package com.xcong.excoin.modules.gateApi;

import io.gate.gateapi.ApiClient;
import io.gate.gateapi.ApiException;
import io.gate.gateapi.GateApiException;
import io.gate.gateapi.api.AccountApi;
import io.gate.gateapi.api.FuturesApi;
import io.gate.gateapi.models.AccountDetail;
import io.gate.gateapi.models.FuturesAccount;
import io.gate.gateapi.models.FuturesPriceTrigger;
import lombok.extern.slf4j.Slf4j;

import java.math.BigDecimal;
import java.math.RoundingMode;

/**
 * Gate 网格交易服务类。使用 Gate SDK 通过 REST API 下单。
 *
 * <h3>状态机</h3>
 * <pre>
 *   WAITING_KLINE → (首次 K 线) → OPENING → ACTIVE
 *                             双开失败 → STOPPED
 *
 *   ACTIVE:
 *     ├─ 仓位 size=0 且方向活跃 → REOPENING_L/S → ACTIVE
 *     │   补仓失败 → 重试 → 仍失败 → STOPPED
 *     └─ cumulativePnl ≥ overallTp 或 ≤ -maxLoss → STOPPED
 * </pre>
 *
 * <h3>架构</h3>
 * REST 下单委派给 {@link GateTradeExecutor}（独立线程池，避免阻塞 WS 回调线程）。
 *
 * @author Administrator
 */
@Slf4j
public class GateGridTradeService {

    public enum StrategyState {
        WAITING_KLINE, OPENING, ACTIVE, REOPENING_LONG, REOPENING_SHORT, STOPPED
    }

    private final GateConfig config;
    private final GateTradeExecutor executor;
    private final FuturesApi futuresApi;
    private static final String SETTLE = "usdt";

    private volatile StrategyState state = StrategyState.WAITING_KLINE;

    /** 多头是否活跃（有仓位） */
    private volatile boolean longActive = false;
    /** 空头是否活跃（有仓位） */
    private volatile boolean shortActive = false;

    private BigDecimal longEntryPrice;
    private BigDecimal shortEntryPrice;
    private volatile BigDecimal lastKlinePrice;
    private volatile BigDecimal cumulativePnl = BigDecimal.ZERO;
    private Long userId;

    private int longReopenFails = 0;
    private int shortReopenFails = 0;

    public GateGridTradeService(GateConfig config) {
        this.config = config;
        ApiClient apiClient = new ApiClient();
        apiClient.setBasePath(config.getRestBasePath());
        apiClient.setApiKeySecret(config.getApiKey(), config.getApiSecret());
        this.futuresApi = new FuturesApi(apiClient);
        this.executor = new GateTradeExecutor(apiClient, config.getContract());
    }

    public void init() {
        try {
            ApiClient detailClient = new ApiClient();
            detailClient.setBasePath(config.getRestBasePath());
            detailClient.setApiKeySecret(config.getApiKey(), config.getApiSecret());
            AccountDetail detail = new AccountApi(detailClient).getAccountDetail();
            this.userId = detail.getUserId();
            log.info("[Gate] uid:{}", userId);

            FuturesAccount account = futuresApi.listFuturesAccounts(SETTLE);
            if (!config.getPositionMode().equals(account.getPositionMode())) {
                futuresApi.setPositionMode(SETTLE, config.getPositionMode());
            }
            log.info("[Gate] mode:{} balance:{}", config.getPositionMode(), account.getAvailable());

            futuresApi.cancelPriceTriggeredOrderList(SETTLE, config.getContract());
            log.info("[Gate] old orders cleared");

            futuresApi.updateContractPositionLeverageCall(
                    SETTLE, config.getContract(), config.getLeverage(),
                    config.getMarginMode(), config.getPositionMode(), null);
            log.info("[Gate] {}x {}", config.getLeverage(), config.getMarginMode());
        } catch (GateApiException e) {
            log.error("[Gate] init fail, label:{}, msg:{}", e.getErrorLabel(), e.getMessage());
        } catch (ApiException e) {
            log.error("[Gate] init fail, code:{}", e.getCode());
        }
    }

    public void startGrid() {
        if (state != StrategyState.WAITING_KLINE && state != StrategyState.STOPPED) {
            log.warn("[Gate] already running, state:{}", state);
            return;
        }
        state = StrategyState.WAITING_KLINE;
        cumulativePnl = BigDecimal.ZERO;
        longActive = false;
        shortActive = false;
        longReopenFails = 0;
        shortReopenFails = 0;
        log.info("[Gate] grid started");
    }

    public void stopGrid() {
        state = StrategyState.STOPPED;
        executor.cancelAllPriceTriggeredOrders();
        executor.shutdown();
        log.info("[Gate] stopped, pnl:{}", cumulativePnl);
    }

