#!/bin/bash
# PostgreSQL Restore Script for Proxmox LXC Container

# Check if backup file is provided
if [ $# -ne 1 ]; then
    echo "Usage: $0 <backup-file>"
    echo "Example: $0 ../backups/postgres_backup_20250419_120000.sql.gz"
    echo "         $0 ../backups/postgres_volume_backup_20250419_120000.tar.gz"
    exit 1
fi

BACKUP_FILE=$1

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

# Load environment variables
if [ -f ../.env ]; then
    source ../.env
else
    echo "Error: .env file not found!"
    exit 1
fi

# Set default values if not provided in .env
POSTGRES_USER=${POSTGRES_USER:-"postgres"}
POSTGRES_DB=${POSTGRES_DB:-"postgres"}

echo "Starting PostgreSQL restore..."
echo "Database: ${POSTGRES_DB}"
echo "Backup file: ${BACKUP_FILE}"

# Determine backup type (SQL dump or volume backup)
if [[ "${BACKUP_FILE}" == *"postgres_backup_"* ]]; then
    # SQL dump restore
    # Confirm restore operation
    read -p "Warning: This will overwrite the existing database. Continue? (y/n): " -n 1 -r
    echo
    if [[ ! $REPLY =~ ^[Yy]$ ]]; then
        echo "Restore operation cancelled."
        exit 0
    fi

    # Perform the restore
    echo "Restoring database from SQL dump..."
    gunzip -c ${BACKUP_FILE} | docker exec -i postgres psql -U ${POSTGRES_USER} -d ${POSTGRES_DB}

    # Check if restore was successful
    if [ $? -eq 0 ]; then
        echo "Restore completed successfully from: ${BACKUP_FILE}"
    else
        echo "Error: Restore failed!"
        exit 1
    fi
elif [[ "${BACKUP_FILE}" == *"postgres_volume_backup_"* ]]; then
    # Volume backup restore
    # Confirm restore operation
    read -p "WARNING: This will completely replace the PostgreSQL data volume. All current data will be lost. Continue? (y/n): " -n 1 -r
    echo
    if [[ ! $REPLY =~ ^[Yy]$ ]]; then
        echo "Restore operation cancelled."
        exit 0
    fi

    echo "Stopping PostgreSQL container..."
    docker-compose down

    echo "Restoring volume data from backup..."
    # Create a temporary container to restore the volume
    docker run --rm -v postgres_data:/data -v $(pwd)/$(dirname ${BACKUP_FILE}):/backup alpine sh -c "rm -rf /data/* && tar -xzf /backup/$(basename ${BACKUP_FILE}) -C / --strip-components=1"

    # Check if restore was successful
    if [ $? -eq 0 ]; then
        echo "Volume restore completed successfully from: ${BACKUP_FILE}"
        echo "Starting PostgreSQL container..."
        docker-compose up -d
        echo "Waiting for PostgreSQL to start..."
        sleep 10
        echo "PostgreSQL service restored and running."
    else
        echo "Error: Volume restore failed!"
        echo "Starting PostgreSQL container..."
        docker-compose up -d
        exit 1
    fi
else
    echo "Error: Unknown backup file format. Expected postgres_backup_*.sql.gz or postgres_volume_backup_*.tar.gz"
    exit 1
fi

exit 0