allow multi-select for ships/stations, mixable with scrap

src/ui/SelectedBuildingPanel.cpp

@@ -9,14 +9,16 @@
 #include <QLabel>
 #include <QListWidget>
 #include <QPushButton>
+#include <QStringList>
 #include <QVBoxLayout>
 
 #include "BeltSystem.h"
 #include "Command.h"
 #include "CommandRequestedEvent.h"
+#include "DisplayName.h"
 #include "DynamicBodyComponent.h"
 #include "EntityAdmin.h"
-#include "EntitySelectedEvent.h"
+#include "EntitySelectionChangedEvent.h"
 #include "EventManager.h"
 #include "FactionComponent.h"
 #include "HealthComponent.h"
@@ -196,6 +198,11 @@ SelectedBuildingPanel::SelectedBuildingPanel(Simulation* sim,
     m_layout->addWidget(m_stationStatsLabel);
     m_stationStatsLabel->hide();
 
+    m_entitySummaryLabel = new QLabel(this);
+    m_entitySummaryLabel->setWordWrap(true);
+    m_layout->addWidget(m_entitySummaryLabel);
+    m_entitySummaryLabel->hide();
+
     m_scrapLabel = new QLabel(this);
     m_layout->addWidget(m_scrapLabel);
     m_scrapLabel->hide();
@@ -215,8 +222,9 @@ void SelectedBuildingPanel::onSelectionChanged(const std::vector<BuildingId>& id
     m_selectedBuildingIds = ids;
     if (!ids.empty())
     {
+        // A building selection is exclusive: it supersedes any field selection —
+        // actors and scrap (REQ-UI-SELECTION-CATEGORIES).
         clearEntityDisplay();
-        // A building selection supersedes any scrap selection (REQ-UI-SCRAP-CLICK-SELECT).
         m_selectedScrap.clear();
         m_scrapLabel->hide();
     }
@@ -266,6 +274,7 @@ void SelectedBuildingPanel::buildEmpty()
     m_entityTitleLabel->hide();
     m_entityStatsPanel->hide();
     m_stationStatsLabel->hide();
+    m_entitySummaryLabel->hide();
 }
 
 void SelectedBuildingPanel::buildSingle(BuildingId id)
@@ -658,16 +667,24 @@ void SelectedBuildingPanel::handleEvent(
 
 void SelectedBuildingPanel::refreshSelectionDisplay(RefreshReason reason)
 {
-    if (!m_selectedScrap.empty())
+    if (!m_selectedEntities.empty() || !m_selectedScrap.empty())
     {
-        // The total shrinks live as piles are collected or despawn (REQ-UI-SCRAP-PANEL).
-        refreshScrapTotal();
-        return;
-    }
-
-    if (m_selectedEntity.has_value())
-    {
-        refreshEntityStats();
+        // Field selection. Keep the live values current: the single-actor stats panel,
+        // the standalone scrap total, or the count summary (whose scrap line shrinks as
+        // piles are collected) — matching the layout chosen by buildFieldSelection()
+        // (REQ-UI-SHIP-STATS-PANEL, REQ-UI-SCRAP-PANEL).
+        if (m_selectedEntities.size() == 1 && m_selectedScrap.empty())
+        {
+            refreshEntityStats();
+        }
+        else if (m_selectedEntities.empty())
+        {
+            refreshScrapTotal();
+        }
+        else
+        {
+            buildEntitySummary();
+        }
         return;
     }
 
@@ -737,7 +754,7 @@ void SelectedBuildingPanel::buildMulti(const std::vector<BuildingId>& ids)
     QString text;
     for (const std::pair<const BuildingType, int>& entry : counts)
     {
-        text += buildingTypeName(entry.first) + ": "
+        text += buildingTypeName(entry.first) + " x "
             + QString::number(entry.second) + "\n";
         if (isBeltLike(entry.first))
         {
@@ -906,39 +923,139 @@ void SelectedBuildingPanel::onClearBelt()
     }
 }
 
