#include "dynamic_array.h"

#include <assert.h>

void kit_da_init(kit_da_void_t *array, i64 element_size, i64 size,
                 kit_allocator_t *alloc) {
  assert(array != NULL);
  assert(element_size > 0);
  assert(size >= 0);

  memset(array, 0, sizeof(kit_da_void_t));

  if (size > 0)
    array->values = kit_alloc_dispatch(alloc, KIT_ALLOCATE,
                                       element_size * size, 0, NULL);

  if (array->values != NULL) {
    array->capacity = size;
    array->size     = size;
  }

  array->alloc = alloc;
}

static i64 eval_capacity(i64 current_cap, i64 required_cap) {
  if (current_cap == 0)
    return required_cap;
  i64 cap = current_cap;
  while (cap < required_cap) cap *= 2;
  return cap;
}

void kit_da_resize(kit_da_void_t *array, i64 element_size, i64 size) {
  assert(array != NULL);
  assert(element_size > 0);
  assert(size >= 0);

  if (size <= array->capacity) {
    array->size = size;
  } else {
    i64 capacity = eval_capacity(array->capacity, size);

    void *bytes = kit_alloc_dispatch(
        array->alloc, KIT_ALLOCATE, element_size * capacity, 0, NULL);

    if (bytes != NULL) {
      if (array->size > 0)
        memcpy(bytes, array->values, element_size * array->size);
      if (array->values != NULL)
        kit_alloc_dispatch(array->alloc, KIT_DEALLOCATE, 0, 0,
                           array->values);
      array->capacity = capacity;
      array->size     = size;
      array->values   = bytes;
    }
  }
}

void kit_da_resize_exact(kit_da_void_t *array, i64 element_size,
                         i64 capacity) {
  assert(array != NULL);
  assert(element_size > 0);
  assert(capacity >= 0);

  void *bytes = capacity <= 0
                    ? NULL
                    : kit_alloc_dispatch(array->alloc, KIT_ALLOCATE,
                                         element_size * capacity, 0,
                                         NULL);

  if (bytes != NULL || capacity == 0) {
    if (array->size > 0 && capacity > 0)
      memcpy(bytes, array->values, element_size * array->size);
    if (array->values != NULL)
      kit_alloc_dispatch(array->alloc, KIT_DEALLOCATE, 0, 0,
                         array->values);
    array->capacity = capacity;
    array->size     = capacity;
    array->values   = bytes;
  }
}