#!/bin/bash

# Atlas CMMS Database Restore Script
# This script restores a backup of the Atlas CMMS PostgreSQL database

# Check if backup file is provided
if [ $# -eq 0 ]; then
    echo "Usage: $0 <backup_file>"
    echo "Example: $0 ./backups/atlas_backup_20240101_120000.sql.gz"
    exit 1
fi

BACKUP_FILE="$1"
CONTAINER_NAME="atlas_db"
DB_NAME="atlas"
DB_USER="rootUser"

echo "Starting Atlas CMMS database restore..."
echo "Container: ${CONTAINER_NAME}"
echo "Database: ${DB_NAME}"
echo "Backup file: ${BACKUP_FILE}"

# Check if backup file exists
if [ ! -f "${BACKUP_FILE}" ]; then
    echo "Error: Backup file '${BACKUP_FILE}' not found"
    exit 1
fi

# Check if container is running
if ! docker ps | grep -q "${CONTAINER_NAME}"; then
    echo "Error: PostgreSQL container '${CONTAINER_NAME}' is not running"
    exit 1
fi

# Warning message
echo "WARNING: This will replace all data in the '${DB_NAME}' database!"
read -p "Are you sure you want to continue? (y/N): " -n 1 -r
echo
if [[ ! $REPLY =~ ^[Yy]$ ]]; then
    echo "Restore cancelled"
    exit 0
fi

# Stop the API container to prevent connections during restore
echo "Stopping API container..."
docker stop atlas_api 2>/dev/null || true

# Determine if backup file is compressed
if [[ "${BACKUP_FILE}" == *.gz ]]; then
    echo "Decompressing and restoring backup..."
    gunzip -c "${BACKUP_FILE}" | docker exec -i "${CONTAINER_NAME}" psql \
        -U "${DB_USER}" \
        -d postgres \
        --quiet
else
    echo "Restoring backup..."
    cat "${BACKUP_FILE}" | docker exec -i "${CONTAINER_NAME}" psql \
        -U "${DB_USER}" \
        -d postgres \
        --quiet
fi

# Check if restore was successful
if [ $? -eq 0 ]; then
    echo "Database restore completed successfully"
    
    # Restart the API container
    echo "Restarting API container..."
    docker start atlas_api
    
    echo "Restore process completed"
else
    echo "Error: Database restore failed"
    
    # Try to restart the API container anyway
    docker start atlas_api 2>/dev/null || true
    exit 1
fi