// punktfunk virtual DualSense / DualShock 4 / DualSense Edge — UMDF2 HID minidriver.
//
// A Rust port of the WDK `vhidmini2` UMDF2 sample, reconfigured to present a Sony DualSense
// (VID 054C / PID 0CE6), DualShock 4 (device_type=1) or DualSense Edge (device_type=2) using the
// report descriptors + feature blobs punktfunk already ships in `inject/`. Games see a genuine
// HID PS controller; the host streams input in / reads output (rumble/lightbar/triggers) back.
//
// No WDF object contexts: this is a singleton virtual device, so per-device state lives in statics.
// The host channel is the **sealed pad channel** (design/gamepad-channel-sealing.md, proto v2): the
// whole handshake + all shared-memory access lives in `pf_umdf_util` (the audited unsafe layer), so
// this crate's channel/HID/IOCTL logic is 100% SAFE Rust. The only `unsafe` here is the unavoidable
// WDF setup FFI in DriverEntry/EvtDeviceAdd/the timer, each with a `// SAFETY:` proof.

#![allow(non_snake_case, non_upper_case_globals, clippy::missing_safety_doc)]
// Every remaining `unsafe {}` (all WDF setup FFI) must carry a `// SAFETY:` proof.
#![deny(unsafe_op_in_unsafe_fn)]
#![deny(clippy::undocumented_unsafe_blocks)]

use core::sync::atomic::{AtomicBool, AtomicPtr, AtomicU32, Ordering};

use pf_driver_proto::gamepad::PadShm;
use pf_umdf_util::channel::{ChannelClient, ChannelConfig};
use pf_umdf_util::wdf::{self, Request};
use wdk_sys::{
    NTSTATUS, PCUNICODE_STRING, PDRIVER_OBJECT, PWDFDEVICE_INIT, ULONG, WDF_DRIVER_CONFIG,
    WDF_IO_QUEUE_CONFIG, WDF_NO_HANDLE, WDF_NO_OBJECT_ATTRIBUTES, WDF_OBJECT_ATTRIBUTES,
    WDF_TIMER_CONFIG, WDFDEVICE, WDFDRIVER, WDFQUEUE, WDFQUEUE__, WDFREQUEST, WDFTIMER,
    call_unsafe_wdf_function_binding, windows::OutputDebugStringA,
};

// ---- NTSTATUS values ----
const STATUS_SUCCESS: NTSTATUS = 0;
const STATUS_NOT_IMPLEMENTED: NTSTATUS = 0xC000_0002u32 as NTSTATUS;
const STATUS_INVALID_PARAMETER: NTSTATUS = 0xC000_000Du32 as NTSTATUS;

use pf_umdf_util::nt_success;

// ---- HID minidriver IOCTLs: CTL_CODE(FILE_DEVICE_KEYBOARD=0x0b, id, METHOD_NEITHER=3, ANY) ----
const fn hid_ctl(id: u32) -> u32 {
    (0x0000_000b << 16) | (id << 2) | 3
}
const IOCTL_HID_GET_DEVICE_DESCRIPTOR: u32 = hid_ctl(0);
const IOCTL_HID_GET_REPORT_DESCRIPTOR: u32 = hid_ctl(1);
const IOCTL_HID_READ_REPORT: u32 = hid_ctl(2);
const IOCTL_HID_WRITE_REPORT: u32 = hid_ctl(3);
const IOCTL_HID_GET_DEVICE_ATTRIBUTES: u32 = hid_ctl(9);
const IOCTL_HID_GET_STRING: u32 = hid_ctl(4);
const IOCTL_UMDF_HID_SET_FEATURE: u32 = hid_ctl(20);
const IOCTL_UMDF_HID_GET_FEATURE: u32 = hid_ctl(21);
const IOCTL_UMDF_HID_SET_OUTPUT_REPORT: u32 = hid_ctl(22);
const IOCTL_UMDF_HID_GET_INPUT_REPORT: u32 = hid_ctl(23);

// ---- WDF enum values ----
const WdfIoQueueDispatchParallel: i32 = 2;
const WdfIoQueueDispatchManual: i32 = 3;
const WdfUseDefault: i32 = 2; // WDF_TRI_STATE
const WdfExecutionLevelInheritFromParent: i32 = 1; // WDF_EXECUTION_LEVEL
const WdfSynchronizationScopeInheritFromParent: i32 = 1; // WDF_SYNCHRONIZATION_SCOPE

// ---- DualSense identity ----
const DS_VID: u16 = 0x054C;
const DS_PID: u16 = 0x0CE6;
const DS_VER: u16 = 0x0100;
/// DualShock 4 v2 product id — served (same VID/version) when the host stamps device_type=1.
const DS4_PID: u16 = 0x09CC;
/// DualSense Edge product id — served (same VID/version) when the host stamps device_type=2.
const DS_EDGE_PID: u16 = 0x0DF2;
/// **N4 spike** (gamepad-new-types §6): the Steam Deck controller identity (Valve 28DE:1205),
/// served when the host stamps device_type=3. Exists ONLY to answer the go/no-go question "does
/// Steam Input on Windows promote a software-devnode HID Deck?" — the host never stamps 3
/// outside the `deck-windows-spike` subcommand.
const DECK_VID: u16 = 0x28DE;
const DECK_PID: u16 = 0x1205;

// Sony DualSense USB HID report descriptor (273 bytes), verbatim from inputtino (== inject/dualsense.rs).
// NOTE: inject/dualsense.rs comments this as "232 bytes" — that comment is wrong; it is 273.
#[rustfmt::skip]
static DUALSENSE_RDESC: [u8; 273] = [
    0x05, 0x01, 0x09, 0x05, 0xA1, 0x01, 0x85, 0x01, 0x09, 0x30, 0x09, 0x31, 0x09, 0x32, 0x09, 0x35,
    0x09, 0x33, 0x09, 0x34, 0x15, 0x00, 0x26, 0xFF, 0x00, 0x75, 0x08, 0x95, 0x06, 0x81, 0x02, 0x06,
    0x00, 0xFF, 0x09, 0x20, 0x95, 0x01, 0x81, 0x02, 0x05, 0x01, 0x09, 0x39, 0x15, 0x00, 0x25, 0x07,
    0x35, 0x00, 0x46, 0x3B, 0x01, 0x65, 0x14, 0x75, 0x04, 0x95, 0x01, 0x81, 0x42, 0x65, 0x00, 0x05,
    0x09, 0x19, 0x01, 0x29, 0x0F, 0x15, 0x00, 0x25, 0x01, 0x75, 0x01, 0x95, 0x0F, 0x81, 0x02, 0x06,
    0x00, 0xFF, 0x09, 0x21, 0x95, 0x0D, 0x81, 0x02, 0x06, 0x00, 0xFF, 0x09, 0x22, 0x15, 0x00, 0x26,
    0xFF, 0x00, 0x75, 0x08, 0x95, 0x34, 0x81, 0x02, 0x85, 0x02, 0x09, 0x23, 0x95, 0x2F, 0x91, 0x02,
    0x85, 0x05, 0x09, 0x33, 0x95, 0x28, 0xB1, 0x02, 0x85, 0x08, 0x09, 0x34, 0x95, 0x2F, 0xB1, 0x02,
    0x85, 0x09, 0x09, 0x24, 0x95, 0x13, 0xB1, 0x02, 0x85, 0x0A, 0x09, 0x25, 0x95, 0x1A, 0xB1, 0x02,
    0x85, 0x20, 0x09, 0x26, 0x95, 0x3F, 0xB1, 0x02, 0x85, 0x21, 0x09, 0x27, 0x95, 0x04, 0xB1, 0x02,
    0x85, 0x22, 0x09, 0x40, 0x95, 0x3F, 0xB1, 0x02, 0x85, 0x80, 0x09, 0x28, 0x95, 0x3F, 0xB1, 0x02,
    0x85, 0x81, 0x09, 0x29, 0x95, 0x3F, 0xB1, 0x02, 0x85, 0x82, 0x09, 0x2A, 0x95, 0x09, 0xB1, 0x02,
    0x85, 0x83, 0x09, 0x2B, 0x95, 0x3F, 0xB1, 0x02, 0x85, 0x84, 0x09, 0x2C, 0x95, 0x3F, 0xB1, 0x02,
    0x85, 0x85, 0x09, 0x2D, 0x95, 0x02, 0xB1, 0x02, 0x85, 0xA0, 0x09, 0x2E, 0x95, 0x01, 0xB1, 0x02,
    0x85, 0xE0, 0x09, 0x2F, 0x95, 0x3F, 0xB1, 0x02, 0x85, 0xF0, 0x09, 0x30, 0x95, 0x3F, 0xB1, 0x02,
    0x85, 0xF1, 0x09, 0x31, 0x95, 0x3F, 0xB1, 0x02, 0x85, 0xF2, 0x09, 0x32, 0x95, 0x0F, 0xB1, 0x02,
    0x85, 0xF4, 0x09, 0x35, 0x95, 0x3F, 0xB1, 0x02, 0x85, 0xF5, 0x09, 0x36, 0x95, 0x03, 0xB1, 0x02,
    0xC0,
];

