// coop_input_probe -- standalone harness to bring up the injected XInput hook and
// forward synthetic controller input into a real game, without Steam / RPT / the
// host UI. This is the headless reproduction for the "32-bit game crashes as soon
// as a button is pressed" report: it injects coop_hook.dll, reports one connected
// pad, and toggles a button every second so the game's input layer processes a
// real state change.
//
//   coop_input_probe <pid> [seconds]
//
// Run from the same directory as coop_hook.dll (i.e. bin/<config>/). For a 32-bit
// (WOW64) target it shells out to coop_inject_x86.exe + coop_hook_x86.dll, exactly
// like the host.

#include <algorithm>
#include <cstdio>
#include <cstdlib>
#include <string>

#include <windows.h>

#include "coop/log_ring.hpp"
#include "coop/protocol.hpp"
#include "coop/shared_memory.hpp"

namespace
{

std::wstring dll_path_next_to_self()
{
	wchar_t exe[MAX_PATH] = {};
	GetModuleFileNameW(nullptr, exe, MAX_PATH);
	std::wstring path(exe);
	const size_t slash = path.find_last_of(L"\\/");
	if (slash != std::wstring::npos)
	{
		path.resize(slash + 1);
	}
	return path + L"coop_hook.dll";
}

std::wstring sibling_of(const std::wstring& path, const wchar_t* name)
{
	const size_t slash = path.find_last_of(L"\\/");
	return (slash == std::wstring::npos ? std::wstring() : path.substr(0, slash + 1)) + name;
}

// Inject a 32-bit (WOW64) target via the x86 helper, mirroring the host/audio probe.
bool inject_via_helper(unsigned long pid, const std::wstring& dll_path)
{
	const std::wstring helper = sibling_of(dll_path, L"coop_inject_x86.exe");
	const std::wstring x86_dll = sibling_of(dll_path, L"coop_hook_x86.dll");
	if (GetFileAttributesW(helper.c_str()) == INVALID_FILE_ATTRIBUTES ||
	    GetFileAttributesW(x86_dll.c_str()) == INVALID_FILE_ATTRIBUTES)
	{
		std::printf("ERROR: x86 helper/dll missing next to the probe.\n");
		return false;
	}
	std::wstring cmd = L"\"" + helper + L"\" " + std::to_wstring(pid) + L" \"" + x86_dll + L"\"";
	std::printf("32-bit target: injecting coop_hook_x86.dll via coop_inject_x86.exe ...\n");
	STARTUPINFOW si{};
	si.cb = sizeof(si);
	PROCESS_INFORMATION pi{};
	if (!CreateProcessW(helper.c_str(), cmd.data(), nullptr, nullptr, FALSE, 0, nullptr, nullptr, &si, &pi))
	{
		std::printf("ERROR: CreateProcess(coop_inject_x86) failed (%lu).\n", GetLastError());
		return false;
	}
	WaitForSingleObject(pi.hProcess, INFINITE);
	DWORD code = 1;
	GetExitCodeProcess(pi.hProcess, &code);
	CloseHandle(pi.hThread);
	CloseHandle(pi.hProcess);
	if (code != 0)
	{
		std::printf("ERROR: coop_inject_x86 reported failure (exit %lu).\n", code);
		return false;
	}
	return true;
}

bool inject(unsigned long pid, const std::wstring& dll_path)
{
	if (GetFileAttributesW(dll_path.c_str()) == INVALID_FILE_ATTRIBUTES)
	{
		std::printf("ERROR: coop_hook.dll not found at the probe's directory.\n");
		return false;
	}
	const DWORD access = PROCESS_CREATE_THREAD | PROCESS_QUERY_INFORMATION | PROCESS_VM_OPERATION |
	                     PROCESS_VM_WRITE | PROCESS_VM_READ;
	HANDLE process = OpenProcess(access, FALSE, pid);
	if (process == nullptr)
	{
		std::printf("ERROR: OpenProcess(%lu) failed (%lu). Run as administrator?\n", pid, GetLastError());
		return false;
	}

