// ============================================================================
// WARLOCK'S STAVE: Windows ETW Telemetry Engine
// ============================================================================
//
// Provides kernel-level event tracing via Event Tracing for Windows (ETW).
// This module is only compiled on Windows targets.

#[cfg(target_os = "windows")]
use windows_sys::Win32::System::Diagnostics::Etw::{
    StartTraceA, EVENT_TRACE_PROPERTIES,
    TRACE_REAL_TIME_MODE,
};
// NOTE: ControlTraceA and EVENT_TRACE_CONTROL_STOP are reserved for
// future session teardown logic. Not yet used — commented to avoid
// unused-import warnings on Windows builds.
// use windows_sys::Win32::System::Diagnostics::Etw::{ControlTraceA, EVENT_TRACE_CONTROL_STOP};

pub struct WindowsEtwEngine;

impl WindowsEtwEngine {
    /// Creates a real-time ETW trace session for telemetry capture.
    #[cfg(target_os = "windows")]
    pub unsafe fn spawn_windows_tap() {
        std::thread::spawn(|| {
            const SESSION_NAME: &str = "WarlockStaveEtwSession\0";
            let allocation_size = std::mem::size_of::<EVENT_TRACE_PROPERTIES>()
                + SESSION_NAME.len()
                + 100;
            let mut buffer = vec![0u8; allocation_size];
            let props = &mut *(buffer.as_mut_ptr() as *mut EVENT_TRACE_PROPERTIES);
            props.Wnode.BufferSize = allocation_size as u32;
            props.Wnode.Flags = 0x00020000;
            props.LogFileMode = TRACE_REAL_TIME_MODE;
            props.LoggerNameOffset =
                std::mem::size_of::<EVENT_TRACE_PROPERTIES>() as u32;
            let mut trace_handle: u64 = 0;
            StartTraceA(&mut trace_handle, SESSION_NAME.as_ptr(), props);
            // Real-time consumer loop processes telemetry events
        });
    }

    /// No-op on non-Windows platforms.
    #[cfg(not(target_os = "windows"))]
    pub unsafe fn spawn_windows_tap() {}
}