#!/bin/bash
# Database backup script for ciyuan_viewfinder
# Usage: ./scripts/backup_db.sh
# Recommended: add to crontab for daily backups
# Example crontab: 0 3 * * * /path/to/server/scripts/backup_db.sh

set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
SERVER_DIR="$(dirname "$SCRIPT_DIR")"

# Load .env
if [ -f "$SERVER_DIR/.env" ]; then
  export $(grep -v '^#' "$SERVER_DIR/.env" | xargs)
fi

DB_HOST="${DB_HOST:-10.0.10.11}"
DB_PORT="${DB_PORT:-5432}"
DB_NAME="${DB_NAME:-ciyuan_viewfinder}"
DB_USER="${DB_USER:-shiran}"

BACKUP_DIR="${BACKUP_DIR:-$SERVER_DIR/backups}"
RETENTION_DAYS="${RETENTION_DAYS:-30}"

mkdir -p "$BACKUP_DIR"

TIMESTAMP=$(date +%Y%m%d_%H%M%S)
BACKUP_FILE="$BACKUP_DIR/${DB_NAME}_${TIMESTAMP}.sql.gz"

echo "[$(date)] Starting backup of $DB_NAME..."

pg_dump -h "$DB_HOST" -p "$DB_PORT" -U "$DB_USER" -d "$DB_NAME" \
  --no-owner --no-acl --format=plain \
  | gzip > "$BACKUP_FILE"

echo "[$(date)] Backup saved to $BACKUP_FILE ($(du -sh "$BACKUP_FILE" | cut -f1))"

# Cleanup old backups
find "$BACKUP_DIR" -name "${DB_NAME}_*.sql.gz" -mtime +$RETENTION_DAYS -delete
echo "[$(date)] Cleaned up backups older than $RETENTION_DAYS days"

echo "[$(date)] Backup complete."