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