package com.xcong.excoin.modules.gateApi;

import io.gate.gateapi.ApiClient;
import io.gate.gateapi.GateApiException;
import io.gate.gateapi.api.FuturesApi;
import io.gate.gateapi.models.FuturesInitialOrder;
import io.gate.gateapi.models.FuturesOrder;
import io.gate.gateapi.models.FuturesPriceTrigger;
import io.gate.gateapi.models.FuturesPriceTriggeredOrder;
import io.gate.gateapi.models.TriggerOrderResponse;
import lombok.extern.slf4j.Slf4j;

import java.math.BigDecimal;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;

/**
 * Gate REST API 执行器。
 *
 * <h3>设计目的</h3>
 * WebSocket 消息在回调线程中处理（如 {@code WebSocketClient} 的 {@code onMessage} 线程）。
 * 下单 REST API 调用可能耗时数百毫秒，若同步执行会阻塞 WS 回调线程，导致心跳超时误判。
 * 本类将所有 REST 调用提交到独立线程池异步执行。
 *
 * <h3>线程模型</h3>
 * 单线程 ThreadPoolExecutor + 有界队列 64 + CallerRunsPolicy：
 * <ul>
 *   <li><b>单线程</b>：保证下单顺序（开多→开空→止盈单），避免并发竞争</li>
 *   <li><b>有界队列 64</b>：防止堆积。极端行情下最多累积 64 个任务</li>
 *   <li><b>CallerRunsPolicy</b>：队列满时由提交线程直接同步执行，形成自然背压</li>
 *   <li><b>allowCoreThreadTimeOut</b>：60s 空闲后线程回收，不浪费资源</li>
 * </ul>
 *
 * <h3>调用链</h3>
 * <pre>
 *   GateGridTradeService.onKline → executor.openLong/openShort → REST API
 *   GateGridTradeService.onPositionUpdate → executor.openLong/openShort → REST API
 *   (每一次开仓后) → executor.placeTakeProfit → REST API
 * </pre>
 *
 * @author Administrator
 */
@Slf4j
public class GateTradeExecutor {

    private static final String SETTLE = "usdt";

    private final FuturesApi futuresApi;
    private final String contract;

    /** 交易线程池：单线程 + 有界队列 + 背压策略 */
    private final ExecutorService executor;

    public GateTradeExecutor(ApiClient apiClient, String contract) {
        this.futuresApi = new FuturesApi(apiClient);
        this.contract = contract;
        this.executor = new ThreadPoolExecutor(
                1, 1,
                60L, TimeUnit.SECONDS,
                new LinkedBlockingQueue<>(64),
                r -> {
                    Thread t = new Thread(r, "gate-trade-worker");
                    t.setDaemon(true);
                    return t;
                },
                new ThreadPoolExecutor.CallerRunsPolicy()
        );
        ((ThreadPoolExecutor) executor).allowCoreThreadTimeOut(true);
    }

    /**
     * 优雅关闭：等待 10 秒，超时则强制中断。
     */
    public void shutdown() {
        executor.shutdown();
        try {
            executor.awaitTermination(10, TimeUnit.SECONDS);
        } catch (InterruptedException e) {
            Thread.currentThread().interrupt();
            executor.shutdownNow();
        }
    }

    /**
     * 异步市价开多。quantity 为正数（如 "10"）。
     */
    public void openLong(String quantity, Runnable onSuccess, Runnable onFailure) {
        openPosition(quantity, "t-grid-long", "开多", onSuccess, onFailure);
    }

    /**
     * 异步市价开空。quantity 为负数（如 "-10"）。
     */
    public void openShort(String quantity, Runnable onSuccess, Runnable onFailure) {
        openPosition(quantity, "t-grid-short", "开空", onSuccess, onFailure);
    }

    private void openPosition(String size, String text, String label, Runnable onSuccess, Runnable onFailure) {
        executor.execute(() -> {
            try {
                FuturesOrder order = new FuturesOrder();
                order.setContract(contract);
                order.setSize(size);
                order.setPrice("0");
                order.setTif(FuturesOrder.TifEnum.IOC);
                order.setText(text);
                FuturesOrder result = futuresApi.createFuturesOrder(SETTLE, order, null);
                log.info("[TradeExec] {}成功, 价格:{}, id:{}", label, result.getFillPrice(), result.getId());
                if (onSuccess != null) {
                    onSuccess.run();
                }
            } catch (Exception e) {
                log.error("[TradeExec] {}失败", label, e);
                if (onFailure != null) {
                    onFailure.run();
                }
            }
        });
    }

