#!/usr/bin/env bash
set -eo pipefail

if [ "$EUID" -ne 0 ]; then
    echo "Error: This script must be run as root" >&2
    exit 1
fi

UPGRADE_TO=${1:-12}
UPGRADE_FROM=$(crudini --get /etc/zulip/zulip.conf postgresql version)
ZULIP_PATH="$(dirname "$0")/../.."

if [ "$UPGRADE_TO" = "$UPGRADE_FROM" ]; then
    echo "Already running PostgreSQL $UPGRADE_TO!"
    exit 1
fi

set -x

"$ZULIP_PATH"/scripts/lib/setup-apt-repo
apt-get install -y "postgresql-$UPGRADE_TO"
if pg_lsclusters -h | grep -qE "^$UPGRADE_TO\s+main\b"; then
    pg_dropcluster "$UPGRADE_TO" main --stop
fi

(
    # Two-stage application of Puppet; we apply the bare-bones
    # PostgreSQL configuration first, so that FTS will be configured
    # prior to the pg_upgradecluster.
    TEMP_CONF_DIR=$(mktemp -d)
    cp /etc/zulip/zulip.conf "$TEMP_CONF_DIR"
    ZULIP_CONF="${TEMP_CONF_DIR}/zulip.conf"
    crudini --set "$ZULIP_CONF" postgresql version "$UPGRADE_TO"
    crudini --set "$ZULIP_CONF" machine puppet_classes zulip::profile::base,zulip::postgresql_base
    touch "/usr/share/postgresql/$UPGRADE_TO/pgroonga_setup.sql.applied"

    "$ZULIP_PATH"/scripts/zulip-puppet-apply -f --config "$ZULIP_CONF"
    rm -rf "$TEMP_CONF_DIR"
)

# Capture the output so we know where the path to the post-upgrade scripts is
UPGRADE_LOG=$(mktemp "/var/log/zulip/postgres-upgrade-$UPGRADE_FROM-$UPGRADE_TO.XXXXXXXXX.log")
pg_upgradecluster -v "$UPGRADE_TO" "$UPGRADE_FROM" main --method=upgrade --link | tee "$UPGRADE_LOG"
SCRIPTS_PATH=$(grep -o "/var/log/postgresql/pg_upgradecluster-$UPGRADE_FROM-$UPGRADE_TO-main.*" "$UPGRADE_LOG" || true)

# If the upgrade completed successfully, lock in the new version in
# our configuration immediately
crudini --set /etc/zulip/zulip.conf postgresql version "$UPGRADE_TO"

# Update the statistics
[ -n "$SCRIPTS_PATH" ] && su postgres -c "$SCRIPTS_PATH/analyze_new_cluster.sh"

# Start the database up cleanly
"$ZULIP_PATH"/scripts/zulip-puppet-apply -f

# Drop the old data, binaries, and scripts
pg_dropcluster "$UPGRADE_FROM" main
apt remove -y "postgresql-$UPGRADE_FROM"
if [ -n "$SCRIPTS_PATH" ]; then
    su postgres -c "$SCRIPTS_PATH/delete_old_cluster.sh"
    rm -rf "$SCRIPTS_PATH"
else
    set +x
    echo
    echo
    echo ">>>>> pg_upgradecluster succeeded, but post-upgrade scripts path could not"
    echo "      be parsed out!  Please read the pg_upgradecluster output to understand"
    echo "      the current status of your cluster:"
    echo "          $UPGRADE_LOG"
    echo "      and report this bug with the Postgres $UPGRADE_FROM -> $UPGRADE_TO upgrade to:"
    echo "          https://github.com/zulip/zulip/issues"
    echo
    echo
fi