#include "e.h"

struct _E_Powersave_Deferred_Action
{
   void          (*func)(void *data);
   const void   *data;
   unsigned char delete_me : 1;
};

/* local subsystem functions */
static Eina_Bool _e_powersave_cb_deferred_timer(void *data);
static void      _e_powersave_mode_eval(void);
static void      _e_powersave_event_update_free(void *data __UNUSED__, void *event);

/* local subsystem globals */
EAPI int E_EVENT_POWERSAVE_UPDATE = 0;
EAPI int E_EVENT_POWERSAVE_CONFIG_UPDATE = 0;
static int walking_deferred_actions = 0;
static Eina_List *deferred_actions = NULL;
static Ecore_Timer *deferred_timer = NULL;
static E_Powersave_Mode powersave_mode = E_POWERSAVE_MODE_LOW;
static double defer_time = 5.0;

/* externally accessible functions */
EINTERN int
e_powersave_init(void)
{
   _e_powersave_mode_eval();
   E_EVENT_POWERSAVE_UPDATE = ecore_event_type_new();
   E_EVENT_POWERSAVE_CONFIG_UPDATE = ecore_event_type_new();
   return 1;
}

EINTERN int
e_powersave_shutdown(void)
{
   return 1;
}

EAPI E_Powersave_Deferred_Action *
e_powersave_deferred_action_add(void (*func)(void *data), const void *data)
{
   E_Powersave_Deferred_Action *pa;

   pa = calloc(1, sizeof(E_Powersave_Deferred_Action));
   if (!pa) return NULL;
   if (deferred_timer) ecore_timer_del(deferred_timer);
   deferred_timer = ecore_timer_add(defer_time,
                                    _e_powersave_cb_deferred_timer,
                                    NULL);
   pa->func = func;
   pa->data = data;
   deferred_actions = eina_list_append(deferred_actions, pa);
   return pa;
}

EAPI void
e_powersave_deferred_action_del(E_Powersave_Deferred_Action *pa)
{
   if (walking_deferred_actions)
     {
        pa->delete_me = 1;
        return;
     }
   else
     {
        deferred_actions = eina_list_remove(deferred_actions, pa);
        free(pa);
        if (!deferred_actions)
          {
             if (deferred_timer)
               {
                  ecore_timer_del(deferred_timer);
                  deferred_timer = NULL;
               }
          }
     }
}

EAPI void
e_powersave_mode_set(E_Powersave_Mode mode)
{
   E_Event_Powersave_Update *ev;

   if (mode < e_config->powersave.min) mode = e_config->powersave.min;
   else if (mode > e_config->powersave.max)
     mode = e_config->powersave.max;
   if (powersave_mode == mode) return;
   printf("CHANGE PW SAVE MODE TO %i / %i\n", (int)mode, E_POWERSAVE_MODE_EXTREME);
   powersave_mode = mode;

   ev = E_NEW(E_Event_Powersave_Update, 1);
   ev->mode = mode;
   ecore_event_add(E_EVENT_POWERSAVE_UPDATE, ev, _e_powersave_event_update_free, NULL);
   _e_powersave_mode_eval();
}

EAPI E_Powersave_Mode
e_powersave_mode_get(void)
{
   return powersave_mode;
}

EAPI E_Powersave_Mode
e_powersave_mode_min_get(void)
{
   return e_config->powersave.min;
}

EAPI E_Powersave_Mode
e_powersave_mode_max_get(void)
{
   return e_config->powersave.max;
}

/* local subsystem functions */

static Eina_Bool
_e_powersave_cb_deferred_timer(void *data __UNUSED__)
{
   E_Powersave_Deferred_Action *pa;

   walking_deferred_actions++;
   EINA_LIST_FREE(deferred_actions, pa)
     {
        if (!pa->delete_me) pa->func((void *)pa->data);
        free(pa);
     }
   walking_deferred_actions--;
   if (!deferred_actions) deferred_timer = NULL;
   return ECORE_CALLBACK_CANCEL;
}

static void
_e_powersave_mode_eval(void)
{
   double t = 0.0;

   switch (powersave_mode)
     {
      case E_POWERSAVE_MODE_NONE:
        t = e_config->powersave.none; /* time to defer "power expensive" activities */
        break;

      case E_POWERSAVE_MODE_LOW:
        t = e_config->powersave.low;
        break;

      case E_POWERSAVE_MODE_MEDIUM:
        t = e_config->powersave.medium;
        break;

      case E_POWERSAVE_MODE_HIGH:
        t = e_config->powersave.high;
        break;

      case E_POWERSAVE_MODE_EXTREME:
        t = e_config->powersave.extreme;
        break;

      default:
        return;
        break;
     }
   if (t != defer_time)
     {
        if (deferred_timer) ecore_timer_del(deferred_timer);
        deferred_timer = ecore_timer_add(defer_time,
                                         _e_powersave_cb_deferred_timer,
                                         NULL);
        defer_time = t;
     }
}

static void
_e_powersave_event_update_free(void *data __UNUSED__, void *event)
{
   free(event);
}