// file      : build/operation -*- C++ -*-
// copyright : Copyright (c) 2014-2015 Code Synthesis Tools CC
// license   : MIT; see accompanying LICENSE file

#ifndef BUILD_OPERATION
#define BUILD_OPERATION

#include <string>
#include <cstdint>
#include <iosfwd>

#include <build/utility> // string_table

namespace build
{
  // While we are using uint8_t for the meta/operation ids, we assume
  // that each is limited to 4 bits (max 128 entries) so that we can
  // store the combined action id in uint8_t as well. This makes our
  // life easier when it comes to defining switch labels for action
  // ids (no need to mess with endian-ness).
  //
  // Note that 0 is not a valid meta/operation/action id.
  //
  using meta_operation_id = std::uint8_t;
  using operation_id = std::uint8_t;
  using action_id = std::uint8_t;

  struct action
  {
    action (meta_operation_id m, operation_id o): id ((m << 4) | o) {}

    meta_operation_id
    meta_operation () const {return id >> 4;}

    operation_id
    operation () const {return id & 0xF;}

    // Implicit conversion operator to action_id for the switch()
    // statement, etc.
    //
    operator action_id () const {return id;}

    action_id id;
  };

  std::ostream&
  operator<< (std::ostream&, action);

  // Id constants for build-in operations.
  //
  const meta_operation_id perform_id   = 1;
  const meta_operation_id configure_id = 2;
  const meta_operation_id disfigure_id = 3;

  const operation_id update_id = 1;
  const operation_id clean_id  = 2;

  const action_id perform_update_id = (perform_id << 4) | update_id;
  const action_id perform_clean_id  = (perform_id << 4) | clean_id;

  // Meta/operation id tables.
  //
  using meta_operation_table = string_table<meta_operation_id>;
  using operation_table = string_table<operation_id>;

  extern meta_operation_table meta_operations;
  extern operation_table operations;
}

#endif // BUILD_OPERATION