	USHORT proc_machine = IMAGE_FILE_MACHINE_UNKNOWN, native_machine = IMAGE_FILE_MACHINE_UNKNOWN;
	if (IsWow64Process2(process, &proc_machine, &native_machine) && proc_machine != IMAGE_FILE_MACHINE_UNKNOWN)
	{
		CloseHandle(process);
		return inject_via_helper(pid, dll_path);
	}
	const SIZE_T bytes = (dll_path.size() + 1) * sizeof(wchar_t);
	void* remote = VirtualAllocEx(process, nullptr, bytes, MEM_COMMIT | MEM_RESERVE, PAGE_READWRITE);
	bool ok = false;
	if (remote != nullptr && WriteProcessMemory(process, remote, dll_path.c_str(), bytes, nullptr))
	{
		auto load_library = reinterpret_cast<LPTHREAD_START_ROUTINE>(
		    GetProcAddress(GetModuleHandleW(L"kernel32.dll"), "LoadLibraryW"));
		HANDLE thread = CreateRemoteThread(process, nullptr, 0, load_library, remote, 0, nullptr);
		if (thread != nullptr)
		{
			WaitForSingleObject(thread, INFINITE);
			DWORD exit_code = 0;
			GetExitCodeThread(thread, &exit_code);
			CloseHandle(thread);
			ok = (exit_code != 0);
		}
	}
	if (remote != nullptr)
	{
		VirtualFreeEx(process, remote, 0, MEM_RELEASE);
	}
	CloseHandle(process);
	if (!ok)
	{
		std::printf("ERROR: injection failed (%lu).\n", GetLastError());
	}
	return ok;
}

} // namespace

int wmain(int argc, wchar_t** argv)
{
	if (argc < 2)
	{
		std::printf("usage: coop_input_probe <pid> [seconds] [disable_mask]\n"
		            "  Injects coop_hook.dll, reports one connected pad, and toggles a\n"
		            "  button every second so the game processes a real state change.\n"
		            "  disable_mask (hex): bit per subsystem NOT to install --\n"
		            "    0x1=input 0x2=focus 0x4=audio 0x8=video (default 0 = all on).\n");
		return 1;
	}
	const unsigned long pid = std::wcstoul(argv[1], nullptr, 10);
	const int seconds = (argc >= 3) ? std::max(1, _wtoi(argv[2])) : 30;
	const unsigned disable_mask = (argc >= 4) ? std::wcstoul(argv[3], nullptr, 0) : 0u;
	if (pid == 0)
	{
		std::printf("ERROR: invalid pid.\n");
		return 1;
	}

	// 1) Input SharedBlock: report one connected pad up front (buttons still zero),
	//    so the game sees a controller arrive before we start pressing anything.
	coop::SharedMemory ipc;
	if (!ipc.create(coop::shared_memory_name(pid), sizeof(coop::SharedBlock)))
	{
		std::printf("ERROR: create input mapping failed (%lu).\n", GetLastError());
		return 1;
	}
	auto* block = ipc.as<coop::SharedBlock>();
	block->version = coop::kProtocolVersion;
	block->sequence.store(0, std::memory_order_relaxed);

	// Subsystem isolation: skip installing the ones whose bit is set in disable_mask
	// (0x1=input 0x2=focus 0x4=audio 0x8=video). Lets us bisect which injected
	// subsystem freezes a given game.
	static const char* kSubsysNames[] = {"input", "focus", "audio", "video"};
	for (std::uint32_t i = 0; i < coop::HookSubsys_Count; ++i)
	{
		const bool disabled = (disable_mask & (1u << i)) != 0;
		block->control.subsystem_disabled[i].store(disabled ? 1u : 0u, std::memory_order_release);
		std::printf("subsystem %-6s %s\n", kSubsysNames[i], disabled ? "DISABLED" : "on");
	}

	coop::CoopPadState pads[coop::kMaxPads] = {};
	pads[0].connected = 1;
	pads[0].packet = 1;
	coop::publish_pads(*block, pads, coop::kMaxPads);
	block->magic = coop::kProtocolMagic;

