M0: desktop app: toolbar, browser, timeline, GPU viewport, view cube, sketch tools, dialogs, control channel

Co-Authored-By: Claude Opus 5.5 <[email protected]>

apps/solvecraft/src/control_server.rs

@@ -0,0 +1,62 @@
+//! Loopback JSON-lines control server: one request per line, one reply per line.
+//! Agents and tests drive the app through it (adapted from CADCraft, MIT OR Apache-2.0).
+
+use std::io::{BufRead, BufReader, Write};
+use std::net::{TcpListener, TcpStream};
+use std::sync::mpsc::{Receiver, Sender, channel};
+use std::time::Duration;
+
+use serde_json::{Value, json};
+use solvecraft_ui_egui::ControlRequest;
+
+pub fn start(port: u16, ctx: egui::Context) -> Receiver<ControlRequest> {
+    let (tx, rx) = channel::<ControlRequest>();
+    let listener = match TcpListener::bind(("127.0.0.1", port)) {
+        Ok(l) => l,
+        Err(e) => {
+            eprintln!("solvecraft: control server failed to bind 127.0.0.1:{port}: {e}");
+            return rx;
+        }
+    };
+    eprintln!("solvecraft: control server listening on 127.0.0.1:{port}");
+    std::thread::spawn(move || {
+        for stream in listener.incoming().flatten() {
+            let tx = tx.clone();
+            let ctx = ctx.clone();
+            std::thread::spawn(move || serve(stream, tx, ctx));
+        }
+    });
+    rx
+}
+
+fn serve(stream: TcpStream, tx: Sender<ControlRequest>, ctx: egui::Context) {
+    let Ok(read) = stream.try_clone() else { return };
+    let mut out = stream;
+    for line in BufReader::new(read).lines() {
+        let Ok(line) = line else { break };
+        if line.trim().is_empty() {
+            continue;
+        }
+        let reply = match serde_json::from_str::<Value>(&line) {
+            Ok(msg) => {
+                let id = msg.get("id").cloned().unwrap_or(Value::Null);
+                let method = msg.get("method").and_then(Value::as_str).unwrap_or("").to_string();
+                let params = msg.get("params").cloned().unwrap_or(json!({}));
+                let (req, rrx) = ControlRequest::new(method, params);
+                if tx.send(req).is_err() {
+                    break;
+                }
+                ctx.request_repaint();
+                let mut r = rrx.recv_timeout(Duration::from_secs(60)).unwrap_or_else(|_| json!({"ok": false, "error": "timeout"}));
+                if let Some(o) = r.as_object_mut() {
+                    o.insert("id".into(), id);
+                }
+                r
+            }
+            Err(e) => json!({"ok": false, "error": format!("bad JSON: {e}")}),
+        };
+        if writeln!(out, "{reply}").is_err() {
+            break;
+        }
+    }
+}