//! Passive, behavior-preserving diagnostic traces for FIFA 17's FUT pre-match
//! KIT SELECTOR data flow.
//!
//! RE (2026-08-20, Ghidra on CardsDLL_Win64_retail.dll) established that the
//! pre-match kit selector is fed ENTIRELY client-side (NOT by POW/EASFC):
//!
//!   * `FUT_GET_MATCH_KITS_DP` (id 0x7565) builder `FUN_1800be6a0` (rva 0xbe6a0)
//!     reads a boolean gate `ctx+0x152` (`KITS_AVAILABLE`); when false, or when
//!     the two available-kit vectors are empty, the selector renders blank/white.
//!   * The available home/away kit-id lists live on `FutSquadServiceImpl`
//!     (`this+0xe08` home, `this+0xe38` away) and are written by the setter
//!     `FUN_180196760` (rva 0x96760, vtable slot 0x1d0): args (this, srcVec, side).
//!   * A club KIT ITEM is turned into an available kit by `FUN_1801c3480`
//!     (rva 0x1c3480): it reads item fields (`+0x4c==7`, `+0x60==4`,
//!     `+0x5c`∈{101 home,102 away}, `+0x94` source teamid, `+0xba`
//!     teamkittypetechid) and calls `FUN_1801c44b0` (rva 0x1c44b0) to clone that
//!     team's kit rows from the CLIENT-LOCAL `teamkits` DB into the FUT club
//!     (teamtechid 130000).
//!
//! These traces answer, in one operator-driven match, exactly WHERE the empty
//! selector originates: do kit club items reach the client (kit_item_clone), does
//! the clone into the FUT club happen (kit_db_clone), does the available list get
//! set non-empty (set_available_kits), and what does the selector finally read
//! (get_match_kits: KITS_AVAILABLE + count). Every trace is read-only: it logs,
//! then tail-calls the original through a trampoline. Copied prologues are whole,
//! position-independent instructions (the one rip-relative prologue uses the
//! relocating installer).

use core::sync::atomic::{AtomicUsize, Ordering};

use windows_sys::Win32::System::LibraryLoader::GetModuleHandleA;

use crate::sbc_trace::{readable_range, validate_cards_build};
use crate::season_trace::{install_detour, install_detour_reloc, rd_i32, rd_u8};
use crate::write_log;

static REPORTS: AtomicUsize = AtomicUsize::new(0);

fn budget() -> bool {
    REPORTS.fetch_add(1, Ordering::Relaxed) < 256
}

unsafe fn rd_usize(addr: usize) -> Option<usize> {
    readable_range(addr, 8).then(|| core::ptr::read_volatile(addr as *const usize))
}

// FUT_GET_MATCH_KITS_DP builder FUN_1800be6a0 (0xbe6a0). rcx = DP model ctx.
// ctx+0x152 is the KITS_AVAILABLE bool that gates the whole selector list.
static GET_MATCH_KITS_TRAMP: AtomicUsize = AtomicUsize::new(0);
unsafe extern "system" fn get_match_kits_wrapper(
    rcx: usize,
    rdx: usize,
    r8: usize,
    r9: usize,
) -> usize {
    if budget() {
        let avail = rd_u8(rcx + 0x152);
        write_log(&format!(
            "KIT_GET: FUT_GET_MATCH_KITS_DP ctx={rcx:#x} KITS_AVAILABLE={avail:?}\n"
        ));
    }
    let t = GET_MATCH_KITS_TRAMP.load(Ordering::Acquire);
    if t == 0 {
        return 0;
    }
    let original: unsafe extern "system" fn(usize, usize, usize, usize) -> usize =
        core::mem::transmute(t);
    original(rcx, rdx, r8, r9)
}

// setAvailableKits FUN_180196760 (0x96760): (this, srcVec, side). srcVec is an
// int vector {begin@+0, end@+8}; count = (end-begin)/4. side 0=home, 1=away.
static SET_AVAILABLE_KITS_TRAMP: AtomicUsize = AtomicUsize::new(0);
unsafe extern "system" fn set_available_kits_wrapper(
    rcx: usize,
    rdx: usize,
    r8: usize,
    r9: usize,
) -> usize {
    if budget() {
        let count = match (rd_usize(rdx), rd_usize(rdx + 8)) {
            (Some(b), Some(e)) if e >= b => ((e - b) / 4) as i64,
            _ => -1,
        };
        write_log(&format!(
            "KIT_SET: setAvailableKits this={rcx:#x} side={r8} count={count}\n"
        ));
    }
    let t = SET_AVAILABLE_KITS_TRAMP.load(Ordering::Acquire);
    if t == 0 {
        return 0;
    }
    let original: unsafe extern "system" fn(usize, usize, usize, usize) -> usize =
        core::mem::transmute(t);
    original(rcx, rdx, r8, r9)
}