	// Log ring (host's role) so the hook streams its trace back to us.
	coop::SharedMemory log_shm;
	coop::LogRing* log_ring = nullptr;
	std::uint64_t log_cursor = 0;
	if (log_shm.create(coop::log_ring_name(pid), coop::log_ring_total_size(coop::kLogCapacity)))
	{
		log_ring = log_shm.as<coop::LogRing>();
		coop::log_ring_init(*log_ring, coop::kLogCapacity);
	}

	// Enable the hook's file trace for this session.
	{
		wchar_t dir[MAX_PATH] = {};
		if (GetTempPathW(MAX_PATH, dir) != 0)
		{
			const std::wstring sentinel = std::wstring(dir) + L"coop_hook.log.on";
			HANDLE h = CreateFileW(sentinel.c_str(), GENERIC_WRITE, FILE_SHARE_READ, nullptr, OPEN_ALWAYS,
			                       FILE_ATTRIBUTE_NORMAL, nullptr);
			if (h != INVALID_HANDLE_VALUE)
			{
				CloseHandle(h);
			}
		}
	}

	std::printf("Injecting coop_hook.dll into pid %lu ...\n", pid);
	if (!inject(pid, dll_path_next_to_self()))
	{
		return 1;
	}
	std::printf("Injected. Reporting pad 0 connected; toggling button A each second for %d s.\n", seconds);
	std::printf("Hook trace: %%TEMP%%\\coop_hook.log\n\n");

	const coop::HookStatus& status = block->status;
	for (int t = 0; t < seconds; ++t)
	{
		// Toggle A (0x1000) every other second so the game's input layer sees a real
		// edge -- this is the "press a button" event the crash report points at.
		const bool press = (t % 2) == 1;
		pads[0].packet = static_cast<std::uint32_t>(t + 2);
		pads[0].buttons = press ? 0x1000 : 0x0000;
		pads[0].thumb_lx = press ? 20000 : 0;
		coop::publish_pads(*block, pads, coop::kMaxPads);

		Sleep(1000);

		const std::uint32_t heartbeat = status.heartbeat.load(std::memory_order_relaxed);
		const std::uint32_t attached = status.attached;
		const std::uint64_t gs0 = status.get_state_calls[0].load(std::memory_order_relaxed);
		const std::uint64_t gc0 = status.get_caps_calls[0].load(std::memory_order_relaxed);
		std::printf("[%2ds] %s hb=%u attached=%u getstate[0]=%llu getcaps[0]=%llu buttons=0x%04X\n", t + 1,
		            press ? "A-DOWN" : "A-up  ", heartbeat, attached, static_cast<unsigned long long>(gs0),
		            static_cast<unsigned long long>(gc0), pads[0].buttons);

		// Surface the hook's log lines as they arrive (shows where it got to).
		if (log_ring != nullptr)
		{
			coop::log_ring_drain(*log_ring, log_cursor,
			                     [](const coop::LogRecord& rec) { std::printf("        | %s\n", rec.text); });
		}
	}

	std::printf("\nInstalled hooks (%u):\n", status.hook_entry_count);
	static const char* kSubsys[] = {"Input", "Focus", "Audio", "Video"};
	for (std::uint32_t i = 0; i < status.hook_entry_count && i < coop::kMaxHookEntries; ++i)
	{
		const coop::HookEntry& e = status.hook_entries[i];
		std::printf("  [%-5s] %-34s %s  calls=%llu\n", e.subsystem < 4 ? kSubsys[e.subsystem] : "?", e.name,
		            e.installed ? "ON " : "off", static_cast<unsigned long long>(e.calls));
	}

	std::printf("\nDone. Leaving the hook loaded in the game.\n");
	block->magic = 0;
	return 0;
}