"""patch_freeobject_v2.py <pid> [--revert]

v2 patch: force DBOCache::FreeObject to always take the DELETE path
(never add to freelist). This causes every Release-to-refcount-1 to
invoke the proper destructor, which calls operator delete[] on the
Palette ARGB buffer (and similar for other DBObj-derived classes).

Target byte: EoR 0x004169bf
Original:    0x74  (jz delete_path)
Patched:     0xeb  (jmp delete_path)  — unconditional

Effect:
  - DBOCache::FreeObject(this, obj) now always:
    obj->ReleaseSubObjects(); obj->in_use = 0; this->vt[0x44](obj);
  - Skips the "if freelist enabled, push to freelist" branch
  - Affects ALL DBObj-derived classes (not just Palette)

Risk:
  - Performance: cache misses now require full alloc + load instead of
    reuse from freelist. For frequently-used classes, may add latency.
  - Correctness: should be safe — delete path uses proper destructor
    that already handles all field cleanup.
"""
import ctypes, ctypes.wintypes as wt, sys

TARGET_ADDR  = 0x004169bf
EXPECTED_VAL = 0x74    # jz
PATCHED_VAL  = 0xeb    # jmp

PROCESS_VM_READ           = 0x0010
PROCESS_VM_WRITE          = 0x0020
PROCESS_VM_OPERATION      = 0x0008
PROCESS_QUERY_INFORMATION = 0x0400
PAGE_EXECUTE_READWRITE    = 0x40

k32 = ctypes.windll.kernel32
OpenProcess        = k32.OpenProcess
OpenProcess.argtypes = [wt.DWORD, wt.BOOL, wt.DWORD]; OpenProcess.restype = wt.HANDLE
CloseHandle        = k32.CloseHandle
CloseHandle.argtypes = [wt.HANDLE]; CloseHandle.restype = wt.BOOL
ReadProcessMemory  = k32.ReadProcessMemory
ReadProcessMemory.argtypes = [wt.HANDLE, wt.LPCVOID, wt.LPVOID, ctypes.c_size_t,
                              ctypes.POINTER(ctypes.c_size_t)]
ReadProcessMemory.restype = wt.BOOL
WriteProcessMemory = k32.WriteProcessMemory
WriteProcessMemory.argtypes = [wt.HANDLE, wt.LPVOID, wt.LPCVOID, ctypes.c_size_t,
                               ctypes.POINTER(ctypes.c_size_t)]
WriteProcessMemory.restype = wt.BOOL
VirtualProtectEx   = k32.VirtualProtectEx
VirtualProtectEx.argtypes = [wt.HANDLE, wt.LPVOID, ctypes.c_size_t,
                             wt.DWORD, ctypes.POINTER(wt.DWORD)]
VirtualProtectEx.restype = wt.BOOL


def main():
    if len(sys.argv) < 2:
        print("usage: patch_freeobject_v2.py <pid> [--revert]"); sys.exit(1)
    pid    = int(sys.argv[1])
    revert = "--revert" in sys.argv

    h = OpenProcess(PROCESS_VM_READ|PROCESS_VM_WRITE|PROCESS_VM_OPERATION|PROCESS_QUERY_INFORMATION,
                    False, pid)
    if not h:
        print(f"OpenProcess({pid}) failed: err={ctypes.get_last_error()}"); sys.exit(2)

    cur = ctypes.c_ubyte(0); sz = ctypes.c_size_t(0)
    if not ReadProcessMemory(h, TARGET_ADDR, ctypes.byref(cur), 1, ctypes.byref(sz)):
        print(f"read failed: err={ctypes.get_last_error()}"); CloseHandle(h); sys.exit(3)
    print(f"PID {pid}  byte @ 0x{TARGET_ADDR:08x} current: 0x{cur.value:02x}")

    target = EXPECTED_VAL if revert else PATCHED_VAL
    expect_before = PATCHED_VAL if revert else EXPECTED_VAL

    if cur.value == target:
        print(f"  already {'reverted' if revert else 'patched'}")
        CloseHandle(h); return
    if cur.value != expect_before:
        print(f"  UNEXPECTED current value (wanted 0x{expect_before:02x}) — aborting")
        CloseHandle(h); sys.exit(4)

    old_prot = wt.DWORD(0)
    if not VirtualProtectEx(h, TARGET_ADDR, 1, PAGE_EXECUTE_READWRITE, ctypes.byref(old_prot)):
        print(f"VirtualProtectEx failed: err={ctypes.get_last_error()}"); CloseHandle(h); sys.exit(5)
    new = ctypes.c_ubyte(target)
    if not WriteProcessMemory(h, TARGET_ADDR, ctypes.byref(new), 1, ctypes.byref(sz)):
        print(f"write failed: err={ctypes.get_last_error()}"); CloseHandle(h); sys.exit(6)
    restored = wt.DWORD(0)
    VirtualProtectEx(h, TARGET_ADDR, 1, old_prot.value, ctypes.byref(restored))

    ReadProcessMemory(h, TARGET_ADDR, ctypes.byref(cur), 1, ctypes.byref(sz))
    print(f"  new value:   0x{cur.value:02x}  ({'reverted' if revert else 'patched'})")
    CloseHandle(h)


if __name__ == "__main__":
    main()