copilot_chat.rs

  1use std::path::PathBuf;
  2use std::sync::Arc;
  3use std::sync::OnceLock;
  4
  5use anyhow::{anyhow, Result};
  6use chrono::DateTime;
  7use fs::Fs;
  8use futures::{io::BufReader, stream::BoxStream, AsyncBufReadExt, AsyncReadExt, StreamExt};
  9use gpui::{AppContext, AsyncAppContext, Global};
 10use http_client::{AsyncBody, HttpClient, Method, Request as HttpRequest};
 11use paths::home_dir;
 12use serde::{Deserialize, Serialize};
 13use settings::watch_config_file;
 14use strum::EnumIter;
 15use ui::Context;
 16
 17pub const COPILOT_CHAT_COMPLETION_URL: &str = "https://api.githubcopilot.com/chat/completions";
 18pub const COPILOT_CHAT_AUTH_URL: &str = "https://api.github.com/copilot_internal/v2/token";
 19
 20#[derive(Clone, Copy, Serialize, Deserialize, Debug, Eq, PartialEq)]
 21#[serde(rename_all = "lowercase")]
 22pub enum Role {
 23    User,
 24    Assistant,
 25    System,
 26}
 27
 28#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
 29#[derive(Clone, Debug, Default, Serialize, Deserialize, PartialEq, EnumIter)]
 30pub enum Model {
 31    #[default]
 32    #[serde(alias = "gpt-4o", rename = "gpt-4o-2024-05-13")]
 33    Gpt4o,
 34    #[serde(alias = "gpt-4", rename = "gpt-4")]
 35    Gpt4,
 36    #[serde(alias = "gpt-3.5-turbo", rename = "gpt-3.5-turbo")]
 37    Gpt3_5Turbo,
 38    #[serde(alias = "o1-preview", rename = "o1-preview-2024-09-12")]
 39    O1Preview,
 40    #[serde(alias = "o1-mini", rename = "o1-mini-2024-09-12")]
 41    O1Mini,
 42    #[serde(alias = "claude-3-5-sonnet", rename = "claude-3.5-sonnet")]
 43    Claude3_5Sonnet,
 44}
 45
 46impl Model {
 47    pub fn uses_streaming(&self) -> bool {
 48        match self {
 49            Self::Gpt4o | Self::Gpt4 | Self::Gpt3_5Turbo | Self::Claude3_5Sonnet => true,
 50            Self::O1Mini | Self::O1Preview => false,
 51        }
 52    }
 53
 54    pub fn from_id(id: &str) -> Result<Self> {
 55        match id {
 56            "gpt-4o" => Ok(Self::Gpt4o),
 57            "gpt-4" => Ok(Self::Gpt4),
 58            "gpt-3.5-turbo" => Ok(Self::Gpt3_5Turbo),
 59            "o1-preview" => Ok(Self::O1Preview),
 60            "o1-mini" => Ok(Self::O1Mini),
 61            "claude-3-5-sonnet" => Ok(Self::Claude3_5Sonnet),
 62            _ => Err(anyhow!("Invalid model id: {}", id)),
 63        }
 64    }
 65
 66    pub fn id(&self) -> &'static str {
 67        match self {
 68            Self::Gpt3_5Turbo => "gpt-3.5-turbo",
 69            Self::Gpt4 => "gpt-4",
 70            Self::Gpt4o => "gpt-4o",
 71            Self::O1Mini => "o1-mini",
 72            Self::O1Preview => "o1-preview",
 73            Self::Claude3_5Sonnet => "claude-3-5-sonnet",
 74        }
 75    }
 76
 77    pub fn display_name(&self) -> &'static str {
 78        match self {
 79            Self::Gpt3_5Turbo => "GPT-3.5",
 80            Self::Gpt4 => "GPT-4",
 81            Self::Gpt4o => "GPT-4o",
 82            Self::O1Mini => "o1-mini",
 83            Self::O1Preview => "o1-preview",
 84            Self::Claude3_5Sonnet => "Claude 3.5 Sonnet",
 85        }
 86    }
 87
 88    pub fn max_token_count(&self) -> usize {
 89        match self {
 90            Self::Gpt4o => 64000,
 91            Self::Gpt4 => 32768,
 92            Self::Gpt3_5Turbo => 12288,
 93            Self::O1Mini => 20000,
 94            Self::O1Preview => 20000,
 95            Self::Claude3_5Sonnet => 200_000,
 96        }
 97    }
 98}
 99
100#[derive(Serialize, Deserialize)]
101pub struct Request {
102    pub intent: bool,
103    pub n: usize,
104    pub stream: bool,
105    pub temperature: f32,
106    pub model: Model,
107    pub messages: Vec<ChatMessage>,
108}
109
110impl Request {
111    pub fn new(model: Model, messages: Vec<ChatMessage>) -> Self {
112        Self {
113            intent: true,
114            n: 1,
115            stream: model.uses_streaming(),
116            temperature: 0.1,
117            model,
118            messages,
119        }
120    }
121}
122
123#[derive(Serialize, Deserialize, Debug, Eq, PartialEq)]
124pub struct ChatMessage {
125    pub role: Role,
126    pub content: String,
127}
128
129#[derive(Deserialize, Debug)]
130#[serde(tag = "type", rename_all = "snake_case")]
131pub struct ResponseEvent {
132    pub choices: Vec<ResponseChoice>,
133    pub created: u64,
134    pub id: String,
135}
136
137#[derive(Debug, Deserialize)]
138pub struct ResponseChoice {
139    pub index: usize,
140    pub finish_reason: Option<String>,
141    pub delta: Option<ResponseDelta>,
142    pub message: Option<ResponseDelta>,
143}
144
145#[derive(Debug, Deserialize)]
146pub struct ResponseDelta {
147    pub content: Option<String>,
148    pub role: Option<Role>,
149}
150
151#[derive(Deserialize)]
