#!/bin/bash

# ==============================================================================
# Script: vaultwarden_backup.sh
# Description: Backs up Vaultwarden (SQLite DB, RSA keys, attachments, 
#              sends, and config) to a mounted drive using Vaultwarden's 
#              native backup command via Docker exec and rsync.
# Usage:       sudo ./vaultwarden_backup.sh
# Notes:       Must be run with root/sudo privileges to access Docker socket
#              and host directories.
# ==============================================================================

# ==============================================================================
# Define Variables for Source and Destination
# ==============================================================================
BACKUP_MOUNT_POINT="/mnt/5TB-Disk1"
BACKUP_DESTINATION="$BACKUP_MOUNT_POINT/backup"

# Vaultwarden settings
CONTAINER_NAME="vaultwarden"
VAULTWARDEN_DATA_DIR="/srv/docker/vaultwarden/data"
VAULTWARDEN_DESTINATION="$BACKUP_MOUNT_POINT/backup/services/vaultwarden"

# ntfy Notification Configuration
NTFY_TOPIC="Server"
NTFY_SERVER="https://ntfy.speerfam.net"
NTFY_TOKEN="tk_3xo9mejjtgemyowzckqw2souo3mux"

# ==============================================================================
# Pre-flight Checks
# ==============================================================================

# Check if the mount point directory exists and is a mounted filesystem.
if ! mountpoint -q "$BACKUP_MOUNT_POINT"; then
    echo "Error: '$BACKUP_MOUNT_POINT' is not a mount point. Please ensure the drive is mounted." >&2
    curl -H "Authorization: Bearer $NTFY_TOKEN" -d "Error: Script failed. Destination '$BACKUP_MOUNT_POINT' is not mounted." "$NTFY_SERVER/$NTFY_TOPIC" > /dev/null 2>&1
    exit 1
fi

# Check if the Vaultwarden source directory exists on the host.
if [ ! -d "$VAULTWARDEN_DATA_DIR" ]; then
    echo "Error: Vaultwarden source directory '$VAULTWARDEN_DATA_DIR' not found." >&2
    curl -H "Authorization: Bearer $NTFY_TOKEN" -d "Error: Script failed. Vaultwarden data directory '$VAULTWARDEN_DATA_DIR' not found." "$NTFY_SERVER/$NTFY_TOPIC" > /dev/null 2>&1
    exit 1
fi

# Check if the Docker container is running.
if ! docker ps --format '{{.Names}}' | grep -q "^${CONTAINER_NAME}$"; then
    echo "Error: Docker container '$CONTAINER_NAME' is not running." >&2
    curl -H "Authorization: Bearer $NTFY_TOKEN" -d "Error: Script failed. Docker container '$CONTAINER_NAME' is not running." "$NTFY_SERVER/$NTFY_TOPIC" > /dev/null 2>&1
    exit 1
fi

# Ensure the destination directory exists.
mkdir -p "$VAULTWARDEN_DESTINATION"

# ==============================================================================
# Vaultwarden Backup Execution
# ==============================================================================
echo "Starting Vaultwarden backup via container exec..."

# Step 1: Trigger in-container database backup
docker exec "$CONTAINER_NAME" /vaultwarden backup
DB_STATUS=$?

if [ $DB_STATUS -ne 0 ]; then
    echo "Error: Vaultwarden docker exec backup failed with exit code $DB_STATUS." >&2
    curl -H "Authorization: Bearer $NTFY_TOKEN" -d "Error: Vaultwarden internal DB backup command failed." "$NTFY_SERVER/$NTFY_TOPIC" > /dev/null 2>&1
    exit 1
fi

# Step 2: Locate the newly generated database snapshot in the host data dir
LATEST_DB_BACKUP=$(ls -t "$VAULTWARDEN_DATA_DIR"/db_*.sqlite3 2>/dev/null | head -n 1)

if [ -z "$LATEST_DB_BACKUP" ]; then
    echo "Error: Could not locate generated db_*.sqlite3 backup file in '$VAULTWARDEN_DATA_DIR'." >&2
    curl -H "Authorization: Bearer $NTFY_TOKEN" -d "Error: Vaultwarden backup snapshot file missing after exec." "$NTFY_SERVER/$NTFY_TOPIC" > /dev/null 2>&1
    exit 1
fi

# Rsync the snapshot file to destination as db.sqlite3
echo "Rsyncing database snapshot to '$VAULTWARDEN_DESTINATION/db.sqlite3'..."
rsync -av --no-owner --no-group "$LATEST_DB_BACKUP" "$VAULTWARDEN_DESTINATION/db.sqlite3"
RSYNC_DB_STATUS=$?

if [ $RSYNC_DB_STATUS -ne 0 ]; then
    echo "Error: rsync failed to copy database snapshot file." >&2
    curl -H "Authorization: Bearer $NTFY_TOKEN" -d "Error: rsync failed during Vaultwarden DB snapshot sync." "$NTFY_SERVER/$NTFY_TOPIC" > /dev/null 2>&1
    exit 1
fi

# Remove the temporary snapshot file from host source directory
rm -f "$LATEST_DB_BACKUP"

# Step 3: Rsync remaining data (RSA keys, attachments, sends, config) excluding live db files
echo "Rsyncing attachments, RSA keys, and configuration files to '$VAULTWARDEN_DESTINATION'..."
rsync -av --no-owner --no-group --exclude='db.sqlite3*' "$VAULTWARDEN_DATA_DIR/" "$VAULTWARDEN_DESTINATION/"
RSYNC_DATA_STATUS=$?

# ==============================================================================
# Completion and Notification
# ==============================================================================
if [ $RSYNC_DATA_STATUS -eq 0 ]; then
    echo "Success: Vaultwarden database, keys, and attachments backed up to '$VAULTWARDEN_DESTINATION'."
    curl -H "Authorization: Bearer $NTFY_TOKEN" -d "Success: Vaultwarden backup completed successfully to $VAULTWARDEN_DESTINATION" "$NTFY_SERVER/$NTFY_TOPIC" > /dev/null 2>&1
else
    echo "Error: rsync failed with exit code $RSYNC_DATA_STATUS. Check directory permissions." >&2
    curl -H "Authorization: Bearer $NTFY_TOKEN" -d "Error: rsync failed during Vaultwarden data backup." "$NTFY_SERVER/$NTFY_TOPIC" > /dev/null 2>&1
    exit 1
fi