#pragma once

#include <BAN/Vector.h>
#include <kernel/Memory/Types.h>

namespace Kernel
{

	class ACPI
	{
	public:
		struct GAS
		{
			uint8_t address_space_id;
			uint8_t register_bit_width;
			uint8_t register_bit_offset;
			uint8_t access_size;
			uint64_t address;
		} __attribute__((packed));

		struct SDTHeader
		{
			uint8_t signature[4];
			uint32_t length;
			uint8_t revision;
			uint8_t checksum;
			uint8_t oemid[6];
			uint64_t oem_table_id;
			uint32_t oem_revision;
			uint32_t creator_id;
			uint32_t creator_revision;
		} __attribute__((packed));

		struct FADT : public SDTHeader
		{
			uint32_t firmware_ctrl;
			uint32_t dsdt;
			uint8_t __reserved;
			uint8_t preferred_pm_profile;
			uint16_t sci_int;
			uint32_t smi_cmd;
			uint8_t acpi_enable;
			uint8_t acpi_disable;
			uint8_t s4bios_req;
			uint8_t pstate_cnt;
			uint32_t pm1a_evt_blk;
			uint32_t pm1b_evt_blk;
			uint32_t pm1a_cnt_blk;
			uint32_t pm1b_cnt_blk;
			uint32_t pm2_cnt_blk;
			uint32_t pm_tmr_blk;
			uint32_t gpe0_blk;
			uint32_t gpe1_blk;
			uint8_t pm1_evt_len;
			uint8_t pm1_cnt_len;
			uint8_t pm2_cnt_len;
			uint8_t pm_tmr_len;
			uint8_t gpe0_blk_len;
			uint8_t gpe1_blk_len;
			uint8_t gpe1_base;
			uint8_t cst_cnt;
			uint16_t p_lvl2_lat;
			uint16_t p_lvl3_lat;
			uint16_t flush_size;
			uint16_t flush_stride;
			uint8_t duty_offset;
			uint8_t duty_width;
			uint8_t day_alrm;
			uint8_t mon_alrm;
			uint8_t century;
			uint16_t iapc_boot_arch;
			uint8_t __reserved2;
			uint32_t flags;
			uint8_t reset_reg[12];
			uint8_t reset_value;
			uint16_t arm_boot_arch;
			uint8_t fadt_minor_version;
			uint64_t x_firmware_version;
			uint64_t x_dsdt;
			uint8_t x_pm1a_evt_blk[12];
			uint8_t x_pm1b_evt_blk[12];
			uint8_t x_pm1a_cnt_blk[12];
			uint8_t x_pm1b_cnt_blk[12];
			uint8_t x_pm2_cnt_blk[12];
			uint8_t x_pm_tmr_blk[12];
			uint8_t x_gpe0_blk[12];
			uint8_t x_gpe1_blk[12];
			uint8_t sleep_control_reg[12];
			uint8_t sleep_status_reg[12];
			uint64_t hypervison_vendor_identity;
		} __attribute__((packed));

		struct HPET : public SDTHeader
		{
			uint8_t hardware_rev_id;
			uint8_t comparator_count : 5;
			uint8_t count_size_cap : 1;
			uint8_t reserved : 1;
			uint8_t legacy_replacement_irq_routing_cable : 1;
			uint16_t pci_vendor_id;
			GAS base_address;
			uint8_t hpet_number;
			uint16_t main_counter_minimum_clock_tick;
			uint8_t page_protection_and_oem_attribute;
		} __attribute__((packed));

	public:
		static BAN::ErrorOr<void> initialize();
		static ACPI& get();

		const SDTHeader* get_header(BAN::StringView signature, uint32_t index);

	private:
		ACPI() = default;
		BAN::ErrorOr<void> initialize_impl();

	private:
		paddr_t m_header_table_paddr = 0;
		vaddr_t m_header_table_vaddr = 0;
		uint32_t m_entry_size = 0;

		struct MappedPage
		{
			Kernel::paddr_t paddr;
			Kernel::vaddr_t vaddr;

			SDTHeader* as_header() { return (SDTHeader*)vaddr; }
		};
		BAN::Vector<MappedPage> m_mapped_headers;		
	};

}

namespace BAN::Formatter
{
	template<typename F>
	void print_argument(F putc, const Kernel::ACPI::SDTHeader& header, const ValueFormat& format)
	{ 
		putc(header.signature[0]);
		putc(header.signature[1]);
		putc(header.signature[2]);
		putc(header.signature[3]);
	}
}