prompts.rs

  1use anyhow::Result;
  2use assets::Assets;
  3use fs::Fs;
  4use futures::StreamExt;
  5use gpui::{App, AssetSource};
  6use handlebars::{Handlebars, RenderError};
  7use language::{BufferSnapshot, LanguageName, Point};
  8use parking_lot::Mutex;
  9use serde::Serialize;
 10use std::{ops::Range, path::PathBuf, sync::Arc, time::Duration};
 11use text::LineEnding;
 12use util::ResultExt;
 13
 14#[derive(Serialize)]
 15pub struct ContentPromptDiagnosticContext {
 16    pub line_number: usize,
 17    pub error_message: String,
 18    pub code_content: String,
 19}
 20
 21#[derive(Serialize)]
 22pub struct ContentPromptContext {
 23    pub content_type: String,
 24    pub language_name: Option<String>,
 25    pub is_insert: bool,
 26    pub is_truncated: bool,
 27    pub document_content: String,
 28    pub user_prompt: String,
 29    pub rewrite_section: Option<String>,
 30    pub diagnostic_errors: Vec<ContentPromptDiagnosticContext>,
 31}
 32
 33#[derive(Serialize)]
 34pub struct TerminalAssistantPromptContext {
 35    pub os: String,
 36    pub arch: String,
 37    pub shell: Option<String>,
 38    pub working_directory: Option<String>,
 39    pub latest_output: Vec<String>,
 40    pub user_prompt: String,
 41}
 42
 43#[derive(Serialize)]
 44pub struct ProjectSlashCommandPromptContext {
 45    pub context_buffer: String,
 46}
 47
 48pub struct PromptLoadingParams<'a> {
 49    pub fs: Arc<dyn Fs>,
 50    pub repo_path: Option<PathBuf>,
 51    pub cx: &'a gpui::App,
 52}
 53
 54pub struct PromptBuilder {
 55    handlebars: Arc<Mutex<Handlebars<'static>>>,
 56}
 57
 58impl PromptBuilder {
 59    pub fn load(fs: Arc<dyn Fs>, stdout_is_a_pty: bool, cx: &mut App) -> Arc<Self> {
 60        Self::new(Some(PromptLoadingParams {
 61            fs: fs.clone(),
 62            repo_path: stdout_is_a_pty
 63                .then(|| std::env::current_dir().log_err())
 64                .flatten(),
 65            cx,
 66        }))
 67        .log_err()
 68        .map(Arc::new)
 69        .unwrap_or_else(|| Arc::new(Self::new(None).unwrap()))
 70    }
 71
 72    pub fn new(loading_params: Option<PromptLoadingParams>) -> Result<Self> {
 73        let mut handlebars = Handlebars::new();
 74        Self::register_built_in_templates(&mut handlebars)?;
 75
 76        let handlebars = Arc::new(Mutex::new(handlebars));
 77
 78        if let Some(params) = loading_params {
 79            Self::watch_fs_for_template_overrides(params, handlebars.clone());
 80        }
 81
 82        Ok(Self { handlebars })
 83    }
 84
 85    /// Watches the filesystem for changes to prompt template overrides.
 86    ///
 87    /// This function sets up a file watcher on the prompt templates directory. It performs
 88    /// an initial scan of the directory and registers any existing template overrides.
 89    /// Then it continuously monitors for changes, reloading templates as they are
 90    /// modified or added.
 91    ///
 92    /// If the templates directory doesn't exist initially, it waits for it to be created.
 93    /// If the directory is removed, it restores the built-in templates and waits for the
 94    /// directory to be recreated.
 95    ///
 96    /// # Arguments
 97    ///
 98    /// * `params` - A `PromptLoadingParams` struct containing the filesystem, repository path,
 99    ///   and application context.
100    /// * `handlebars` - An `Arc<Mutex<Handlebars>>` for registering and updating templates.
101    fn watch_fs_for_template_overrides(
102        params: PromptLoadingParams,
103        handlebars: Arc<Mutex<Handlebars<'static>>>,
104    ) {
105        let templates_dir = paths::prompt_overrides_dir(params.repo_path.as_deref());
106        params.cx.background_executor()
107            .spawn(async move {
108                let Some(parent_dir) = templates_dir.parent() else {
109                    return;
110                };
111
112                let mut found_dir_once = false;
113                loop {
114                    // Check if the templates directory exists and handle its status
115                    // If it exists, log its presence and check if it's a symlink
116                    // If it doesn't exist:
117                    //   - Log that we're using built-in prompts
118                    //   - Check if it's a broken symlink and log if so
119                    //   - Set up a watcher to detect when it's created
120                    // After the first check, set the `found_dir_once` flag
121                    // This allows us to avoid logging when looping back around after deleting the prompt overrides directory.
