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

PROJECT_DIR="$(cd "$(dirname "$0")" && pwd)"
cd "$PROJECT_DIR"

COMPOSE="docker compose"
SERVICE="garage"
GARAGE_BIN="/garage"
GARAGE_CMD="$COMPOSE exec -T $SERVICE $GARAGE_BIN"

ZONE="${GARAGE_LAYOUT_ZONE:-dc1}"
FORCE_CAPACITY_UPDATE=false

for arg in "$@"; do
  case "$arg" in
    --force-capacity-update)
      FORCE_CAPACITY_UPDATE=true
      ;;
    -h|--help)
      echo "Uso: $0 [--force-capacity-update]"
      echo
      echo "  --force-capacity-update   Riapplica layout se la capacità rilevata differisce da quella attuale del nodo"
      exit 0
      ;;
    *)
      echo "Errore: opzione non riconosciuta: $arg" >&2
      echo "Usa --help per vedere le opzioni disponibili." >&2
      exit 1
      ;;
  esac
done

get_env_value() {
  local key="$1"
  local env_file="$PROJECT_DIR/.env"

  if [[ -n "${!key:-}" ]]; then
    printf '%s' "${!key}"
    return 0
  fi

  if [[ -f "$env_file" ]]; then
    awk -F= -v k="$key" '$1==k {print $2; exit}' "$env_file"
    return 0
  fi

  return 1
}

detect_capacity_gb() {
  local data_path="$1"
  local normalized_path="$data_path"

  if [[ "$data_path" != /* ]]; then
    normalized_path="$PROJECT_DIR/$data_path"
  fi

  if [[ ! -d "$normalized_path" ]]; then
    return 1
  fi

  local size_gb
  size_gb="$(df -BG --output=size "$normalized_path" 2>/dev/null | awk 'NR==2 {gsub(/G/,"",$1); print $1}')"
  if [[ "$size_gb" =~ ^[0-9]+$ ]] && [[ "$size_gb" -gt 0 ]]; then
    printf '%sG' "$size_gb"
    return 0
  fi

  local used_gb
  used_gb="$(du -sBG "$normalized_path" 2>/dev/null | awk '{gsub(/G/,"",$1); print $1}')"
  if [[ "$used_gb" =~ ^[0-9]+$ ]] && [[ "$used_gb" -gt 0 ]]; then
    printf '%sG' "$used_gb"
    return 0
  fi

  return 1
}

if [[ -n "${GARAGE_LAYOUT_CAPACITY:-}" ]]; then
  CAPACITY="$GARAGE_LAYOUT_CAPACITY"
else
  DATA_PATH="$(get_env_value "GARAGE_DATA_PATH")"
  if CAPACITY="$(detect_capacity_gb "$DATA_PATH")"; then
    echo "Capacità auto-rilevata da GARAGE_DATA_PATH ($DATA_PATH): $CAPACITY"
  else
    CAPACITY="100G"
    echo "Avviso: capacità non rilevabile da GARAGE_DATA_PATH (${DATA_PATH:-unset}), uso fallback $CAPACITY" >&2
  fi
fi

if ! command -v docker >/dev/null 2>&1; then
  echo "Errore: docker non trovato nel PATH." >&2
  exit 1
fi

if ! $COMPOSE ps --status running "$SERVICE" >/dev/null 2>&1; then
  echo "Errore: il servizio '$SERVICE' non risulta avviato. Esegui: docker compose up -d" >&2
  exit 1
fi

LAYOUT_OUTPUT="$($GARAGE_CMD layout show)"
LAYOUT_VERSION="$(printf '%s\n' "$LAYOUT_OUTPUT" | sed -n 's/^Current cluster layout version: \([0-9][0-9]*\)$/\1/p')"
LAYOUT_VERSION="${LAYOUT_VERSION:-0}"

STATUS_OUTPUT="$($GARAGE_CMD status)"

NODE_ID="$(printf '%s\n' "$STATUS_OUTPUT" | awk '
  /==== HEALTHY NODES ====/ {in_table=1; next}
  in_table && /^ID[[:space:]]+/ {next}
  in_table && /^[0-9a-f]{8,}/ {print $1; exit}
')"

if [[ -z "$NODE_ID" ]]; then
  echo "Errore: nessun nodo healthy trovato su cui applicare il layout." >&2
  exit 1
fi

CURRENT_CAPACITY_GB="$(printf '%s\n' "$STATUS_OUTPUT" | awk -v id="$NODE_ID" '$1==id {for (i=1;i<=NF;i++) if ($i ~ /^[0-9.]+$/) {print int($i); exit}}')"
TARGET_CAPACITY_GB="$(printf '%s\n' "$CAPACITY" | sed -n 's/^\([0-9][0-9]*\)G$/\1/p')"

NEEDS_LAYOUT_APPLY=false
if printf '%s\n' "$STATUS_OUTPUT" | grep -q 'NO ROLE ASSIGNED' || [[ "$LAYOUT_VERSION" -eq 0 ]]; then
  NEEDS_LAYOUT_APPLY=true
elif [[ "$FORCE_CAPACITY_UPDATE" == true ]] && [[ -n "$CURRENT_CAPACITY_GB" ]] && [[ -n "$TARGET_CAPACITY_GB" ]] && [[ "$CURRENT_CAPACITY_GB" -ne "$TARGET_CAPACITY_GB" ]]; then
  NEEDS_LAYOUT_APPLY=true
fi

if [[ "$NEEDS_LAYOUT_APPLY" == true ]]; then
  NEXT_VERSION=$((LAYOUT_VERSION + 1))

  if [[ "$FORCE_CAPACITY_UPDATE" == true ]] && [[ "$LAYOUT_VERSION" -gt 0 ]]; then
    echo "Aggiornamento capacità forzato richiesto (attuale=${CURRENT_CAPACITY_GB:-unknown}G, target=$CAPACITY)."
  else
    echo "Layout non pronto (version=$LAYOUT_VERSION)."
  fi
  echo "Applico ruolo al nodo $NODE_ID (zone=$ZONE, capacity=$CAPACITY)..."

  $GARAGE_CMD layout assign -z "$ZONE" -c "$CAPACITY" "$NODE_ID" >/dev/null
  $GARAGE_CMD layout apply --version "$NEXT_VERSION" >/dev/null

  echo "Layout applicato (version=$NEXT_VERSION)."
else
  echo "Layout già pronto (version=$LAYOUT_VERSION), nessuna modifica necessaria."
fi

echo
$GARAGE_CMD status