package com.wb.domainserver.security.config;

import com.github.benmanes.caffeine.cache.CacheLoader;
import com.github.benmanes.caffeine.cache.Caffeine;
import com.wb.domainserver.realm.RealmResolver;
import org.springframework.cache.annotation.EnableCaching;
import org.springframework.cache.caffeine.CaffeineCacheManager;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import java.util.concurrent.CompletableFuture;
import java.util.concurrent.Executor;
import java.util.concurrent.TimeUnit;

@Configuration
@EnableCaching
public class CacheConfig {

    private final ApplicationContext applicationContext;

    public CacheConfig(ApplicationContext applicationContext) {
        this.applicationContext = applicationContext;
    }

    @Bean
    public CaffeineCacheManager cacheManager() {
        CaffeineCacheManager cacheManager = new CaffeineCacheManager();
        cacheManager.setCaffeine(caffeineCacheBuilder());
        cacheManager.setCacheLoader(cacheLoader());
        return cacheManager;
    }

    @Bean
    public Caffeine<Object, Object> caffeineCacheBuilder() {
        return Caffeine.newBuilder()
                .expireAfterWrite(10, TimeUnit.MINUTES)
                .maximumSize(100);
    }

    @Bean
    public CacheLoader<Object, Object> cacheLoader() {
        return new CacheLoader<>() {
            @Override
            public Object load(Object key) {
                return loadAsync(key).join();
            }

            @Override
            public CompletableFuture<Object> asyncReload(Object key, Object oldValue, Executor executor) {
                return loadAsync(key);
            }

            private CompletableFuture<Object> loadAsync(Object key) {
                String hostUrl = (String) key;
                RealmResolver realmResolver = applicationContext.getBean(RealmResolver.class);
                return realmResolver.resolveRealmInternalDirect(hostUrl);
            }
        };
    }
}