package com.smartor.common;

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.json.JsonMapper;
import lombok.extern.slf4j.Slf4j;
import okhttp3.*;

import javax.net.ssl.*;
import java.io.IOException;
import java.net.URI;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
import java.security.SecureRandom;
import java.security.cert.X509Certificate;
import java.util.*;
import java.util.concurrent.locks.ReentrantLock;

@Slf4j
public class LyraTokenUtil {

    private static final List<LyraTokenUtil> cache = new ArrayList<>();
    private static final JsonMapper objectMapper = JsonMapper.builder().build();
    private final OkHttpClient client;
    private final URI url;
    private final String clientId;
    private final String clientSecret;
    private final ReentrantLock lock = new ReentrantLock();
    private Date expireTime;
    private String token;
    private final X509TrustManager trustManager;

    private LyraTokenUtil(URI url, String clientId, String clientSecret) {
        this.url = url;
        this.clientId = clientId;
        this.clientSecret = clientSecret;

        SSLContext sslContext;
        try {
            // 创建一个信任所有证书的 TrustManager
            TrustManager[] trustAllManagers = new TrustManager[]{new X509TrustManager() {
                @Override
                public void checkClientTrusted(X509Certificate[] chain, String authType) {
                }

                @Override
                public void checkServerTrusted(X509Certificate[] chain, String authType) {
                }

                @Override
                public X509Certificate[] getAcceptedIssuers() {
                    return new X509Certificate[0];
                }
            }};

            // 保存 TrustManager
            this.trustManager = (X509TrustManager) trustAllManagers[0];

            // 初始化 SSLContext
            sslContext = SSLContext.getInstance("TLS");
            sslContext.init(null, trustAllManagers, new SecureRandom());
        } catch (Exception e) {
            throw new IllegalStateException("Failed to initialize SSLContext", e);
        }

        // 创建 OkHttpClient，设置自定义的 SSLContext
        this.client = new OkHttpClient.Builder().sslSocketFactory(sslContext.getSocketFactory(), trustManager) // 直接使用保存的 TrustManager
                .hostnameVerifier((hostname, session) -> true) // 忽略主机名验证
                .build();
    }

    public static synchronized LyraTokenUtil createLyraTokenUtil(String url, String clientId, String clientSecret) {
        return cache.stream().filter(it -> it.url.equals(URI.create(url))).findFirst().orElseGet(() -> {
            LyraTokenUtil lyraTokenUtil = new LyraTokenUtil(URI.create(url), clientId, clientSecret);
            cache.add(lyraTokenUtil);
            return lyraTokenUtil;
        });
    }

    public String getToken() throws IOException {
        lock.lock();
        try {
            if (expireTime == null || expireTime.before(new Date())) {
                RequestBody formBody = new FormBody.Builder().add("grant_type", "client_credentials").add("client_id", clientId).add("client_secret", URLEncoder.encode(clientSecret, StandardCharsets.UTF_8.toString())).build();

                Request request = new Request.Builder().url(url.toURL()).post(formBody).build();

                try (Response response = client.newCall(request).execute()) {
                    if (response.isSuccessful()) {
                        ResponseBody body = response.body();
                        if (body != null) {
                            JsonNode jsonNode = objectMapper.readTree(body.string());
                            String accessToken = jsonNode.get("access_token").asText();
                            String tokenType = jsonNode.get("token_type").asText();
                            this.token = tokenType + " " + accessToken;
                            int expiresIn = jsonNode.get("expires_in").asInt();
                            this.expireTime = new Date(System.currentTimeMillis() + (expiresIn - 300) * 1000);
                        } else {
                            throw new RuntimeException("Response body is null");
                        }
                    } else {
                        throw new RuntimeException("Failed to get token, HTTP status: " + response.code());
                    }
                }
            }
            return token;
        } finally {
            lock.unlock();
        }
    }
}