    const std = @import("../std.zig");

    /// A protocol is an interface identified by a GUID.
    pub const protocols = @import("uefi/protocols.zig");

    /// Status codes returned by EFI interfaces
    pub const Status = @import("uefi/status.zig").Status;
    pub const tables = @import("uefi/tables.zig");

    /// The memory type to allocate when using the pool
    /// Defaults to .LoaderData, the default data allocation type
    /// used by UEFI applications to allocate pool memory.
    pub var efi_pool_memory_type: tables.MemoryType = .LoaderData;
    pub const pool_allocator = @import("uefi/pool_allocator.zig").pool_allocator;
    pub const raw_pool_allocator = @import("uefi/pool_allocator.zig").raw_pool_allocator;

    /// The EFI image's handle that is passed to its entry point.
    pub var handle: Handle = undefined;

    /// A pointer to the EFI System Table that is passed to the EFI image's entry point.
    pub var system_table: *tables.SystemTable = undefined;

    /// A handle to an event structure.
    pub const Event = *opaque {};

    pub const MacAddress = extern struct {
        address: [32]u8,
    };

    pub const Ipv4Address = extern struct {
        address: [4]u8,
    };

    pub const Ipv6Address = extern struct {
        address: [16]u8,
    };

    /// GUIDs are align(8) unless otherwise specified.
    pub const Guid = extern struct {
        time_low: u32,
        time_mid: u16,
        time_high_and_version: u16,
        clock_seq_high_and_reserved: u8,
        clock_seq_low: u8,
        node: [6]u8,

        /// Format GUID into hexadecimal lowercase xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx format
        pub fn format(
            self: @This(),
            comptime f: []const u8,
            options: std.fmt.FormatOptions,
            writer: anytype,
        ) !void {
            _ = options;
            if (f.len == 0) {
                const fmt = std.fmt.fmtSliceHexLower;

                const time_low = @byteSwap(self.time_low);
                const time_mid = @byteSwap(self.time_mid);
                const time_high_and_version = @byteSwap(self.time_high_and_version);

                return std.fmt.format(writer, "{:0>8}-{:0>4}-{:0>4}-{:0>2}{:0>2}-{:0>12}", .{
                    fmt(std.mem.asBytes(&time_low)),
                    fmt(std.mem.asBytes(&time_mid)),
                    fmt(std.mem.asBytes(&time_high_and_version)),
                    fmt(std.mem.asBytes(&self.clock_seq_high_and_reserved)),
                    fmt(std.mem.asBytes(&self.clock_seq_low)),
                    fmt(std.mem.asBytes(&self.node)),
                });
            } else {
                @compileError("Unknown format character: '" ++ f ++ "'");
            }
        }

        pub fn eql(a: std.os.uefi.Guid, b: std.os.uefi.Guid) bool {
            return a.time_low == b.time_low and
                a.time_mid == b.time_mid and
                a.time_high_and_version == b.time_high_and_version and
                a.clock_seq_high_and_reserved == b.clock_seq_high_and_reserved and
                a.clock_seq_low == b.clock_seq_low and
                std.mem.eql(u8, &a.node, &b.node);
        }
    };

    /// An EFI Handle represents a collection of related interfaces.
    pub const Handle = *opaque {};

    /// This structure represents time information.
    pub const Time = extern struct {
        /// 1900 - 9999
        year: u16,

        /// 1 - 12
        month: u8,

        /// 1 - 31
        day: u8,

        /// 0 - 23
        hour: u8,

        /// 0 - 59
        minute: u8,

        /// 0 - 59
        second: u8,

        /// 0 - 999999999
        nanosecond: u32,

        /// The time's offset in minutes from UTC.
        /// Allowed values are -1440 to 1440 or unspecified_timezone
        timezone: i16,
        daylight: packed struct {
            _pad1: u6,

            /// If true, the time has been adjusted for daylight savings time.
            in_daylight: bool,

            /// If true, the time is affected by daylight savings time.
            adjust_daylight: bool,
        },

        /// Time is to be interpreted as local time
        pub const unspecified_timezone: i16 = 0x7ff;
    };

    /// Capabilities of the clock device
    pub const TimeCapabilities = extern struct {
        /// Resolution in Hz
        resolution: u32,

        /// Accuracy in an error rate of 1e-6 parts per million.
        accuracy: u32,

        /// If true, a time set operation clears the device's time below the resolution level.
        sets_to_zero: bool,
    };

    /// File Handle as specified in the EFI Shell Spec
    pub const FileHandle = *opaque {};

    test "GUID formatting" {
        var bytes = [_]u8{ 137, 60, 203, 50, 128, 128, 124, 66, 186, 19, 80, 73, 135, 59, 194, 135 };

        var guid = @bitCast(Guid, bytes);

        var str = try std.fmt.allocPrint(std.testing.allocator, "{}", .{guid});
        defer std.testing.allocator.free(str);

        try std.testing.expect(std.mem.eql(u8, str, "32cb3c89-8080-427c-ba13-5049873bc287"));
    }

    test {
        _ = tables;
        _ = protocols;
    }