152struct ApiTokenResponse {
153    token: String,
154    expires_at: i64,
155}
156
157#[derive(Clone)]
158struct ApiToken {
159    api_key: String,
160    expires_at: DateTime<chrono::Utc>,
161}
162
163impl ApiToken {
164    pub fn remaining_seconds(&self) -> i64 {
165        self.expires_at
166            .timestamp()
167            .saturating_sub(chrono::Utc::now().timestamp())
168    }
169}
170
171impl TryFrom<ApiTokenResponse> for ApiToken {
172    type Error = anyhow::Error;
173
174    fn try_from(response: ApiTokenResponse) -> Result<Self, Self::Error> {
175        let expires_at = DateTime::from_timestamp(response.expires_at, 0)
176            .ok_or_else(|| anyhow!("invalid expires_at"))?;
177
178        Ok(Self {
179            api_key: response.token,
180            expires_at,
181        })
182    }
183}
184
185struct GlobalCopilotChat(gpui::Model<CopilotChat>);
186
187impl Global for GlobalCopilotChat {}
188
189pub struct CopilotChat {
190    oauth_token: Option<String>,
191    api_token: Option<ApiToken>,
192    client: Arc<dyn HttpClient>,
193}
194
195pub fn init(fs: Arc<dyn Fs>, client: Arc<dyn HttpClient>, cx: &mut AppContext) {
196    let copilot_chat = cx.new_model(|cx| CopilotChat::new(fs, client, cx));
197    cx.set_global(GlobalCopilotChat(copilot_chat));
198}
199
200fn copilot_chat_config_dir() -> &'static PathBuf {
201    static COPILOT_CHAT_CONFIG_DIR: OnceLock<PathBuf> = OnceLock::new();
202
203    COPILOT_CHAT_CONFIG_DIR.get_or_init(|| {
204        if cfg!(target_os = "windows") {
205            home_dir().join("AppData").join("Local")
206        } else {
207            home_dir().join(".config")
208        }
209        .join("github-copilot")
210    })
211}
212
213fn copilot_chat_config_paths() -> [PathBuf; 2] {
214    let base_dir = copilot_chat_config_dir();
215    [base_dir.join("hosts.json"), base_dir.join("apps.json")]
216}
217
218impl CopilotChat {
219    pub fn global(cx: &AppContext) -> Option<gpui::Model<Self>> {
220        cx.try_global::<GlobalCopilotChat>()
221            .map(|model| model.0.clone())
222    }
223
224    pub fn new(fs: Arc<dyn Fs>, client: Arc<dyn HttpClient>, cx: &AppContext) -> Self {
225        let config_paths = copilot_chat_config_paths();
226
227        let resolve_config_path = {
228            let fs = fs.clone();
229            async move {
230                for config_path in config_paths.iter() {
231                    if fs.metadata(config_path).await.is_ok_and(|v| v.is_some()) {
232                        return config_path.clone();
233                    }
234                }
235                config_paths[0].clone()
236            }
237        };
238
239        cx.spawn(|cx| async move {
240            let config_file = resolve_config_path.await;
241            let mut config_file_rx = watch_config_file(cx.background_executor(), fs, config_file);
242
243            while let Some(contents) = config_file_rx.next().await {
244                let oauth_token = extract_oauth_token(contents);
245
246                cx.update(|cx| {
247                    if let Some(this) = Self::global(cx).as_ref() {
248                        this.update(cx, |this, cx| {
249                            this.oauth_token = oauth_token;
250                            cx.notify();
251                        });
252                    }
253                })?;
254            }
255            anyhow::Ok(())
256        })
257        .detach_and_log_err(cx);
258
259        Self {
260            oauth_token: None,
261            api_token: None,
262            client,
263        }
264    }
265
266    pub fn is_authenticated(&self) -> bool {
267        self.oauth_token.is_some()
268    }
269
270    pub async fn stream_completion(
271        request: Request,
272        mut cx: AsyncAppContext,
273    ) -> Result<BoxStream<'static, Result<ResponseEvent>>> {
274        let Some(this) = cx.update(|cx| Self::global(cx)).ok().flatten() else {
275            return Err(anyhow!("Copilot chat is not enabled"));
276        };
277
278        let (oauth_token, api_token, client) = this.read_with(&cx, |this, _| {
279            (
280                this.oauth_token.clone(),
281                this.api_token.clone(),
282                this.client.clone(),
283            )
284        })?;
285
286        let oauth_token = oauth_token.ok_or_else(|| anyhow!("No OAuth token available"))?;
287
288        let token = match api_token {
289            Some(api_token) if api_token.remaining_seconds() > 5 * 60 => api_token.clone(),
290            _ => {
291                let token = request_api_token(&oauth_token, client.clone()).await?;
292                this.update(&mut cx, |this, cx| {
293                    this.api_token = Some(token.clone());
