Add initial project.

src/view/graph_view.rs

@@ -0,0 +1,96 @@
+use super::PipewireNode;
+use cairo::Context;
+use glib::clone;
+use gtk::{prelude::*, LayoutExt};
+use std::{cell::RefCell, collections::HashMap, rc::Rc};
+
+pub struct GraphView {
+    pub(crate) widget: gtk::Layout,
+    nodes: Rc<RefCell<HashMap<u32, PipewireNode>>>,
+    links: Rc<RefCell<HashMap<u32, crate::PipewireLink>>>,
+}
+
+impl GraphView {
+    pub fn new() -> Self {
+        let result = Self {
+            widget: gtk::Layout::new::<gtk::Adjustment, gtk::Adjustment>(None, None),
+            nodes: Rc::new(RefCell::new(HashMap::new())),
+            links: Rc::new(RefCell::new(HashMap::new())),
+        };
+
+        result.widget.connect_draw(clone!(
+        @weak result.nodes as nodes, @weak result.links as links => @default-panic,
+        move |_, cr| {
+            draw(nodes, links, cr);
+            Inhibit(false)
+        }));
+
+        result
+    }
+
+    pub fn add_node(&mut self, id: u32, node: PipewireNode) {
+        // TODO: Find a free position to put the widget at.
+        self.widget.put(
+            &node.widget,
+            (self.nodes.borrow().len() % 4 * 400) as i32,
+            (self.nodes.borrow().len() / 4 * 100) as i32,
+        );
+        self.nodes.borrow_mut().insert(id, node);
+    }
+
+    /// Add a link to the graph.
+    ///
+    /// `add_link` takes three arguments: `link_id` is the id of the link as assigned by the pipewire server,
+    /// `from` and `to` are the id's of the ingoing and outgoing port, respectively.
+    pub fn add_link(&mut self, link_id: u32, link: crate::PipewireLink) {
+        self.links.borrow_mut().insert(link_id, link);
+        self.widget.queue_draw();
+    }
+}
+
+fn draw(
+    nodes: Rc<RefCell<HashMap<u32, PipewireNode>>>,
+    links: Rc<RefCell<HashMap<u32, crate::PipewireLink>>>,
+    cr: &Context,
+) {
+    cr.set_line_width(2.0);
+    cr.set_source_rgb(255.0, 255.0, 255.0);
+    cr.paint();
+    cr.set_source_rgb(0.0, 0.0, 0.0);
+    for link in links.borrow().values() {
+        let (from_alloc, to_alloc) = get_allocs(nodes.clone(), link);
+
+        cr.move_to(
+            (from_alloc.x + from_alloc.width).into(),
+            (from_alloc.y + (from_alloc.height / 2)).into()
+        );
+        cr.line_to(
+            to_alloc.x.into(),
+            (to_alloc.y + (to_alloc.height / 2)).into()
+        );
+
+        cr.stroke();
+    }
+}
+
+fn get_allocs(
+    nodes: Rc<RefCell<HashMap<u32, PipewireNode>>>,
+    link: &crate::PipewireLink,
+) -> (gtk::Allocation, gtk::Allocation) {
+    let from_alloc = &nodes
+        .borrow()
+        .get(&link.node_from)
+        .unwrap()
+        .get_outgoing_port(link.port_from)
+        .unwrap()
+        .get_allocation();
+    let to_alloc = &nodes
+        .borrow()
+        .get(&link.node_to)
+        .unwrap()
+        .get_ingoing_port(link.port_to)
+        .unwrap()
+        .get_allocation();
+
+    (from_alloc.to_owned(), to_alloc.to_owned())
+}