content: /*
   *  Copyright (c) 2023-2025, Agents-Flex (fuhai999@gmail.com).
   *  <p>
   *  Licensed under the Apache License, Version 2.0 (the "License");
   *  you may not use this file except in compliance with the License.
   *  You may obtain a copy of the License at
   *  <p>
   *  http://www.apache.org/licenses/LICENSE-2.0
   *  <p>
   *  Unless required by applicable law or agreed to in writing, software
   *  distributed under the License is distributed on an "AS IS" BASIS,
   *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   *  See the License for the specific language governing permissions and
   *  limitations under the License.
   */
  package com.agentsflex.llm.tencent;
  
  import com.agentsflex.core.llm.ChatOptions;
  import com.agentsflex.core.message.*;
  import com.agentsflex.core.parser.AiMessageParser;
  import com.agentsflex.core.parser.impl.DefaultAiMessageParser;
  import com.agentsflex.core.prompt.DefaultPromptFormat;
  import com.agentsflex.core.prompt.ImagePrompt;
  import com.agentsflex.core.prompt.Prompt;
  import com.agentsflex.core.prompt.PromptFormat;
  import com.agentsflex.core.util.Maps;
  import com.agentsflex.core.util.MessageUtil;
  import com.agentsflex.core.util.StringUtil;
  import com.alibaba.fastjson.JSONPath;
  import com.tencentcloudapi.common.DatatypeConverter;
  
  import javax.crypto.Mac;
  import javax.crypto.spec.SecretKeySpec;
  import java.nio.charset.Charset;
  import java.nio.charset.StandardCharsets;
  import java.security.MessageDigest;
  import java.text.SimpleDateFormat;
  import java.util.*;
  
  public class TencentLlmUtil {
  
      private static final PromptFormat promptFormat = new DefaultPromptFormat() {
          @Override
          protected void buildMessageContent(Message message, Map<String, Object> map) {
              map.clear();
              if (message instanceof HumanMessage) {
                  map.put("Role", "user");
              } else if (message instanceof AiMessage) {
                  map.put("Role", "assistant");
                  map.put("Content", "");
                  AiMessage aiMessage = (AiMessage) message;
                  List<FunctionCall> calls = aiMessage.getCalls();
                  if (calls != null && !calls.isEmpty()) {
                      buildToolCalls(map, calls);
                      return;
                  }
              } else if (message instanceof SystemMessage) {
                  map.put("Role", "system");
              } else if (message instanceof ToolMessage) {
                  map.put("Role", "tool");
                  map.put("Tool_call_id", ((ToolMessage) message).getToolCallId());
              }
              if (message instanceof HumanImageMessage) {
                  ImagePrompt prompt = ((HumanImageMessage) message).getPrompt();
                  List<Map<String, Object>> list = new ArrayList<>();
                  List<String> imageUrls = prompt.getImageUrls();
                  if (imageUrls != null) {
                      for (String imageUrl : imageUrls) {
                          list.add(Maps.of("Type", "image_url").set("Text", prompt.getContent()).set("ImageUrl", Maps.of("Url", imageUrl)));
                      }
                  }
  
                  map.put("Contents", list);
              } else {
                  map.put("Content", message.getMessageContent());
              }
          }
  
          @Override
          protected Object buildToolCallsArguments(Map<String, Object> arguments) {
              return arguments;
          }
      };
  
      private final static Charset UTF8 = StandardCharsets.UTF_8;
      private final static String CT_JSON = "application/json; charset=utf-8";
  
      public static byte[] hmac256(byte[] key, String msg) throws Exception {
          Mac mac = Mac.getInstance("HmacSHA256");
          SecretKeySpec secretKeySpec = new SecretKeySpec(key, mac.getAlgorithm());
          mac.init(secretKeySpec);
          return mac.doFinal(msg.getBytes(UTF8));
      }
  
      public static String sha256Hex(String s) throws Exception {
          MessageDigest md = MessageDigest.getInstance("SHA-256");
          byte[] d = md.digest(s.getBytes(UTF8));
          return DatatypeConverter.printHexBinary(d).toLowerCase();
      }
  
      public static Map<String, String> createAuthorizationToken(TencentLlmConfig config, String action, String payload) {
          try {
              String service = config.getService();
              String host = config.getHost();
              String version = "2023-09-01";
              String algorithm = "TC3-HMAC-SHA256";
              String timestamp = String.valueOf(System.currentTimeMillis() / 1000);
              SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
              // 注意时区，否则容易出错
              sdf.setTimeZone(TimeZone.getTimeZone("UTC"));
              String date = sdf.format(new Date(Long.parseLong(timestamp + "000")));
  