-void SelectedBuildingPanel::handleEvent(std::shared_ptr<const EntitySelectedEvent> event)
+void SelectedBuildingPanel::handleEvent(std::shared_ptr<const EntitySelectionChangedEvent> event)
 {
-    if (event->entity.has_value())
+    m_selectedEntities = event->entities;
+    if (!m_selectedEntities.empty())
     {
-        m_selectedEntity = event->entity;
+        // A field selection supersedes any building selection (REQ-UI-SELECTION-CATEGORIES).
         m_selectedBuildingIds.clear();
-        // An entity selection supersedes any scrap selection (REQ-UI-SCRAP-CLICK-SELECT).
-        m_selectedScrap.clear();
+    }
+    buildFieldSelection();
+}
+
+void SelectedBuildingPanel::buildFieldSelection()
+{
+    if (m_selectedEntities.empty() && m_selectedScrap.empty())
+    {
+        // Nothing in the field category. Fall back to empty unless buildings own the panel.
+        clearEntityDisplay();
         m_scrapLabel->hide();
-        clearContent();
-
-        EntityAdmin& admin = m_sim->getAdmin();
-        entt::entity entity = *m_selectedEntity;
-
-        if (!admin.isValid(entity))
+        if (m_selectedBuildingIds.empty())
         {
-            clearEntityDisplay();
-            return;
+            buildEmpty();
         }
+        return;
+    }
 
-        if (admin.hasAll<ShipIdentityComponent>(entity))
+    // A field selection owns the panel: drop any building content.
+    clearContent();
+
+    EntityAdmin& admin = m_sim->getAdmin();
+
+    // Full single-actor stats are shown only for a lone actor with no scrap. As soon as
+    // the selection holds more than one object (multiple actors, or an actor plus scrap),
+    // the panel switches to the compact count summary (REQ-UI-FIELD-MULTI-SELECTION).
+    if (m_selectedEntities.size() == 1 && m_selectedScrap.empty())
+    {
+        m_entitySummaryLabel->hide();
+        m_scrapLabel->hide();
+        const entt::entity entity = m_selectedEntities.front();
+        if (admin.isValid(entity) && admin.hasAll<ShipIdentityComponent>(entity))
         {
             buildEntityShip(entity);
         }
-        else if (admin.hasAll<StationBodyComponent>(entity))
+        else if (admin.isValid(entity) && admin.hasAll<StationBodyComponent>(entity))
         {
             buildEntityStation(entity);
         }
+        else
+        {
+            m_entityTitleLabel->hide();
+            m_entityStatsPanel->hide();
+            m_stationStatsLabel->hide();
+        }
+        return;
     }
-    else
+
+    m_entityTitleLabel->hide();
+    m_entityStatsPanel->hide();
+    m_stationStatsLabel->hide();
+
+    if (m_selectedEntities.empty())
     {
-        clearEntityDisplay();
+        // Scrap only: a single "Scrap: N" line.
+        m_entitySummaryLabel->hide();
+        refreshScrapTotal();
+        m_scrapLabel->show();
+        return;
     }
+
+    // Actor counts, with the scrap total appended into the same label so every line
+    // shares the same spacing.
+    m_scrapLabel->hide();
+    buildEntitySummary();
+}
+
+void SelectedBuildingPanel::buildEntitySummary()
+{
+    EntityAdmin& admin = m_sim->getAdmin();
+
+    // Group actors by faction + kind + ship schematic, preserving first-seen order
+    // (REQ-UI-FIELD-MULTI-SELECTION).
+    std::vector<QString> keys;
+    std::map<QString, int> counts;
+    std::map<QString, QString> labels;
+
+    for (entt::entity entity : m_selectedEntities)
+    {
+        if (!admin.isValid(entity)) { continue; }
+        const bool isEnemy = admin.hasAll<FactionComponent>(entity)
+            && admin.get<FactionComponent>(entity).isEnemy;
+
+        QString key;
+        QString label;
+        if (admin.hasAll<ShipIdentityComponent>(entity))
+        {
+            const std::string& id = admin.get<ShipIdentityComponent>(entity).schematicId;
+            const QString name = QString::fromStdString(toDisplayName(id));
+            key = (isEnemy ? QStringLiteral("ship:enemy:") : QStringLiteral("ship:player:"))
+                + QString::fromStdString(id);
+            label = isEnemy ? tr("Enemy %1").arg(name) : name;
+        }
+        else if (admin.hasAll<StationBodyComponent>(entity))
+        {
+            key = isEnemy ? QStringLiteral("station:enemy") : QStringLiteral("station:player");
+            label = isEnemy ? tr("Enemy Defence Station") : tr("Player Defence Station");
+        }
+        else
+        {
+            continue;
+        }
+
+        if (counts.find(key) == counts.end())
+        {
+            keys.push_back(key);
+            labels[key] = label;
+        }
+        counts[key] += 1;
+    }
+
+    // One "<type> x <count>" line per group (matching the recipe tooltip and the building
+    // multi-selection). No total-count header, consistent with the building panel. The
+    // scrap total, when present, is appended as another line in the same label so the
+    // line spacing is uniform (REQ-UI-FIELD-MULTI-SELECTION, REQ-UI-SCRAP-PANEL).
+    QStringList lines;
+    for (const QString& key : keys)
+    {
+        lines << tr("%1 x %2").arg(labels[key]).arg(counts[key]);
+    }
+    if (!m_selectedScrap.empty())
+    {
+        lines << scrapTotalText();
+    }
+    m_entitySummaryLabel->setText(lines.join('\n'));
+    m_entitySummaryLabel->show();
 }
 