// Feature reports hid-playstation / Steam read during init (each array's first byte is the report id).
#[rustfmt::skip]
static DS_FEATURE_CALIBRATION: [u8; 41] = [ // 0x05 motion calibration: 1 id + 40 data (descriptor declares feature 0x05 as 0x95 0x28 = 40)
    0x05, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10, 0x27, 0xF0, 0xD8, 0x10, 0x27, 0xF0, 0xD8, 0x10,
    0x27, 0xF0, 0xD8, 0xF4, 0x01, 0xF4, 0x01, 0x10, 0x27, 0xF0, 0xD8, 0x10, 0x27, 0xF0, 0xD8, 0x10,
    0x27, 0xF0, 0xD8, 0x0B, 0x00, 0x00, 0x00, 0x00, 0x00,
];
#[rustfmt::skip]
static DS_FEATURE_PAIRING: [u8; 20] = [ // 0x09 pairing info (MAC at 1..7)
    0x09, 0x74, 0xE7, 0xD6, 0x3A, 0x53, 0x35, 0x08, 0x25, 0x00, 0x1E, 0x00, 0xEE, 0x74, 0xD0, 0xBC,
    0x00, 0x00, 0x00, 0x00,
];
#[rustfmt::skip]
static DS_FEATURE_FIRMWARE: [u8; 64] = [ // 0x20 firmware info
    0x20, 0x4A, 0x75, 0x6E, 0x20, 0x31, 0x39, 0x20, 0x32, 0x30, 0x32, 0x33, 0x31, 0x34, 0x3A, 0x34,
    0x37, 0x3A, 0x33, 0x34, 0x03, 0x00, 0x44, 0x00, 0x08, 0x02, 0x00, 0x01, 0x36, 0x00, 0x00, 0x01,
    0xC1, 0xC8, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x54, 0x01, 0x00, 0x00,
    0x14, 0x00, 0x00, 0x00, 0x0B, 0x00, 0x01, 0x00, 0x06, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
];

// ---- DualShock 4 v2 assets (served when the host stamps device_type=1) ----
// Sony DualShock 4 v2 USB HID report descriptor (507 bytes), verbatim from inject/dualshock4.rs.
#[rustfmt::skip]
static DS4_RDESC: [u8; 507] = [
    0x05, 0x01, 0x09, 0x05, 0xA1, 0x01, 0x85, 0x01, 0x09, 0x30, 0x09, 0x31,
    0x09, 0x32, 0x09, 0x35, 0x15, 0x00, 0x26, 0xFF, 0x00, 0x75, 0x08, 0x95,
    0x04, 0x81, 0x02, 0x09, 0x39, 0x15, 0x00, 0x25, 0x07, 0x35, 0x00, 0x46,
    0x3B, 0x01, 0x65, 0x14, 0x75, 0x04, 0x95, 0x01, 0x81, 0x42, 0x65, 0x00,
    0x05, 0x09, 0x19, 0x01, 0x29, 0x0E, 0x15, 0x00, 0x25, 0x01, 0x75, 0x01,
    0x95, 0x0E, 0x81, 0x02, 0x06, 0x00, 0xFF, 0x09, 0x20, 0x75, 0x06, 0x95,
    0x01, 0x15, 0x00, 0x25, 0x7F, 0x81, 0x02, 0x05, 0x01, 0x09, 0x33, 0x09,
    0x34, 0x15, 0x00, 0x26, 0xFF, 0x00, 0x75, 0x08, 0x95, 0x02, 0x81, 0x02,
    0x06, 0x00, 0xFF, 0x09, 0x21, 0x95, 0x36, 0x81, 0x02, 0x85, 0x05, 0x09,
    0x22, 0x95, 0x1F, 0x91, 0x02, 0x85, 0x04, 0x09, 0x23, 0x95, 0x24, 0xB1,
    0x02, 0x85, 0x02, 0x09, 0x24, 0x95, 0x24, 0xB1, 0x02, 0x85, 0x08, 0x09,
    0x25, 0x95, 0x03, 0xB1, 0x02, 0x85, 0x10, 0x09, 0x26, 0x95, 0x04, 0xB1,
    0x02, 0x85, 0x11, 0x09, 0x27, 0x95, 0x02, 0xB1, 0x02, 0x85, 0x12, 0x06,
    0x02, 0xFF, 0x09, 0x21, 0x95, 0x0F, 0xB1, 0x02, 0x85, 0x13, 0x09, 0x22,
    0x95, 0x16, 0xB1, 0x02, 0x85, 0x14, 0x06, 0x05, 0xFF, 0x09, 0x20, 0x95,
    0x10, 0xB1, 0x02, 0x85, 0x15, 0x09, 0x21, 0x95, 0x2C, 0xB1, 0x02, 0x06,
    0x80, 0xFF, 0x85, 0x80, 0x09, 0x20, 0x95, 0x06, 0xB1, 0x02, 0x85, 0x81,
    0x09, 0x21, 0x95, 0x06, 0xB1, 0x02, 0x85, 0x82, 0x09, 0x22, 0x95, 0x05,
    0xB1, 0x02, 0x85, 0x83, 0x09, 0x23, 0x95, 0x01, 0xB1, 0x02, 0x85, 0x84,
    0x09, 0x24, 0x95, 0x04, 0xB1, 0x02, 0x85, 0x85, 0x09, 0x25, 0x95, 0x06,
    0xB1, 0x02, 0x85, 0x86, 0x09, 0x26, 0x95, 0x06, 0xB1, 0x02, 0x85, 0x87,
    0x09, 0x27, 0x95, 0x23, 0xB1, 0x02, 0x85, 0x88, 0x09, 0x28, 0x95, 0x3F,
    0xB1, 0x02, 0x85, 0x89, 0x09, 0x29, 0x95, 0x02, 0xB1, 0x02, 0x85, 0x90,
    0x09, 0x30, 0x95, 0x05, 0xB1, 0x02, 0x85, 0x91, 0x09, 0x31, 0x95, 0x03,
    0xB1, 0x02, 0x85, 0x92, 0x09, 0x32, 0x95, 0x03, 0xB1, 0x02, 0x85, 0x93,
    0x09, 0x33, 0x95, 0x0C, 0xB1, 0x02, 0x85, 0x94, 0x09, 0x34, 0x95, 0x3F,
    0xB1, 0x02, 0x85, 0xA0, 0x09, 0x40, 0x95, 0x06, 0xB1, 0x02, 0x85, 0xA1,
    0x09, 0x41, 0x95, 0x01, 0xB1, 0x02, 0x85, 0xA2, 0x09, 0x42, 0x95, 0x01,
    0xB1, 0x02, 0x85, 0xA3, 0x09, 0x43, 0x95, 0x30, 0xB1, 0x02, 0x85, 0xA4,
    0x09, 0x44, 0x95, 0x0D, 0xB1, 0x02, 0x85, 0xF0, 0x09, 0x47, 0x95, 0x3F,
    0xB1, 0x02, 0x85, 0xF1, 0x09, 0x48, 0x95, 0x3F, 0xB1, 0x02, 0x85, 0xF2,
    0x09, 0x49, 0x95, 0x0F, 0xB1, 0x02, 0x85, 0xA7, 0x09, 0x4A, 0x95, 0x01,
    0xB1, 0x02, 0x85, 0xA8, 0x09, 0x4B, 0x95, 0x01, 0xB1, 0x02, 0x85, 0xA9,
    0x09, 0x4C, 0x95, 0x08, 0xB1, 0x02, 0x85, 0xAA, 0x09, 0x4E, 0x95, 0x01,
    0xB1, 0x02, 0x85, 0xAB, 0x09, 0x4F, 0x95, 0x39, 0xB1, 0x02, 0x85, 0xAC,
    0x09, 0x50, 0x95, 0x39, 0xB1, 0x02, 0x85, 0xAD, 0x09, 0x51, 0x95, 0x0B,
    0xB1, 0x02, 0x85, 0xAE, 0x09, 0x52, 0x95, 0x01, 0xB1, 0x02, 0x85, 0xAF,
    0x09, 0x53, 0x95, 0x02, 0xB1, 0x02, 0x85, 0xB0, 0x09, 0x54, 0x95, 0x3F,
    0xB1, 0x02, 0x85, 0xE0, 0x09, 0x57, 0x95, 0x02, 0xB1, 0x02, 0x85, 0xB3,
    0x09, 0x55, 0x95, 0x3F, 0xB1, 0x02, 0x85, 0xB4, 0x09, 0x55, 0x95, 0x3F,
    0xB1, 0x02, 0x85, 0xB5, 0x09, 0x56, 0x95, 0x3F, 0xB1, 0x02, 0x85, 0xD0,
    0x09, 0x58, 0x95, 0x3F, 0xB1, 0x02, 0x85, 0xD4, 0x09, 0x59, 0x95, 0x3F,
    0xB1, 0x02, 0xC0,
];
// DS4 feature reports games read during init (each array's first byte is the report id).
#[rustfmt::skip]
static DS4_FEATURE_PAIRING: [u8; 16] = [ // 0x12 pairing info (MAC at bytes 1..7)
    0x12, 0x01, 0x00, 0xEF, 0xBE, 0xAD, 0xDE, 0x08, 0x25, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
];
#[rustfmt::skip]
static DS4_FEATURE_CALIBRATION: [u8; 37] = [ // 0x02 IMU calibration
    0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10, 0x00, 0xF0, 0xFF, 0x10, 0x00, 0xF0, 0xFF, 0x10,
    0x00, 0xF0, 0xFF, 0x20, 0x00, 0x20, 0x00, 0x00, 0x20, 0x00, 0xE0, 0x00, 0x20, 0x00, 0xE0, 0x00,
    0x20, 0x00, 0xE0, 0x00, 0x00,
];
#[rustfmt::skip]
static DS4_FEATURE_FIRMWARE: [u8; 49] = [ // 0xa3 firmware/build info
    0xA3, 0x41, 0x75, 0x67, 0x20, 0x20, 0x33, 0x20, 0x32, 0x30, 0x31, 0x33, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x30, 0x37, 0x3A, 0x30, 0x31, 0x3A, 0x31, 0x32, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0xA0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00,
];

