Yi.Admin/Yi.Abp.Net8/module/ai-hub/Yi.Framework.AiHub.Domain/AiChat/Impl/AzureRestChatService.cs

using System.Runtime.CompilerServices;
using System.Text;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;
using OpenAI.Chat;
using Yi.Framework.AiHub.Domain.Extensions;
using Yi.Framework.AiHub.Domain.Shared.Dtos;

namespace Yi.Framework.AiHub.Domain.AiChat.Impl;

public class AzureRestChatService : IChatService
{
    public AzureRestChatService()
    {
    }

    public async IAsyncEnumerable<string> CompleteChatAsync(AiModelDescribe aiModelDescribe, List<ChatMessage> messages,
        [EnumeratorCancellation] CancellationToken cancellationToken)
    {
        // 设置API URL
        var apiUrl = $"{aiModelDescribe.Endpoint}models/chat/completions";
        // 准备请求内容
        var requestBody = new
        {
            messages = messages.Select(x => new
            {
                role = x.GetRoleAsString(),
                content = x.Content.FirstOrDefault()?.Text
            }).ToList(),
            stream = true,
            max_tokens = 2048,
            temperature = 0.8,
            top_p = 0.1,
            presence_penalty = 0,
            frequency_penalty = 0,
            model = aiModelDescribe.ModelId
        };

        // 序列化请求内容为JSON
        string jsonBody = JsonConvert.SerializeObject(requestBody);

        using var httpClient = new HttpClient();
        // 设置请求头
        httpClient.DefaultRequestHeaders.Add("Authorization", $"Bearer {aiModelDescribe.ApiKey}");
        // 其他头信息如Content-Type在StringContent中设置

        // 构造 POST 请求
        var request = new HttpRequestMessage(HttpMethod.Post, apiUrl);

        // 设置请求内容（示例）
        request.Content = new StringContent(jsonBody, Encoding.UTF8, "application/json");

        // 发送POST请求
        HttpResponseMessage response =
            await httpClient.SendAsync(request, HttpCompletionOption.ResponseHeadersRead, cancellationToken);
        // 确认响应成功
        response.EnsureSuccessStatusCode();

        // 读取响应内容
        var responseStream = await response.Content.ReadAsStreamAsync(cancellationToken);
        // 从流中读取数据并输出到控制台
        using var streamReader = new StreamReader(responseStream);
        string line;
        while ((line = await streamReader.ReadLineAsync(cancellationToken)) != null)
        {
            var result = GetContent(line);
            if (result is not null)
            {
                yield return result;
            }
        }
    }

    private string? GetContent(string line)
    {
        if (string.IsNullOrWhiteSpace(line))
            return null;
        string prefix = "data: ";
        line = line.Substring(prefix.Length);


        try
        {
            // 解析为JObject
            var jsonObj = JObject.Parse(line);
            var content = jsonObj["choices"][0]["delta"]["content"].ToString();
            return content;
            // // 判断choices是否存在且是数组，并且有元素
            // if (jsonObj.TryGetValue("choices", out var choicesToken) && choicesToken is JArray choicesArray &&
            //     choicesArray.Count > 0)
            // {
            //     var firstChoice = choicesArray[0] as JObject;
            //     // 判断delta字段是否存在
            //     if (firstChoice.TryGetValue("delta", out var deltaToken))
            //     {
            //         // 获取content字段
            //         if (deltaToken.Type == JTokenType.Object && ((JObject)deltaToken).TryGetValue("content", out var contentToken))
            //         {
            //             return contentToken.ToString();
            //         }
            //     }
            // }
        }
        catch (Exception)
        {
            // 解析失败
            return null;
        }
    }
}