package com.ruoyi.ai.context;

import com.ruoyi.framework.security.LoginUser;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;

import java.time.Duration;
import java.time.Instant;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;

@Component
public class AiSessionUserContext {

    private final Map<String, LoginUser> loginUserByMemoryId = new ConcurrentHashMap<>();
    private final Map<String, Instant> lastAccessTimeByMemoryId = new ConcurrentHashMap<>();
    private static final Duration SESSION_TIMEOUT = Duration.ofHours(24);

    public void bind(String memoryId, LoginUser loginUser) {
        if (!StringUtils.hasText(memoryId) || loginUser == null) {
            return;
        }
        loginUserByMemoryId.put(memoryId, loginUser);
        lastAccessTimeByMemoryId.put(memoryId, Instant.now());
    }

    public LoginUser get(String memoryId) {
        if (!StringUtils.hasText(memoryId)) {
            return null;
        }
        if (isExpired(memoryId)) {
            remove(memoryId);
            return null;
        }
        lastAccessTimeByMemoryId.put(memoryId, Instant.now());
        return loginUserByMemoryId.get(memoryId);
    }

    public void remove(String memoryId) {
        if (!StringUtils.hasText(memoryId)) {
            return;
        }
        loginUserByMemoryId.remove(memoryId);
        lastAccessTimeByMemoryId.remove(memoryId);
    }

    public void cleanExpiredSessions() {
        Instant now = Instant.now();
        lastAccessTimeByMemoryId.entrySet().removeIf(entry -> {
            boolean expired = Duration.between(entry.getValue(), now).compareTo(SESSION_TIMEOUT) > 0;
            if (expired) {
                loginUserByMemoryId.remove(entry.getKey());
            }
            return expired;
        });
    }

    private boolean isExpired(String memoryId) {
        Instant lastAccess = lastAccessTimeByMemoryId.get(memoryId);
        if (lastAccess == null) {
            return true;
        }
        return Duration.between(lastAccess, Instant.now()).compareTo(SESSION_TIMEOUT) > 0;
    }
}