// ---- DualSense Edge assets (served when the host stamps device_type=2) ----
// Sony DualSense Edge USB HID report descriptor (389 bytes), verbatim from
// inject/proto/dualsense_proto.rs (a real-device capture; see the provenance note there). Input
// report 0x01 is bit-identical to the plain DualSense — the Edge's Fn/back buttons ride reserved
// bits of buttons[2]; output report 0x02 grows to 63 bytes and 19 profile feature reports are added.
#[rustfmt::skip]
static DS_EDGE_RDESC: [u8; 389] = [
    0x05, 0x01, 0x09, 0x05, 0xA1, 0x01, 0x85, 0x01, 0x09, 0x30, 0x09, 0x31, 0x09, 0x32, 0x09, 0x35,
    0x09, 0x33, 0x09, 0x34, 0x15, 0x00, 0x26, 0xFF, 0x00, 0x75, 0x08, 0x95, 0x06, 0x81, 0x02, 0x06,
    0x00, 0xFF, 0x09, 0x20, 0x95, 0x01, 0x81, 0x02, 0x05, 0x01, 0x09, 0x39, 0x15, 0x00, 0x25, 0x07,
    0x35, 0x00, 0x46, 0x3B, 0x01, 0x65, 0x14, 0x75, 0x04, 0x95, 0x01, 0x81, 0x42, 0x65, 0x00, 0x05,
    0x09, 0x19, 0x01, 0x29, 0x0F, 0x15, 0x00, 0x25, 0x01, 0x75, 0x01, 0x95, 0x0F, 0x81, 0x02, 0x06,
    0x00, 0xFF, 0x09, 0x21, 0x95, 0x0D, 0x81, 0x02, 0x06, 0x00, 0xFF, 0x09, 0x22, 0x15, 0x00, 0x26,
    0xFF, 0x00, 0x75, 0x08, 0x95, 0x34, 0x81, 0x02, 0x85, 0x02, 0x09, 0x23, 0x95, 0x3F, 0x91, 0x02,
    0x85, 0x05, 0x09, 0x33, 0x95, 0x28, 0xB1, 0x02, 0x85, 0x08, 0x09, 0x34, 0x95, 0x2F, 0xB1, 0x02,
    0x85, 0x09, 0x09, 0x24, 0x95, 0x13, 0xB1, 0x02, 0x85, 0x0A, 0x09, 0x25, 0x95, 0x1A, 0xB1, 0x02,
    0x85, 0x20, 0x09, 0x26, 0x95, 0x3F, 0xB1, 0x02, 0x85, 0x21, 0x09, 0x27, 0x95, 0x04, 0xB1, 0x02,
    0x85, 0x22, 0x09, 0x40, 0x95, 0x3F, 0xB1, 0x02, 0x85, 0x80, 0x09, 0x28, 0x95, 0x3F, 0xB1, 0x02,
    0x85, 0x81, 0x09, 0x29, 0x95, 0x3F, 0xB1, 0x02, 0x85, 0x82, 0x09, 0x2A, 0x95, 0x09, 0xB1, 0x02,
    0x85, 0x83, 0x09, 0x2B, 0x95, 0x3F, 0xB1, 0x02, 0x85, 0x84, 0x09, 0x2C, 0x95, 0x3F, 0xB1, 0x02,
    0x85, 0x85, 0x09, 0x2D, 0x95, 0x02, 0xB1, 0x02, 0x85, 0xA0, 0x09, 0x2E, 0x95, 0x01, 0xB1, 0x02,
    0x85, 0xE0, 0x09, 0x2F, 0x95, 0x3F, 0xB1, 0x02, 0x85, 0xF0, 0x09, 0x30, 0x95, 0x3F, 0xB1, 0x02,
    0x85, 0xF1, 0x09, 0x31, 0x95, 0x3F, 0xB1, 0x02, 0x85, 0xF2, 0x09, 0x32, 0x95, 0x34, 0xB1, 0x02,
    0x85, 0xF4, 0x09, 0x35, 0x95, 0x3F, 0xB1, 0x02, 0x85, 0xF5, 0x09, 0x36, 0x95, 0x03, 0xB1, 0x02,
    0x85, 0x60, 0x09, 0x41, 0x95, 0x3F, 0xB1, 0x02, 0x85, 0x61, 0x09, 0x42, 0xB1, 0x02, 0x85, 0x62,
    0x09, 0x43, 0xB1, 0x02, 0x85, 0x63, 0x09, 0x44, 0xB1, 0x02, 0x85, 0x64, 0x09, 0x45, 0xB1, 0x02,
    0x85, 0x65, 0x09, 0x46, 0xB1, 0x02, 0x85, 0x68, 0x09, 0x47, 0xB1, 0x02, 0x85, 0x70, 0x09, 0x48,
    0xB1, 0x02, 0x85, 0x71, 0x09, 0x49, 0xB1, 0x02, 0x85, 0x72, 0x09, 0x4A, 0xB1, 0x02, 0x85, 0x73,
    0x09, 0x4B, 0xB1, 0x02, 0x85, 0x74, 0x09, 0x4C, 0xB1, 0x02, 0x85, 0x75, 0x09, 0x4D, 0xB1, 0x02,
    0x85, 0x76, 0x09, 0x4E, 0xB1, 0x02, 0x85, 0x77, 0x09, 0x4F, 0xB1, 0x02, 0x85, 0x78, 0x09, 0x50,
    0xB1, 0x02, 0x85, 0x79, 0x09, 0x51, 0xB1, 0x02, 0x85, 0x7A, 0x09, 0x52, 0xB1, 0x02, 0x85, 0x7B,
    0x09, 0x53, 0xB1, 0x02, 0xC0,
];

