#!/bin/bash

# Generic Service Backup Script for Docker Compose services
# Location: /home/citadel/services/paperless/backup.sh
# Runs daily at 3 AM via systemd timer

set -e

# Service Configuration
SERVICE_NAME="paperless"
SERVICE_DIR="/home/citadel/services/$SERVICE_NAME"
DATA_DIR="/home/citadel/data/$SERVICE_NAME"
TEMP_BACKUP_DIR="/tmp/$SERVICE_NAME"
CONFIG_FILE="/home/citadel/backup/restic.conf"
COMPOSE_FILE="$SERVICE_DIR/docker-compose.yml"

# Logging
LOG_FILE="/var/log/$SERVICE_NAME-backup.log"
exec 1> >(tee -a "$LOG_FILE")
exec 2> >(tee -a "$LOG_FILE" >&2)

log() {
    echo "[$(date '+%Y-%m-%d %H:%M:%S')] $1"
}

cleanup() {
    log "Cleaning up temporary files..."
    rm -rf "$TEMP_BACKUP_DIR"
    
    # Ensure containers are running in case of error
    if docker compose -f "$COMPOSE_FILE" ps --services --filter "status=exited" | grep -q .; then
        log "Some containers are stopped, restarting..."
        cd "$SERVICE_DIR"
        docker compose up -d
    fi
}

# Set up cleanup on exit
trap cleanup EXIT

log "=== Starting $SERVICE_NAME Backup ==="

# Check if configuration exists
if [ ! -f "$CONFIG_FILE" ]; then
    log "ERROR: Configuration file $CONFIG_FILE not found!"
    exit 1
fi

# Source Restic configuration
source "$CONFIG_FILE"

# Create temporary backup directory
log "Creating temporary backup directory: $TEMP_BACKUP_DIR"
mkdir -p "$TEMP_BACKUP_DIR"

# Navigate to service directory
cd "$SERVICE_DIR"

# Check if compose file exists
if [ ! -f "$COMPOSE_FILE" ]; then
    log "ERROR: Docker compose file $COMPOSE_FILE not found!"
    exit 1
fi

log "Stopping $SERVICE_NAME containers..."
docker compose down

# Wait a moment for containers to fully stop
sleep 5

log "Creating PostgreSQL database dump..."
# Start only the database container for backup
docker compose up -d db

# Wait for database to be ready
sleep 10

# Get database credentials from .env
if [ -f "$SERVICE_DIR/.env" ]; then
    source "$SERVICE_DIR/.env"
else
    log "ERROR: .env file not found!"
    exit 1
fi

# Create database dump
DUMP_FILE="$TEMP_BACKUP_DIR/${SERVICE_NAME}_db_$(date +%Y%m%d_%H%M%S).sql"
log "Creating database dump: $DUMP_FILE"

docker compose exec -T db pg_dump -U "$POSTGRES_USER" -d "$POSTGRES_DB" > "$DUMP_FILE"

if [ $? -eq 0 ]; then
    log "✅ Database dump created successfully"
else
    log "❌ Database dump failed!"
    exit 1
fi

# Stop database container
docker compose down

log "Copying application data to temporary directory..."
# Copy data directories
cp -r "$DATA_DIR"/* "$TEMP_BACKUP_DIR/" 2>/dev/null || true

# Copy service configuration
cp -r "$SERVICE_DIR" "$TEMP_BACKUP_DIR/service_config"

log "Creating Restic backup..."

restic backup "$TEMP_BACKUP_DIR" \
    --tag "$SERVICE_NAME" \
    --tag "daily"

if [ $? -eq 0 ]; then
    log "✅ Restic backup completed successfully with tag: $SERVICE_NAME"
else
    log "❌ Restic backup failed!"
    exit 1
fi

log "Restarting $SERVICE_NAME containers..."
docker compose up -d

# Wait for services to be ready
sleep 15

# Check if services are running
if docker compose ps --services --filter "status=running" | grep -q "webserver"; then
    log "✅ $SERVICE_NAME containers restarted successfully"
else
    log "⚠️  Warning: Some containers may not be running properly"
fi

log "Running Restic maintenance (forget old snapshots)..."
# Keep: 7 daily, 4 weekly, 12 monthly, 2 yearly
restic forget \
    --tag "$SERVICE_NAME" \
    --keep-daily 7 \
    --keep-weekly 4 \
    --keep-monthly 12 \
    --keep-yearly 2 \
    --prune

log "=== Backup completed successfully ==="

# Show backup statistics
log "Current repository stats:"
restic stats --mode raw-data