/**
 * Copyright (c) 2025 Dominic Masters
 * 
 * This software is released under the MIT License.
 * https://opensource.org/licenses/MIT
 */

#include "time.h"
#include "util/memory.h"
#include "assert/assert.h"

#if TIME_SDL2
  #include <SDL2/SDL.h>
#endif

dusktime_t TIME;

void timeInit(void) {
  memoryZero(&TIME, sizeof(TIME));

  // Set these to something non-zero.
  TIME.time = TIME_STEP;
  TIME.delta = TIME_STEP;

  TIME.fixedDelta = TIME_STEP;
  TIME.fixedTime = TIME_STEP;
}

void timeUpdate(void) {
  float_t delta;
  #if TIME_SDL2
    delta = (float_t)SDL_GetTicks() / 1000.0f - TIME.time;
  #elif TIME_FIXED
    delta = TIME_PLATFORM_STEP;
  #else
    #error "No time platform defined"
  #endif

  TIME.delta = delta;
  assertTrue(TIME.delta >= 0.0f, "Time delta is negative");
  TIME.time += TIME.delta;

  // Perform a fixed time step.
  if(TIME.time - TIME.fixedTime >= (TIME_STEP * 0.9f)) {
    TIME.fixedUpdate = true;
    TIME.fixedDelta = TIME_STEP;
    TIME.fixedTime += TIME_STEP;
  } else {
    TIME.fixedDelta = 0.0f;
    TIME.fixedUpdate = false;
  }
}