#pragma once

#include <cstdint>
#include <functional>
#include <optional>
#include <string>
#include <vector>

#include "secsgem/gem/carrier_state.hpp"  // shared CarrierTransition template

// E157 §6 Module Process Tracking — per-module state model for a process
// step within a recipe.  The lifecycle is similar to E40 PJ but scoped
// to a single module step rather than a whole job; an E157 instance is
// typically created per (Module, Substrate, RecipeStep) triple by the
// process executive when a wafer arrives at a module.
//
// Wire-byte values per E157-0712 §10.3.
namespace secsgem::gem {

enum class ModuleState : uint8_t {
  NotExecuting = 0,
  GeneralExecuting = 1,    // setup, pre-process, etc.
  StepExecuting    = 2,    // actively running the recipe step
  StepCompleted    = 3,
  NoState          = 255,
};

const char* module_state_name(ModuleState s);
std::optional<ModuleState> parse_module_state(const std::string& s);

enum class ModuleEvent {
  StartGeneral,    // NotExecuting -> GeneralExecuting
  StartStep,       // GeneralExecuting -> StepExecuting
  CompleteStep,    // StepExecuting -> StepCompleted
  Reset,           // any -> NotExecuting (cancellation)
  Abort,           // any -> StepCompleted (early termination)
};

const char* module_event_name(ModuleEvent e);

using ModuleTable = CarrierTransitionTable<ModuleState, ModuleEvent>;
ModuleTable default_module_table();

class ModuleStateMachine {
 public:
  using StateChangeHandler =
      std::function<void(ModuleState from, ModuleState to, ModuleEvent)>;

  ModuleStateMachine();

  ModuleState state() const { return state_; }
  void set_state_change_handler(StateChangeHandler h) { on_change_ = std::move(h); }

  bool on_event(ModuleEvent e);

 private:
  ModuleTable table_;
  ModuleState state_ = ModuleState::NotExecuting;
  StateChangeHandler on_change_;
};

}  // namespace secsgem::gem