#!/usr/bin/env bash

set -euo pipefail

MODE="${1:-}"

usage() {
  cat >&2 <<'EOF'
Uso:
  server: bootstrap_docs_lan_share.sh server /percorso/day0 192.168.0.0/24 [share_dir] [modules_csv]
  client: bootstrap_docs_lan_share.sh client host:/export/path /mount/point /workspace/path
EOF
  exit 1
}

require_cmd() {
  if ! command -v "$1" >/dev/null 2>&1; then
    echo "Comando richiesto non trovato: $1" >&2
    exit 1
  fi
}

copy_tree() {
  local src="$1"
  local dst="$2"

  mkdir -p "$dst"

  if command -v rsync >/dev/null 2>&1; then
    rsync -a --delete "$src/" "$dst/"
  else
    rm -rf "$dst"
    mkdir -p "$dst"
    cp -a "$src/." "$dst/"
  fi
}

server_mode() {
  local day0_root="${2:-}"
  local network_cidr="${3:-}"
  local share_dir="${4:-/srv/netgescon/shared-docs}"
  local modules_csv="${5:-docs,scripts/ai}"
  local -a module_paths=()
  local module

  [[ -n "$day0_root" && -n "$network_cidr" ]] || usage
  [[ -d "$day0_root/docs" ]] || { echo "docs/ non trovata in $day0_root" >&2; exit 1; }
  [[ -d "$day0_root/scripts/ai" ]] || { echo "scripts/ai non trovata in $day0_root" >&2; exit 1; }

  mkdir -p "$share_dir/scripts" "$share_dir/exchange" "$share_dir/modules"
  copy_tree "$day0_root/docs" "$share_dir/docs"
  copy_tree "$day0_root/scripts/ai" "$share_dir/scripts/ai"

  IFS=',' read -r -a module_paths <<< "$modules_csv"
  for module in "${module_paths[@]}"; do
    module="${module#./}"
    module="${module%/}"

    [[ -n "$module" ]] || continue
    [[ "$module" == "docs" || "$module" == "scripts/ai" ]] && continue

    if [[ -d "$day0_root/$module" ]]; then
      mkdir -p "$share_dir/modules/$(dirname "$module")"
      copy_tree "$day0_root/$module" "$share_dir/modules/$module"
    fi
  done

  cat <<EOF
SERVER_SHARE_DIR=$share_dir
SERVER_EXPORT_LINE=$share_dir $network_cidr(ro,sync,no_subtree_check)

Comandi lato server:
  sudo mkdir -p $share_dir
  echo '$share_dir $network_cidr(ro,sync,no_subtree_check)' | sudo tee /etc/exports.d/netgescon-docs.exports
  sudo exportfs -rav
  sudo systemctl enable --now nfs-server

Contenuto pronto:
  $share_dir/docs
  $share_dir/scripts/ai
  $share_dir/exchange
  $share_dir/modules

Nota moduli:
  moduli richiesti = $modules_csv
  i moduli presenti vengono copiati sotto $share_dir/modules/
EOF
}

client_mode() {
  local remote_export="${2:-}"
  local mount_point="${3:-}"
  local workspace_dir="${4:-}"

  [[ -n "$remote_export" && -n "$mount_point" && -n "$workspace_dir" ]] || usage
  require_cmd ln

  mkdir -p "$mount_point"
  mkdir -p "$workspace_dir/scripts" "$workspace_dir/modules"
  mkdir -p "$workspace_dir/notes"

  ln -sfn "$mount_point/docs" "$workspace_dir/docs"
  ln -sfn "$mount_point/scripts/ai" "$workspace_dir/scripts/ai"
  ln -sfn "$mount_point/exchange" "$workspace_dir/exchange"
  ln -sfn "$mount_point/modules" "$workspace_dir/modules/shared"

  cat <<EOF
CLIENT_REMOTE_EXPORT=$remote_export
CLIENT_MOUNT_POINT=$mount_point
CLIENT_WORKSPACE_DIR=$workspace_dir

Comando mount manuale:
  sudo mount -t nfs $remote_export $mount_point

Riga suggerita per /etc/fstab:
  $remote_export $mount_point nfs defaults,_netdev 0 0

Workspace pronto:
  $workspace_dir
  $workspace_dir/docs -> $mount_point/docs
  $workspace_dir/scripts/ai -> $mount_point/scripts/ai
  $workspace_dir/exchange -> $mount_point/exchange
  $workspace_dir/modules/shared -> $mount_point/modules
EOF
}

case "$MODE" in
  server)
    server_mode "$@"
    ;;
  client)
    client_mode "$@"
    ;;
  *)
    usage
    ;;
esac