WIP

crates/language2/src/outline.rs

@@ -0,0 +1,138 @@
+use fuzzy::{StringMatch, StringMatchCandidate};
+use gpui2::{Executor, HighlightStyle};
+use std::{ops::Range, sync::Arc};
+
+#[derive(Debug)]
+pub struct Outline<T> {
+    pub items: Vec<OutlineItem<T>>,
+    candidates: Vec<StringMatchCandidate>,
+    path_candidates: Vec<StringMatchCandidate>,
+    path_candidate_prefixes: Vec<usize>,
+}
+
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub struct OutlineItem<T> {
+    pub depth: usize,
+    pub range: Range<T>,
+    pub text: String,
+    pub highlight_ranges: Vec<(Range<usize>, HighlightStyle)>,
+    pub name_ranges: Vec<Range<usize>>,
+}
+
+impl<T> Outline<T> {
+    pub fn new(items: Vec<OutlineItem<T>>) -> Self {
+        let mut candidates = Vec::new();
+        let mut path_candidates = Vec::new();
+        let mut path_candidate_prefixes = Vec::new();
+        let mut path_text = String::new();
+        let mut path_stack = Vec::new();
+
+        for (id, item) in items.iter().enumerate() {
+            if item.depth < path_stack.len() {
+                path_stack.truncate(item.depth);
+                path_text.truncate(path_stack.last().copied().unwrap_or(0));
+            }
+            if !path_text.is_empty() {
+                path_text.push(' ');
+            }
+            path_candidate_prefixes.push(path_text.len());
+            path_text.push_str(&item.text);
+            path_stack.push(path_text.len());
+
+            let candidate_text = item
+                .name_ranges
+                .iter()
+                .map(|range| &item.text[range.start as usize..range.end as usize])
+                .collect::<String>();
+
+            path_candidates.push(StringMatchCandidate::new(id, path_text.clone()));
+            candidates.push(StringMatchCandidate::new(id, candidate_text));
+        }
+
+        Self {
+            candidates,
+            path_candidates,
+            path_candidate_prefixes,
+            items,
+        }
+    }
+
+    pub async fn search(&self, query: &str, executor: Executor) -> Vec<StringMatch> {
+        let query = query.trim_start();
+        let is_path_query = query.contains(' ');
+        let smart_case = query.chars().any(|c| c.is_uppercase());
+        let mut matches = fuzzy::match_strings(
+            if is_path_query {
+                &self.path_candidates
+            } else {
+                &self.candidates
+            },
+            query,
+            smart_case,
+            100,
+            &Default::default(),
+            executor.clone(),
+        )
+        .await;
+        matches.sort_unstable_by_key(|m| m.candidate_id);
+
+        let mut tree_matches = Vec::new();
+
+        let mut prev_item_ix = 0;
+        for mut string_match in matches {
+            let outline_match = &self.items[string_match.candidate_id];
+
+            if is_path_query {
+                let prefix_len = self.path_candidate_prefixes[string_match.candidate_id];
+                string_match
+                    .positions
+                    .retain(|position| *position >= prefix_len);
+                for position in &mut string_match.positions {
+                    *position -= prefix_len;
+                }
+            } else {
+                let mut name_ranges = outline_match.name_ranges.iter();
+                let mut name_range = name_ranges.next().unwrap();
+                let mut preceding_ranges_len = 0;
+                for position in &mut string_match.positions {
+                    while *position >= preceding_ranges_len + name_range.len() as usize {
+                        preceding_ranges_len += name_range.len();
+                        name_range = name_ranges.next().unwrap();
+                    }
+                    *position = name_range.start as usize + (*position - preceding_ranges_len);
+                }
+            }
+
+            let insertion_ix = tree_matches.len();
+            let mut cur_depth = outline_match.depth;
+            for (ix, item) in self.items[prev_item_ix..string_match.candidate_id]
+                .iter()
+                .enumerate()
+                .rev()
+            {
+                if cur_depth == 0 {
+                    break;
+                }
+
+                let candidate_index = ix + prev_item_ix;
+                if item.depth == cur_depth - 1 {
+                    tree_matches.insert(
+                        insertion_ix,
+                        StringMatch {
+                            candidate_id: candidate_index,
+                            score: Default::default(),
+                            positions: Default::default(),
+                            string: Default::default(),
+                        },
+                    );
+                    cur_depth -= 1;
+                }
+            }
+
+            prev_item_ix = string_match.candidate_id + 1;
+            tree_matches.push(string_match);
+        }
+
+        tree_matches
+    }
+}