#!/usr/bin/env bash
set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
COMPOSE_FILE="docker-compose-multitenant.yml"

# Directories
INVOICE_ARCHIVE_DIR="${INVOICE_ARCHIVE_DIR:-/var/backups/invoice-archive}"
FULL_BACKUP_DIR="${FULL_BACKUP_DIR:-/var/backups/inventarsystem}"
LOG_DIR="$SCRIPT_DIR/logs"

KEEP_DAYS="${INVOICE_KEEP_DAYS:-3650}"
MODE="auto"
BASE_NAME=""

usage() {
    cat <<EOF
Usage: $0 [options]

Options:
  --invoice-archive-dir DIR   Directory for invoice archive files
  --invoice-keep-days N       Remove archived files older than N days
  --mode auto|docker|host     Backup mode (default: auto)
  --base-name NAME            Base filename prefix for archive files
  -h, --help                  Show this help message
EOF
}

parse_args() {
    while [[ $# -gt 0 ]]; do
        case "$1" in
            --invoice-archive-dir) INVOICE_ARCHIVE_DIR="$2"; shift 2 ;;
            --invoice-keep-days) KEEP_DAYS="$2"; shift 2 ;;
            --mode) MODE="$2"; shift 2 ;;
            --base-name) BASE_NAME="$2"; shift 2 ;;
            -h|--help) usage; exit 0 ;;
            *) echo "Error: unknown option '$1'" >&2; usage; exit 2 ;;
        esac
    done
}

ensure_directory() {
    mkdir -p "$INVOICE_ARCHIVE_DIR"
    mkdir -p "$FULL_BACKUP_DIR"
}

cleanup_old_archives() {
    if [[ -n "$KEEP_DAYS" ]]; then
        find "$INVOICE_ARCHIVE_DIR" -maxdepth 1 -type f -mtime +"$KEEP_DAYS" -print -delete 2>/dev/null || true
    fi
    # Cleanup old bundled backups (older than 30 days)
    find "$FULL_BACKUP_DIR" -maxdepth 1 -type f -name "full_backup_*.tar.gz" -mtime +30 -print -delete 2>/dev/null || true
}

docker_backup() {
    if ! command -v docker >/dev/null 2>&1; then return 1; fi
    
    local timestamp="$(date +'%Y-%m-%d_%H-%M-%S')"
    local staging_dir="/tmp/backup_stage_$timestamp"
    
    echo "[$(date +'%T')] Starting unified system backup..."
    mkdir -p "$staging_dir"

    # 1. MongoDB Dump (into staging)
    if docker compose -f "$COMPOSE_FILE" ps -q mongodb >/dev/null 2>&1; then
        echo "[$(date +'%T')] Dumping Database..."
        docker compose -f "$COMPOSE_FILE" exec -T mongodb mongodump --archive --gzip > "$staging_dir/db.archive.gz"
    fi

    # 2. Archive Assets (into staging)
    if [ -d "./Web/uploads" ]; then
        echo "[$(date +'%T')] Archiving assets..."
        tar -czf "$staging_dir/assets.tar.gz" -C . Web/uploads Web/thumbnails Web/previews 2>/dev/null || true
    fi

    # 3. Archive Logs (into staging)
    if [ -d "$LOG_DIR" ]; then
        echo "[$(date +'%T')] Archiving logs..."
        tar -czf "$staging_dir/logs.tar.gz" -C "$(dirname "$LOG_DIR")" "$(basename "$LOG_DIR")"
    fi

    # 4. Bundle everything into one file
    echo "[$(date +'%T')] Bundling archive..."
    tar -czf "$FULL_BACKUP_DIR/full_backup_$timestamp.tar.gz" -C "$staging_dir" .
    
    # 5. Cleanup staging
    rm -rf "$staging_dir"
    
    echo "[$(date +'%T')] Backup complete: $FULL_BACKUP_DIR/full_backup_$timestamp.tar.gz"
    return 0
}

main() {
    parse_args "$@"
    ensure_directory

    case "$MODE" in
        auto|docker)
            if docker_backup; then
                cleanup_old_archives
                return 0
            fi
            echo "Error: Docker backup failed." >&2
            return 1
            ;;
        *)
            echo "Error: unsupported mode '$MODE'" >&2
            usage
            return 2
            ;;
    esac
}

main "$@"