prompts.rs

  1use anyhow::Result;
  2use assets::Assets;
  3use fs::Fs;
  4use futures::StreamExt;
  5use gpui::{App, AppContext as _, AssetSource};
  6use handlebars::{Handlebars, RenderError};
  7use language::{BufferSnapshot, LanguageName, Point};
  8use parking_lot::Mutex;
  9use serde::Serialize;
 10use std::{
 11    ops::Range,
 12    path::{Path, PathBuf},
 13    sync::Arc,
 14    time::Duration,
 15};
 16use text::LineEnding;
 17use util::{ResultExt, get_system_shell};
 18
 19use crate::UserPromptId;
 20
 21#[derive(Debug, Clone, Serialize)]
 22pub struct ProjectContext {
 23    pub worktrees: Vec<WorktreeContext>,
 24    /// Whether any worktree has a rules_file. Provided as a field because handlebars can't do this.
 25    pub has_rules: bool,
 26    pub user_rules: Vec<UserRulesContext>,
 27    /// `!user_rules.is_empty()` - provided as a field because handlebars can't do this.
 28    pub has_user_rules: bool,
 29    pub os: String,
 30    pub arch: String,
 31    pub shell: String,
 32}
 33
 34impl ProjectContext {
 35    pub fn new(worktrees: Vec<WorktreeContext>, default_user_rules: Vec<UserRulesContext>) -> Self {
 36        let has_rules = worktrees
 37            .iter()
 38            .any(|worktree| worktree.rules_file.is_some());
 39        Self {
 40            worktrees,
 41            has_rules,
 42            has_user_rules: !default_user_rules.is_empty(),
 43            user_rules: default_user_rules,
 44            os: std::env::consts::OS.to_string(),
 45            arch: std::env::consts::ARCH.to_string(),
 46            shell: get_system_shell(),
 47        }
 48    }
 49}
 50
 51#[derive(Debug, Clone, Serialize)]
 52pub struct UserRulesContext {
 53    pub uuid: UserPromptId,
 54    pub title: Option<String>,
 55    pub contents: String,
 56}
 57
 58#[derive(Debug, Clone, Serialize)]
 59pub struct WorktreeContext {
 60    pub root_name: String,
 61    pub rules_file: Option<RulesFileContext>,
 62}
 63
 64#[derive(Debug, Clone, Serialize)]
 65pub struct RulesFileContext {
 66    pub path_in_worktree: Arc<Path>,
 67    pub text: String,
 68    // This used for opening rules files. TODO: Since it isn't related to prompt templating, this
 69    // should be moved elsewhere.
 70    #[serde(skip)]
 71    pub project_entry_id: usize,
 72}
 73
 74#[derive(Serialize)]
 75pub struct ContentPromptDiagnosticContext {
 76    pub line_number: usize,
 77    pub error_message: String,
 78    pub code_content: String,
 79}
 80
 81#[derive(Serialize)]
 82pub struct ContentPromptContext {
 83    pub content_type: String,
 84    pub language_name: Option<String>,
 85    pub is_insert: bool,
 86    pub is_truncated: bool,
 87    pub document_content: String,
 88    pub user_prompt: String,
 89    pub rewrite_section: Option<String>,
 90    pub diagnostic_errors: Vec<ContentPromptDiagnosticContext>,
 91}
 92
 93#[derive(Serialize)]
 94pub struct TerminalAssistantPromptContext {
 95    pub os: String,
 96    pub arch: String,
 97    pub shell: Option<String>,
 98    pub working_directory: Option<String>,
 99    pub latest_output: Vec<String>,
100    pub user_prompt: String,
101}
102
103pub struct PromptLoadingParams<'a> {
104    pub fs: Arc<dyn Fs>,
105    pub repo_path: Option<PathBuf>,
106    pub cx: &'a gpui::App,
107}
108
109pub struct PromptBuilder {
110    handlebars: Arc<Mutex<Handlebars<'static>>>,
111}
112
113impl PromptBuilder {
114    pub fn load(fs: Arc<dyn Fs>, stdout_is_a_pty: bool, cx: &mut App) -> Arc<Self> {
115        Self::new(Some(PromptLoadingParams {
116            fs: fs.clone(),
117            repo_path: stdout_is_a_pty
118                .then(|| std::env::current_dir().log_err())
119                .flatten(),
120            cx,
121        }))
122        .log_err()
123        .map(Arc::new)
124        .unwrap_or_else(|| Arc::new(Self::new(None).unwrap()))
125    }
126
127    pub fn new(loading_params: Option<PromptLoadingParams>) -> Result<Self> {
128        let mut handlebars = Handlebars::new();
129        Self::register_built_in_templates(&mut handlebars)?;
130
131        let handlebars = Arc::new(Mutex::new(handlebars));
132
133        if let Some(params) = loading_params {
134            Self::watch_fs_for_template_overrides(params, handlebars.clone());
135        }
136
137        Ok(Self { handlebars })
138    }
139
140    /// Watches the filesystem for changes to prompt template overrides.