294                    cx.notify();
295                })?;
296                token
297            }
298        };
299
300        stream_completion(client.clone(), token.api_key, request).await
301    }
302}
303
304async fn request_api_token(oauth_token: &str, client: Arc<dyn HttpClient>) -> Result<ApiToken> {
305    let request_builder = HttpRequest::builder()
306        .method(Method::GET)
307        .uri(COPILOT_CHAT_AUTH_URL)
308        .header("Authorization", format!("token {}", oauth_token))
309        .header("Accept", "application/json");
310
311    let request = request_builder.body(AsyncBody::empty())?;
312
313    let mut response = client.send(request).await?;
314
315    if response.status().is_success() {
316        let mut body = Vec::new();
317        response.body_mut().read_to_end(&mut body).await?;
318
319        let body_str = std::str::from_utf8(&body)?;
320
321        let parsed: ApiTokenResponse = serde_json::from_str(body_str)?;
322        ApiToken::try_from(parsed)
323    } else {
324        let mut body = Vec::new();
325        response.body_mut().read_to_end(&mut body).await?;
326
327        let body_str = std::str::from_utf8(&body)?;
328
329        Err(anyhow!("Failed to request API token: {}", body_str))
330    }
331}
332
333fn extract_oauth_token(contents: String) -> Option<String> {
334    serde_json::from_str::<serde_json::Value>(&contents)
335        .map(|v| {
336            v.as_object().and_then(|obj| {
337                obj.iter().find_map(|(key, value)| {
338                    if key.starts_with("github.com") {
339                        value["oauth_token"].as_str().map(|v| v.to_string())
340                    } else {
341                        None
342                    }
343                })
344            })
345        })
346        .ok()
347        .flatten()
348}
349
350async fn stream_completion(
351    client: Arc<dyn HttpClient>,
352    api_key: String,
353    request: Request,
354) -> Result<BoxStream<'static, Result<ResponseEvent>>> {
355    let request_builder = HttpRequest::builder()
356        .method(Method::POST)
357        .uri(COPILOT_CHAT_COMPLETION_URL)
358        .header(
359            "Editor-Version",
360            format!(
361                "Zed/{}",
362                option_env!("CARGO_PKG_VERSION").unwrap_or("unknown")
363            ),
364        )
365        .header("Authorization", format!("Bearer {}", api_key))
366        .header("Content-Type", "application/json")
367        .header("Copilot-Integration-Id", "vscode-chat");
368
369    let is_streaming = request.stream;
370
371    let request = request_builder.body(AsyncBody::from(serde_json::to_string(&request)?))?;
372    let mut response = client.send(request).await?;
373
374    if !response.status().is_success() {
375        let mut body = Vec::new();
376        response.body_mut().read_to_end(&mut body).await?;
377        let body_str = std::str::from_utf8(&body)?;
378        return Err(anyhow!(
379            "Failed to connect to API: {} {}",
380            response.status(),
381            body_str
382        ));
383    }
384
385    if is_streaming {
386        let reader = BufReader::new(response.into_body());
387        Ok(reader
388            .lines()
389            .filter_map(|line| async move {
390                match line {
391                    Ok(line) => {
392                        let line = line.strip_prefix("data: ")?;
393                        if line.starts_with("[DONE]") {
394                            return None;
395                        }
396
397                        match serde_json::from_str::<ResponseEvent>(line) {
398                            Ok(response) => {
399                                if response.choices.first().is_none()
400                                    || response.choices.first().unwrap().finish_reason.is_some()
401                                {
402                                    None
403                                } else {
404                                    Some(Ok(response))
405                                }
406                            }
407                            Err(error) => Some(Err(anyhow!(error))),
408                        }
409                    }
410                    Err(error) => Some(Err(anyhow!(error))),
411                }
412            })
413            .boxed())
414    } else {
415        let mut body = Vec::new();
416        response.body_mut().read_to_end(&mut body).await?;
417        let body_str = std::str::from_utf8(&body)?;
418        let response: ResponseEvent = serde_json::from_str(body_str)?;
419
420        Ok(futures::stream::once(async move { Ok(response) }).boxed())
421    }
422}