Closes #9

qt/dbc_tree_model.h

@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: MIT
+#ifndef DBC_TREE_MODEL_H
+#define DBC_TREE_MODEL_H
+
+#include "tree_node.h"
+#include <QAbstractItemModel>
+
+/** Read-only model. Owns an immutable tree; all indexes expire on SetTree().
+ * Use QPersistentModelIndex to observe reset invalidation. Call on the model thread.
+ */
+class DbcTreeModel : public QAbstractItemModel {
+public:
+    enum Column { Name,
+                  CanId,
+                  PayloadLength,
+                  StartBit,
+                  BitLength,
+                  ByteOrder,
+                  Signed,
+                  Unit,
+                  Comment,
+                  ColumnCount };
+    // Metadata roles apply on every column; inapplicable roles return invalid QVariant.
+    enum Role { NodeTypeRole = Qt::UserRole + 1,
+                CanIdRole,
+                PayloadLengthRole,
+                StartBitRole,
+                BitLengthRole,
+                LittleEndianRole,
+                SignedRole,
+                UnitRole,
+                CommentRole,
+                ValueDescriptionsRole,
+                ExtendedRole };
+
+    explicit DbcTreeModel(QObject *parent = nullptr);
+    void SetTree(std::unique_ptr<TreeNode> root);
+    QModelIndex index(int row, int column, const QModelIndex &parent = QModelIndex()) const override;
+    QModelIndex parent(const QModelIndex &child) const override;
+    int rowCount(const QModelIndex &parent = QModelIndex()) const override;
+    int columnCount(const QModelIndex &parent = QModelIndex()) const override;
+    QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const override;
+    QVariant headerData(int section, Qt::Orientation orientation, int role = Qt::DisplayRole) const override;
+    Qt::ItemFlags flags(const QModelIndex &index) const override;
+
+private:
+    const TreeNode *Node(const QModelIndex &index) const;
+    std::unique_ptr<TreeNode> m_root;
+};
+#endif