    /**
     * 异步创建止盈条件单。
     * <p>使用 Gate 的 PriceTriggeredOrder：服务器监控价格，达到触发价后自动平仓。
     * 如果账户已有同方向同规则的条件单（label=UNIQUE），自动清除后重试一次。
     *
     * @param triggerPrice 触发价格
     * @param rule         触发规则（NUMBER_1: ≥ 触发价，NUMBER_2: ≤ 触发价）
     * @param orderType    stop 类型（close-long-position / close-short-position）
     * @param autoSize     双仓平仓方向（close_long / close_short）
     */
    public void placeTakeProfit(BigDecimal triggerPrice,
                                 FuturesPriceTrigger.RuleEnum rule,
                                 String orderType,
                                 String autoSize) {
        executor.execute(() -> {
            FuturesPriceTriggeredOrder order = buildTriggeredOrder(triggerPrice, rule, orderType, autoSize);
            try {
                TriggerOrderResponse response = futuresApi.createPriceTriggeredOrder(SETTLE, order);
                log.info("[TradeExec] 止盈单已创建, 触发价:{}, 类型:{}, id:{}",
                        triggerPrice, orderType, response.getId());
            } catch (GateApiException e) {
                if ("AUTO_USER_EXIST_POSITION_ORDER".equals(e.getErrorLabel())) {
                    log.warn("[TradeExec] 止盈单已存在，清除旧单后重试");
                    try {
                        futuresApi.cancelPriceTriggeredOrderList(SETTLE, contract);
                        TriggerOrderResponse response = futuresApi.createPriceTriggeredOrder(SETTLE, order);
                        log.info("[TradeExec] 止盈单重试成功, 触发价:{}, id:{}", triggerPrice, response.getId());
                    } catch (Exception retryEx) {
                        log.error("[TradeExec] 止盈单重试失败", retryEx);
                    }
                } else {
                    log.error("[TradeExec] 止盈单创建失败, 触发价:{}", triggerPrice, e);
                }
            } catch (Exception e) {
                log.error("[TradeExec] 止盈单创建失败, 触发价:{}", triggerPrice, e);
            }
        });
    }

    /**
     * 异步清除指定合约的所有止盈止损条件单。
     */
    public void cancelAllPriceTriggeredOrders() {
        executor.execute(() -> {
            try {
                futuresApi.cancelPriceTriggeredOrderList(SETTLE, contract);
                log.info("[TradeExec] 已清除所有止盈止损条件单");
            } catch (Exception e) {
                log.error("[TradeExec] 清除止盈止损条件单失败", e);
            }
        });
    }

    /**
     * 构建 FuturesPriceTriggeredOrder 对象。
     * <p>策略=0（价格触发），price_type=0（最新价），expiration=0（永不过期），
     * tif=IOC（立即成交或取消），reduce_only=true（只减仓不开新仓）。
     */
    private FuturesPriceTriggeredOrder buildTriggeredOrder(BigDecimal triggerPrice,
                                                            FuturesPriceTrigger.RuleEnum rule,
                                                            String orderType,
                                                            String autoSize) {
        FuturesPriceTrigger trigger = new FuturesPriceTrigger();
        trigger.setStrategyType(FuturesPriceTrigger.StrategyTypeEnum.NUMBER_0);
        trigger.setPriceType(FuturesPriceTrigger.PriceTypeEnum.NUMBER_0);
        trigger.setPrice(triggerPrice.toString());
        trigger.setRule(rule);
        trigger.setExpiration(0);

        FuturesInitialOrder initial = new FuturesInitialOrder();
        initial.setContract(contract);
        initial.setSize(0L);
        initial.setPrice("0");
        initial.setTif(FuturesInitialOrder.TifEnum.IOC);
        initial.setReduceOnly(true);
        initial.setAutoSize(autoSize);

        FuturesPriceTriggeredOrder order = new FuturesPriceTriggeredOrder();
        order.setTrigger(trigger);
        order.setInitial(initial);
        order.setOrderType(orderType);
        return order;
    }
}