 void SelectedBuildingPanel::buildEntityShip(entt::entity entity)
@@ -1016,23 +1133,17 @@ void SelectedBuildingPanel::buildEntityStation(entt::entity entity)
 
 void SelectedBuildingPanel::refreshEntityStats()
 {
-    if (!m_selectedEntity.has_value()) { return; }
+    // Only the single-actor stats panel needs a live refresh; the multi-actor summary is
+    // static counts, and GameWorldView prunes dead/despawned actors and re-emits the
+    // selection (REQ-UI-ENTITY-CLICK-SELECT), so the panel does not mutate it here.
+    if (m_selectedEntities.size() != 1) { return; }
 
     EntityAdmin& admin = m_sim->getAdmin();
-    entt::entity entity = *m_selectedEntity;
-
-    if (!admin.isValid(entity))
-    {
-        clearEntityDisplay();
-        return;
-    }
+    const entt::entity entity = m_selectedEntities.front();
 
+    if (!admin.isValid(entity) || !admin.hasAll<HealthComponent>(entity)) { return; }
     const HealthComponent& health = admin.get<HealthComponent>(entity);
-    if (health.hp <= 0.0f)
-    {
-        clearEntityDisplay();
-        return;
-    }
+    if (health.hp <= 0.0f) { return; }
 
     if (admin.hasAll<ShipIdentityComponent>(entity))
     {
@@ -1049,10 +1160,11 @@ void SelectedBuildingPanel::refreshEntityStats()
 
 void SelectedBuildingPanel::clearEntityDisplay()
 {
-    m_selectedEntity = std::nullopt;
+    m_selectedEntities.clear();
     m_entityTitleLabel->hide();
     m_entityStatsPanel->hide();
     m_stationStatsLabel->hide();
+    m_entitySummaryLabel->hide();
 }
 
 void SelectedBuildingPanel::handleEvent(std::shared_ptr<const SelectionChangedEvent> event)
@@ -1066,34 +1178,14 @@ void SelectedBuildingPanel::handleEvent(
     m_selectedScrap = event->scrap;
     if (!m_selectedScrap.empty())
     {
-        // Scrap is its own selection category, mutually exclusive with buildings and
-        // entities (REQ-UI-SCRAP-CLICK-SELECT).
+        // Scrap is a field object: it supersedes any building selection but coexists
+        // with actors (REQ-UI-SELECTION-CATEGORIES).
         m_selectedBuildingIds.clear();
-        clearContent();
-        clearEntityDisplay();
-        buildScrap();
-    }
-    else
-    {
-        m_scrapLabel->hide();
-        if (m_selectedBuildingIds.empty() && !m_selectedEntity.has_value())
-        {
-            buildEmpty();
-        }
     }
+    buildFieldSelection();
 }
 
-void SelectedBuildingPanel::buildScrap()
-{
-    clearContent();
-    m_entityTitleLabel->hide();
-    m_entityStatsPanel->hide();
-    m_stationStatsLabel->hide();
-    refreshScrapTotal();
-    m_scrapLabel->show();
-}
-
-void SelectedBuildingPanel::refreshScrapTotal()
+QString SelectedBuildingPanel::scrapTotalText() const
 {
     // Sum the remaining amounts of the still-living selected piles (REQ-UI-SCRAP-PANEL).
     int total = 0;
@@ -1105,7 +1197,12 @@ void SelectedBuildingPanel::refreshScrapTotal()
             total += info.amount;
         }
     }
-    m_scrapLabel->setText(tr("Scrap: %1").arg(total));
+    return tr("Scrap x %1").arg(total);
+}
+
+void SelectedBuildingPanel::refreshScrapTotal()
+{
+    m_scrapLabel->setText(scrapTotalText());
 }
 
 void SelectedBuildingPanel::handleEvent(std::shared_ptr<const DebugDrawToggledEvent> event)