Closes #9

qt/dbc_tree_model.cpp

@@ -0,0 +1,128 @@
+// SPDX-License-Identifier: MIT
+#include "dbc_tree_model.h"
+#include <QVariantList>
+#include <QVariantMap>
+#include <limits>
+#include <stdexcept>
+
+DbcTreeModel::DbcTreeModel(QObject *parent) : QAbstractItemModel(parent) {}
+
+void DbcTreeModel::SetTree(std::unique_ptr<TreeNode> root) {
+    if (root && (root->GetType() != NodeType::Root || root->GetParent()))
+        throw std::invalid_argument("Model requires a detached root node");
+    beginResetModel();
+    m_root = std::move(root);
+    endResetModel();
+}
+
+const TreeNode *DbcTreeModel::Node(const QModelIndex &index) const {
+    if (!index.isValid() || index.model() != this || index.column() < 0 ||
+        index.column() >= ColumnCount || index.row() < 0)
+        return nullptr;
+    return static_cast<const TreeNode *>(index.internalPointer());
+}
+
+QModelIndex DbcTreeModel::index(int row, int column, const QModelIndex &parentIndex) const {
+    if (row < 0 || column < 0 || column >= ColumnCount ||
+        (parentIndex.isValid() && parentIndex.column() != 0))
+        return {};
+    const TreeNode *owner = parentIndex.isValid() ? Node(parentIndex) : m_root.get();
+    if (!owner)
+        return {};
+    const TreeNode *child = owner->GetChild(static_cast<std::size_t>(row));
+    return child ? createIndex(row, column, const_cast<TreeNode *>(child)) : QModelIndex();
+}
+
+QModelIndex DbcTreeModel::parent(const QModelIndex &childIndex) const {
+    const TreeNode *child = Node(childIndex);
+    const TreeNode *owner = child ? child->GetParent() : nullptr;
+    if (!owner || owner == m_root.get())
+        return {};
+    return createIndex(static_cast<int>(owner->GetRow()), 0, const_cast<TreeNode *>(owner));
+}
+
+int DbcTreeModel::rowCount(const QModelIndex &parentIndex) const {
+    if (parentIndex.isValid() && parentIndex.column() != 0)
+        return 0;
+    const TreeNode *owner = parentIndex.isValid() ? Node(parentIndex) : m_root.get();
+    if (!owner)
+        return 0;
+    return static_cast<int>(qMin(owner->GetChildCount(), static_cast<std::size_t>(std::numeric_limits<int>::max())));
+}
+
+int DbcTreeModel::columnCount(const QModelIndex &parentIndex) const {
+    return parentIndex.isValid() && !Node(parentIndex) ? 0 : ColumnCount;
+}
+
+QVariant DbcTreeModel::data(const QModelIndex &item, int role) const {
+    const TreeNode *node = Node(item);
+    if (!node)
+        return {};
+    const FrameInfo *frame = node->GetFrame();
+    const SignalInfo *signal = node->GetSignal();
+    const QString comment = QString::fromStdString(frame ? frame->comment : signal ? signal->comment
+                                                                                   : "");
+    if (role == Qt::ToolTipRole || role == CommentRole)
+        return comment;
+    if (role == NodeTypeRole)
+        return static_cast<int>(node->GetType());
+    if (role == ValueDescriptionsRole && signal) {
+        QVariantList descriptions;
+        for (const auto &entry: signal->valueDescriptions) {
+            QVariantMap pair;
+            if (const auto *number = std::get_if<std::int64_t>(&entry.first))
+                pair.insert("value", QVariant::fromValue(static_cast<qlonglong>(*number)));
+            else
+                pair.insert("value", QVariant::fromValue(static_cast<qulonglong>(std::get<std::uint64_t>(entry.first))));
+            pair.insert("description", QString::fromStdString(entry.second));
+            descriptions.append(pair);
+        }
+        return descriptions;
+    }
+    if (frame) {
+        if (role == CanIdRole) return frame->canId;
+        if (role == PayloadLengthRole) return static_cast<int>(frame->dlc);
+        if (role == ExtendedRole) return frame->isExtended;
+    }
+    if (signal) {
+        if (role == StartBitRole) return signal->startBit;
+        if (role == BitLengthRole) return signal->length;
+        if (role == LittleEndianRole) return signal->isLittleEndian;
+        if (role == SignedRole) return signal->isSigned;
+        if (role == UnitRole) return QString::fromStdString(signal->unit);
+    }
+    if (role != Qt::DisplayRole) return {};
+    switch (item.column()) {
+        case Name:
+            return QString::fromStdString(node->GetName());
+        case CanId:
+            return frame ? QVariant(QString("0x%1").arg(frame->canId, 0, 16).toUpper()) : QVariant();
+        case PayloadLength:
+            return frame ? QVariant(static_cast<int>(frame->dlc)) : QVariant();
+        case StartBit:
+            return signal ? QVariant(signal->startBit) : QVariant();
+        case BitLength:
+            return signal ? QVariant(signal->length) : QVariant();
+        case ByteOrder:
+            return signal ? QVariant(signal->isLittleEndian ? "Intel" : "Motorola") : QVariant();
+        case Signed:
+            return signal ? QVariant(signal->isSigned ? "Signed" : "Unsigned") : QVariant();
+        case Unit:
+            return signal ? QVariant(QString::fromStdString(signal->unit)) : QVariant();
+        case Comment:
+            return comment;
+        default:
+            return {};
+    }
+}
+
+QVariant DbcTreeModel::headerData(int section, Qt::Orientation orientation, int role) const {
+    static const char *const headers[] = {"Name", "CAN ID", "Payload (bytes)", "Start bit", "Length (bits)", "Byte order", "Signedness", "Unit", "Comment"};
+    if (orientation != Qt::Horizontal || role != Qt::DisplayRole || section < 0 || section >= ColumnCount)
+        return {};
+    return QString::fromLatin1(headers[section]);
+}
+
+Qt::ItemFlags DbcTreeModel::flags(const QModelIndex &item) const {
+    return Node(item) ? Qt::ItemIsEnabled | Qt::ItemIsSelectable : Qt::NoItemFlags;
+}

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

qt/qt.pri

@@ -0,0 +1,11 @@
+include($$PWD/../core/core.pri)
+QT += core
+INCLUDEPATH += $$PWD
+isEmpty(DBC_QT_BUILD_DIR): DBC_QT_BUILD_DIR = $$clean_path($$OUT_PWD/../qt)
+# Put the adapter before core for static linker dependency ordering.
+LIBS = -L$$DBC_QT_BUILD_DIR -ldbc_qt $$LIBS
+win32-msvc*: DBC_QT_LIBRARY = $$DBC_QT_BUILD_DIR/dbc_qt.lib
+else: DBC_QT_LIBRARY = $$DBC_QT_BUILD_DIR/libdbc_qt.a
+PRE_TARGETDEPS += $$DBC_QT_LIBRARY
+
+CONFIG += no_keywords

qt/qt.pro

@@ -0,0 +1,11 @@
+TEMPLATE = lib
+TARGET = dbc_qt
+CONFIG += staticlib c++17
+QT += core
+QT -= gui
+include(../core/core.pri)
+HEADERS += dbc_tree_model.h
+SOURCES += dbc_tree_model.cpp
+CONFIG -= debug_and_release debug_and_release_target
+
+CONFIG += no_keywords