122                    let dir_status = params.fs.is_dir(&templates_dir).await;
123                    let symlink_status = params.fs.read_link(&templates_dir).await.ok();
124                    if dir_status {
125                        let mut log_message = format!("Prompt template overrides directory found at {}", templates_dir.display());
126                        if let Some(target) = symlink_status {
127                            log_message.push_str(" -> ");
128                            log_message.push_str(&target.display().to_string());
129                        }
130                        log::info!("{}.", log_message);
131                    } else {
132                        if !found_dir_once {
133                            log::info!("No prompt template overrides directory found at {}. Using built-in prompts.", templates_dir.display());
134                            if let Some(target) = symlink_status {
135                                log::info!("Symlink found pointing to {}, but target is invalid.", target.display());
136                            }
137                        }
138
139                        if params.fs.is_dir(parent_dir).await {
140                            let (mut changes, _watcher) = params.fs.watch(parent_dir, Duration::from_secs(1)).await;
141                            while let Some(changed_paths) = changes.next().await {
142                                if changed_paths.iter().any(|p| &p.path == &templates_dir) {
143                                    let mut log_message = format!("Prompt template overrides directory detected at {}", templates_dir.display());
144                                    if let Ok(target) = params.fs.read_link(&templates_dir).await {
145                                        log_message.push_str(" -> ");
146                                        log_message.push_str(&target.display().to_string());
147                                    }
148                                    log::info!("{}.", log_message);
149                                    break;
150                                }
151                            }
152                        } else {
153                            return;
154                        }
155                    }
156
157                    found_dir_once = true;
158
159                    // Initial scan of the prompt overrides directory
160                    if let Ok(mut entries) = params.fs.read_dir(&templates_dir).await {
161                        while let Some(Ok(file_path)) = entries.next().await {
162                            if file_path.to_string_lossy().ends_with(".hbs") {
163                                if let Ok(content) = params.fs.load(&file_path).await {
164                                    let file_name = file_path.file_stem().unwrap().to_string_lossy();
165                                    log::debug!("Registering prompt template override: {}", file_name);
166                                    handlebars.lock().register_template_string(&file_name, content).log_err();
167                                }
168                            }
169                        }
170                    }
171
172                    // Watch both the parent directory and the template overrides directory:
173                    // - Monitor the parent directory to detect if the template overrides directory is deleted.
174                    // - Monitor the template overrides directory to re-register templates when they change.
175                    // Combine both watch streams into a single stream.
176                    let (parent_changes, parent_watcher) = params.fs.watch(parent_dir, Duration::from_secs(1)).await;
177                    let (changes, watcher) = params.fs.watch(&templates_dir, Duration::from_secs(1)).await;
178                    let mut combined_changes = futures::stream::select(changes, parent_changes);
179
180                    while let Some(changed_paths) = combined_changes.next().await {
181                        if changed_paths.iter().any(|p| &p.path == &templates_dir) {
182                            if !params.fs.is_dir(&templates_dir).await {
183                                log::info!("Prompt template overrides directory removed. Restoring built-in prompt templates.");
184                                Self::register_built_in_templates(&mut handlebars.lock()).log_err();
185                                break;
186                            }
187                        }
188                        for event in changed_paths {
189                            if event.path.starts_with(&templates_dir) && event.path.extension().map_or(false, |ext| ext == "hbs") {
190                                log::info!("Reloading prompt template override: {}", event.path.display());
191                                if let Some(content) = params.fs.load(&event.path).await.log_err() {
192                                    let file_name = event.path.file_stem().unwrap().to_string_lossy();
193                                    handlebars.lock().register_template_string(&file_name, content).log_err();
194                                }
195                            }
196                        }
197                    }
198
199                    drop(watcher);
200                    drop(parent_watcher);
201                }
202            })
203            .detach();
204    }
205
206    fn register_built_in_templates(handlebars: &mut Handlebars) -> Result<()> {
207        for path in Assets.list("prompts")? {
208            if let Some(id) = path.split('/').last().and_then(|s| s.strip_suffix(".hbs")) {
209                if let Some(prompt) = Assets.load(path.as_ref()).log_err().flatten() {
210                    log::debug!("Registering built-in prompt template: {}", id);
211                    let prompt = String::from_utf8_lossy(prompt.as_ref());
212                    handlebars.register_template_string(id, LineEnding::normalize_cow(prompt))?
