From 85399c12c266a36fdf0777254a3c39c85c4d3877 Mon Sep 17 00:00:00 2001
From: Michael Gregorius <michael.gregorius.git@arcor.de>
Date: Sat, 13 Jan 2024 22:03:03 +0100
Subject: [PATCH] Abstraction in MixerChannelView (#7057)

Reduce code repetition in `MixerChannelView` by introducing methods that:
* Retrieve the `MixerChannel` that's associated with the view
* Check if the associated channel is the master channel

This abstracts some functionality and also reduces direct usage of the variable `m_channelIndex`.
---
 include/MixerChannelView.h   |  7 +++++++
 src/gui/MixerChannelView.cpp | 29 +++++++++++++++++------------
 2 files changed, 24 insertions(+), 12 deletions(-)

diff --git a/include/MixerChannelView.h b/include/MixerChannelView.h
index 8d2306f91..1710623d7 100644
--- a/include/MixerChannelView.h
+++ b/include/MixerChannelView.h
@@ -38,6 +38,11 @@
 #include <QPixmap>
 #include <QWidget>
 
+namespace lmms
+{
+    class MixerChannel;
+}
+
 namespace lmms::gui
 {
     constexpr int MIXER_CHANNEL_INNER_BORDER_SIZE = 3;
@@ -100,6 +105,8 @@ namespace lmms::gui
 
     private:
         QString elideName(const QString& name);
+        MixerChannel* mixerChannel() const;
+        auto isMasterChannel() const -> bool { return m_channelIndex == 0; }
 
     private:
         SendButtonIndicator* m_sendButton;
diff --git a/src/gui/MixerChannelView.cpp b/src/gui/MixerChannelView.cpp
index 0f8ccedea..9ea266238 100644
--- a/src/gui/MixerChannelView.cpp
+++ b/src/gui/MixerChannelView.cpp
@@ -144,9 +144,9 @@ namespace lmms::gui
 
     void MixerChannelView::contextMenuEvent(QContextMenuEvent*)
     {
-        auto contextMenu = new CaptionMenu(Engine::mixer()->mixerChannel(m_channelIndex)->m_name, this);
+        auto contextMenu = new CaptionMenu(mixerChannel()->m_name, this);
 
-        if (m_channelIndex != 0) // no move-options in master
+        if (!isMasterChannel()) // no move-options in master
         {
             contextMenu->addAction(tr("Move &left"), this, &MixerChannelView::moveChannelLeft);
             contextMenu->addAction(tr("Move &right"), this, &MixerChannelView::moveChannelRight);
@@ -155,7 +155,7 @@ namespace lmms::gui
         contextMenu->addAction(tr("Rename &channel"), this, &MixerChannelView::renameChannel);
         contextMenu->addSeparator();
 
-        if (m_channelIndex != 0) // no remove-option in master
+        if (!isMasterChannel()) // no remove-option in master
         {
             contextMenu->addAction(embed::getIconPixmap("cancel"), tr("R&emove channel"), this, &MixerChannelView::removeChannel);
             contextMenu->addSeparator();
@@ -178,7 +178,7 @@ namespace lmms::gui
     void MixerChannelView::paintEvent(QPaintEvent* event)
     {
         auto * mixer = Engine::mixer();
-        const auto channel = mixer->mixerChannel(m_channelIndex);
+        const auto channel = mixerChannel();
         const bool muted = channel->m_muteModel.value();
         const auto name = channel->m_name;
         const auto elidedName = elideName(name);
@@ -351,7 +351,7 @@ namespace lmms::gui
 
         m_channelNumberLcd->hide();
         m_renameLineEdit->setFixedWidth(m_renameLineEdit->width());
-        m_renameLineEdit->setText(Engine::mixer()->mixerChannel(m_channelIndex)->m_name);
+        m_renameLineEdit->setText(mixerChannel()->m_name);
 
         m_renameLineEditView->setFocus();
         m_renameLineEdit->selectAll();
@@ -370,27 +370,27 @@ namespace lmms::gui
         auto newName = m_renameLineEdit->text();
         setFocus();
 
-        const auto mixerChannel = Engine::mixer()->mixerChannel(m_channelIndex);
-        if (!newName.isEmpty() && mixerChannel->m_name != newName)
+        const auto mc = mixerChannel();
+        if (!newName.isEmpty() && mc->m_name != newName)
         {
-            mixerChannel->m_name = newName;
+            mc->m_name = newName;
             m_renameLineEdit->setText(elideName(newName));
             Engine::getSong()->setModified();
         }
 
-        setToolTip(mixerChannel->m_name);
+        setToolTip(mc->m_name);
     }
 
     void MixerChannelView::resetColor()
     {
-        Engine::mixer()->mixerChannel(m_channelIndex)->setColor(std::nullopt);
+        mixerChannel()->setColor(std::nullopt);
         Engine::getSong()->setModified();
         update();
     }
 
     void MixerChannelView::selectColor()
     {
-        const auto channel = Engine::mixer()->mixerChannel(m_channelIndex);
+        const auto channel = mixerChannel();
 
         const auto initialColor = channel->color().value_or(backgroundActive().color());
         const auto * colorChooser = ColorChooser{this}.withPalette(ColorChooser::Palette::Mixer);
@@ -406,7 +406,7 @@ namespace lmms::gui
 
     void MixerChannelView::randomizeColor()
     {
-        auto channel = Engine::mixer()->mixerChannel(m_channelIndex);
+        auto channel = mixerChannel();
         channel->setColor(ColorChooser::getPalette(ColorChooser::Palette::Mixer)[rand() % 48]);
         Engine::getSong()->setModified();
         update();
@@ -444,4 +444,9 @@ namespace lmms::gui
         return elidedName;
     }
 
+    MixerChannel* MixerChannelView::mixerChannel() const
+    {
+        return Engine::mixer()->mixerChannel(m_channelIndex);
+    }
+
 } // namespace lmms::gui
\ No newline at end of file