Fix text-input support for new API

Update text input support to upstream text-input protocol v2 from
wayland-protocols. Remove support for input-method protocol for now.

Map text-input protocol on compositor side to the Qt input method API,
this allows to use any qt platform input method on compositor side
(especially qtvirtualkeyboard). Add support for qtvirtualkeyboard to
pure-qml example.

Implement all missing functions of the text-input protocol.

Change-Id: I597451ff65454a63dff86026b6a8d1ffbe07ce02
Done-with: Zeno Endemann <zeno.endemann@kdab.com>
Reviewed-by: Giulio Camuffo <giulio.camuffo@kdab.com>

4 files changed, 435 insertions, 0 deletions

diff --git a/src/shared/qwaylandinputmethodeventbuilder.cpp b/src/shared/qwaylandinputmethodeventbuilder.cpp
new file mode 100644
index 000000000..eb527c15a
--- /dev/null
+++ b/src/shared/qwaylandinputmethodeventbuilder.cpp
@@ -0,0 +1,286 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the plugins of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qwaylandinputmethodeventbuilder.h"
+
+#include <QInputMethod>
+#include <QTextCharFormat>
+
+#ifdef QT_BUILD_WAYLANDCOMPOSITOR_LIB
+#include <QtWaylandCompositor/private/qwayland-server-text-input-unstable-v2.h>
+#else
+#include <QtWaylandClient/private/qwayland-text-input-unstable-v2.h>
+#endif
+
+QT_BEGIN_NAMESPACE
+
+QWaylandInputMethodEventBuilder::QWaylandInputMethodEventBuilder()
+    : m_anchor(0)
+    , m_cursor(0)
+    , m_deleteBefore(0)
+    , m_deleteAfter(0)
+    , m_preeditCursor(0)
+    , m_preeditStyles()
+{
+}
+
+QWaylandInputMethodEventBuilder::~QWaylandInputMethodEventBuilder()
+{
+}
+
+void QWaylandInputMethodEventBuilder::reset()
+{
+    m_anchor = 0;
+    m_cursor = 0;
+    m_deleteBefore = 0;
+    m_deleteAfter = 0;
+    m_preeditCursor = 0;
+    m_preeditStyles.clear();
+}
+
+void QWaylandInputMethodEventBuilder::setCursorPosition(int32_t index, int32_t anchor)
+{
+    m_cursor = index;
+    m_anchor = anchor;
+}
+
+void QWaylandInputMethodEventBuilder::setDeleteSurroundingText(uint32_t beforeLength, uint32_t afterLength)
+{
+    m_deleteBefore = beforeLength;
+    m_deleteAfter = afterLength;
+}
+
+void QWaylandInputMethodEventBuilder::addPreeditStyling(uint32_t index, uint32_t length, uint32_t style)
+{
+    QTextCharFormat format;
+
+    switch (style) {
+    case 0:
+    case 1:
+        format.setFontUnderline(true);
+        format.setUnderlineStyle(QTextCharFormat::SingleUnderline);
+        m_preeditStyles.append(QInputMethodEvent::Attribute(QInputMethodEvent::TextFormat, index, length, format));
+        break;
+    case 2:
+    case 3:
+        format.setFontWeight(QFont::Bold);
+        format.setFontUnderline(true);
+        format.setUnderlineStyle(QTextCharFormat::SingleUnderline);
+        m_preeditStyles.append(QInputMethodEvent::Attribute(QInputMethodEvent::TextFormat, index, length, format));
+        break;
+    case 4:
+        format.setFontUnderline(true);
+        format.setUnderlineStyle(QTextCharFormat::SingleUnderline);
+        m_preeditStyles.append(QInputMethodEvent::Attribute(QInputMethodEvent::TextFormat, index, length, format));
+    case 5:
+        format.setFontUnderline(true);
+        format.setUnderlineStyle(QTextCharFormat::WaveUnderline);
+        format.setUnderlineColor(QColor(Qt::red));
+        m_preeditStyles.append(QInputMethodEvent::Attribute(QInputMethodEvent::TextFormat, index, length, format));
+        break;
+//    case QtWayland::wl_text_input::preedit_style_selection:
+//    case QtWayland::wl_text_input::preedit_style_none:
+    default:
+        break;
+    }
+}
+
+void QWaylandInputMethodEventBuilder::setPreeditCursor(int32_t index)
+{
+    m_preeditCursor = index;
+}
+
+QInputMethodEvent QWaylandInputMethodEventBuilder::buildCommit(const QString &text)
+{
+    QList<QInputMethodEvent::Attribute> attributes;
