From 4552bb70b9a72ec2f1d9f84a121969a474e6d8d4 Mon Sep 17 00:00:00 2001
From: Steve Dignam <steve@dignam.xyz>
Date: Tue, 6 Jan 2026 22:37:26 -0500
Subject: [PATCH] playground: expand selection support

---
 crates/squawk_wasm/src/lib.rs | 65 ++++++++++++++++++++++++++++++++++-
 playground/src/App.tsx        |  8 +++++
 playground/src/providers.tsx  | 32 +++++++++++++++++
 playground/src/squawk.tsx     | 15 ++++++++
 4 files changed, 119 insertions(+), 1 deletion(-)

diff --git a/crates/squawk_wasm/src/lib.rs b/crates/squawk_wasm/src/lib.rs
index b7250633..62570506 100644
--- a/crates/squawk_wasm/src/lib.rs
+++ b/crates/squawk_wasm/src/lib.rs
@@ -1,6 +1,8 @@
 use line_index::LineIndex;
 use log::info;
-use serde::Serialize;
+use rowan::TextRange;
+use serde::{Deserialize, Serialize};
+use squawk_syntax::ast::AstNode;
 use wasm_bindgen::prelude::*;
 use web_sys::js_sys::Error;
 
@@ -456,6 +458,59 @@ pub fn inlay_hints(content: String) -> Result<JsValue, Error> {
     serde_wasm_bindgen::to_value(&converted).map_err(into_error)
 }
 
+#[derive(Deserialize)]
+struct Position {
+    line: u32,
+    column: u32,
+}
+
+#[wasm_bindgen]
+pub fn selection_ranges(content: String, positions: Vec<JsValue>) -> Result<JsValue, Error> {
+    let parse = squawk_syntax::SourceFile::parse(&content);
+    let line_index = LineIndex::new(&content);
+    let tree = parse.tree();
+    let root = tree.syntax();
+
+    let mut results: Vec<Vec<WasmSelectionRange>> = vec![];
+
+    for pos in positions {
+        let pos: Position = serde_wasm_bindgen::from_value(pos).map_err(into_error)?;
+        let offset = position_to_offset(&line_index, pos.line, pos.column)?;
+
+        let mut ranges = vec![];
+        let mut range = TextRange::new(offset, offset);
+
+        for _ in 0..20 {
+            let next = squawk_ide::expand_selection::extend_selection(root, range);
+            if next == range {
+                break;
+            }
+
+            let start = line_index.line_col(next.start());
+            let end = line_index.line_col(next.end());
+            let start_wide = line_index
+                .to_wide(line_index::WideEncoding::Utf16, start)
+                .unwrap();
+            let end_wide = line_index
+                .to_wide(line_index::WideEncoding::Utf16, end)
+                .unwrap();
+
+            ranges.push(WasmSelectionRange {
+                start_line: start_wide.line,
+                start_column: start_wide.col,
+                end_line: end_wide.line,
+                end_column: end_wide.col,
+            });
+
+            range = next;
+        }
+
+        results.push(ranges);
+    }
+
+    serde_wasm_bindgen::to_value(&results).map_err(into_error)
+}
+
 #[derive(Serialize)]
 struct WasmInlayHint {
     line: u32,
@@ -463,3 +518,11 @@ struct WasmInlayHint {
     label: String,
     kind: String,
 }
+
+#[derive(Serialize)]
+struct WasmSelectionRange {
+    start_line: u32,
+    start_column: u32,
+    end_line: u32,
+    end_column: u32,
+}
diff --git a/playground/src/App.tsx b/playground/src/App.tsx
index 98dac012..ef0448fd 100644
--- a/playground/src/App.tsx
+++ b/playground/src/App.tsx
@@ -19,6 +19,7 @@ import {
   provideDefinition,
   provideReferences,
   provideDocumentSymbols,
+  provideSelectionRanges,
 } from "./providers"
 
 const modes = ["Lint", "Syntax Tree", "Tokens"] as const
@@ -410,6 +411,12 @@ function registerMonacoProviders() {
       provideInlayHints,
     },
   )
+
+  const selectionRangeProvider =
+    monaco.languages.registerSelectionRangeProvider("pgsql", {
+      provideSelectionRanges,
+    })
+
   return () => {
     languageConfig.dispose()
     codeActionProvider.dispose()
@@ -418,6 +425,7 @@ function registerMonacoProviders() {
     referencesProvider.dispose()
     documentSymbolProvider.dispose()
     inlayHintsProvider.dispose()
+    selectionRangeProvider.dispose()
     tokenProvider.dispose()
   }
 }
diff --git a/playground/src/providers.tsx b/playground/src/providers.tsx
index 020e927a..fc6dbcc1 100644
--- a/playground/src/providers.tsx
+++ b/playground/src/providers.tsx
@@ -6,6 +6,7 @@ import {
   goto_definition,
   hover,
   inlay_hints,
+  selection_ranges,
   DocumentSymbol,
 } from "./squawk"
 
@@ -211,3 +212,34 @@ export async function provideReferences(
     return []
   }
 }
+
+export async function provideSelectionRanges(
+  model: monaco.editor.ITextModel,
+  positions: monaco.Position[],
+): Promise<monaco.languages.SelectionRange[][]> {
+  const content = model.getValue()
+  if (!content) return []
+
+  try {
+    const wasmPositions = positions.map((pos) => ({
+      line: pos.lineNumber - 1,
+      column: pos.column - 1,
+    }))
+
+    const results = selection_ranges(content, wasmPositions)
+
+    return results.map((ranges) =>
+      ranges.map((range) => ({
+        range: {
+          startLineNumber: range.start_line + 1,
+          startColumn: range.start_column + 1,
+          endLineNumber: range.end_line + 1,
+          endColumn: range.end_column + 1,
+        },
+      })),
+    )
+  } catch (e) {
+    console.error("Error in provideSelectionRanges:", e)
+    return []
+  }
+}
diff --git a/playground/src/squawk.tsx b/playground/src/squawk.tsx
index 3b1bb357..e906c4ee 100644
--- a/playground/src/squawk.tsx
+++ b/playground/src/squawk.tsx
@@ -9,6 +9,7 @@ import initWasm, {
   document_symbols as document_symbols_,
   code_actions as code_actions_,
   inlay_hints as inlay_hints_,
+  selection_ranges as selection_ranges_,
 } from "./pkg/squawk_wasm"
 
 export type TextEdit = {
@@ -82,6 +83,13 @@ export function find_references(
   return find_references_(content, line, column)
 }
 
+export function selection_ranges(
+  content: string,
+  positions: Array<{ line: number; column: number }>,
+): SelectionRange[][] {
+  return selection_ranges_(content, positions)
+}
+
 export function useErrors(text: string) {
   const isReady = useWasmStatus()
   return isReady ? lint(text) : []
@@ -164,3 +172,10 @@ interface InlayHint {
   label: string
   kind: string
 }
+
+export interface SelectionRange {
+  start_line: number
+  start_column: number
+  end_line: number
+  end_column: number
+}