tools/chatgui: Qt5 GUI chat app stub with tray, channel list, message bubbles

tools/chatgui/src/messagedelegate.h

@@ -0,0 +1,67 @@
+#pragma once
+
+#include <QStyledItemDelegate>
+
+enum MessageDataRole {
+    MsgAuthorRole       = Qt::UserRole + 1,
+    MsgTextRole         = Qt::UserRole + 2,
+    MsgTimeRole         = Qt::UserRole + 3,
+    MsgEditedRole       = Qt::UserRole + 4,
+    MsgAvatarRole       = Qt::UserRole + 5,
+    MsgHasQuoteRole     = Qt::UserRole + 6,
+    MsgQuoteAuthorRole  = Qt::UserRole + 7,
+    MsgQuoteTextRole    = Qt::UserRole + 8,
+    MsgReactionsRole    = Qt::UserRole + 9,
+};
+
+class MessageDelegate : public QStyledItemDelegate {
+    Q_OBJECT
+public:
+    explicit MessageDelegate(QObject *parent = nullptr);
+
+    void paint(QPainter *painter, const QStyleOptionViewItem &option,
+               const QModelIndex &index) const override;
+    QSize sizeHint(const QStyleOptionViewItem &option,
+                   const QModelIndex &index) const override;
+
+private:
+    struct Layout {
+        int viewWidth;
+        int bubbleWidth;
+        QRect avatarRect;
+        QRect bubbleRect;
+        QRect quoteRect;
+        QRect quoteBarRect;
+        QRect quoteAuthorRect;
+        QRect quoteTextRect;
+        QRect textRect;
+        QRect statusRect;
+        int totalHeight;
+    };
+
+    Layout calcLayout(const QStyleOptionViewItem &option,
+                      const QModelIndex &index) const;
+    void drawQuote(QPainter *p, const Layout &L,
+                   const QModelIndex &index, const QStyleOptionViewItem &opt) const;
+    void drawBubble(QPainter *p, const Layout &L) const;
+    void drawStatusBar(QPainter *p, const Layout &L,
+                       const QModelIndex &index, const QStyleOptionViewItem &opt) const;
+    void drawAvatar(QPainter *p, const Layout &L,
+                    const QModelIndex &index) const;
+
+    static constexpr int kAvatar   = 36;
+    static constexpr int kGap      = 8;
+    static constexpr int kRadius   = 10;
+    static constexpr int kPadH     = 12;
+    static constexpr int kPadTop   = 8;
+    static constexpr int kPadBot   = 6;
+    static constexpr int kTail     = 6;
+    static constexpr int kMarginH  = 8;
+    static constexpr int kItemGap  = 3;
+    static constexpr int kQuoteGap = 4;
+    static constexpr int kQuotePadH = 6;
+    static constexpr int kQuotePadV = 6;
+    static constexpr int kQuoteBarW = 2;
+    static constexpr int kQuoteAv  = 16;
+    static constexpr int kStatusH  = 18;
+};