using System.Runtime.InteropServices;
namespace XFESystem.NativeKernel;

public static unsafe class ThreadBridge
{
    [UnmanagedCallersOnly(EntryPoint = "xfe_runtime_physical_bytes")]
    public static ulong PhysicalBytes() => PhysicalMemory.TotalPages * 4096;
    [UnmanagedCallersOnly(EntryPoint = "xfe_runtime_free_physical_bytes")]
    public static ulong FreePhysicalBytes() => PhysicalMemory.AvailablePages * 4096;
    [UnmanagedCallersOnly(EntryPoint = "xfe_runtime_thread_id")]
    public static ulong CurrentThread() => Threads.Ready ? Threads.Current->Id : 0;
    [UnmanagedCallersOnly(EntryPoint = "xfe_runtime_stack_bounds")]
    public static int StackBounds(void** low, void** high) => Threads.StackBounds(low, high) ? 1 : 0;
    [UnmanagedCallersOnly(EntryPoint = "xfe_runtime_thread_start")]
    public static int Start(delegate* unmanaged<void*, uint> entry, void* argument, ulong stackBytes)
    {
        if (!Threads.Ready || entry == null) return 0;
        ulong tls = Native.ThreadTlsCreate();
        if (tls == 0) return 0; // Full runtime absent: refuse, never fabricate TLS.
        ulong id = Threads.Create(entry, argument, stackBytes, tls, true);
        if (id == 0) Native.ThreadTlsRelease(tls);
        return id == 0 ? 0 : 1;
    }
    [UnmanagedCallersOnly(EntryPoint = "xfe_runtime_thread_sleep")]
    public static void Sleep(uint milliseconds) => Threads.Sleep(milliseconds);
    [UnmanagedCallersOnly(EntryPoint = "xfe_runtime_thread_yield")]
    public static void Yield() => Threads.Yield();
    [UnmanagedCallersOnly(EntryPoint = "xfe_runtime_event_create")]
    public static void* CreateEvent(int manual, int initial) => (void*)KernelEvents.Create(manual != 0, initial != 0);
    [UnmanagedCallersOnly(EntryPoint = "xfe_runtime_event_close")]
    public static int CloseEvent(void* handle) => KernelEvents.Close((ulong)handle) ? 1 : 0;
    [UnmanagedCallersOnly(EntryPoint = "xfe_runtime_event_set")]
    public static int SetEvent(void* handle) => KernelEvents.Set((ulong)handle) ? 1 : 0;
    [UnmanagedCallersOnly(EntryPoint = "xfe_runtime_event_reset")]
    public static int ResetEvent(void* handle) => KernelEvents.Reset((ulong)handle) ? 1 : 0;
    [UnmanagedCallersOnly(EntryPoint = "xfe_runtime_event_wait")]
    public static uint WaitEvent(void* handle, uint milliseconds) { ulong value = (ulong)handle; return KernelEvents.Wait(&value, 1, milliseconds); }
    [UnmanagedCallersOnly(EntryPoint = "xfe_runtime_event_wait_any")]
    public static uint WaitAny(void** handles, uint count, uint milliseconds) => KernelEvents.Wait((ulong*)handles, count, milliseconds);
    [UnmanagedCallersOnly(EntryPoint = "xfe_runtime_thread_attach")]
    public static void Attach(void* runtimeThread) => Threads.Attach(runtimeThread);
    [UnmanagedCallersOnly(EntryPoint = "xfe_runtime_thread_gc_hijack")]
    public static int RequestHijack(void* runtimeThread) => Threads.RequestHijack(runtimeThread);
}