#pragma once

#include <kernel/Memory/MemoryRegion.h>

namespace Kernel
{

	class MemoryBackedRegion final : public MemoryRegion
	{
		BAN_NON_COPYABLE(MemoryBackedRegion);
		BAN_NON_MOVABLE(MemoryBackedRegion);

	public:
		static BAN::ErrorOr<BAN::UniqPtr<MemoryBackedRegion>> create(PageTable&, size_t size, AddressRange, Type, PageTable::flags_t, int status_flags);
		~MemoryBackedRegion();

		BAN::ErrorOr<BAN::UniqPtr<MemoryRegion>> clone(PageTable& new_page_table) override;
		BAN::ErrorOr<BAN::UniqPtr<MemoryRegion>> split(size_t offset) override;

		BAN::ErrorOr<void> msync(vaddr_t, size_t, int) override { return {}; }

		// Copy data from buffer into this region
		// This can fail if no memory is mapped and no free memory was available
		BAN::ErrorOr<void> copy_data_to_region(size_t offset_into_region, const uint8_t* buffer, size_t buffer_size);

	protected:
		BAN::ErrorOr<bool> allocate_page_containing_impl(vaddr_t vaddr, bool wants_write) override;

	private:
		MemoryBackedRegion(PageTable&, size_t size, Type, PageTable::flags_t, int status_flags);

	private:
		struct PhysicalPage
		{
			PhysicalPage(paddr_t paddr)
				: paddr(paddr)
			{ }
			~PhysicalPage();

			BAN::Atomic<uint32_t> ref_count { 1 };
			const paddr_t paddr;
		};
		BAN::Vector<PhysicalPage*> m_physical_pages;
		Mutex m_mutex;
	};

}