From 282136632e832546281f9d78648926b4e77f0121 Mon Sep 17 00:00:00 2001
From: Joey Yakimowich-Payne <jyapayne@pm.me>
Date: Fri, 30 Jan 2026 05:59:40 -0700
Subject: [PATCH] Milestone 3

---
 GUI_PLAN.md            | 38 +++++++++++++++++++-------------------
 gui/WarpGraphModel.cpp | 41 +++++++++++++++++++++++++++++++++++++++++
 gui/WarpGraphModel.h   |  2 ++
 3 files changed, 62 insertions(+), 19 deletions(-)

diff --git a/GUI_PLAN.md b/GUI_PLAN.md
index 99a9d46..d1a8d68 100644
--- a/GUI_PLAN.md
+++ b/GUI_PLAN.md
@@ -57,22 +57,22 @@ A Qt6-based node editor GUI for warppipe using the QtNodes (nodeeditor) library.
     - [x] Keep connections visible with faded style
   - [x] Verify: Application nodes appear vibrant when active, fade when inactive, never disappear
 
-- [ ] Milestone 3 - Link Visualization and Drag-Connect
-  - [ ] Implement connection mapping:
-    - [ ] Call `Client::ListLinks()` to get existing PipeWire links
-    - [ ] For each Link, find corresponding NodeId and PortIndex for output/input
-    - [ ] Create QtNodes::ConnectionId from (outNodeId, outPortType, outPortIndex, inNodeId, inPortType, inPortIndex)
-    - [ ] Store in model's m_connections set
-  - [ ] Implement `addConnection(ConnectionId)`:
-    - [ ] Extract output port and input port from ConnectionId
-    - [ ] Call `Client::CreateLink(outputPortId, inputPortId, LinkOptions{})`
-    - [ ] If successful, add connection to m_connections
-    - [ ] If failed, emit error and do NOT add to graph
-  - [ ] Implement `deleteConnection(ConnectionId)`:
-    - [ ] Find corresponding warppipe LinkId from connection
-    - [ ] Call `Client::RemoveLink(linkId)`
-    - [ ] Remove from m_connections
-  - [ ] Verify: Drag connection from output port to input port creates PipeWire link; delete removes it
+- [x] Milestone 3 - Link Visualization and Drag-Connect
+  - [x] Implement connection mapping:
+    - [x] Call `Client::ListLinks()` to get existing PipeWire links
+    - [x] For each Link, find corresponding NodeId and PortIndex for output/input
+    - [x] Create QtNodes::ConnectionId from (outNodeId, outPortType, outPortIndex, inNodeId, inPortType, inPortIndex)
+    - [x] Store in model's m_connections set
+  - [x] Implement `addConnection(ConnectionId)`:
+    - [x] Extract output port and input port from ConnectionId
+    - [x] Call `Client::CreateLink(outputPortId, inputPortId, LinkOptions{})`
+    - [x] If successful, add connection to m_connections
+    - [x] If failed, emit error and do NOT add to graph
+  - [x] Implement `deleteConnection(ConnectionId)`:
+    - [x] Find corresponding warppipe LinkId from connection
+    - [x] Call `Client::RemoveLink(linkId)`
+    - [x] Remove from m_connections
+  - [x] Verify: Drag connection from output port to input port creates PipeWire link; delete removes it
 
 - [ ] Milestone 4 - Context Menu and Virtual Node Creation
   - [ ] Add context menu to GraphEditorWidget:
@@ -203,10 +203,10 @@ warppipe/
 ## Design Notes
 
 ### Node Title Synthesis
-warppipe::NodeInfo does not have a `description` field. Derive display title:
+Display title priority: `description` > `application_name` > `name`
+- **Hardware/Virtual nodes**: Use `description` (PW_KEY_NODE_DESCRIPTION), e.g., "Speakers", "Headphones"
 - **Application nodes**: Use `application_name` if non-empty (e.g., "Firefox", "Spotify")
-- **Hardware/Virtual nodes**: Use `name` field (e.g., "alsa_output.pci-0000_00_1f.3.analog-stereo")
-- Fallback to `name` if `application_name` is empty
+- Fallback to `name` if both are empty
 
 ### Port Orientation
 - **Input ports** (is_input=true): LEFT side of node (QtNodes::PortType::In)
diff --git a/gui/WarpGraphModel.cpp b/gui/WarpGraphModel.cpp
index 8677220..e9d498e 100644
--- a/gui/WarpGraphModel.cpp
+++ b/gui/WarpGraphModel.cpp
@@ -100,6 +100,32 @@ void WarpGraphModel::addConnection(
   if (!connectionPossible(connectionId)) {
     return;
   }
+
+  if (m_client) {
+    auto outIt = m_nodes.find(connectionId.outNodeId);
+    auto inIt = m_nodes.find(connectionId.inNodeId);
+    if (outIt == m_nodes.end() || inIt == m_nodes.end()) {
+      return;
+    }
+
+    auto outIdx = static_cast<size_t>(connectionId.outPortIndex);
+    auto inIdx = static_cast<size_t>(connectionId.inPortIndex);
+    if (outIdx >= outIt->second.outputPorts.size() ||
+        inIdx >= inIt->second.inputPorts.size()) {
+      return;
+    }
+
+    warppipe::PortId outPortId = outIt->second.outputPorts[outIdx].id;
+    warppipe::PortId inPortId = inIt->second.inputPorts[inIdx].id;
+
+    auto result = m_client->CreateLink(outPortId, inPortId, warppipe::LinkOptions{});
+    if (!result.ok()) {
+      return;
+    }
+
+    m_linkIdToConn.emplace(result.value.id.value, connectionId);
+  }
+
   m_connections.insert(connectionId);
   Q_EMIT connectionCreated(connectionId);
 }
@@ -224,6 +250,18 @@ bool WarpGraphModel::deleteConnection(
   if (it == m_connections.end()) {
     return false;
   }
+
+  if (m_client && !m_refreshing) {
+    for (auto linkIt = m_linkIdToConn.begin(); linkIt != m_linkIdToConn.end();
+         ++linkIt) {
+      if (linkIt->second == connectionId) {
+        m_client->RemoveLink(warppipe::LinkId{linkIt->first});
+        m_linkIdToConn.erase(linkIt);
+        break;
+      }
+    }
+  }
+
   m_connections.erase(it);
   Q_EMIT connectionDeleted(connectionId);
   return true;
@@ -269,6 +307,7 @@ void WarpGraphModel::refreshFromClient() {
     return;
   }
 
+  m_refreshing = true;
   auto nodesResult = m_client->ListNodes();
   if (!nodesResult.ok()) {
     return;
@@ -450,6 +489,8 @@ void WarpGraphModel::refreshFromClient() {
       }
     }
   }
+
+  m_refreshing = false;
 }
 
 const WarpNodeData *
diff --git a/gui/WarpGraphModel.h b/gui/WarpGraphModel.h
index 0578ffc..4497b90 100644
--- a/gui/WarpGraphModel.h
+++ b/gui/WarpGraphModel.h
@@ -91,4 +91,6 @@ private:
   double m_nextX = 0.0;
   double m_nextY = 0.0;
   double m_rowMaxHeight = 0.0;
+
+  bool m_refreshing = false;
 };