// net_classic_e2e — minimal live probe for the 40250 classic backend.
//
// It intentionally stops after PHASE_GAME.  The login/selection/world burst
// is deterministic and safe to run against a test account; social, storage,
// mall, NPC and cube mutations require a configured account/NPC fixture and
// are driven by the Godot UI or the documented command surface.
//
//   net_classic_e2e <host> <port> <id> <password> [slot] [timeout_seconds]
//
// Exit status 0 means the socket handshake, DH2/CTR negotiation, login,
// character list, character selection and PHASE_GAME were all reached.

#include "../src/net/classic/classic_session.h"

#include <chrono>
#include <cstdio>
#include <cstdlib>
#include <string>
#include <thread>

using steady_clock_t = std::chrono::steady_clock;

static const char *stage_name(mtnet::INetSession::Stage stage) {
	using Stage = mtnet::INetSession::Stage;
	switch (stage) {
		case Stage::Offline: return "offline";
		case Stage::Connecting: return "connecting";
		case Stage::LoggingIn: return "login";
		case Stage::CharSelect: return "char_select";
		case Stage::Loading: return "loading";
		case Stage::InGame: return "in_game";
		case Stage::Failed: return "failed";
	}
	return "unknown";
}

static double elapsed_seconds(steady_clock_t::time_point start) {
	return std::chrono::duration_cast<std::chrono::milliseconds>(steady_clock_t::now() - start)
			.count() /
			1000.0;
}

static int choose_slot(const std::vector<mtnet::classic::CharSlot> &slots, int requested) {
	if (requested >= 0 && requested < (int)slots.size() && !slots[requested].empty()) {
		return requested;
	}
	for (int i = 0; i < (int)slots.size(); ++i) {
		if (!slots[i].empty()) return i;
	}
	return -1;
}

int main(int argc, char **argv) {
	if (argc < 5 || argc > 7) {
		std::fprintf(stderr,
				"usage: %s <host> <port> <id> <password> [slot] [timeout_seconds]\n",
				argv[0]);
		return 64;
	}

	const std::string host = argv[1];
	const int port = std::atoi(argv[2]);
	const std::string id = argv[3];
	const std::string password = argv[4];
	const int requested_slot = argc >= 6 ? std::atoi(argv[5]) : 0;
	const double timeout = argc >= 7 ? std::atof(argv[6]) : 30.0;
	if (port <= 0 || port > 65535 || timeout <= 0.0) {
		std::fprintf(stderr, "invalid port or timeout\n");
		return 64;
	}

	mtnet::classic::ClassicSession session;
	session.set_auto_entergame_delay(1500);
	session.set_wire_trace(std::getenv("MT_NET_TRACE") != nullptr);
	if (!session.connect(host, static_cast<uint16_t>(port), id, password)) {
		std::fprintf(stderr, "FAIL connect: %s\n", session.last_error().c_str());
		return 2;
	}

	std::printf("classic e2e -> %s:%d account=%s requested_slot=%d\n", host.c_str(), port,
			id.c_str(), requested_slot);
	auto start = steady_clock_t::now();
	int last_stage = -1;
	bool selected = false;
	while (elapsed_seconds(start) < timeout) {
		const uint32_t now = static_cast<uint32_t>(elapsed_seconds(start) * 1000.0);
		session.set_now(now);
		session.pump();

		const int current_stage = static_cast<int>(session.stage());
		if (current_stage != last_stage) {
			last_stage = current_stage;
			std::printf("[%.1fs] stage=%s\n", elapsed_seconds(start), stage_name(session.stage()));
		}

		if (session.stage() == mtnet::INetSession::Stage::CharSelect && !selected &&
				session.parser().char_list_ready()) {
			const auto &slots = session.char_slots();
			std::printf("[e2e] character slots=%zu\n", slots.size());
			for (size_t i = 0; i < slots.size(); ++i) {
				const auto &slot = slots[i];
				std::printf("       [%zu] %s id=%u level=%u\n", i, slot.name.c_str(), slot.id,
						slot.level);
			}
			const int slot = choose_slot(slots, requested_slot);
			if (slot < 0) {
				std::fprintf(stderr, "FAIL: account has no selectable character\n");
				session.disconnect();
				return 3;
			}
			if (!session.select_char(slot)) {
				std::fprintf(stderr, "FAIL: select_char(%d)\n", slot);
				session.disconnect();
				return 4;
			}
			std::printf("[e2e] selected slot=%d\n", slot);
			selected = true;
		}

		if (session.stage() == mtnet::INetSession::Stage::Failed) {
			std::fprintf(stderr, "FAIL stage: %s\n", session.last_error().c_str());
			session.disconnect();
			return 5;
		}
		if (session.stage() == mtnet::INetSession::Stage::InGame) {
			const auto &world = session.world();
			int inventory_count = 0;
			for (int cell = 0; cell < mtnet::INVENTORY_MAX_NUM; ++cell) {
				if (!world.inv_slot(cell).empty()) ++inventory_count;
			}
			std::printf("PASS PHASE_GAME main_vid=%u entities=%zu inventory_slots=%d points_level=%d\n",
				world.main_vid(), world.size(), inventory_count, world.points().level());
			session.disconnect();
			return 0;
		}

		std::this_thread::sleep_for(std::chrono::milliseconds(15));
	}

	std::fprintf(stderr, "FAIL timeout after %.1fs at stage=%s: %s\n", timeout,
			stage_name(session.stage()), session.last_error().c_str());
	session.disconnect();
	return 6;
}