213                }
214            }
215        }
216
217        Ok(())
218    }
219
220    pub fn generate_inline_transformation_prompt(
221        &self,
222        user_prompt: String,
223        language_name: Option<&LanguageName>,
224        buffer: BufferSnapshot,
225        range: Range<usize>,
226    ) -> Result<String, RenderError> {
227        let content_type = match language_name.as_ref().map(|l| l.as_ref()) {
228            None | Some("Markdown" | "Plain Text") => "text",
229            Some(_) => "code",
230        };
231
232        const MAX_CTX: usize = 50000;
233        let is_insert = range.is_empty();
234        let mut is_truncated = false;
235
236        let before_range = 0..range.start;
237        let truncated_before = if before_range.len() > MAX_CTX {
238            is_truncated = true;
239            let start = buffer.clip_offset(range.start - MAX_CTX, text::Bias::Right);
240            start..range.start
241        } else {
242            before_range
243        };
244
245        let after_range = range.end..buffer.len();
246        let truncated_after = if after_range.len() > MAX_CTX {
247            is_truncated = true;
248            let end = buffer.clip_offset(range.end + MAX_CTX, text::Bias::Left);
249            range.end..end
250        } else {
251            after_range
252        };
253
254        let mut document_content = String::new();
255        for chunk in buffer.text_for_range(truncated_before) {
256            document_content.push_str(chunk);
257        }
258        if is_insert {
259            document_content.push_str("<insert_here></insert_here>");
260        } else {
261            document_content.push_str("<rewrite_this>\n");
262            for chunk in buffer.text_for_range(range.clone()) {
263                document_content.push_str(chunk);
264            }
265            document_content.push_str("\n</rewrite_this>");
266        }
267        for chunk in buffer.text_for_range(truncated_after) {
268            document_content.push_str(chunk);
269        }
270
271        let rewrite_section = if !is_insert {
272            let mut section = String::new();
273            for chunk in buffer.text_for_range(range.clone()) {
274                section.push_str(chunk);
275            }
276            Some(section)
277        } else {
278            None
279        };
280        let diagnostics = buffer.diagnostics_in_range::<_, Point>(range, false);
281        let diagnostic_errors: Vec<ContentPromptDiagnosticContext> = diagnostics
282            .map(|entry| {
283                let start = entry.range.start;
284                ContentPromptDiagnosticContext {
285                    line_number: (start.row + 1) as usize,
286                    error_message: entry.diagnostic.message.clone(),
287                    code_content: buffer.text_for_range(entry.range.clone()).collect(),
288                }
289            })
290            .collect();
291
292        let context = ContentPromptContext {
293            content_type: content_type.to_string(),
294            language_name: language_name.map(|s| s.to_string()),
295            is_insert,
296            is_truncated,
297            document_content,
298            user_prompt,
299            rewrite_section,
300            diagnostic_errors,
301        };
302        self.handlebars.lock().render("content_prompt", &context)
303    }
304
305    pub fn generate_terminal_assistant_prompt(
306        &self,
307        user_prompt: &str,
308        shell: Option<&str>,
309        working_directory: Option<&str>,
310        latest_output: &[String],
311    ) -> Result<String, RenderError> {
312        let context = TerminalAssistantPromptContext {
313            os: std::env::consts::OS.to_string(),
314            arch: std::env::consts::ARCH.to_string(),
315            shell: shell.map(|s| s.to_string()),
316            working_directory: working_directory.map(|s| s.to_string()),
317            latest_output: latest_output.to_vec(),
318            user_prompt: user_prompt.to_string(),
319        };
320
321        self.handlebars
322            .lock()
323            .render("terminal_assistant_prompt", &context)
324    }
325
326    pub fn generate_suggest_edits_prompt(&self) -> Result<String, RenderError> {
327        self.handlebars.lock().render("suggest_edits", &())
328    }
329
330    pub fn generate_project_slash_command_prompt(
331        &self,
332        context_buffer: String,
333    ) -> Result<String, RenderError> {
334        self.handlebars.lock().render(
335            "project_slash_command",
336            &ProjectSlashCommandPromptContext { context_buffer },
337        )
338    }
339}