split the selection panel into one card per kind of selection

src/ui/selection/BufferSection.cpp

@@ -0,0 +1,95 @@
+#include "BufferSection.h"
+
+#include <QLabel>
+#include <QVBoxLayout>
+
+#include "Building.h"
+
+namespace
+{
+
+// One "<item>: <count>[/<per cycle>]" entry.
+QString formatEntry(const std::string& itemId, int count, int perCycle)
+{
+    QString text = QString::fromStdString(itemId) + ": " + QString::number(count);
+    if (perCycle > 0)
+    {
+        text += "/" + QString::number(perCycle);
+    }
+    return text + "  ";
+}
+
+int findPerCycle(const std::map<std::string, int>& perCycle, const std::string& itemId)
+{
+    const std::map<std::string, int>::const_iterator it = perCycle.find(itemId);
+    return (it != perCycle.end()) ? it->second : 0;
+}
+
+}  // namespace
+
+
+BufferSection::BufferSection(QWidget* parent)
+    : QWidget(parent)
+{
+    QVBoxLayout* layout = new QVBoxLayout(this);
+    layout->setContentsMargins(0, 0, 0, 0);
+    layout->setSpacing(0);
+
+    m_label = new QLabel(this);
+    m_label->setWordWrap(true);
+    layout->addWidget(m_label);
+}
+
+void BufferSection::setBuffers(const Building& building,
+                               const std::map<std::string, int>& perCycleInputs,
+                               const std::map<std::string, int>& perCycleOutputs)
+{
+    QString text;
+
+    if (!building.inputBuffer.counts.empty())
+    {
+        text += tr("Input: ");
+        for (const std::pair<const ItemType, int>& entry : building.inputBuffer.counts)
+        {
+            text += formatEntry(entry.first.id, entry.second,
+                                findPerCycle(perCycleInputs, entry.first.id));
+        }
+        text += "\n";
+    }
+
+    // Output-side items are the buffered ones plus those still emerging onto the output
+    // belts: an emerging item still belongs to the output buffer (REQ-MAT-OUTPUT-EMERGE),
+    // so leaving it out would make it vanish from the panel while it animates.
+    std::map<std::string, int> outputCounts;
+    for (const Item& item : building.outputBuffer.items)
+    {
+        outputCounts[item.type.id]++;
+    }
+    for (const std::vector<BeltItemSlot>& lane : building.emergingItems)
+    {
+        for (const BeltItemSlot& slot : lane)
+        {
+            outputCounts[slot.item.type.id]++;
+        }
+    }
+
+    // A configured building lists every item its cycle produces, so an output the player
+    // is waiting for shows as 0 rather than being absent.
+    for (const std::pair<const std::string, int>& entry : perCycleOutputs)
+    {
+        outputCounts.emplace(entry.first, 0);
+    }
+
+    if (!outputCounts.empty())
+    {
+        text += tr("Output: ");
+        for (const std::pair<const std::string, int>& entry : outputCounts)
+        {
+            text += formatEntry(entry.first, entry.second,
+                                findPerCycle(perCycleOutputs, entry.first));
+        }
+    }
+
+    m_label->setText(text.trimmed());
+    setVisible(!text.trimmed().isEmpty());
+}