// ---- N4-spike Steam Deck assets (served when the host stamps device_type=3) ----
// The Deck's captured CONTROLLER-interface report descriptor (38 bytes, interface 2 of a real
// 28DE:1205 — verbatim from inject/proto/steam_proto.rs RDESC_DECK_CTRL): one vendor-defined
// (page 0xFFFF) collection with a 64-byte input + 64-byte feature report.
#[rustfmt::skip]
static DECK_RDESC: [u8; 38] = [
    0x06, 0xff, 0xff, 0x09, 0x01, 0xa1, 0x01, 0x09, 0x02, 0x09, 0x03, 0x15, 0x00, 0x26, 0xff, 0x00,
    0x75, 0x08, 0x95, 0x40, 0x81, 0x02, 0x09, 0x06, 0x09, 0x07, 0x15, 0x00, 0x26, 0xff, 0x00, 0x75,
    0x08, 0x95, 0x40, 0xb1, 0x02, 0xc0,
];

// HID descriptor (9 bytes, packed): len, type=0x21, bcdHID=0x0100, country=0, numDesc=1, then
// {reportType=0x22, wReportLength}. DualSense = 273 (0x0111); DualShock 4 = 507 (0x01FB);
// DualSense Edge = 389 (0x0185).
static HID_DESC: [u8; 9] = [0x09, 0x21, 0x00, 0x01, 0x00, 0x01, 0x22, 0x11, 0x01];
static DS4_HID_DESC: [u8; 9] = [0x09, 0x21, 0x00, 0x01, 0x00, 0x01, 0x22, 0xFB, 0x01];
static EDGE_HID_DESC: [u8; 9] = [0x09, 0x21, 0x00, 0x01, 0x00, 0x01, 0x22, 0x85, 0x01];
static DECK_HID_DESC: [u8; 9] = [0x09, 0x21, 0x00, 0x01, 0x00, 0x01, 0x22, 0x26, 0x00]; // 38 bytes

// HID_DEVICE_ATTRIBUTES (32 bytes): Size(u32)=32, VendorID, ProductID, VersionNumber, Reserved[11].
// `devtype` selects the identity: PS family (same Sony VID/version) or the N4-spike Deck.
fn hid_attrs(devtype: u8) -> [u8; 32] {
    let (vid, pid) = match devtype {
        1 => (DS_VID, DS4_PID),
        2 => (DS_VID, DS_EDGE_PID),
        3 => (DECK_VID, DECK_PID),
        _ => (DS_VID, DS_PID),
    };
    let mut a = [0u8; 32];
    a[0..4].copy_from_slice(&32u32.to_le_bytes());
    a[4..6].copy_from_slice(&vid.to_le_bytes());
    a[6..8].copy_from_slice(&pid.to_le_bytes());
    a[8..10].copy_from_slice(&DS_VER.to_le_bytes());
    a
}

// Neutral DualSense input report 0x01 (64 bytes): sticks centered (0x80), triggers 0, dpad neutral (8).
const NEUTRAL_REPORT: [u8; 64] = {
    let mut r = [0u8; 64];
    r[0] = 0x01; // report id
    r[1] = 0x80; // LX
    r[2] = 0x80; // LY
    r[3] = 0x80; // RX
    r[4] = 0x80; // RY
    // r[5]=L2, r[6]=R2 = 0; r[7] = seq counter = 0
    r[8] = 0x08; // buttons[0]: low nibble = dpad hat (8 = neutral), high nibble = face buttons (0)
    r
};
// Neutral DualShock 4 input report 0x01: sticks centered (0x80); the dpad hat is in byte 5 (low
// nibble), so a neutral hat (8) lands there instead of byte 8.
const DS4_NEUTRAL_REPORT: [u8; 64] = {
    let mut r = [0u8; 64];
    r[0] = 0x01; // report id
    r[1] = 0x80; // LX
    r[2] = 0x80; // LY
    r[3] = 0x80; // RX
    r[4] = 0x80; // RY
    r[5] = 0x08; // buttons[0]: low nibble = dpad hat (8 = neutral), high nibble = face buttons (0)
    r
};
// Neutral Steam Deck input frame (unnumbered): header [0x01, 0x00, ID_CONTROLLER_DECK_STATE=0x09,
// payload-len 0x3C], everything released.
const DECK_NEUTRAL_REPORT: [u8; 64] = {
    let mut r = [0u8; 64];
    r[0] = 0x01;
    r[2] = 0x09;
    r[3] = 0x3C;
    r
};
fn neutral_report(devtype: u8) -> [u8; 64] {
    match devtype {
        1 => DS4_NEUTRAL_REPORT,
        3 => DECK_NEUTRAL_REPORT,
        _ => NEUTRAL_REPORT, // DualSense and Edge share the report 0x01 shape
    }
}

static MANUAL_QUEUE: AtomicPtr<WDFQUEUE__> = AtomicPtr::new(core::ptr::null_mut());
/// The latest input report the host pushed (report `0x01`) via shared memory; the timer delivers it
/// to pended game READ_REPORTs. Defaults to neutral until the host connects.
static INPUT_REPORT: std::sync::Mutex<[u8; 64]> = std::sync::Mutex::new(NEUTRAL_REPORT);

// ---- the sealed pad channel: layouts + offsets from pf_driver_proto (drift = compile error) ----
// UMDF runs in WUDFHost.exe (user-mode) and hidclass blocks a control channel on the device stack
// (custom interface CreateFile → err 31; custom IOCTL on the HID handle → err 1) and UMDF has no
// control device. So the DATA section (`PadShm`, 256 B — input report @8, output seq @72, output
// report @76, device_type @140, health marks @144/@148, pad_index @152) is UNNAMED and reached only
// through a handle the SYSTEM host duplicated into this WUDFHost, bootstrapped over the named mailbox
// `Global\pfds-boot-<index>`. The handshake + all shared-memory access live in `pf_umdf_util`.
const SHM_MAGIC: u32 = pf_driver_proto::gamepad::PAD_MAGIC; // "PFDS"
const SHM_SIZE: usize = core::mem::size_of::<PadShm>();
const GAMEPAD_PROTO_VERSION: u32 = pf_driver_proto::gamepad::GAMEPAD_PROTO_VERSION;

// PadShm field offsets (the driver reads input + device_type, writes output + health marks).
const OFF_INPUT: usize = core::mem::offset_of!(PadShm, input);
const OFF_OUT_SEQ: usize = core::mem::offset_of!(PadShm, out_seq);
const OFF_OUTPUT: usize = core::mem::offset_of!(PadShm, output);
const OFF_DEVICE_TYPE: usize = core::mem::offset_of!(PadShm, device_type);
const OFF_DRIVER_PROTO: usize = core::mem::offset_of!(PadShm, driver_proto);
const OFF_DRIVER_HEARTBEAT: usize = core::mem::offset_of!(PadShm, driver_heartbeat);
const OFF_PAD_INDEX: usize = core::mem::offset_of!(PadShm, pad_index);
// v2.1 output-report ring (see PadShm docs in pf_driver_proto).
const OFF_OUT_RING_VER: usize = core::mem::offset_of!(PadShm, out_ring_ver);
const OFF_RING_HEAD: usize = core::mem::offset_of!(PadShm, ring_head);
const OFF_OUT_RING: usize = core::mem::offset_of!(PadShm, out_ring);
const OUT_SLOT_SIZE: usize = core::mem::size_of::<pf_driver_proto::gamepad::OutSlot>();
const OUT_RING_LEN: u32 = pf_driver_proto::gamepad::OUT_RING_LEN;