141    ///
142    /// This function sets up a file watcher on the prompt templates directory. It performs
143    /// an initial scan of the directory and registers any existing template overrides.
144    /// Then it continuously monitors for changes, reloading templates as they are
145    /// modified or added.
146    ///
147    /// If the templates directory doesn't exist initially, it waits for it to be created.
148    /// If the directory is removed, it restores the built-in templates and waits for the
149    /// directory to be recreated.
150    ///
151    /// # Arguments
152    ///
153    /// * `params` - A `PromptLoadingParams` struct containing the filesystem, repository path,
154    ///   and application context.
155    /// * `handlebars` - An `Arc<Mutex<Handlebars>>` for registering and updating templates.
156    fn watch_fs_for_template_overrides(
157        params: PromptLoadingParams,
158        handlebars: Arc<Mutex<Handlebars<'static>>>,
159    ) {
160        let templates_dir = paths::prompt_overrides_dir(params.repo_path.as_deref());
161        params.cx.background_spawn(async move {
162            let Some(parent_dir) = templates_dir.parent() else {
163                return;
164            };
165
166            let mut found_dir_once = false;
167            loop {
168                // Check if the templates directory exists and handle its status
169                // If it exists, log its presence and check if it's a symlink
170                // If it doesn't exist:
171                //   - Log that we're using built-in prompts
172                //   - Check if it's a broken symlink and log if so
173                //   - Set up a watcher to detect when it's created
174                // After the first check, set the `found_dir_once` flag
175                // This allows us to avoid logging when looping back around after deleting the prompt overrides directory.
176                let dir_status = params.fs.is_dir(&templates_dir).await;
177                let symlink_status = params.fs.read_link(&templates_dir).await.ok();
178                if dir_status {
179                    let mut log_message = format!("Prompt template overrides directory found at {}", templates_dir.display());
180                    if let Some(target) = symlink_status {
181                        log_message.push_str(" -> ");
182                        log_message.push_str(&target.display().to_string());
183                    }
184                    log::info!("{}.", log_message);
185                } else {
186                    if !found_dir_once {
187                        log::info!("No prompt template overrides directory found at {}. Using built-in prompts.", templates_dir.display());
188                        if let Some(target) = symlink_status {
189                            log::info!("Symlink found pointing to {}, but target is invalid.", target.display());
190                        }
191                    }
192
193                    if params.fs.is_dir(parent_dir).await {
194                        let (mut changes, _watcher) = params.fs.watch(parent_dir, Duration::from_secs(1)).await;
195                        while let Some(changed_paths) = changes.next().await {
196                            if changed_paths.iter().any(|p| &p.path == &templates_dir) {
197                                let mut log_message = format!("Prompt template overrides directory detected at {}", templates_dir.display());
198                                if let Ok(target) = params.fs.read_link(&templates_dir).await {
199                                    log_message.push_str(" -> ");
200                                    log_message.push_str(&target.display().to_string());
201                                }
202                                log::info!("{}.", log_message);
203                                break;
204                            }
205                        }
206                    } else {
207                        return;
208                    }
209                }
210
211                found_dir_once = true;
212
213                // Initial scan of the prompt overrides directory
214                if let Ok(mut entries) = params.fs.read_dir(&templates_dir).await {
215                    while let Some(Ok(file_path)) = entries.next().await {
216                        if file_path.to_string_lossy().ends_with(".hbs") {
217                            if let Ok(content) = params.fs.load(&file_path).await {
218                                let file_name = file_path.file_stem().unwrap().to_string_lossy();
219                                log::debug!("Registering prompt template override: {}", file_name);
220                                handlebars.lock().register_template_string(&file_name, content).log_err();
221                            }
222                        }
223                    }
224                }
225
226                // Watch both the parent directory and the template overrides directory:
227                // - Monitor the parent directory to detect if the template overrides directory is deleted.
