| 1 | using System.Net.Http.Json; |
| 2 | using System.Text.Json; |
| 3 | using System.Runtime.CompilerServices; |
| 4 | |
| 5 | namespace CascadeIDE.Services; |
| 6 | |
| 7 | /// <summary>Провайдер чата через Anthropic API (Claude).</summary> |
| 8 | public sealed class AnthropicProvider : IAiChatProvider |
| 9 | { |
| 10 | private const string DefaultBaseUrl = "https://api.anthropic.com"; |
| 11 | private readonly HttpClient _httpClient; |
| 12 | private readonly string _apiKey; |
| 13 | private readonly string _modelId; |
| 14 | |
| 15 | public AnthropicProvider(string apiKey, string modelId, string? baseUrl = null) |
| 16 | { |
| 17 | _apiKey = apiKey ?? ""; |
| 18 | _modelId = modelId ?? "claude-sonnet-4-20250514"; |
| 19 | var baseUri = new Uri(baseUrl ?? DefaultBaseUrl); |
| 20 | _httpClient = new HttpClient { BaseAddress = baseUri }; |
| 21 | _httpClient.DefaultRequestHeaders.Add("x-api-key", _apiKey); |
| 22 | _httpClient.DefaultRequestHeaders.Add("anthropic-version", "2023-06-01"); |
| 23 | } |
| 24 | |
| 25 | public async IAsyncEnumerable<string> StreamChatAsync( |
| 26 | string model, |
| 27 | IReadOnlyList<ChatMessage> messages, |
| 28 | [EnumeratorCancellation] CancellationToken cancellationToken = default, |
| 29 | ChatTurnUsageCollector? usageCollector = null) |
| 30 | { |
| 31 | var modelId = string.IsNullOrEmpty(model) ? _modelId : model; |
| 32 | if (string.IsNullOrEmpty(_apiKey)) |
| 33 | { |
| 34 | yield return "[Error: Anthropic API key not set.]"; |
| 35 | yield break; |
| 36 | } |
| 37 | |
| 38 | var requestBody = new |
| 39 | { |
| 40 | model = modelId, |
| 41 | max_tokens = 8192, |
| 42 | stream = true, |
| 43 | messages = messages.Select(m => new { role = m.Role == "assistant" ? "assistant" : "user", content = m.Content }).ToArray() |
| 44 | }; |
| 45 | |
| 46 | using var request = new HttpRequestMessage(HttpMethod.Post, "v1/messages"); |
| 47 | request.Content = JsonContent.Create(requestBody); |
| 48 | |
| 49 | using var response = await _httpClient.SendAsync(request, HttpCompletionOption.ResponseHeadersRead, cancellationToken); |
| 50 | if (!response.IsSuccessStatusCode) |
| 51 | { |
| 52 | var err = await response.Content.ReadAsStringAsync(cancellationToken); |
| 53 | yield return $"[Anthropic error {(int)response.StatusCode}: {err}]"; |
| 54 | yield break; |
| 55 | } |
| 56 | |
| 57 | await using var stream = await response.Content.ReadAsStreamAsync(cancellationToken); |
| 58 | using var reader = new StreamReader(stream); |
| 59 | while (await reader.ReadLineAsync(cancellationToken) is { } line) |
| 60 | { |
| 61 | if (!line.StartsWith("data:", StringComparison.Ordinal)) continue; |
| 62 | var json = line.Length > 5 ? line[5..].Trim() : ""; |
| 63 | if (json == "[DONE]" || string.IsNullOrEmpty(json)) continue; |
| 64 | string? text = null; |
| 65 | try |
| 66 | { |
| 67 | using var doc = JsonDocument.Parse(json); |
| 68 | var root = doc.RootElement; |
| 69 | if (root.TryGetProperty("type", out var typeEl) && typeEl.GetString() == "content_block_delta" |
| 70 | && root.TryGetProperty("delta", out var deltaEl) |
| 71 | && deltaEl.TryGetProperty("type", out var deltaType) && deltaType.GetString() == "text_delta" |
| 72 | && deltaEl.TryGetProperty("text", out var textEl)) |
| 73 | text = textEl.GetString(); |
| 74 | } |
| 75 | catch |
| 76 | { |
| 77 | // skip invalid line |
| 78 | } |
| 79 | if (!string.IsNullOrEmpty(text)) |
| 80 | yield return text; |
| 81 | } |
| 82 | } |
| 83 | } |
| 84 | |