macOS: Move key mapping from QtCore to platform plugin

There's a bunch of similar and overlapping logic in QCocoaKeyMapper
already. Moving it to the same place allows us to easier find ways
to reduce the overlap.

None of the exported functions were used outside of the plugin.

Change-Id: I6953690cdfda5ee8265b33ccbf919184c3a1700f
Reviewed-by: Timur Pocheptsov <timur.pocheptsov@qt.io>

1 files changed, 142 insertions, 0 deletions

diff --git a/src/plugins/platforms/cocoa/qcocoakeymapper.mm b/src/plugins/platforms/cocoa/qcocoakeymapper.mm
index 40d13e2d6a..fdb4fb01e7 100644
--- a/src/plugins/platforms/cocoa/qcocoakeymapper.mm
+++ b/src/plugins/platforms/cocoa/qcocoakeymapper.mm
@@ -295,6 +295,148 @@ static int toKeyCode(const QChar &key, int virtualKey, int modifiers)
     return Qt::Key_unknown;
 }
 
+// --------- Cocoa key mapping moved from Qt Core ---------
+
+// Use this method to keep all the information in the TextSegment. As long as it is ordered
+// we are in OK shape, and we can influence that ourselves.
+struct KeyPair
+{
+    QChar cocoaKey;
+    Qt::Key qtKey;
+};
+
+bool operator==(const KeyPair &entry, QChar qchar)
+{
+    return entry.cocoaKey == qchar;
+}
+
+bool operator<(const KeyPair &entry, QChar qchar)
+{
+    return entry.cocoaKey < qchar;
+}
+
+bool operator<(QChar qchar, const KeyPair &entry)
+{
+    return qchar < entry.cocoaKey;
+}
+
+bool operator<(const Qt::Key &key, const KeyPair &entry)
+{
+    return key < entry.qtKey;
+}
+
+bool operator<(const KeyPair &entry, const Qt::Key &key)
+{
+    return entry.qtKey < key;
+}
+
+struct qtKey2CocoaKeySortLessThan
+{
+    typedef bool result_type;
+    Q_DECL_CONSTEXPR result_type operator()(const KeyPair &entry1, const KeyPair &entry2) const noexcept
+    {
+        return entry1.qtKey < entry2.qtKey;
+    }
+};
+
+static const int NSEscapeCharacter = 27; // not defined by Cocoa headers
+static const int NumEntries = 59;
+static const KeyPair entries[NumEntries] = {
+    { NSEnterCharacter, Qt::Key_Enter },
+    { NSBackspaceCharacter, Qt::Key_Backspace },
+    { NSTabCharacter, Qt::Key_Tab },
+    { NSNewlineCharacter, Qt::Key_Return },
+    { NSCarriageReturnCharacter, Qt::Key_Return },
+    { NSBackTabCharacter, Qt::Key_Backtab },
+    { NSEscapeCharacter, Qt::Key_Escape },
+    // Cocoa sends us delete when pressing backspace!
+    // (NB when we reverse this list in qtKey2CocoaKey, there
+    // will be two indices of Qt::Key_Backspace. But is seems to work
+    // ok for menu shortcuts (which uses that function):
+    { NSDeleteCharacter, Qt::Key_Backspace },
+    { NSUpArrowFunctionKey, Qt::Key_Up },
+    { NSDownArrowFunctionKey, Qt::Key_Down },
+    { NSLeftArrowFunctionKey, Qt::Key_Left },
+    { NSRightArrowFunctionKey, Qt::Key_Right },
+    { NSF1FunctionKey, Qt::Key_F1 },
+    { NSF2FunctionKey, Qt::Key_F2 },
+    { NSF3FunctionKey, Qt::Key_F3 },
+    { NSF4FunctionKey, Qt::Key_F4 },