228                // - Monitor the template overrides directory to re-register templates when they change.
229                // Combine both watch streams into a single stream.
230                let (parent_changes, parent_watcher) = params.fs.watch(parent_dir, Duration::from_secs(1)).await;
231                let (changes, watcher) = params.fs.watch(&templates_dir, Duration::from_secs(1)).await;
232                let mut combined_changes = futures::stream::select(changes, parent_changes);
233
234                while let Some(changed_paths) = combined_changes.next().await {
235                    if changed_paths.iter().any(|p| &p.path == &templates_dir) {
236                        if !params.fs.is_dir(&templates_dir).await {
237                            log::info!("Prompt template overrides directory removed. Restoring built-in prompt templates.");
238                            Self::register_built_in_templates(&mut handlebars.lock()).log_err();
239                            break;
240                        }
241                    }
242                    for event in changed_paths {
243                        if event.path.starts_with(&templates_dir) && event.path.extension().map_or(false, |ext| ext == "hbs") {
244                            log::info!("Reloading prompt template override: {}", event.path.display());
245                            if let Some(content) = params.fs.load(&event.path).await.log_err() {
246                                let file_name = event.path.file_stem().unwrap().to_string_lossy();
247                                handlebars.lock().register_template_string(&file_name, content).log_err();
248                            }
249                        }
250                    }
251                }
252
253                drop(watcher);
254                drop(parent_watcher);
255            }
256        })
257            .detach();
258    }
259
260    fn register_built_in_templates(handlebars: &mut Handlebars) -> Result<()> {
261        for path in Assets.list("prompts")? {
262            if let Some(id) = path
263                .split('/')
264                .next_back()
265                .and_then(|s| s.strip_suffix(".hbs"))
266            {
267                if let Some(prompt) = Assets.load(path.as_ref()).log_err().flatten() {
268                    log::debug!("Registering built-in prompt template: {}", id);
269                    let prompt = String::from_utf8_lossy(prompt.as_ref());
270                    handlebars.register_template_string(id, LineEnding::normalize_cow(prompt))?
