supermaven_completion_provider.rs

  1use crate::{Supermaven, SupermavenCompletionStateId};
  2use anyhow::Result;
  3use futures::StreamExt as _;
  4use gpui::{App, Context, Entity, EntityId, Task};
  5use inline_completion::{Direction, InlineCompletion, InlineCompletionProvider};
  6use language::{Anchor, Buffer, BufferSnapshot};
  7use std::{
  8    ops::{AddAssign, Range},
  9    path::Path,
 10    time::Duration,
 11};
 12use text::{ToOffset, ToPoint};
 13use unicode_segmentation::UnicodeSegmentation;
 14
 15pub const DEBOUNCE_TIMEOUT: Duration = Duration::from_millis(75);
 16
 17pub struct SupermavenCompletionProvider {
 18    supermaven: Entity<Supermaven>,
 19    buffer_id: Option<EntityId>,
 20    completion_id: Option<SupermavenCompletionStateId>,
 21    file_extension: Option<String>,
 22    pending_refresh: Option<Task<Result<()>>>,
 23}
 24
 25impl SupermavenCompletionProvider {
 26    pub fn new(supermaven: Entity<Supermaven>) -> Self {
 27        Self {
 28            supermaven,
 29            buffer_id: None,
 30            completion_id: None,
 31            file_extension: None,
 32            pending_refresh: None,
 33        }
 34    }
 35}
 36
 37// Computes the edit prediction from the difference between the completion text.
 38// this is defined by greedily matching the buffer text against the completion text, with any leftover buffer placed at the end.
 39// for example, given the completion text "moo cows are cool" and the buffer text "cowsre pool", the completion state would be
 40// the inlays "moo ", " a", and "cool" which will render as "[moo ]cows[ a]re [cool]pool" in the editor.
 41fn completion_from_diff(
 42    snapshot: BufferSnapshot,
 43    completion_text: &str,
 44    position: Anchor,
 45    delete_range: Range<Anchor>,
 46) -> InlineCompletion {
 47    let buffer_text = snapshot
 48        .text_for_range(delete_range.clone())
 49        .collect::<String>();
 50
 51    let mut edits: Vec<(Range<language::Anchor>, String)> = Vec::new();
 52
 53    let completion_graphemes: Vec<&str> = completion_text.graphemes(true).collect();
 54    let buffer_graphemes: Vec<&str> = buffer_text.graphemes(true).collect();
 55
 56    let mut offset = position.to_offset(&snapshot);
 57
 58    let mut i = 0;
 59    let mut j = 0;
 60    while i < completion_graphemes.len() && j < buffer_graphemes.len() {
 61        // find the next instance of the buffer text in the completion text.
 62        let k = completion_graphemes[i..]
 63            .iter()
 64            .position(|c| *c == buffer_graphemes[j]);
 65        match k {
 66            Some(k) => {
 67                if k != 0 {
 68                    let offset = snapshot.anchor_after(offset);
 69                    // the range from the current position to item is an inlay.
 70                    let edit = (offset..offset, completion_graphemes[i..i + k].join(""));
 71                    edits.push(edit);
 72                }
 73                i += k + 1;
 74                j += 1;
 75                offset.add_assign(buffer_graphemes[j - 1].len());
 76            }
 77            None => {
 78                // there are no more matching completions, so drop the remaining
 79                // completion text as an inlay.
 80                break;
 81            }
 82        }
 83    }
 84
 85    if j == buffer_graphemes.len() && i < completion_graphemes.len() {
 86        let offset = snapshot.anchor_after(offset);
 87        // there is leftover completion text, so drop it as an inlay.
