt
            on pp.pubname = ppt.pubname
        where
          pp.pubname = publication
        group by
          pp.pubname
        limit 1
      ),
      w2j as (
        select
          x.*, pub.w2j_add_tables
        from
          pub,
          pg_logical_slot_get_changes(
            slot_name, null, max_changes,
            'include-pk', 'true',
            'include-transaction', 'false',
            'include-timestamp', 'true',
            'include-type-oids', 'true',
            'format-version', '2',
            'actions', pub.w2j_actions,
            'add-tables', pub.w2j_add_tables
          ) x
      )
      select
        xyz.wal,
        xyz.is_rls_enabled,
        xyz.subscription_ids,
        xyz.errors
      from
        w2j,
        realtime.apply_rls(
          wal := w2j.data::jsonb,
          max_record_bytes := max_record_bytes
        ) xyz(wal, is_rls_enabled, subscription_ids, errors)
      where
        w2j.w2j_add_tables <> ''
        and xyz.subscription_ids[1] is not null
    $$;

CREATE FUNCTION realtime.quote_wal2json(entity regclass) RETURNS text
    LANGUAGE sql IMMUTABLE STRICT
    AS $$
      select
        (
          select string_agg('' || ch,'')
          from unnest(string_to_array(nsp.nspname::text, null)) with ordinality x(ch, idx)
          where
            not (x.idx = 1 and x.ch = '"')
            and not (
              x.idx = array_length(string_to_array(nsp.nspname::text, null), 1)
              and x.ch = '"'
            )
        )
        || '.'
        || (
          select string_agg('' || ch,'')
          from unnest(string_to_array(pc.relname::text, null)) with ordinality x(ch, idx)
          where
            not (x.idx = 1 and x.ch = '"')
            and not (
              x.idx = array_length(string_to_array(nsp.nspname::text, null), 1)
              and x.ch = '"'
            )
          )
      from
        pg_class pc
        join pg_namespace nsp
          on pc.relnamespace = nsp.oid
      where
        pc.oid = entity
    $$;

CREATE FUNCTION realtime.send(payload jsonb, event text, topic text, private boolean DEFAULT true) RETURNS void
    LANGUAGE plpgsql
    AS $$
DECLARE
  generated_id uuid;
  final_payload jsonb;
BEGIN
  BEGIN
    -- Generate a new UUID for the id
    generated_id := gen_random_uuid();

    -- Check if payload has an 'id' key, if not, add the generated UUID
    IF payload ? 'id' THEN
      final_payload := payload;
    ELSE
      final_payload := jsonb_set(payload, '{id}', to_jsonb(generated_id));
    END IF;

    -- Set the topic configuration
    EXECUTE format('SET LOCAL realtime.topic TO %L', topic);

    -- Attempt to insert the message
    INSERT INTO realtime.messages (id, payload, event, topic, private, extension)
    VALUES (generated_id, final_payload, event, topic, private, 'broadcast');
  EXCEPTION
    WHEN OTHERS THEN
      -- Capture and notify the error
      RAISE WARNING 'ErrorSendingBroadcastMessage: %', SQLERRM;
  END;
END;
$$;

CREATE FUNCTION realtime.subscription_check_filters() RETURNS trigger
    LANGUAGE plpgsql
    AS $$
    /*
    Validates that the user defined filters for a subscription:
    - refer to valid columns that the claimed role may access
    - values are coercable to the correct column type
    */
    declare
        col_names text[] = coalesce(
                array_agg(c.column_name order by c.ordinal_position),
                '{}'::text[]
            )
            from
                information_schema.columns c
            where
                format('%I.%I', c.table_schema, c.table_name)::regclass = new.entity
                and pg_catalog.has_column_privilege(
                    (new.claims ->> 'role'),
                    format('%I.%I', c.table_schema, c.table_name)::regclass,
                    c.column_name,
                    'SELECT'
                );
        filter realtime.user_defined_filter;
        col_type regtype;

        in_val jsonb;
    begin
        for filter in select * from unnest(new.filters) loop
            -- Filtered column is valid
            if not filter.column_name = any(col_names) then
                raise exception 'invalid column for filter %', filter.column_name;
            end if;

            -- Type is sanitized and safe for string interpolation
            col_type = (
                select atttypid::regtype
                from pg_catalog.pg_attribute
                where attrelid = new.entity
                      and attname = filter.column_name
            );
            if col_type is null then
                raise exception 'failed to lookup type for column %', filter.column_name;
            end if;

            -- Set maximum number of entries for in filter
            if filter.op = 'in'::realtime.equality_op then
                in_val = realtime.cast(filter.value, (col_type::text || '[]')::regtype);
                if coalesce(jsonb_array_length(in_val), 0) > 100 then
                    raise exception 'too many values for `in` filter. Maximum 100';
                end if;
            else
                -- raises an exception if value is not coercable to type
                perform realtime.cast(filter.value, col_type);
            end if;

        end loop;

        -- Apply consistent order to filters so the unique constraint on
        -- (subscription_id, entity, filters) can't be tricked by a different filter order
        new.filters = coalesce(
            array_agg(f order by f.column_name, f.op, f.value),
            '{}'
        ) from unnest(new.filters) f;

        return new;
    end;
    $$;

CREATE FUNCTION realtime.to_regrole(role_name text) RETURNS regrole
    LANGUAGE sql IMMUTABLE
    AS $$ select role_name::regrole $$;

CREATE FUNCTION realtime.topic() RETURNS text
    LANGUAGE sql STABLE
    AS $$
select nullif(current_setting('realtime.topic', true), '')::text;
$$;
