#include <string.h>

#include <engine/dltools.h>
#include <engine/input.h>
#include <engine/logging.h>
#include <engine/state.h>

typedef StateType state_update_t(void*);

const char* StateTypeStr[] = {
    "null",
#define State(name) #name,
#include <states/list_of_states.h>
#undef State
    "quit",
};

// Setup API for states
#define State(name)                                                            \
  typedef struct name##_state name##_state;                                    \
  typedef void(state_##name##_init_t)(name##_state*);                          \
  typedef void(state_##name##_free_t)(name##_state*);                          \
  typedef StateType(state_##name##_update_t)(name##_state*);
#include <states/list_of_states.h>
#undef State

#ifdef DAW_BUILD_HOTRELOAD

// When hotreloading is enabled, we want to assign state function pointers
// dynamically.
#define State(name)                                                            \
  state_##name##_init_t* name##_init = NULL;                                   \
  state_##name##_free_t* name##_free = NULL;                                   \
  state_##name##_update_t* name##_update = NULL;                               \
                                                                               \
  void* libstate_##name = NULL;                                                \
  const char* libstate_##name##_str = "lib" #name ".so";
#else

// Otherwise we just declare them.
#define State(name)                                                            \
  extern state_##name##_init_t name##_init;                                    \
  extern state_##name##_free_t name##_free;                                    \
  extern state_##name##_update_t name##_update;
#endif

#include <states/list_of_states.h>
#undef State

#include <states/all_states.h>

void binding_t_free(binding_t* b);

void State_init(StateType type, memory* mem) {
  switch (type) {
#define State(name)                                                            \
  case (STATE_##name): {                                                       \
    name##_init(memory_allocate(mem, sizeof(name##_state)));                   \
    break;                                                                     \
  }
#include <states/list_of_states.h>
#undef State
  case STATE_null:
  case STATE_quit:
    DEBUG("Got %s state.\n", StateTypeStr[type]);
    break;
  default:
    exit(EXIT_FAILURE);
  }
}

void State_free(StateType type, memory* mem) {
  switch (type) {
#define State(name)                                                            \
  case (STATE_##name): {                                                       \
    name##_free(mem->data);                                                    \
    break;                                                                     \
  }
#include <states/list_of_states.h>
#undef State
  case STATE_null:
  case STATE_quit:
    DEBUG("Got %s state.\n", StateTypeStr[type]);
    break;
  default:
    exit(EXIT_FAILURE);
  }
  memory_clear(mem);
}

StateType (*State_updateFunc(StateType type))(void*) {
  switch (type) {
#ifdef DAW_BUILD_HOTRELOAD
#define State(name)                                                            \
  case (STATE_##name): {                                                       \
    return (state_update_t*)name##_update;                                     \
    break;                                                                     \
  }
#else
#define State(name)                                                            \
  case (STATE_##name): {                                                       \
    return (state_update_t*)&name##_update;                                    \
    break;                                                                     \
  }
#endif
#include <states/list_of_states.h>
#undef State
  case STATE_null:
  case STATE_quit:
    return NULL;  // DEBUG("Got %s state.\n", StateTypeStr[type]);
    break;
  default:
    exit(EXIT_FAILURE);
  }
  return NULL;
}

StateType State_update(StateType type, memory* mem) {
  StateType next_state = STATE_null;
  switch (type) {
#define State(name)                                                            \
  case (STATE_##name): {                                                       \
    next_state = name##_update(mem->data);                                     \
    break;                                                                     \
  }
#include <states/list_of_states.h>
#undef State
  case STATE_null:
  case STATE_quit:
    DEBUG("Got %s state.\n", StateTypeStr[type]);
    break;
  default:
    exit(EXIT_FAILURE);
  }
  return next_state;
}

#ifdef DAW_BUILD_HOTRELOAD
bool State_reload(StateType type, i_ctx** ctx, usize ctx_len) {
  void* libptr = NULL;

  switch (type) {
#define State(name)                                                            \
  case (STATE_##name): {                                                       \
    if (libstate_##name == NULL) {                                             \
      libstate_##name = dynamic_library_open(libstate_##name##_str);           \
    } else {                                                                   \
      libstate_##name =                                                        \
          dynamic_library_reload(libstate_##name, libstate_##name##_str);      \
    }                                                                          \
    if (libstate_##name == NULL) {                                             \
      ERROR("Failed loading shared object: %s (%s)", libstate_##name##_str,    \
            dynamic_library_get_error());                                      \
      return false;                                                            \
    }                                                                          \
                                                                               \
    name##_init = (state_##name##_init_t*)dynamic_library_get_symbol(          \
        libstate_##name, STR(name##_init));                                    \
    name##_free = (state_##name##_free_t*)dynamic_library_get_symbol(          \
        libstate_##name, STR(name##_free));                                    \
    name##_update = (state_##name##_update_t*)dynamic_library_get_symbol(      \
        libstate_##name, STR(name##_update));                                  \
    libptr = libstate_##name;                                                  \
    break;                                                                     \
  }
#include <states/list_of_states.h>
#undef State
  case STATE_null:
  case STATE_quit:
    ERROR("Invalid state");
    DEBUG("Got %s state.\n", StateTypeStr[type]);
    return false;
  default:
    exit(EXIT_FAILURE);
  }
  return state_refresh_input_ctx(libptr, ctx, ctx_len);
}
#endif