/// Publish one game output report to the host: the legacy latest-report slot + `out_seq` bump
/// (every host generation reads this), and — when the host stamped `out_ring_ver` (it created the
/// ring region) and our view maps it — the lossless report ring: slot bytes first, `ring_head`
/// bump last, the same publish-then-bump store order the host's Acquire load pairs with on the
/// legacy `out_seq`. The ring is what stops a rumble-STOP report from being coalesced away by a
/// following LED/trigger report inside one host poll window (the confirmed stuck-rumble path).
fn publish_output(view: &pf_umdf_util::section::MappedView, bytes: &[u8]) {
    view.write_bytes(OFF_OUTPUT, bytes);
    let seq = view.read_u32(OFF_OUT_SEQ).wrapping_add(1);
    view.write_u32(OFF_OUT_SEQ, seq);
    if view.mapped_len() >= SHM_SIZE && view.read_u32(OFF_OUT_RING_VER) != 0 {
        let head = view.read_u32(OFF_RING_HEAD);
        let slot = OFF_OUT_RING + (head % OUT_RING_LEN) as usize * OUT_SLOT_SIZE;
        let n = bytes.len().min(64);
        view.write_u32(slot, n as u32);
        view.write_bytes(slot + 4, &bytes[..n]);
        view.write_u32(OFF_RING_HEAD, head.wrapping_add(1));
    }
}

/// The sealed-channel client (per-pad: `ProcessSharingDisabled` gives each pad its own WUDFHost, so
/// this static is per-pad). The handshake/adoption/validation state machine lives in `pf_umdf_util`.
static CHANNEL: ChannelClient = ChannelClient::new();
/// The last observed `device_type` (0 = DualSense, 1 = DualShock 4, 2 = DualSense Edge) — the
/// neutral-report shape when
/// the channel detaches, and the fallback identity while unattached.
static LAST_DEVTYPE: AtomicU32 = AtomicU32::new(0);
/// device_type()'s bounded first-read wait fires at most once (see its docs).
static DEVTYPE_WAITED: AtomicBool = AtomicBool::new(false);

/// This pad's channel config (magic/size/pad_index offset + our logger).
fn channel_cfg() -> ChannelConfig {
    ChannelConfig {
        tag: "pf-ds",
        boot_name_prefix: "Global\\pfds-boot-",
        data_magic: SHM_MAGIC,
        data_size: SHM_SIZE,
        // The v2.1 layout grew by tail extension (the output-report ring); against an old host's
        // 256-byte section the full-size map still succeeds (sections are page-granular), but if
        // it is ever refused, mapping the legacy size keeps the pad alive with the ring disabled.
        min_data_size: pf_driver_proto::gamepad::PAD_SHM_LEGACY_SIZE,
        pad_index_off: OFF_PAD_INDEX,
        log,
    }
}

/// The wire pad index the host stamped into the sealed section (0 while the channel hasn't
/// attached yet). Keys every per-pad identity surface: the Deck unit id + serial, the PS
/// identities' pairing MAC (feature 0x09/0x12) and USB serial string — SDL/Steam dedup
/// controllers by serial, so two virtual pads must never share one (identical serials make a
/// second pad read as the FIRST one re-appearing over another transport, and it is merged).
fn pad_index() -> u8 {
    (CHANNEL
        .data()
        .map(|v| v.read_u32(OFF_PAD_INDEX))
        .unwrap_or(0)
        & 0xFF) as u8
}

/// Whether the world-writable bring-up file log is enabled (resolved once). OPT-IN — debug builds,
/// or the `PFDS_DEBUG_LOG` (system-wide) env var — the same treatment pf-vdisplay got in audit
/// §4.4: a RELEASE driver never writes the Public file (info-leak/DoS surface), and the per-report
/// OUTPUT hex dumps stop being a sustained disk-write path during gameplay. DebugView can't see the
/// UMDF host across session 0, so the file stays the bring-up diagnostic when enabled.
fn file_log_enabled() -> bool {
    use std::sync::OnceLock;
    static ON: OnceLock<bool> = OnceLock::new();
    *ON.get_or_init(|| cfg!(debug_assertions) || std::env::var_os("PFDS_DEBUG_LOG").is_some())
}

/// Process-lifetime append handle to the bring-up log, opened ONCE and shared via a `Mutex`
/// (pf-vdisplay's pattern) — no per-line open/close.
fn file_appender() -> Option<&'static std::sync::Mutex<std::fs::File>> {
    use std::sync::OnceLock;
    static APPENDER: OnceLock<Option<std::sync::Mutex<std::fs::File>>> = OnceLock::new();
    APPENDER
        .get_or_init(|| {
            if !file_log_enabled() {
                return None;
            }
            // WUDFHost's own (LocalService) temp dir — NOT world-writable/readable `C:\Users\Public`,
            // where the OUTPUT/feature-report hex dumps could leak per-pad identity/serial material to
            // any local reader (security-review 2026-07-17). Opt-in/debug only.
            std::fs::OpenOptions::new()
                .create(true)
                .append(true)
                .open(std::env::temp_dir().join("pfds-driver.log"))
                .ok()
                .map(std::sync::Mutex::new)
        })
        .as_ref()
}

fn log(s: &str) {
    if let Ok(c) = std::ffi::CString::new(s) {
        // SAFETY: c is a valid null-terminated string for the duration of the call.
        unsafe { OutputDebugStringA(c.as_ptr().cast()) };
    }
    use std::io::Write;
    if let Some(m) = file_appender()
        && let Ok(mut f) = m.lock()
    {
        let _ = writeln!(f, "{s}");
    }
}
macro_rules! dbglog { ($($a:tt)*) => { log(&format!($($a)*)) } }

#[unsafe(export_name = "DriverEntry")]
pub unsafe extern "system" fn driver_entry(
    driver: PDRIVER_OBJECT,
    registry_path: PCUNICODE_STRING,
) -> NTSTATUS {
    log("[pf-ds] DriverEntry");
    // SAFETY: zeroed WDF_DRIVER_CONFIG is a valid all-null config; we then set Size + the callback.
    let mut config: WDF_DRIVER_CONFIG = unsafe { core::mem::zeroed() };
    config.Size = core::mem::size_of::<WDF_DRIVER_CONFIG>() as ULONG;
    config.EvtDriverDeviceAdd = Some(evt_device_add);

    // SAFETY: all pointers valid; driver/registry_path provided by the loader.
    unsafe {
        call_unsafe_wdf_function_binding!(
            WdfDriverCreate,
            driver,
            registry_path,
            WDF_NO_OBJECT_ATTRIBUTES,
            &mut config,
            WDF_NO_HANDLE.cast::<WDFDRIVER>()
        )
    }
}

extern "C" fn evt_device_add(_driver: WDFDRIVER, mut device_init: PWDFDEVICE_INIT) -> NTSTATUS {
    log("[pf-ds] EvtDeviceAdd");

    // Mark as a filter (HID minidriver sits below mshidumdf.sys).
    // SAFETY: device_init is provided by the framework and non-null.
    unsafe { call_unsafe_wdf_function_binding!(WdfFdoInitSetFilter, device_init) };

    let mut device: WDFDEVICE = core::ptr::null_mut();
    // SAFETY: device_init valid; attributes allowed null; device receives the handle.
    let st = unsafe {
        call_unsafe_wdf_function_binding!(
            WdfDeviceCreate,
            &mut device_init,
            WDF_NO_OBJECT_ATTRIBUTES,
            &mut device
        )
    };
    if !nt_success(st) {
        dbglog!("[pf-ds] WdfDeviceCreate failed 0x{:08x}", st as u32);
        return st;
    }

    // SAFETY: `device` is the live device just created — the exact contract this fn requires.
    let shm_idx = unsafe { wdf::query_location_index(device) };
    CHANNEL.set_index(shm_idx);
    dbglog!("[pf-ds] shm index = {shm_idx}");

