#include "memory/kernel_heap.h"

#include "debug/debug.h"
#include "memory/paging_util.h"

namespace {

static KernelHeap* gKernelHeap = nullptr;

KernelHeap& GetKernelHeap() {
  if (!gKernelHeap) {
    panic("Kernel Heap not initialized.");
  }
  return *gKernelHeap;
}
}  // namespace

KernelHeap::KernelHeap(uint64_t lower_bound, uint64_t upper_bound)
    : next_addr_(lower_bound), upper_bound_(upper_bound) {
  gKernelHeap = this;
}

void* KernelHeap::Allocate(uint64_t size) {
  if (next_addr_ + size >= upper_bound_) {
    panic("Kernel Heap Overrun");
  }
  EnsureResident(next_addr_, size);
  uint64_t address = next_addr_;
  next_addr_ += size;
  return reinterpret_cast<void*>(address);
}

void* operator new(uint64_t size) { return GetKernelHeap().Allocate(size); }
void* operator new[](uint64_t size) { return GetKernelHeap().Allocate(size); }

void operator delete(void*, uint64_t) {}