271                }
272            }
273        }
274
275        Ok(())
276    }
277
278    pub fn generate_assistant_system_prompt(
279        &self,
280        context: &ProjectContext,
281    ) -> Result<String, RenderError> {
282        self.handlebars
283            .lock()
284            .render("assistant_system_prompt", context)
285    }
286
287    pub fn generate_inline_transformation_prompt(
288        &self,
289        user_prompt: String,
290        language_name: Option<&LanguageName>,
291        buffer: BufferSnapshot,
292        range: Range<usize>,
293    ) -> Result<String, RenderError> {
294        let content_type = match language_name.as_ref().map(|l| l.as_ref()) {
295            None | Some("Markdown" | "Plain Text") => "text",
296            Some(_) => "code",
297        };
298
299        const MAX_CTX: usize = 50000;
300        let is_insert = range.is_empty();
301        let mut is_truncated = false;
302
303        let before_range = 0..range.start;
304        let truncated_before = if before_range.len() > MAX_CTX {
305            is_truncated = true;
306            let start = buffer.clip_offset(range.start - MAX_CTX, text::Bias::Right);
307            start..range.start
308        } else {
309            before_range
310        };
311
312        let after_range = range.end..buffer.len();
313        let truncated_after = if after_range.len() > MAX_CTX {
314            is_truncated = true;
315            let end = buffer.clip_offset(range.end + MAX_CTX, text::Bias::Left);
316            range.end..end
317        } else {
318            after_range
319        };
320
321        let mut document_content = String::new();
322        for chunk in buffer.text_for_range(truncated_before) {
323            document_content.push_str(chunk);
324        }
325        if is_insert {
326            document_content.push_str("<insert_here></insert_here>");
327        } else {
328            document_content.push_str("<rewrite_this>\n");
329            for chunk in buffer.text_for_range(range.clone()) {
330                document_content.push_str(chunk);
331            }
332            document_content.push_str("\n</rewrite_this>");
333        }
334        for chunk in buffer.text_for_range(truncated_after) {
335            document_content.push_str(chunk);
336        }
337
338        let rewrite_section = if !is_insert {
339            let mut section = String::new();
340            for chunk in buffer.text_for_range(range.clone()) {
341                section.push_str(chunk);
342            }
343            Some(section)
344        } else {
345            None
346        };
347        let diagnostics = buffer.diagnostics_in_range::<_, Point>(range, false);
348        let diagnostic_errors: Vec<ContentPromptDiagnosticContext> = diagnostics
349            .map(|entry| {
350                let start = entry.range.start;
351                ContentPromptDiagnosticContext {
352                    line_number: (start.row + 1) as usize,
353                    error_message: entry.diagnostic.message.clone(),
354                    code_content: buffer.text_for_range(entry.range.clone()).collect(),
355                }
356            })
357            .collect();
358
359        let context = ContentPromptContext {
360            content_type: content_type.to_string(),
361            language_name: language_name.map(|s| s.to_string()),
362            is_insert,
363            is_truncated,
364            document_content,
365            user_prompt,
366            rewrite_section,
367            diagnostic_errors,
368        };
369        self.handlebars.lock().render("content_prompt", &context)
370    }
371
372    pub fn generate_terminal_assistant_prompt(
373        &self,
374        user_prompt: &str,
375        shell: Option<&str>,
376        working_directory: Option<&str>,
377        latest_output: &[String],
378    ) -> Result<String, RenderError> {
379        let context = TerminalAssistantPromptContext {
380            os: std::env::consts::OS.to_string(),
381            arch: std::env::consts::ARCH.to_string(),
382            shell: shell.map(|s| s.to_string()),
383            working_directory: working_directory.map(|s| s.to_string()),
384            latest_output: latest_output.to_vec(),
385            user_prompt: user_prompt.to_string(),
386        };
387
388        self.handlebars
389            .lock()
390            .render("terminal_assistant_prompt", &context)
391    }
392
393    pub fn generate_suggest_edits_prompt(&self) -> Result<String, RenderError> {
394        self.handlebars.lock().render("suggest_edits", &())
395    }
396}
397
398#[cfg(test)]
399mod test {
400    use super::*;
401    use uuid::Uuid;
402
403    #[test]
404    fn test_assistant_system_prompt_renders() {
405        let worktrees = vec![WorktreeContext {
406            root_name: "path".into(),
407            rules_file: Some(RulesFileContext {
408                path_in_worktree: Path::new(".rules").into(),
409                text: "".into(),
410                project_entry_id: 0,
411            }),
412        }];
413        let default_user_rules = vec![UserRulesContext {
414            uuid: UserPromptId(Uuid::nil()),
415            title: Some("Rules title".into()),
416            contents: "Rules contents".into(),
417        }];
418        let project_context = ProjectContext::new(worktrees, default_user_rules);
419        PromptBuilder::new(None)
420            .unwrap()
421            .generate_assistant_system_prompt(&project_context)
422            .unwrap();
423    }
424}