    // Default parallel queue handling all IOCTLs.
    // SAFETY: zeroed config then fields set; Size matches the struct.
    let mut qcfg: WDF_IO_QUEUE_CONFIG = unsafe { core::mem::zeroed() };
    qcfg.Size = core::mem::size_of::<WDF_IO_QUEUE_CONFIG>() as ULONG;
    qcfg.DispatchType = WdfIoQueueDispatchParallel;
    qcfg.PowerManaged = WdfUseDefault;
    qcfg.DefaultQueue = 1;
    qcfg.EvtIoDeviceControl = Some(evt_io_device_control);
    // WDF_IO_QUEUE_CONFIG_INIT sets this to (ULONG)-1 (unlimited); mem::zeroed left it 0,
    // which on a parallel queue means present ZERO requests → EvtIoDeviceControl never fires.
    qcfg.Settings.Parallel.NumberOfPresentedRequests = u32::MAX;
    let mut default_queue: WDFQUEUE = core::ptr::null_mut();
    // SAFETY: device + config valid; attributes null; queue receives the handle.
    let st = unsafe {
        call_unsafe_wdf_function_binding!(
            WdfIoQueueCreate,
            device,
            &mut qcfg,
            WDF_NO_OBJECT_ATTRIBUTES,
            &mut default_queue
        )
    };
    if !nt_success(st) {
        dbglog!(
            "[pf-ds] default WdfIoQueueCreate failed 0x{:08x}",
            st as u32
        );
        return st;
    }

    // Manual queue: pended READ_REPORT requests are completed by the timer.
    // SAFETY: zeroed config then fields set.
    let mut mcfg: WDF_IO_QUEUE_CONFIG = unsafe { core::mem::zeroed() };
    mcfg.Size = core::mem::size_of::<WDF_IO_QUEUE_CONFIG>() as ULONG;
    mcfg.DispatchType = WdfIoQueueDispatchManual;
    mcfg.PowerManaged = WdfUseDefault;
    let mut manual_queue: WDFQUEUE = core::ptr::null_mut();
    // SAFETY: device + config valid; attributes null; queue receives the handle.
    let st = unsafe {
        call_unsafe_wdf_function_binding!(
            WdfIoQueueCreate,
            device,
            &mut mcfg,
            WDF_NO_OBJECT_ATTRIBUTES,
            &mut manual_queue
        )
    };
    if !nt_success(st) {
        dbglog!("[pf-ds] manual WdfIoQueueCreate failed 0x{:08x}", st as u32);
        return st;
    }
    MANUAL_QUEUE.store(manual_queue, Ordering::SeqCst);

    // Periodic timer (parent = manual queue) completes pended reads with the neutral report.
    // SAFETY: zeroed config then fields set.
    let mut tcfg: WDF_TIMER_CONFIG = unsafe { core::mem::zeroed() };
    tcfg.Size = core::mem::size_of::<WDF_TIMER_CONFIG>() as ULONG;
    tcfg.EvtTimerFunc = Some(evt_timer);
    tcfg.Period = 8; // ms
    tcfg.AutomaticSerialization = 1; // TRUE — UMDF requires a serialized timer (vhidmini2 pattern)
    // SAFETY: a zeroed WDF_OBJECT_ATTRIBUTES is a valid all-null attributes struct; we set Size + the
    // fields we use below.
    let mut tattr: WDF_OBJECT_ATTRIBUTES = unsafe { core::mem::zeroed() };
    tattr.Size = core::mem::size_of::<WDF_OBJECT_ATTRIBUTES>() as ULONG;
    tattr.ParentObject = manual_queue.cast();
    // mem::zeroed leaves these at 0 (Invalid) → set them like WDF_OBJECT_ATTRIBUTES_INIT
    // (matches the working vhidmini2 UMDF timer setup; avoids 0xc0200209 / 0xc00000bb).
    tattr.ExecutionLevel = WdfExecutionLevelInheritFromParent;
    tattr.SynchronizationScope = WdfSynchronizationScopeInheritFromParent;
    let mut timer: WDFTIMER = core::ptr::null_mut();
    // SAFETY: config + attributes valid; timer receives the handle.
    let st = unsafe {
        call_unsafe_wdf_function_binding!(WdfTimerCreate, &mut tcfg, &mut tattr, &mut timer)
    };
    if !nt_success(st) {
        dbglog!("[pf-ds] WdfTimerCreate failed 0x{:08x}", st as u32);
        return st;
    }
    // SAFETY: timer valid; -80000 == 8ms relative due time (100ns units, negative = relative).
    let _started = unsafe { call_unsafe_wdf_function_binding!(WdfTimerStart, timer, -80000i64) };

    log("[pf-ds] device ready (DualSense 054C:0CE6)");
    STATUS_SUCCESS
}

extern "C" fn evt_io_device_control(
    _queue: WDFQUEUE,
    request: WDFREQUEST,
    _output_len: usize,
    _input_len: usize,
    ioctl: ULONG,
) {
    // SAFETY: `request` is the live request for THIS EvtIoDeviceControl invocation — exactly the
    // contract `Request::new` requires. Everything after is safe (the token owns completion).
    let request = unsafe { Request::new(request) };

    // Skip the 8ms READ_REPORT cadence so the log stays readable during a game test;
    // the 0x02 OUTPUT report (the gate) and the descriptor handshake still log.
    if ioctl != IOCTL_HID_READ_REPORT {
        dbglog!("[pf-ds] ioctl 0x{ioctl:08x} out={_output_len} in={_input_len}");
    }

    // READ_REPORT forwards to the manual queue (the timer completes it) — this CONSUMES the request
    // token, so it's handled apart from the status-and-complete paths below.
    if ioctl == IOCTL_HID_READ_REPORT {
        let mq: WDFQUEUE = MANUAL_QUEUE.load(Ordering::SeqCst);
        // SAFETY: `mq` is the manual queue created in EvtDeviceAdd (a live WDFQUEUE of this device).
        match unsafe { request.forward_to_queue(mq) } {
            Ok(()) => {}                        // framework owns it now (completed by the timer)
            Err((req, st)) => req.complete(st), // forward failed → complete with the error
        }
        return;
    }

    let status: NTSTATUS = match ioctl {
        IOCTL_HID_GET_DEVICE_DESCRIPTOR => request.copy_to_output(match device_type() {
            1 => &DS4_HID_DESC,
            2 => &EDGE_HID_DESC,
            3 => &DECK_HID_DESC,
            _ => &HID_DESC,
        }),
        IOCTL_HID_GET_DEVICE_ATTRIBUTES => request.copy_to_output(&hid_attrs(device_type())),
        IOCTL_HID_GET_REPORT_DESCRIPTOR => request.copy_to_output(match device_type() {
            1 => &DS4_RDESC[..],
            2 => &DS_EDGE_RDESC[..],
            3 => &DECK_RDESC[..],
            _ => &DUALSENSE_RDESC[..],
        }),
        IOCTL_HID_WRITE_REPORT | IOCTL_UMDF_HID_SET_OUTPUT_REPORT => {
            on_output_report(&request, ioctl)
        }
        IOCTL_UMDF_HID_SET_FEATURE => on_set_feature(&request),
        IOCTL_UMDF_HID_GET_FEATURE => on_get_feature(&request),
        IOCTL_UMDF_HID_GET_INPUT_REPORT => request.copy_to_output(&neutral_report(device_type())),
        IOCTL_HID_GET_STRING => on_get_string(&request),
        _ => STATUS_NOT_IMPLEMENTED,
    };

    dbglog!("[pf-ds] ioctl 0x{ioctl:08x} -> 0x{:08x}", status as u32);
    request.complete(status);
}