+    { NSF5FunctionKey, Qt::Key_F5 },
+    { NSF6FunctionKey, Qt::Key_F6 },
+    { NSF7FunctionKey, Qt::Key_F7 },
+    { NSF8FunctionKey, Qt::Key_F8 },
+    { NSF9FunctionKey, Qt::Key_F9 },
+    { NSF10FunctionKey, Qt::Key_F10 },
+    { NSF11FunctionKey, Qt::Key_F11 },
+    { NSF12FunctionKey, Qt::Key_F12 },
+    { NSF13FunctionKey, Qt::Key_F13 },
+    { NSF14FunctionKey, Qt::Key_F14 },
+    { NSF15FunctionKey, Qt::Key_F15 },
+    { NSF16FunctionKey, Qt::Key_F16 },
+    { NSF17FunctionKey, Qt::Key_F17 },
+    { NSF18FunctionKey, Qt::Key_F18 },
+    { NSF19FunctionKey, Qt::Key_F19 },
+    { NSF20FunctionKey, Qt::Key_F20 },
+    { NSF21FunctionKey, Qt::Key_F21 },
+    { NSF22FunctionKey, Qt::Key_F22 },
+    { NSF23FunctionKey, Qt::Key_F23 },
+    { NSF24FunctionKey, Qt::Key_F24 },
+    { NSF25FunctionKey, Qt::Key_F25 },
+    { NSF26FunctionKey, Qt::Key_F26 },
+    { NSF27FunctionKey, Qt::Key_F27 },
+    { NSF28FunctionKey, Qt::Key_F28 },
+    { NSF29FunctionKey, Qt::Key_F29 },
+    { NSF30FunctionKey, Qt::Key_F30 },
+    { NSF31FunctionKey, Qt::Key_F31 },
+    { NSF32FunctionKey, Qt::Key_F32 },
+    { NSF33FunctionKey, Qt::Key_F33 },
+    { NSF34FunctionKey, Qt::Key_F34 },
+    { NSF35FunctionKey, Qt::Key_F35 },
+    { NSInsertFunctionKey, Qt::Key_Insert },
+    { NSDeleteFunctionKey, Qt::Key_Delete },
+    { NSHomeFunctionKey, Qt::Key_Home },
+    { NSEndFunctionKey, Qt::Key_End },
+    { NSPageUpFunctionKey, Qt::Key_PageUp },
+    { NSPageDownFunctionKey, Qt::Key_PageDown },
+    { NSPrintScreenFunctionKey, Qt::Key_Print },
+    { NSScrollLockFunctionKey, Qt::Key_ScrollLock },
+    { NSPauseFunctionKey, Qt::Key_Pause },
+    { NSSysReqFunctionKey, Qt::Key_SysReq },
+    { NSMenuFunctionKey, Qt::Key_Menu },
+    { NSHelpFunctionKey, Qt::Key_Help },
+};
+static const KeyPair * const end = entries + NumEntries;
+
+QChar QCocoaKeyMapper::toCocoaKey(Qt::Key key)
+{
+    // The first time this function is called, create a reverse
+    // lookup table sorted on Qt Key rather than Cocoa key:
+    static QVector<KeyPair> rev_entries(NumEntries);
+    static bool mustInit = true;
+    if (mustInit){
+        mustInit = false;
+        for (int i=0; i<NumEntries; ++i)
+            rev_entries[i] = entries[i];
+        std::sort(rev_entries.begin(), rev_entries.end(), qtKey2CocoaKeySortLessThan());
+    }
+    const QVector<KeyPair>::iterator i
+            = std::lower_bound(rev_entries.begin(), rev_entries.end(), key);
+    if ((i == rev_entries.end()) || (key < *i))
+        return QChar();
+    return i->cocoaKey;
+}
+
+Qt::Key QCocoaKeyMapper::fromCocoaKey(QChar keyCode)
+{
+    const KeyPair *i = std::lower_bound(entries, end, keyCode);
+    if ((i == end) || (keyCode < *i))
+        return Qt::Key(keyCode.toUpper().unicode());
+    return i->qtKey;
+}
+
+// ------------------------------------------------
+
 QCocoaKeyMapper::QCocoaKeyMapper()
 {
     memset(m_keyLayout, 0, sizeof(m_keyLayout));