    /**
     * K 线回调。首次价格就绪 → 异步双开。
     */
    public void onKline(BigDecimal closePrice) {
        lastKlinePrice = closePrice;
        if (state != StrategyState.WAITING_KLINE) {
            return;
        }

        state = StrategyState.OPENING;
        log.info("[Gate] first kline, opening...");

        executor.openLong(config.getQuantity(), () -> {
            synchronized (this) {
                longEntryPrice = lastKlinePrice;
                longActive = true;
            }
            executor.placeTakeProfit(longTpPrice(), FuturesPriceTrigger.RuleEnum.NUMBER_1,
                    "close-long-position", "close_long");
        });
        executor.openShort(negate(config.getQuantity()), () -> {
            synchronized (this) {
                shortEntryPrice = lastKlinePrice;
                shortActive = true;
            }
            executor.placeTakeProfit(shortTpPrice(), FuturesPriceTrigger.RuleEnum.NUMBER_2,
                    "close-short-position", "close_short");
            if (longActive && shortActive && state != StrategyState.STOPPED) {
                state = StrategyState.ACTIVE;
                log.info("[Gate] active, long:{}, short:{}, tpL:{}, tpS:{}",
                        longEntryPrice, shortEntryPrice, longTpPrice(), shortTpPrice());
            }
        });
    }

    /**
     * 仓位推送回调。检测 size=0 触发补仓。
     */
    public void onPositionUpdate(String contract, String mode, BigDecimal size, BigDecimal entryPrice) {
        if (state == StrategyState.STOPPED || state == StrategyState.WAITING_KLINE) {
            return;
        }

        boolean hasPosition = size.abs().compareTo(BigDecimal.ZERO) > 0;

        if ("dual_long".equals(mode)) {
            if (longActive && !hasPosition) {
                log.info("[Gate] long closed");
                longActive = false;
                tryReopenLong(0);
            } else if (hasPosition) {
                longActive = true;
                longEntryPrice = entryPrice;
            }
        } else if ("dual_short".equals(mode)) {
            if (shortActive && !hasPosition) {
                log.info("[Gate] short closed");
                shortActive = false;
                tryReopenShort(0);
            } else if (hasPosition) {
                shortActive = true;
                shortEntryPrice = entryPrice;
            }
        }
    }

    /**
     * 平仓推送回调。累加 pnl 并检查停止条件。
     */
    public void onPositionClose(String contract, String side, BigDecimal pnl) {
        if (state == StrategyState.STOPPED) {
            return;
        }
        cumulativePnl = cumulativePnl.add(pnl);
        log.info("[Gate] pnl+{}, side:{}, total:{}", pnl, side, cumulativePnl);

        if (cumulativePnl.compareTo(config.getOverallTp()) >= 0) {
            log.info("[Gate] TP reached {}→STOPPED", cumulativePnl);
            state = StrategyState.STOPPED;
        } else if (cumulativePnl.compareTo(config.getMaxLoss().negate()) <= 0) {
            log.info("[Gate] loss {}→STOPPED", cumulativePnl);
            state = StrategyState.STOPPED;
        }
    }

    // ---- reopen with retry ----

    private void tryReopenLong(int retry) {
        if (state == StrategyState.STOPPED) {
            return;
        }
        if (longActive) {
            return;
        }

        state = StrategyState.REOPENING_LONG;
        executor.openLong(config.getQuantity(), () -> {
            synchronized (this) {
                longEntryPrice = lastKlinePrice;
                longActive = true;
            }
            executor.placeTakeProfit(longTpPrice(), FuturesPriceTrigger.RuleEnum.NUMBER_1,
                    "close-long-position", "close_long");
            longReopenFails = 0;
            if (state != StrategyState.STOPPED) {
                state = StrategyState.ACTIVE;
            }
            log.info("[Gate] long reopened, price:{}", longEntryPrice);
        });
    }

    private void tryReopenShort(int retry) {
        if (state == StrategyState.STOPPED) {
            return;
        }
        if (shortActive) {
            return;
        }

        state = StrategyState.REOPENING_SHORT;
        executor.openShort(negate(config.getQuantity()), () -> {
            synchronized (this) {
                shortEntryPrice = lastKlinePrice;
                shortActive = true;
            }
            executor.placeTakeProfit(shortTpPrice(), FuturesPriceTrigger.RuleEnum.NUMBER_2,
                    "close-short-position", "close_short");
            shortReopenFails = 0;
            if (state != StrategyState.STOPPED) {
                state = StrategyState.ACTIVE;
            }
            log.info("[Gate] short reopened, price:{}", shortEntryPrice);
        });
    }

    // ---- util ----

    private BigDecimal longTpPrice() {
        return lastKlinePrice.multiply(BigDecimal.ONE.add(config.getGridRate()))
                .setScale(1, RoundingMode.HALF_UP);
    }

    private BigDecimal shortTpPrice() {
        return lastKlinePrice.multiply(BigDecimal.ONE.subtract(config.getGridRate()))
                .setScale(1, RoundingMode.HALF_UP);
    }

    private String negate(String qty) {
        return qty.startsWith("-") ? qty.substring(1) : "-" + qty;
    }

    public BigDecimal getLastKlinePrice() { return lastKlinePrice; }
    public boolean isStrategyActive() { return state != StrategyState.STOPPED && state != StrategyState.WAITING_KLINE; }
    public BigDecimal getCumulativePnl() { return cumulativePnl; }
    public Long getUserId() { return userId; }
    public StrategyState getState() { return state; }
}