              // ************* 步骤 1：拼接规范请求串 *************
              String httpRequestMethod = "POST";
              String canonicalUri = "/";
              String canonicalQueryString = "";
              String canonicalHeaders = "content-type:application/json; charset=utf-8\n"
                  + "host:" + host + "\n" + "x-tc-action:" + action.toLowerCase() + "\n";
              String signedHeaders = "content-type;host;x-tc-action";
  
              String hashedRequestPayload = sha256Hex(payload);
              String canonicalRequest = httpRequestMethod + "\n" + canonicalUri + "\n" + canonicalQueryString + "\n"
                  + canonicalHeaders + "\n" + signedHeaders + "\n" + hashedRequestPayload;
              System.out.println(canonicalRequest);
  
              // ************* 步骤 2：拼接待签名字符串 *************
              String credentialScope = date + "/" + service + "/" + "tc3_request";
              String hashedCanonicalRequest = sha256Hex(canonicalRequest);
              String stringToSign = algorithm + "\n" + timestamp + "\n" + credentialScope + "\n" + hashedCanonicalRequest;
              System.out.println(stringToSign);
  
              // ************* 步骤 3：计算签名 *************
              byte[] secretDate = hmac256(("TC3" + config.getApiKey()).getBytes(UTF8), date);
              byte[] secretService = hmac256(secretDate, service);
              byte[] secretSigning = hmac256(secretService, "tc3_request");
              String signature = DatatypeConverter.printHexBinary(hmac256(secretSigning, stringToSign)).toLowerCase();
              System.out.println(signature);
  
              // ************* 步骤 4：拼接 Authorization *************
              String authorization = algorithm + " " + "Credential=" + config.getApiSecret() + "/" + credentialScope + ", "
                  + "SignedHeaders=" + signedHeaders + ", " + "Signature=" + signature;
              System.out.println(authorization);
  
              Map<String, String> headers = new HashMap<>();
              headers.put("Authorization", authorization);
              headers.put("Content-Type", CT_JSON);
              headers.put("Host", host);
              headers.put("X-TC-Action", action);
              headers.put("X-TC-Timestamp", timestamp);
              headers.put("X-TC-Version", version);
              return headers;
          } catch (Exception e) {
              throw new RuntimeException(e);
          }
      }
  
      public static AiMessageParser getAiMessageParser(boolean isStream) {
          DefaultAiMessageParser aiMessageParser = new DefaultAiMessageParser();
          String data;
          if (isStream) {
              data = "";
          } else {
              data = "Response.";
          }
          aiMessageParser.setIndexPath("$." + data + "choices[0].Index");
          if (isStream) {
              aiMessageParser.setContentPath("$." + data + "Choices[0].Delta.Content");
          } else {
              aiMessageParser.setContentPath("$." + data + "Choices[0].Message.Content");
          }
          aiMessageParser.setTotalTokensPath("$." + data + "Usage.TotalTokens");
          aiMessageParser.setCompletionTokensPath("$." + data + "Usage.CompletionTokens");
          aiMessageParser.setPromptTokensPath("$." + data + "Usage.PromptTokens");
          aiMessageParser.setStatusParser(content -> {
              String done = (String) JSONPath.eval(content, "$." + data + "Choices[0].FinishReason");
              if (StringUtil.hasText(done)) {
                  return MessageStatus.END;
              }
              return MessageStatus.MIDDLE;
          });
          return aiMessageParser;
      }
  
  
      public static String promptToPayload(Prompt prompt, TencentLlmConfig config, boolean withStream, ChatOptions options) {
          List<Message> messages = prompt.toMessages();
          HumanMessage message = MessageUtil.findLastHumanMessage(messages);
          return Maps.of("Model", Optional.ofNullable(options.getModel()).orElse(config.getModel()))
              .set("Messages", promptFormat.toMessagesJsonObject(messages))
              .setIf(withStream, "Stream", withStream)
              .setIfNotEmpty("Tools", promptFormat.toFunctionsJsonObject(message))
              .setIfContainsKey("Tools", "ToolChoice", MessageUtil.getToolChoice(message))
              .setIfNotNull("top_p", options.getTopP())
              .setIfNotEmpty("Stop", options.getStop())
              .setIf(map -> !map.containsKey("tools") && options.getMaxTokens() != null, "max_tokens", options.getMaxTokens())
              .setIfNotEmpty(options.getExtra())
              .toJSON();
      }
  
  
  }
  