From 47db70a12e71ba59aff3abcc153d5b9b8108100a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jan=20K=C3=A4berich?= <j.kaeberich@gmx.de>
Date: Wed, 23 Apr 2025 15:40:04 +0200
Subject: [PATCH] Preselect most likely matching traces in touchstone export
 dialog

---
 .../CustomWidgets/tracesetselector.h          |  1 +
 .../Traces/tracetouchstoneexport.cpp          | 44 ++++++++++++++++---
 .../Traces/tracetouchstoneexport.h            |  3 +-
 .../LibreVNA-GUI/VNA/tracewidgetvna.cpp       | 10 -----
 4 files changed, 39 insertions(+), 19 deletions(-)

diff --git a/Software/PC_Application/LibreVNA-GUI/CustomWidgets/tracesetselector.h b/Software/PC_Application/LibreVNA-GUI/CustomWidgets/tracesetselector.h
index 33a4b3a..1382d1d 100644
--- a/Software/PC_Application/LibreVNA-GUI/CustomWidgets/tracesetselector.h
+++ b/Software/PC_Application/LibreVNA-GUI/CustomWidgets/tracesetselector.h
@@ -35,6 +35,7 @@ public:
     double getLowerFreq() const;
     double getUpperFreq() const;
     double getReferenceImpedance() const;
+    TraceModel* getModel() const {return model;}
 
 signals:
     void selectionChanged();
diff --git a/Software/PC_Application/LibreVNA-GUI/Traces/tracetouchstoneexport.cpp b/Software/PC_Application/LibreVNA-GUI/Traces/tracetouchstoneexport.cpp
index 3e604bb..f091c22 100644
--- a/Software/PC_Application/LibreVNA-GUI/Traces/tracetouchstoneexport.cpp
+++ b/Software/PC_Application/LibreVNA-GUI/Traces/tracetouchstoneexport.cpp
@@ -17,7 +17,23 @@ TraceTouchstoneExport::TraceTouchstoneExport(TraceModel &model, QWidget *parent)
     ui->selector->setModel(&model);
     ui->selector->setPartialSelectionAllowed(true);
     connect(ui->selector, qOverload<>(&TraceSetSelector::selectionChanged), this, &TraceTouchstoneExport::selectionChanged);
-    on_sbPorts_valueChanged(ui->sbPorts->value());
+    connect(ui->sbPorts, &QSpinBox::valueChanged, this, &TraceTouchstoneExport::setPortNum);
+    // figure out how many ports the user most likely needs
+    unsigned int p;
+    for(p=4;p>=1;p--) {
+        // do we have a trace name which could indicate such a number of ports?
+        for(unsigned int i=1;i<=p;i++) {
+            auto n1 = "S"+QString::number(p)+QString::number(i);
+            auto n2 = "S"+QString::number(i)+QString::number(p);
+            for(auto t : model.getTraces()) {
+                if(t->name().contains(n1) || t->name().contains(n2)) {
+                    goto traceFound;
+                }
+            }
+        }
+    }
+traceFound:
+    setPortNum(p);
 }
 
 TraceTouchstoneExport::~TraceTouchstoneExport()
@@ -30,13 +46,32 @@ bool TraceTouchstoneExport::setTrace(int portFrom, int portTo, Trace *t)
     return ui->selector->setTrace(portTo, portFrom, t);
 }
 
-bool TraceTouchstoneExport::setPortNum(int ports)
+bool TraceTouchstoneExport::setPortNum(unsigned int ports)
 {
     if(ports < 1 || ports > 4) {
         return false;
     }
+    if((unsigned int) ui->sbPorts->value() == ports && ui->selector->getPorts() == ports) {
+        // already set correctly, nothing to do
+        return true;
+    }
     ui->sbPorts->setValue(ports);
     ui->selector->setPorts(ports);
+    // Attempt to set default traces (this will result in correctly populated
+    // 2 port export if the initial 4 traces have not been modified)
+    auto traces = ui->selector->getModel()->getTraces();
+    for(unsigned int i=1;i<=ports;i++) {
+        for(unsigned int j=1;j<=ports;j++) {
+            auto name = "S"+QString::number(i)+QString::number(j);
+            for(auto t : traces) {
+                if(t->name().contains(name)) {
+                    // this could be the correct trace
+                    setTrace(j, i, t);
+                    break;
+                }
+            }
+        }
+    }
     return true;
 }
 
@@ -86,11 +121,6 @@ void TraceTouchstoneExport::on_buttonBox_accepted()
     }
 }
 
-void TraceTouchstoneExport::on_sbPorts_valueChanged(int ports)
-{
-    ui->selector->setPorts(ports);
-}
-
 void TraceTouchstoneExport::selectionChanged()
 {
     auto valid = ui->selector->selectionValid();
diff --git a/Software/PC_Application/LibreVNA-GUI/Traces/tracetouchstoneexport.h b/Software/PC_Application/LibreVNA-GUI/Traces/tracetouchstoneexport.h
index ae27d7f..c984a39 100644
--- a/Software/PC_Application/LibreVNA-GUI/Traces/tracetouchstoneexport.h
+++ b/Software/PC_Application/LibreVNA-GUI/Traces/tracetouchstoneexport.h
@@ -19,11 +19,10 @@ public:
     explicit TraceTouchstoneExport(TraceModel &model, QWidget *parent = nullptr);
     ~TraceTouchstoneExport();
     bool setTrace(int portFrom, int portTo, Trace *t);
-    bool setPortNum(int ports);
+    bool setPortNum(unsigned int ports);
 
 private slots:
     void on_buttonBox_accepted();
-    void on_sbPorts_valueChanged(int ports);
     void selectionChanged();
 
 private:
diff --git a/Software/PC_Application/LibreVNA-GUI/VNA/tracewidgetvna.cpp b/Software/PC_Application/LibreVNA-GUI/VNA/tracewidgetvna.cpp
index 6327e5c..cfdf8f8 100644
--- a/Software/PC_Application/LibreVNA-GUI/VNA/tracewidgetvna.cpp
+++ b/Software/PC_Application/LibreVNA-GUI/VNA/tracewidgetvna.cpp
@@ -35,16 +35,6 @@ void TraceWidgetVNA::exportCSV()
 void TraceWidgetVNA::exportTouchstone()
 {
     auto e = new TraceTouchstoneExport(model);
-    // Attempt to set default traces (this will result in correctly populated
-    // 2 port export if the initial 4 traces have not been modified)
-    e->setPortNum(2);
-    auto traces = model.getTraces();
-    for(unsigned int i=0;i<4;i++) {
-        if(i >= traces.size()) {
-            break;
-        }
-        e->setTrace(i%2+1, i/2+1, traces[i]);
-    }
     if(AppWindow::showGUI()) {
         e->show();
     }