split the selection panel into one card per kind of selection

src/ui/selection/MultiBuildingContent.cpp

@@ -0,0 +1,90 @@
+#include "MultiBuildingContent.h"
+
+#include <map>
+
+#include <QLabel>
+#include <QStringList>
+#include <QVBoxLayout>
+
+#include "Building.h"
+#include "ClearBeltControl.h"
+#include "FactoryQueries.h"
+#include "GameConfig.h"
+#include "SelectionNames.h"
+#include "Simulation.h"
+
+MultiBuildingContent::MultiBuildingContent(const SelectionContext& context,
+                                           const SelectionRequest& request,
+                                           QWidget* parent)
+    : SelectionContent(context, std::nullopt, parent)
+    , m_ids(request.buildings)
+{
+    m_countsLabel    = new QLabel(this);
+    m_totalCostLabel = new QLabel(this);
+    getRuntimeLayout()->addWidget(m_countsLabel);
+    getRuntimeLayout()->addWidget(m_totalCostLabel);
+
+    // A selection holding any belt-subsystem tile can still be cleared as a whole
+    // (REQ-UI-BELT-CLEAR), even though the mixture is what kept it from aggregating.
+    bool hasBeltTile = false;
+    for (BuildingId id : m_ids)
+    {
+        const Building* building = findBuilding(context.sim->getFactoryState(), id);
+        if (building && isBeltSubsystemType(building->type))
+        {
+            hasBeltTile = true;
+            break;
+        }
+    }
+    if (hasBeltTile)
+    {
+        getRuntimeLayout()->addWidget(new ClearBeltControl(context, m_ids, this));
+    }
+
+    // The header names the size of the selection instead of an object
+    // (REQ-UI-MULTI-SELECTION).
+    setIdentity(QPixmap(), tr("%1 buildings").arg(static_cast<int>(m_ids.size())));
+
+    buildSummary();
+}
+
+void MultiBuildingContent::buildSummary()
+{
+    std::map<BuildingType, int> counts;
+    for (BuildingId id : m_ids)
+    {
+        const Building* building =
+            findBuilding(getContext().sim->getFactoryState(), id);
+        if (building)
+        {
+            counts[building->type]++;
+            continue;
+        }
+        const ConstructionSite* site =
+            findSite(getContext().sim->getFactoryState(), id);
+        if (site)
+        {
+            counts[site->type]++;
+        }
+    }
+
+    QStringList lines;
+    int totalCost = 0;
+    for (const std::pair<const BuildingType, int>& entry : counts)
+    {
+        lines << tr("%1 x %2").arg(getBuildingTypeName(entry.first)).arg(entry.second);
+
+        // Only player-placeable buildings count toward the total; the HQ and defence
+        // stations are excluded (REQ-UI-MULTI-SELECTION). A construction site counts at
+        // its type's full placement cost regardless of progress.
+        const BuildingDef* def =
+            getContext().config->buildings.findBuildingDef(entry.first);
+        if (def && def->playerPlaceable)
+        {
+            totalCost += def->cost * entry.second;
+        }
+    }
+
+    m_countsLabel->setText(lines.join('\n'));
+    m_totalCostLabel->setText(tr("Total: %1 Building Blocks").arg(totalCost));
+}