#!/bin/bash
# Seafile restore — companion to backup.sh (kb#192).
#
# Restores a snapshot produced by backup.sh (ccnet_db.sql, seafile_db.sql,
# seahub_db.sql, and a data/ directory tree) into a running MariaDB
# container plus a data directory. Defaults to the live containers/paths,
# but every target is overridable via env vars so the same script can be
# pointed at throwaway containers + a scratch data dir for a dry-run
# restore test.
#
# Usage:
#   ./restore.sh /mnt/backups/seafile/<snapshot-dir>
#
# Env overrides (defaults = live service):
#   MYSQL_CONTAINER=seafile-mysql
#   SEAFILE_CONTAINER=seafile        # stopped/started around the data-dir copy; set to "" to skip
#   DATA_DIR=/mnt/misc/seafile       # host path the seafile-net containers bind-mount
#   MYSQL_USER=seafile
#   MYSQL_PASSWORD=<from agap_git/seafile/.env SEAFILE_MYSQL_DB_PASSWORD, falls back to backup.sh's literal>
#
# WARNING: this drops and reloads the target's live ccnet/seafile/seahub
# databases and overwrites its data directory. Never run against the live
# "seafile-mysql"/"seafile" containers or /mnt/misc/seafile unless you
# intend a real disaster recovery — for testing, point the *_CONTAINER
# and DATA_DIR vars at throwaway equivalents instead.
#
# NOTE: restoring only the three databases (no data/ directory, e.g.
# MYSQL_CONTAINER set but SEAFILE_CONTAINER="" and no data/ present in the
# snapshot) is a valid partial restore for verifying DB integrity —
# the script skips the data-dir step automatically if snapshot has no data/.

set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
[ -f "$SCRIPT_DIR/.env" ] && source "$SCRIPT_DIR/.env"

MYSQL_CONTAINER="${MYSQL_CONTAINER:-seafile-mysql}"
# NOTE: use ${VAR-default} (no colon) for SEAFILE_CONTAINER so that an
# explicit empty string (SEAFILE_CONTAINER="") disables the data-dir step,
# as documented above — ${VAR:-default} would treat "" as unset and fall
# back to the live container name, which is not what an operator asking
# to skip that step intends.
SEAFILE_CONTAINER="${SEAFILE_CONTAINER-seafile}"
DATA_DIR="${DATA_DIR:-/mnt/misc/seafile}"
MYSQL_USER="${MYSQL_USER:-seafile}"
MYSQL_PASSWORD="${MYSQL_PASSWORD:-${SEAFILE_MYSQL_DB_PASSWORD:-FWsYYeZa15ro6x}}"

if [ $# -lt 1 ]; then
  echo "Usage: $0 <path-to-backup-snapshot-dir>" >&2
  echo "  e.g. $0 /mnt/backups/seafile/20260728-0200" >&2
  exit 1
fi

SRC="$(realpath "$1")"

for DB in ccnet_db seafile_db seahub_db; do
  if [ ! -s "$SRC/${DB}.sql" ]; then
    echo "Error: $SRC/${DB}.sql is missing or empty — refusing to restore from a broken snapshot" >&2
    exit 1
  fi
done

if ! docker inspect "$MYSQL_CONTAINER" > /dev/null 2>&1; then
  echo "Error: mysql container '$MYSQL_CONTAINER' does not exist" >&2
  exit 1
fi

echo "Restoring databases into '$MYSQL_CONTAINER' from $SRC"

for DB in ccnet_db seafile_db seahub_db; do
  echo "Restoring $DB..."
  docker exec -i "$MYSQL_CONTAINER" mysql -u "$MYSQL_USER" -p"$MYSQL_PASSWORD" \
    -e "DROP DATABASE IF EXISTS \`$DB\`; CREATE DATABASE \`$DB\` CHARACTER SET utf8mb4;"
  docker exec -i "$MYSQL_CONTAINER" mysql -u "$MYSQL_USER" -p"$MYSQL_PASSWORD" "$DB" < "$SRC/${DB}.sql"
  echo "Restored: $DB"
done

echo "Verifying restored databases..."
for DB in ccnet_db seafile_db seahub_db; do
  TABLES=$(docker exec "$MYSQL_CONTAINER" mysql -u "$MYSQL_USER" -p"$MYSQL_PASSWORD" -N -e "SHOW TABLES FROM \`$DB\`;" | wc -l)
  echo "$DB: $TABLES tables"
done

if [ -d "$SRC/data" ] && [ -n "$SEAFILE_CONTAINER" ]; then
  echo "Restoring data directory into $DATA_DIR..."
  if docker inspect "$SEAFILE_CONTAINER" > /dev/null 2>&1; then
    docker stop "$SEAFILE_CONTAINER" > /dev/null
  fi
  rsync -a --delete \
    --exclude='seafile-mysql/' \
    --exclude='seafile-caddy/' \
    "$SRC/data/" "$DATA_DIR/"
  if docker inspect "$SEAFILE_CONTAINER" > /dev/null 2>&1; then
    docker start "$SEAFILE_CONTAINER" > /dev/null
  fi
else
  echo "Note: no data/ dir in snapshot or SEAFILE_CONTAINER unset — skipping data-dir restore (DB-only restore)"
fi

echo "Restore complete."