#!/bin/bash

# --- CONFIGURATION ---
# The bucket quotas check requires the 'mc' (MinIO client) command.
# Download it from https://min.io/docs/minio/linux/reference/minio-client/mc.html
# and make sure it's in your PATH.

# MinIO Server Details
MINIO_ALIAS="minio-k0s"
MINIO_URL="http://192.168.153.245:9000"
MINIO_ACCESS_KEY="Tg4UTucrnhJ8FPaPsqra"
MINIO_SECRET_KEY="mGEJ6CSYWfSYdaQ90yAY2hfvNtMXV6at9T34o3Kc"

# Restic Backup Details
RESTIC_REPO="s3:http://192.168.153.245:9000/backup"
BACKUP_SOURCE="/home/$(whoami)"
RESTIC_EXCLUDE_FILE="~/.resticignore" # optional, create this file to list folders/files to exclude

# Restic Environment Variables (for security, use these instead of passing keys directly in the command)
export RESTIC_PASSWORD="frack666"
export AWS_ACCESS_KEY_ID="${MINIO_ACCESS_KEY}"
export AWS_SECRET_ACCESS_KEY="${MINIO_SECRET_KEY}"

# Quota Check Configuration
BUCKET_NAME="backup"
MIN_QUOTA_REQUIRED_MB=1024 # Minimum required space in megabytes (1GB)

# Notification System Configuration
# EMAIL_RECIPIENT="william.valentin.info@gmail.com"
# EMAIL_SUBJECT="Restic Backup Report"

# --- FUNCTIONS ---
send_notification() {
    local type="$1"
    local message="$2"
    local summary="Restic Backup Report"

    # Send GNOME notification
    if command -v notify-send &> /dev/null; then
        notify-send -t 5000 -i "dialog-${type}" "${summary}" "${message}"
    fi

    # Send email notification
    if [ -n "${EMAIL_RECIPIENT}" ]; then
        echo -e "${message}" | mail -s "${summary} - ${type^^}" "${EMAIL_RECIPIENT}"
    fi
}

# --- SCRIPT START ---
echo "Starting Restic backup process for user folder..."
echo "------------------------------------------------"

# --- 1. MinIO Client Setup & Quota Check ---
# Check if MinIO client (mc) is installed
if ! command -v mc &> /dev/null; then
    send_notification "error" "MinIO client 'mc' not found. Please install it to use the quota check."
    exit 1
fi

# Set up MinIO alias if it doesn't exist
if ! mc alias list | grep -q "${MINIO_ALIAS}"; then
    echo "Setting up MinIO alias '${MINIO_ALIAS}'..."
    mc alias set "${MINIO_ALIAS}" "${MINIO_URL}" "${MINIO_ACCESS_KEY}" "${MINIO_SECRET_KEY}"
    if [ $? -ne 0 ]; then
        send_notification "error" "Failed to set up MinIO alias. Check your credentials and URL."
        exit 1
    fi
fi

# Get bucket usage and quota
BUCKET_USAGE_MB=$(mc du "${MINIO_ALIAS}/${BUCKET_NAME}" | awk '{print $1}')
BUCKET_QUOTA_MB=$(mc quota info "${MINIO_ALIAS}/${BUCKET_NAME}" | grep 'Hard Quota' | awk '{print $3}' | sed 's/MB//')

if [ -z "${BUCKET_QUOTA_MB}" ]; then
    echo "NOTICE: No hard quota set for bucket '${BUCKET_NAME}'. Skipping quota check."
else
    # Calculate remaining space
    REMAINING_SPACE_MB=$((BUCKET_QUOTA_MB - BUCKET_USAGE_MB))

    echo "Bucket '${BUCKET_NAME}' usage: ${BUCKET_USAGE_MB} MB"
    echo "Bucket '${BUCKET_NAME}' quota: ${BUCKET_QUOTA_MB} MB"
    echo "Remaining space: ${REMAINING_SPACE_MB} MB"

    if [ "${REMAINING_SPACE_MB}" -lt "${MIN_QUOTA_REQUIRED_MB}" ]; then
        send_notification "error" "Insufficient space in the bucket. Only ${REMAINING_SPACE_MB} MB remaining, but ${MIN_QUOTA_REQUIRED_MB} MB required."
        exit 1
    fi
fi

# --- 2. Restic Repository Check ---
echo "Checking Restic repository existence..."
if ! restic snapshots --json &> /dev/null; then
    echo "Restic repository not found. Initializing a new one..."
    restic init
    if [ $? -ne 0 ]; then
        send_notification "error" "Failed to initialize Restic repository. Check your RESTIC_REPO and credentials."
        exit 1
    fi
fi

# --- 3. Backup Execution ---
echo "Starting backup of ${BACKUP_SOURCE}..."

if [ -f "${RESTIC_EXCLUDE_FILE}" ]; then
    echo "Excluding files listed in ${RESTIC_EXCLUDE_FILE}..."
    restic backup "${BACKUP_SOURCE}" --exclude-file="${RESTIC_EXCLUDE_FILE}"
else
    echo "No exclude file found, backing up all files in the source directory."
    restic backup "${BACKUP_SOURCE}"
fi

if [ $? -ne 0 ]; then
    send_notification "error" "Restic backup failed."
    exit 1
else
    send_notification "info" "Restic backup completed successfully."
fi

# --- 4. Cleanup and Maintenance ---
echo "Running repository maintenance..."
restic forget --prune --keep-daily 7 --keep-weekly 4 --keep-monthly 6

if [ $? -ne 0 ]; then
    send_notification "warning" "Restic maintenance failed. Check the logs for details."
fi

echo "Backup script finished. ✨"