import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.zhiwonders.paperserver.service.IAuthService;
import lombok.extern.slf4j.Slf4j;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.http.MediaType;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.servlet.mvc.method.annotation.SseEmitter;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.nio.charset.StandardCharsets;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;


@RestController
@RequestMapping("/api/v1")
@Slf4j
public class OpenAIController {

    @Value("${ai.config.deepseek.apiKey}")
    private String API_KEY;

    @Value("${ai.config.deepseek.baseUrl}")
    private String API_URL;

    @Autowired
    private IAuthService authService;

    private final ExecutorService executorService = Executors.newCachedThreadPool();
    private final ObjectMapper objectMapper = new ObjectMapper();

    @PostMapping(value = "/chat", produces = MediaType.TEXT_EVENT_STREAM_VALUE)
    public SseEmitter chat(
//            @RequestHeader("Authorization")String token,
                           @RequestBody String question) {
//        String openid = authService.openid(token);
//        if (openid == null) {
//            throw new RuntimeException("用戶未登錄");
//        }
        SseEmitter emitter = new SseEmitter(-1L);
        executorService.execute(() -> {
            try {
                log.info("流式回答開始,問題:{}", question);
                try (CloseableHttpClient client = HttpClients.createDefault()) {
                    HttpPost request = new HttpPost(API_URL);
                    request.setHeader("Content-Type", "application/json");
                    request.setHeader("Authorization", "Bearer " + API_KEY);

                    Map<String, Object> message = new HashMap<>();
                    message.put("role", "user");
                    message.put("content", question);

                    Map<String, Object> requestMap = new HashMap<>();
                    requestMap.put("model", "deepseek-chat");
                    requestMap.put("messages", Collections.singletonList(message));
                    requestMap.put("stream", true);

                    String requestBody = objectMapper.writeValueAsString(requestMap);
                    request.setEntity(new StringEntity(requestBody, StandardCharsets.UTF_8));

                    try (CloseableHttpResponse response = client.execute(request);
                         BufferedReader reader = new BufferedReader(
                                 new InputStreamReader(response.getEntity().getContent(), StandardCharsets.UTF_8))) {
                        String line;
                        while ((line = reader.readLine()) != null) {
                            if (line.startsWith("data: ")) {
                                String jsonData = line.substring(6);
                                if ("[DONE]".equals(jsonData)) {
                                    break;
                                }
                                JsonNode node = objectMapper.readTree(jsonData);
                                String content = node.path("choices")
                                        .path(0)
                                        .path("delta")
                                        .path("content")
                                        .asText("");
                                if (!content.isEmpty()) {
                                    emitter.send(content);
                                }
                            }
                        }
                        log.info("流式回答結(jié)束,{}",question);
                        emitter.complete();
                    }
                } catch (Exception e) {
                    log.error("處理 Deepseek 請(qǐng)求時(shí)發(fā)生錯(cuò)誤", e);
                    emitter.completeWithError(e);
                }
            } catch (Exception e) {
                log.error("處理 Deepseek 請(qǐng)求時(shí)發(fā)生錯(cuò)誤", e);
                emitter.completeWithError(e);
            }
        });
        return emitter;
    }
}

curl -v -X POST \
    http://localhost:8091/api/v1/chat \
    -H "Content-Type: application/json" \
    -d '"幫我寫一篇2000字的 我的祖國的文字"' \
    --no-buffer