// The 0x02 gate: a game writing an output report (rumble / lightbar / ADAPTIVE TRIGGERS). Per the
// UMDF marshalling convention the report data is the *input* buffer and the report id is carried in
// the *output* buffer length. We log it, then publish it to the DATA section for the host.
fn on_output_report(request: &Request, ioctl: ULONG) -> NTSTATUS {
    let (bytes, inlen) = match request.input_bytes(64) {
        Ok(v) => v,
        Err(st) => return st,
    };
    let report_id = request.output_buffer_len() as u32; // report id, UMDF convention

    let mut hex = String::new();
    for b in bytes.iter().take(48) {
        hex.push_str(&format!("{b:02x} "));
    }
    let kind = if ioctl == IOCTL_HID_WRITE_REPORT {
        "WRITE_REPORT"
    } else {
        "SET_OUTPUT_REPORT"
    };
    dbglog!("[pf-ds] *** OUTPUT {kind} reportId={report_id} len={inlen} data: {hex}");

    // Publish the game's 0x02 output report to the sealed DATA section for the host (rumble /
    // lightbar / player-LEDs / adaptive triggers): legacy slot + seq, plus the v2.1 ring.
    if !bytes.is_empty()
        && let Some(view) = CHANNEL.data()
    {
        publish_output(view, &bytes);
    }

    request.set_information(inlen as u64);
    STATUS_SUCCESS
}

/// Deck identity: the last SET_FEATURE payload (the Steam command byte + args, minus the
/// report-id prefix). Steam's Deck contract is command-in-SET_FEATURE → answer-in-GET_FEATURE
/// on the one unnumbered feature report; the PS identities ignore this (their SET_FEATUREs are
/// fire-and-forget) — acking them is all they need.
static LAST_SET_FEATURE: std::sync::Mutex<[u8; 64]> = std::sync::Mutex::new([0; 64]);

// SET_FEATURE: ack (the PS identities' contract), latch the payload for the Deck's GET_FEATURE
// answer, and — the Deck feedback path — publish Steam's rumble/haptic commands to the host.
// Per the UMDF marshalling convention the report data is the input buffer.
fn on_set_feature(request: &Request) -> NTSTATUS {
    if let Ok((bytes, _)) = request.input_bytes(64) {
        // The wire carries [report-id 0, cmd, …] for the unnumbered Steam report; store the
        // command-first view. (PS set-features carry their own report id first — harmless.)
        let src: &[u8] = if bytes.first() == Some(&0x00) && bytes.len() > 1 {
            &bytes[1..]
        } else {
            &bytes
        };
        if let Ok(mut g) = LAST_SET_FEATURE.lock() {
            g.fill(0);
            let n = src.len().min(64);
            g[..n].copy_from_slice(&src[..n]);
        }
        // Deck feedback: Steam drives rumble (0xEB) and trackpad haptic pulses (0x8F) via
        // SET_FEATURE on the unnumbered report — the PS identities get theirs as OUTPUT
        // reports instead. Publish them to the host through the same output slot + seq the
        // output path uses, re-prefixed with the report-id 0 byte so the host's
        // `parse_steam_output` sees the exact wire shape the Linux UHID path delivers.
        if device_type() == 3
            && matches!(src.first(), Some(&0xEB) | Some(&0x8F))
            && let Some(view) = CHANNEL.data()
        {
            let mut out = [0u8; 64];
            let n = src.len().min(63);
            out[1..1 + n].copy_from_slice(&src[..n]);
            publish_output(view, &out);
        }
    }
    dbglog!("[pf-ds] SET_FEATURE (acked, latched for GET)");
    STATUS_SUCCESS
}

/// Deck identity: build the GET_FEATURE reply from the latched SET_FEATURE command — the
/// 0x83 GET_ATTRIBUTES 9-attribute blob (unit id keyed per pad) or the 0xAE unit serial, both
/// captured from a physical Deck (see inject/proto/steam_proto.rs feature_reply, the source of
/// truth this mirrors). Anything else echoes the latched command.
fn deck_feature_reply() -> [u8; 64] {
    let last = LAST_SET_FEATURE.lock().map(|g| *g).unwrap_or([0u8; 64]);
    // Per-pad unit id "PF" + the pad index the host stamped into the section — matches
    // steam_proto::deck_unit_id / deck_serial, so two virtual Decks never collide in Steam's eyes.
    let unit_id: u32 = 0x5046_0000 | pad_index() as u32;
    // Steam validates the unit serial's PREFIX before accepting it: a "PF"-leading serial is
    // REJECTED ("Invalid or missing unit serial number …") and Steam then substitutes a hash and
    // MANGLES the displayed name ("Steam Deck Controllerggg"). An 'F'-leading serial passes, so we
    // keep our PunktFunk marker one slot in ("FVPF") — still distinct enough for the Linux side's
    // physical-Deck self-detection while satisfying Steam's format check. (This, not the build-time
    // attributes below, is what un-mangles the name — verified by A/B on .173.)
    let unit_serial = format!("FVPF{unit_id:08X}");
    let unit_serial = unit_serial.as_bytes();
    let mut r = [0u8; 64];
    match last[0] {
        0x83 => {
            // GET_ATTRIBUTES_VALUES: [0x83, 0x2d, then 9x (attr-id, value u32-LE)].
            r[0] = 0x83;
            r[1] = 0x2D;
            // Attribute semantics per SDL's controller_constants.h: 0x04 = FIRMWARE_BUILD_TIME
            // and 0x0A = BOOTLOADER_BUILD_TIME are unix timestamps that must look like real build
            // dates (the old unit-id-derived junk here was cosmetic; the name mangling was the
            // serial prefix). Uniqueness rides the serial.
            let attrs: [(u8, u32); 9] = [
                (0x01, 0x1205),      // ATTRIB_PRODUCT_ID
                (0x02, 0),           // ATTRIB_CAPABILITIES
                (0x0A, 0x6408_9000), // ATTRIB_BOOTLOADER_BUILD_TIME (2023-03-08)
                (0x04, 0x66A8_C000), // ATTRIB_FIRMWARE_BUILD_TIME (2024-07-30)
                (0x09, 0x2E),        // ATTRIB_BOARD_REVISION (captured)
                (0x0B, 0x0FA0),      // ATTRIB_CONNECTION_INTERVAL_IN_US (4 ms)
                (0x0D, 0),
                (0x0C, 0),
                (0x0E, 0),
            ];
            let mut o = 2;
            for (id, val) in attrs {
                r[o] = id;
                r[o + 1..o + 5].copy_from_slice(&val.to_le_bytes());
                o += 5;
            }
        }
        0xAE => {
            // GET_STRING_ATTRIBUTE: [0xAE, len, attr, ascii…]. Steam requests two strings: attr
            // 0x00 = ATTRIB_STR_BOARD_SERIAL (the PCB serial) and 0x01 = ATTRIB_STR_UNIT_SERIAL.
            // Echo the exact attr requested (last[2]) — the unit serial is the one that matters:
            // getting its format right (FVPF…, see above) is what un-mangles the displayed name.
            // Steam ALSO validates the PCB serial against a Valve-internal format we don't have a
            // real capture of; it logs "Deck Controller PCB Serial# invalid" for ANY value we send
            // (including an empty one — verified on .173), but that line is BENIGN: unlike a bad
            // unit serial, it does not mangle the name, change the handle, or block promotion. So we
            // serve the unit serial for both attrs and accept the log.
            r[0] = 0xAE;
            r[1] = unit_serial.len() as u8;
            r[2] = last[2];
            r[3..3 + unit_serial.len()].copy_from_slice(unit_serial);
        }
        _ => r.copy_from_slice(&last),
    }
    r
}

