#!/bin/sh

# Copyright (C) 2020-2023 Internet Systems Consortium, Inc. ("ISC")
#
# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.

# shellcheck disable=SC1091
# SC1091: Not following: ... was not specified as input (see shellcheck -x).

# Exit with error if commands exit with non-zero and if undefined variables are
# used.
set -eu

# shellcheck disable=SC2034
# SC2034: ... appears unused. Verify use (or export if used externally).
prefix="/usr"

# Include utilities. Use installed version if available and
# use build version if it isn't.
if test -f "${prefix}/share/kea/scripts/admin-utils.sh"; then
    . "${prefix}/share/kea/scripts/admin-utils.sh"
else
    . "/build/kea/src/kea-2.4.0/src/bin/admin/admin-utils.sh"
fi

VERSION=$(pgsql_version "$@")

if [ "$VERSION" != "6.0" ]; then
    printf 'This script upgrades 6.0 to 6.1. '
    printf 'Reported version is %s. Skipping upgrade.\n' "${VERSION}"
    exit 0
fi

psql "$@" >/dev/null <<EOF
START TRANSACTION;

-- This line starts the schema upgrade to version 6.1.

-- Fix v4 update trigger procedure
CREATE OR REPLACE FUNCTION proc_stat_lease4_update () RETURNS trigger AS \$stat_lease4_update\$
BEGIN
    IF OLD.subnet_id != NEW.subnet_id OR OLD.state != NEW.state THEN
        IF OLD.state < 2 THEN
            -- Decrement the old state count if record exists
            UPDATE lease4_stat SET leases = GREATEST(leases - 1, 0)
            WHERE subnet_id = OLD.subnet_id AND state = OLD.state;
        END IF;

        IF NEW.state < 2 THEN
            -- Increment the new state count if record exists
            UPDATE lease4_stat SET leases = leases + 1
            WHERE subnet_id = NEW.subnet_id AND state = NEW.state;

            -- Insert new state record if it does not exist
            IF NOT FOUND THEN
                INSERT INTO lease4_stat VALUES (NEW.subnet_id, NEW.state, 1);
            END IF;
        END IF;
    END IF;

    -- Return is ignored since this is an after insert
    RETURN NULL;
END;
\$stat_lease4_update\$ LANGUAGE plpgsql;

--
-- Fix the v4 delete trigger procedure
CREATE OR REPLACE FUNCTION proc_stat_lease4_delete () RETURNS trigger AS \$stat_lease4_delete\$
BEGIN
    IF OLD.state < 2 THEN
        -- Decrement the state count if record exists
        UPDATE lease4_stat SET leases = GREATEST(leases - 1, 0)
        WHERE subnet_id = OLD.subnet_id AND OLD.state = state;
    END IF;

    -- Return is ignored since this is an after insert
    RETURN NULL;
END;
\$stat_lease4_delete\$ LANGUAGE plpgsql;

--
-- Fix v6 update trigger procedure
CREATE OR REPLACE FUNCTION proc_stat_lease6_update () RETURNS trigger AS \$stat_lease6_update\$
BEGIN
    IF OLD.subnet_id != NEW.subnet_id OR
       OLD.lease_type != NEW.lease_type OR
       OLD.state != NEW.state THEN
        IF OLD.state < 2 THEN
            -- Decrement the old state count if record exists
            UPDATE lease6_stat SET leases = GREATEST(leases - 1, 0)
            WHERE subnet_id = OLD.subnet_id AND lease_type = OLD.lease_type
            AND state = OLD.state;
        END IF;

        IF NEW.state < 2 THEN
            -- Increment the new state count if record exists
            UPDATE lease6_stat SET leases = leases + 1
            WHERE subnet_id = NEW.subnet_id AND lease_type = NEW.lease_type
            AND state = NEW.state;

            -- Insert new state record if it does not exist
            IF NOT FOUND THEN
                INSERT INTO lease6_stat VALUES (NEW.subnet_id, NEW.lease_type, NEW.state, 1);
            END IF;
        END IF;
    END IF;

    -- Return is ignored since this is an after insert
    RETURN NULL;
END;
\$stat_lease6_update\$ LANGUAGE plpgsql;

--
-- Fix the v6 delete trigger procedure
CREATE OR REPLACE FUNCTION proc_stat_lease6_delete() RETURNS trigger AS \$stat_lease6_delete\$
BEGIN
    IF OLD.state < 2 THEN
        -- Decrement the state count if record exists
        UPDATE lease6_stat SET leases = GREATEST(leases - 1, 0)
        WHERE subnet_id = OLD.subnet_id AND lease_type = OLD.lease_type
        AND OLD.state = state;
    END IF;

    -- Return is ignored since this is an after insert
    RETURN NULL;
END;
\$stat_lease6_delete\$ LANGUAGE plpgsql;

-- Update the schema version number.
UPDATE schema_version
    SET version = '6', minor = '1';

-- This line concludes the schema upgrade to version 6.1.

-- Commit the script transaction.
COMMIT;

EOF
