GuardSystem

Guard system that validates whether a new order can be placed. Guards are checked in sequence: 1. Position Check - Must be flat 2. Active Orders Check - No orders pending 3. Cooldown Check - Cooldown period must have passed All guards must pass for an order to be allowed.

GuardSystem.java

package com.bookmap.ordermanagement.core;

import com.bookmap.ordermanagement.model.GuardResult;
import velox.api.layer1.common.Log;

import java.time.Duration;

/**
 * Guard system that validates whether a new order can be placed.
 *
 * Guards are checked in sequence:
 * 1. Position Check - Must be flat
 * 2. Active Orders Check - No orders pending
 * 3. Cooldown Check - Cooldown period must have passed
 *
 * All guards must pass for an order to be allowed.
 */
public class GuardSystem {

    // Configuration
    private final String logPrefix;
    private final boolean loggingEnabled;
    private long cooldownMs;

    // Cooldown state
    private volatile long cooldownEndTime;
    private volatile long lastTradeCloseTime;

    /**
     * Creates a new guard system.
     *
     * @param logPrefix Prefix for log messages
     * @param loggingEnabled Whether to enable detailed logging
     * @param cooldownDuration Cooldown period after trade closes
     */
    public GuardSystem(String logPrefix, boolean loggingEnabled, Duration cooldownDuration) {
        this.logPrefix = logPrefix;
        this.loggingEnabled = loggingEnabled;
        this.cooldownMs = cooldownDuration.toMillis();
        this.cooldownEndTime = 0;
        this.lastTradeCloseTime = 0;
    }

    // =========================================================================
    // Main Guard Check
    // =========================================================================

    /**
     * Checks all guards to determine if an order can be placed.
     *
     * @param positionTracker The position tracker
     * @param orderRegistry The order registry
     * @return GuardResult indicating if order is allowed
     */
    public GuardResult canPlaceOrder(PositionTracker positionTracker, OrderRegistry orderRegistry) {

        // Guard 1: Position Check
        if (!positionTracker.isFlat()) {
            GuardResult result = GuardResult.block("PositionGuard",
                String.format("Already in position: %s",
                    positionTracker.isLong() ? "LONG" : "SHORT"));
            logGuardResult(result);
            return result;
        }

        // Guard 2: Active Orders Check
        if (orderRegistry.hasActiveOrders()) {
            GuardResult result = GuardResult.block("ActiveOrdersGuard",
                String.format("Active orders pending: %d", orderRegistry.getActiveOrderCount()));
            logGuardResult(result);
            return result;
        }

        // Guard 3: Cooldown Check
        if (isCooldownActive()) {
            long remainingMs = getCooldownRemaining();
            GuardResult result = GuardResult.block("CooldownGuard",
                String.format("Cooldown active: %d seconds remaining", remainingMs / 1000));
            logGuardResult(result);
            return result;
        }

        // All guards passed
        GuardResult result = GuardResult.allow();
        if (loggingEnabled) {
            Log.info(String.format("%s Guard check: ALLOWED", logPrefix));
        }
        return result;
    }

    /**
     * Logs a guard result if logging is enabled.
     */
    private void logGuardResult(GuardResult result) {
        if (loggingEnabled && result.isBlocked()) {
            Log.info(String.format("%s Guard check: %s", logPrefix, result.toLogMessage()));
        }
    }

    // =========================================================================
    // Cooldown Management
    // =========================================================================

    /**
     * Starts the cooldown timer.
     * Called when a trade closes.
     */
    public void startCooldown() {
        this.lastTradeCloseTime = System.currentTimeMillis();
        this.cooldownEndTime = this.lastTradeCloseTime + cooldownMs;

        if (loggingEnabled) {
            Log.info(String.format("%s Cooldown started: %d seconds",
                logPrefix, cooldownMs / 1000));
        }
    }

    /**
     * Returns true if cooldown is currently active.
     */
    public boolean isCooldownActive() {
        if (cooldownMs <= 0) return false;
        return System.currentTimeMillis() < cooldownEndTime;
    }

    /**
     * Returns the remaining cooldown time in milliseconds.
     */
    public long getCooldownRemaining() {
        if (!isCooldownActive()) return 0;
        return cooldownEndTime - System.currentTimeMillis();
    }

    /**
     * Returns the remaining cooldown time in seconds.
     */
    public int getCooldownRemainingSeconds() {
        return (int) (getCooldownRemaining() / 1000);
    }

    /**
     * Clears the cooldown timer.
     */
    public void clearCooldown() {
        cooldownEndTime = 0;
        if (loggingEnabled) {
            Log.info(String.format("%s Cooldown cleared", logPrefix));
        }
    }

    // =========================================================================
    // Configuration
    // =========================================================================

    /**
     * Sets the cooldown duration.
     *
     * @param duration The cooldown duration
     */
    public void setCooldownDuration(Duration duration) {
        this.cooldownMs = duration.toMillis();
    }

    /**
     * Gets the cooldown duration in milliseconds.
     */
    public long getCooldownMs() {
        return cooldownMs;
    }

    /**
     * Gets the last trade close time.
     */
    public long getLastTradeCloseTime() {
        return lastTradeCloseTime;
    }

    // =========================================================================
    // Reset
    // =========================================================================

    /**
     * Resets all guard state.
     */
    public void reset() {
        cooldownEndTime = 0;
        lastTradeCloseTime = 0;

        if (loggingEnabled) {
            Log.info(String.format("%s Guard system reset", logPrefix));
        }
    }

    // =========================================================================
    // Status
    // =========================================================================

    /**
     * Returns a status summary.
     */
    public String getStatusSummary() {
        if (isCooldownActive()) {
            return String.format("Cooldown: %d seconds remaining", getCooldownRemainingSeconds());
        }
        return "Ready";
    }

    @Override
    public String toString() {
        return getStatusSummary();
    }
}