// GET_FEATURE: report id from the input buffer; reply with the matching DualSense/DualShock 4 blob
// (the Deck identity instead answers the latched Steam command — its one feature report is
// unnumbered).
fn on_get_feature(request: &Request) -> NTSTATUS {
    if device_type() == 3 {
        return request.copy_to_output(&deck_feature_reply());
    }
    let (bytes, _) = match request.input_bytes(1) {
        Ok(v) => v,
        Err(st) => return st,
    };
    let Some(&report_id) = bytes.first() else {
        return STATUS_INVALID_PARAMETER;
    };
    // DualSense + Edge use feature ids 0x05/0x09/0x20 (same blobs — SDL forces enhanced-rumble
    // for the Edge PID regardless of the firmware version at 0x20[44..46]); DualShock 4 uses
    // 0x02/0x12/0xa3.
    // The pairing replies are per-pad: the MAC (bytes 1..7, LSB first) low octet carries the pad
    // index (see `pad_index` — SDL/Steam dedup controllers by this serial), agreeing with the
    // GET_STRING serial in `on_get_string`. The Edge lands on its GET_STRING base (0x75 = DS
    // base + 1) so its feature MAC and USB serial string agree too.
    let devtype = device_type();
    let mut ds_pairing = DS_FEATURE_PAIRING;
    ds_pairing[1] = ds_pairing[1]
        .wrapping_add(u8::from(devtype == 2))
        .wrapping_add(pad_index());
    let mut ds4_pairing = DS4_FEATURE_PAIRING;
    ds4_pairing[1] = ds4_pairing[1].wrapping_add(pad_index());
    let blob: &[u8] = match (devtype, report_id) {
        (0 | 2, 0x05) => &DS_FEATURE_CALIBRATION,
        (0 | 2, 0x09) => &ds_pairing,
        (0 | 2, 0x20) => &DS_FEATURE_FIRMWARE,
        (1, 0x02) => &DS4_FEATURE_CALIBRATION,
        (1, 0x12) => &ds4_pairing,
        (1, 0xA3) => &DS4_FEATURE_FIRMWARE,
        (_, other) => {
            dbglog!("[pf-ds] GET_FEATURE unknown report id 0x{other:02x}");
            return STATUS_INVALID_PARAMETER;
        }
    };
    request.copy_to_output(blob)
}

// IOCTL_HID_GET_STRING: the input is a ULONG whose low word is the string id and whose high word is
// the language id. Reply with the requested device string as a NUL-terminated UTF-16 buffer. Native
// PS5 / Steam code reads these (HidD_GetProductString / HidD_GetSerialNumberString — the serial is one
// way they tell USB from BT). Observed live: Windows polls ids 0x0E/0x0F/0x10 (lang 0x0409)
// cyclically — the manufacturer/product/serial slots — NOT the 0/1/2 HID_STRING_ID_* constants; both.
fn on_get_string(request: &Request) -> NTSTATUS {
    let (bytes, _) = match request.input_bytes(4) {
        Ok(v) => v,
        Err(st) => return st,
    };
    let id_val: u32 = if bytes.len() >= 4 {
        u32::from_le_bytes([bytes[0], bytes[1], bytes[2], bytes[3]])
    } else {
        0
    };
    let string_id = id_val & 0xFFFF;
    let devtype = device_type();
    dbglog!("[pf-ds] GET_STRING id=0x{string_id:04x} (raw 0x{id_val:08x}) devtype={devtype}");
    let s: String = match string_id {
        0 | 0x000e => match devtype {
            1 => "Sony Computer Entertainment".into(),
            3 => "Valve Software".into(),
            _ => "Sony Interactive Entertainment".into(),
        },
        // Per-pad serials (see `pad_index`): SDL reads this via HidD_GetSerialNumberString and
        // Steam dedups controllers by it. The PS strings are the pairing MAC MSB-first, so the
        // low octet — the LAST two hex chars — carries the pad index, agreeing with the patched
        // feature 0x09/0x12 replies in `on_get_feature`. The Deck serial must agree with
        // deck_feature_reply's 0xAE answer (Steam reads both).
        2 | 0x0010 => match devtype {
            1 => format!("DEADBEEF00{:02X}", 0x01u8.wrapping_add(pad_index())),
            2 => format!("35533AD6E7{:02X}", 0x75u8.wrapping_add(pad_index())),
            3 => format!("FVPF{:08X}", 0x5046_0000u32 | pad_index() as u32),
            _ => format!("35533AD6E7{:02X}", 0x74u8.wrapping_add(pad_index())),
        },
        _ => match devtype {
            1 => "Wireless Controller".into(),
            2 => "DualSense Edge Wireless Controller".into(),
            3 => "Steam Deck Controller".into(),
            _ => "DualSense Wireless Controller".into(),
        },
    };
    let mut wide: Vec<u8> = Vec::with_capacity(s.len() * 2 + 2);
    for u in s.encode_utf16() {
        wide.extend_from_slice(&u.to_le_bytes());
    }
    wide.extend_from_slice(&[0, 0]); // NUL terminator (UTF-16)
    request.copy_to_output(&wide)
}

/// The host's device-type selector from the sealed DATA section (`device_type` @140): 0 = DualSense
/// (default), 1 = DualShock 4, 2 = DualSense Edge, 3 = Steam Deck. Read fresh on each enumeration
/// query — cheap. If
/// the channel hasn't attached when hidclass first asks (the host stamps the section + eager-delivers
/// before `SwDeviceCreate` returns, but the handshake can be a few ms behind), pump the channel
/// briefly — ONCE — for the delivery: a DS4/Edge pad must not enumerate with the default DualSense
/// identity because of a lost race. After that one bounded wait, fall back to the last observed type.
fn device_type() -> u8 {
    if let Some(view) = CHANNEL.data() {
        let t = view.read_u8(OFF_DEVICE_TYPE);
        LAST_DEVTYPE.store(t as u32, Ordering::Relaxed);
        return t;
    }
    if !DEVTYPE_WAITED.swap(true, Ordering::SeqCst) {
        let cfg = channel_cfg();
        for _ in 0..100 {
            if let Some(view) = CHANNEL.pump(&cfg) {
                let t = view.read_u8(OFF_DEVICE_TYPE);
                LAST_DEVTYPE.store(t as u32, Ordering::Relaxed);
                return t;
            }
            std::thread::sleep(std::time::Duration::from_millis(10));
        }
        dbglog!(
            "[pf-ds] device_type: sealed channel not attached within 1s — defaulting to the last observed identity"
        );
    }
    LAST_DEVTYPE.load(Ordering::Relaxed) as u8
}

extern "C" fn evt_timer(timer: WDFTIMER) {
    // One sealed-channel tick: publish our pid / adopt a delivery / detect host-gone, then pull the
    // latest host input report from the attached DATA section (all safe, via pf_umdf_util).
    match CHANNEL.pump(&channel_cfg()) {
        Some(view) => {
            let mut buf = [0u8; 64];
            view.read_bytes(OFF_INPUT, &mut buf);
            if buf[0] == 0x01
                && let Ok(mut g) = INPUT_REPORT.lock()
            {
                *g = buf;
            }
            // Health marks the host watches: driver_proto (attach signal, idempotent) and
            // driver_heartbeat (+1 per ~8 ms tick = liveness). Lets the host tell "driver bound
            // and alive" apart from "driver package missing/failed to bind".
            view.write_u32(OFF_DRIVER_PROTO, GAMEPAD_PROTO_VERSION);
            let hb = view.read_u32(OFF_DRIVER_HEARTBEAT).wrapping_add(1);
            view.write_u32(OFF_DRIVER_HEARTBEAT, hb);
        }
        None => {
            // Host gone (mailbox name vanished) or channel not attached yet: feed games the neutral
            // report instead of a frozen last state (matters for the persistent out-of-band devnode,
            // which outlives host sessions).
            if let Ok(mut g) = INPUT_REPORT.lock() {
                *g = neutral_report(LAST_DEVTYPE.load(Ordering::Relaxed) as u8);
            }
        }
    }

    // Complete the next pended READ_REPORT with the current input report (safe queue/request API).
    // SAFETY: the timer's parent object is the manual queue (set in EvtDeviceAdd); the framework
    // guarantees a live handle here.
    let queue =
        unsafe { call_unsafe_wdf_function_binding!(WdfTimerGetParentObject, timer) } as WDFQUEUE;
    // SAFETY: `queue` is that live manual queue — the exact contract `retrieve_next_request` needs.
    if let Some(request) = unsafe { wdf::retrieve_next_request(queue) } {
        let report = INPUT_REPORT.lock().map(|g| *g).unwrap_or(NEUTRAL_REPORT);
        let st = request.copy_to_output(&report);
        request.complete(st);
    }
}