// Kit-item clone driver FUN_1801c3480 (0x1c3480): rdx = param_2, the club-item
// event; the item struct is at *(param_2+0x10). Logs the fields the function
// branches on so we can see whether a kit club item reaches the client and its
// home/away designator + source teamid.
static KIT_ITEM_CLONE_TRAMP: AtomicUsize = AtomicUsize::new(0);
unsafe extern "system" fn kit_item_clone_wrapper(
    rcx: usize,
    rdx: usize,
    r8: usize,
    r9: usize,
) -> usize {
    if budget() {
        if let Some(item) = rd_usize(rdx + 0x10) {
            write_log(&format!(
                "KIT_ITEM: clone-driver item={item:#x} type[+0x4c]={:?} subid[+0x5c]={:?} \
                 cat[+0x60]={:?} teamid[+0x94]={:?} kittype[+0xba]={:?}\n",
                rd_i32(item + 0x4c),
                rd_i32(item + 0x5c),
                rd_i32(item + 0x60),
                rd_i32(item + 0x94),
                rd_i32(item + 0xba),
            ));
        } else {
            write_log(&format!(
                "KIT_ITEM: clone-driver param_2={rdx:#x} (item ptr unreadable)\n"
            ));
        }
    }
    let t = KIT_ITEM_CLONE_TRAMP.load(Ordering::Acquire);
    if t == 0 {
        return 0;
    }
    let original: unsafe extern "system" fn(usize, usize, usize, usize) -> usize =
        core::mem::transmute(t);
    original(rcx, rdx, r8, r9)
}

// Kit DB clone FUN_1801c44b0 (0x1c44b0): (clubmgr, side, teamtechid, kittype).
// Fires only when the driver decided the item is a home(101)/away(102) kit, so
// this is the proof the FUT-club (teamtechid 130000) kit rows get synthesized.
static KIT_DB_CLONE_TRAMP: AtomicUsize = AtomicUsize::new(0);
unsafe extern "system" fn kit_db_clone_wrapper(
    rcx: usize,
    rdx: usize,
    r8: usize,
    r9: usize,
) -> usize {
    if budget() {
        write_log(&format!(
            "KIT_DBCLONE: clone team kit side={rdx} src_teamtechid={r8} kittype={r9}\n"
        ));
    }
    let t = KIT_DB_CLONE_TRAMP.load(Ordering::Acquire);
    if t == 0 {
        return 0;
    }
    let original: unsafe extern "system" fn(usize, usize, usize, usize) -> usize =
        core::mem::transmute(t);
    original(rcx, rdx, r8, r9)
}

unsafe fn worker() {
    let mut base = 0usize;
    for _ in 0..600u32 {
        base = GetModuleHandleA(c"CardsDLL_Win64_retail.dll".as_ptr().cast()) as usize;
        if base != 0 {
            break;
        }
        std::thread::sleep(std::time::Duration::from_millis(500));
    }
    if base == 0 || !validate_cards_build(base) {
        write_log("KIT_TRACE: CardsDLL unavailable/invalid; kit trace inactive\n");
        return;
    }
    // FUN_1800be6a0: 48 8b c4 55 41 54 41 55 41 56 41 57 48 8d 68 a1 (copy_len 16).
    install_detour(
        base,
        0xbe6a0,
        "GetMatchKits_DP(0xbe6a0)",
        16,
        &[
            0x48, 0x8b, 0xc4, 0x55, 0x41, 0x54, 0x41, 0x55, 0x41, 0x56, 0x41, 0x57, 0x48, 0x8d,
            0x68, 0xa1,
        ],
        get_match_kits_wrapper as *const () as usize,
        &GET_MATCH_KITS_TRAMP,
    );
    // FUN_180196760: 48 89 54 24 10 53 48 83 ec 30 48 c7 44 24 20 fe ff ff ff (copy_len 19).
    install_detour(
        base,
        0x96760,
        "setAvailableKits(0x96760)",
        19,
        &[
            0x48, 0x89, 0x54, 0x24, 0x10, 0x53, 0x48, 0x83, 0xec, 0x30, 0x48, 0xc7, 0x44, 0x24,
            0x20, 0xfe, 0xff, 0xff, 0xff,
        ],
        set_available_kits_wrapper as *const () as usize,
        &SET_AVAILABLE_KITS_TRAMP,
    );
    // FUN_1801c3480: 48 89 5c 24 08 57 48 83 ec 60 <48 8b 05 disp32> (rip-relative
    // MOV RAX,[rip+..] at copied offset 10; disp32 at 13, insn end 17; copy_len 17).
    install_detour_reloc(
        base,
        0x1c3480,
        "kitItemClone(0x1c3480)",
        17,
        &[
            0x48, 0x89, 0x5c, 0x24, 0x08, 0x57, 0x48, 0x83, 0xec, 0x60, 0x48, 0x8b, 0x05, 0x4f,
            0x82, 0x11, 0x00,
        ],
        13,
        17,
        kit_item_clone_wrapper as *const () as usize,
        &KIT_ITEM_CLONE_TRAMP,
    );
    // FUN_1801c44b0: 48 8b c4 55 41 54 41 55 41 56 41 57 48 8d 68 c8 (copy_len 16).
    install_detour(
        base,
        0x1c44b0,
        "kitDbClone(0x1c44b0)",
        16,
        &[
            0x48, 0x8b, 0xc4, 0x55, 0x41, 0x54, 0x41, 0x55, 0x41, 0x56, 0x41, 0x57, 0x48, 0x8d,
            0x68, 0xc8,
        ],
        kit_db_clone_wrapper as *const () as usize,
        &KIT_DB_CLONE_TRAMP,
    );
    write_log("KIT_TRACE: all kit-selector traces armed\n");
}

/// Arm the passive kit-selector diagnostics on a deferred thread (CardsDLL is not
/// yet loaded at DllMain time). Read-only: never changes game behavior.
pub(crate) fn install() {
    write_log("KIT_TRACE: requested; deferred signature validation starting\n");
    std::thread::spawn(|| unsafe { worker() });
}