#!/usr/bin/env bash
#
# Obnova Docker dat z NAS zálohy
# - najde nejnovější zálohu pro danou službu
# - zastaví službu, rozbalí data, nastartuje
#
# Použití:
#   sudo bash restore-all.sh                       # obnov vše
#   sudo bash restore-all.sh --only portainer      # jen portainer
#   sudo bash restore-all.sh --from 20240801-120000  # konkrétní záloha
#   sudo bash restore-all.sh --dry-run
#
set -euo pipefail

DEPLOY_USER="${DEPLOY_USER:-deploy}"
DOCKER_HOME="/home/$DEPLOY_USER/docker"
NAS_MOUNT="${NAS_MOUNT:-/Volumes/Backups}"
BACKUP_ROOT="$NAS_MOUNT/Prace/server-backups/$(hostname)"

DRY_RUN=false
ONLY=""
FROM=""

while [[ $# -gt 0 ]]; do
    case $1 in
        --only) ONLY="$2"; shift 2 ;;
        --from) FROM="$2"; shift 2 ;;
        --dry-run) DRY_RUN=true; shift ;;
        *) echo "Neznámý parametr: $1" >&2; exit 1 ;;
    esac
done

[[ $EUID -eq 0 ]] || { echo "Spusť jako root: sudo bash $0" >&2; exit 1; }

run() {
    if $DRY_RUN; then
        echo "[DRY-RUN] $*"
    else
        echo "▶ $*"
        "$@"
    fi
}

[[ -d "$BACKUP_ROOT" ]] || { echo "$BACKUP_ROOT neexistuje" >&2; exit 1; }

for SERVICE_DIR in "$DOCKER_HOME"/*/; do
    SERVICE=$(basename "$SERVICE_DIR")
    [[ -n "$ONLY" && "$SERVICE" != "$ONLY" ]] && continue
    [[ -f "$SERVICE_DIR/docker-compose.yml" ]] || continue

    if [[ -n "$FROM" ]]; then
        BACKUP_FILE="$BACKUP_ROOT/$SERVICE/${SERVICE}-$FROM.tar.zst"
    else
        # Nejnovější záloha
        BACKUP_FILE=$(ls -t "$BACKUP_ROOT/$SERVICE"/${SERVICE}-*.tar.zst 2>/dev/null | head -1 || true)
    fi

    [[ -z "$BACKUP_FILE" || ! -f "$BACKUP_FILE" ]] && { echo "⚠ $SERVICE: žádná záloha, přeskakuji"; continue; }

    echo "▶ $SERVICE: obnovuji z $BACKUP_FILE"
    if ! $DRY_RUN; then
        run docker compose -f "$SERVICE_DIR/docker-compose.yml" stop
        run rm -rf "$SERVICE_DIR/data"
        run mkdir -p "$SERVICE_DIR/data"
        run tar --zstd -xf "$BACKUP_FILE" -C "$SERVICE_DIR"
        run chown -R "$DEPLOY_USER:$DEPLOY_USER" "$SERVICE_DIR/data"
        run docker compose -f "$SERVICE_DIR/docker-compose.yml" up -d
        echo "✓ $SERVICE obnoven"
    fi
done

echo
echo "🎯 Obnova dokončena"