 88        let edit_range = offset..offset;
 89        let edit_text = completion_graphemes[i..].join("");
 90        edits.push((edit_range, edit_text));
 91    }
 92
 93    InlineCompletion {
 94        edits,
 95        edit_preview: None,
 96    }
 97}
 98
 99impl InlineCompletionProvider for SupermavenCompletionProvider {
100    fn name() -> &'static str {
101        "supermaven"
102    }
103
104    fn display_name() -> &'static str {
105        "Supermaven"
106    }
107
108    fn show_completions_in_menu() -> bool {
109        false
110    }
111
112    fn show_completions_in_normal_mode() -> bool {
113        false
114    }
115
116    fn is_enabled(&self, _buffer: &Entity<Buffer>, _cursor_position: Anchor, cx: &App) -> bool {
117        self.supermaven.read(cx).is_enabled()
118    }
119
120    fn is_refreshing(&self) -> bool {
121        self.pending_refresh.is_some()
122    }
123
124    fn refresh(
125        &mut self,
126        buffer_handle: Entity<Buffer>,
127        cursor_position: Anchor,
128        debounce: bool,
129        cx: &mut Context<Self>,
130    ) {
131        let Some(mut completion) = self.supermaven.update(cx, |supermaven, cx| {
132            supermaven.complete(&buffer_handle, cursor_position, cx)
133        }) else {
134            return;
135        };
136
137        self.pending_refresh = Some(cx.spawn(|this, mut cx| async move {
138            if debounce {
139                cx.background_executor().timer(DEBOUNCE_TIMEOUT).await;
140            }
141
142            while let Some(()) = completion.updates.next().await {
143                this.update(&mut cx, |this, cx| {
144                    this.completion_id = Some(completion.id);
145                    this.buffer_id = Some(buffer_handle.entity_id());
146                    this.file_extension = buffer_handle.read(cx).file().and_then(|file| {
147                        Some(
148                            Path::new(file.file_name(cx))
149                                .extension()?
150                                .to_str()?
151                                .to_string(),
152                        )
153                    });
154                    this.pending_refresh = None;
155                    cx.notify();
156                })?;
157            }
158            Ok(())
159        }));
160    }
161
162    fn cycle(
163        &mut self,
164        _buffer: Entity<Buffer>,
165        _cursor_position: Anchor,
166        _direction: Direction,
167        _cx: &mut Context<Self>,
168    ) {
169    }
170
171    fn accept(&mut self, _cx: &mut Context<Self>) {
172        self.pending_refresh = None;
173        self.completion_id = None;
174    }
175
176    fn discard(&mut self, _cx: &mut Context<Self>) {
177        self.pending_refresh = None;
178        self.completion_id = None;
179    }
180
181    fn suggest(
182        &mut self,
183        buffer: &Entity<Buffer>,
184        cursor_position: Anchor,
185        cx: &mut Context<Self>,
186    ) -> Option<InlineCompletion> {
187        let completion_text = self
188            .supermaven
189            .read(cx)
190            .completion(buffer, cursor_position, cx)?;
191
192        let completion_text = trim_to_end_of_line_unless_leading_newline(completion_text);
193
194        let completion_text = completion_text.trim_end();
195
196        if !completion_text.trim().is_empty() {
197            let snapshot = buffer.read(cx).snapshot();
198            let mut point = cursor_position.to_point(&snapshot);
199            point.column = snapshot.line_len(point.row);
200            let range = cursor_position..snapshot.anchor_after(point);
201            Some(completion_from_diff(
202                snapshot,
203                completion_text,
204                cursor_position,
205                range,
206            ))
207        } else {
208            None
209        }
210    }
211}
212
213fn trim_to_end_of_line_unless_leading_newline(text: &str) -> &str {
214    if has_leading_newline(text) {
215        text
216    } else if let Some(i) = text.find('\n') {
217        &text[..i]
218    } else {
219        text
220    }
221}
222
223fn has_leading_newline(text: &str) -> bool {
224    for c in text.chars() {
225        if c == '\n' {
226            return true;
227        }
228        if !c.is_whitespace() {
229            return false;
230        }
231    }
232    false
233}