+
+    const QPair<int, int> replacement = replacementForDeleteSurrounding();
+
+    if (m_cursor != 0 || m_anchor != 0) {
+        QString surrounding = QInputMethod::queryFocusObject(Qt::ImSurroundingText, QVariant()).toString();
+        const int cursor = QInputMethod::queryFocusObject(Qt::ImCursorPosition, QVariant()).toInt();
+        const int anchor = QInputMethod::queryFocusObject(Qt::ImAnchorPosition, QVariant()).toInt();
+        const int absoluteCursor = QInputMethod::queryFocusObject(Qt::ImAbsolutePosition, QVariant()).toInt();
+
+        const int absoluteOffset = absoluteCursor - cursor;
+
+        const int cursorAfterCommit = qMin(anchor, cursor) + replacement.first + text.length();
+        surrounding.replace(qMin(anchor, cursor) + replacement.first,
+                            qAbs(anchor - cursor) + replacement.second, text);
+
+        attributes.push_back(QInputMethodEvent::Attribute(QInputMethodEvent::Selection,
+                                                          indexFromWayland(surrounding, m_cursor, cursorAfterCommit) + absoluteOffset,
+                                                          indexFromWayland(surrounding, m_anchor, cursorAfterCommit) + absoluteOffset,
+                                                          QVariant()));
+    }
+
+    QInputMethodEvent event(QString(), attributes);
+    event.setCommitString(text, replacement.first, replacement.second);
+
+    return event;
+}
+
+QInputMethodEvent QWaylandInputMethodEventBuilder::buildPreedit(const QString &text)
+{
+    QList<QInputMethodEvent::Attribute> attributes;
+
+    if (m_preeditCursor < 0) {
+        attributes.append(QInputMethodEvent::Attribute(QInputMethodEvent::Cursor, 0, 0, QVariant()));
+    } else if (m_preeditCursor > 0) {
+        attributes.append(QInputMethodEvent::Attribute(QInputMethodEvent::Cursor, indexFromWayland(text, m_preeditCursor), 1, QVariant()));
+    }
+
+    Q_FOREACH (const QInputMethodEvent::Attribute &attr, m_preeditStyles) {
+        int start = indexFromWayland(text, attr.start);
+        int length = indexFromWayland(text, attr.start + attr.length) - start;
+        attributes.append(QInputMethodEvent::Attribute(attr.type, start, length, attr.value));
+    }
+
+    QInputMethodEvent event(text, attributes);
+
+    const QPair<int, int> replacement = replacementForDeleteSurrounding();
+    event.setCommitString(QString(), replacement.first, replacement.second);
+
+    return event;
+}
+
+QPair<int, int> QWaylandInputMethodEventBuilder::replacementForDeleteSurrounding()
+{
+    if (m_deleteBefore == 0 && m_deleteAfter == 0)
+        return QPair<int, int>(0, 0);
+
+    const QString &surrounding = QInputMethod::queryFocusObject(Qt::ImSurroundingText, QVariant()).toString();
+    const int cursor = QInputMethod::queryFocusObject(Qt::ImCursorPosition, QVariant()).toInt();
+    const int anchor = QInputMethod::queryFocusObject(Qt::ImAnchorPosition, QVariant()).toInt();
+
+    const int selectionStart = qMin(cursor, anchor);
+    const int selectionEnd = qMax(cursor, anchor);
+
+    const int deleteBefore = selectionStart - indexFromWayland(surrounding, -m_deleteBefore, selectionStart);
+    const int deleteAfter = indexFromWayland(surrounding, m_deleteAfter, selectionEnd) - selectionEnd;
+
+    return QPair<int, int>(-deleteBefore, deleteBefore + deleteAfter);
+}
+
+QWaylandInputMethodContentType QWaylandInputMethodContentType::convert(Qt::InputMethodHints hints)
+{
+    uint32_t hint = ZWP_TEXT_INPUT_V2_CONTENT_HINT_NONE;
+    uint32_t purpose = ZWP_TEXT_INPUT_V2_CONTENT_PURPOSE_NORMAL;
+
+    if (hints & Qt::ImhHiddenText) {
+        hint |= ZWP_TEXT_INPUT_V2_CONTENT_HINT_HIDDEN_TEXT;
+    }
+    if (hints & Qt::ImhSensitiveData) {
+        hint |= ZWP_TEXT_INPUT_V2_CONTENT_HINT_SENSITIVE_DATA;
+    }
+    if ((hints & Qt::ImhNoAutoUppercase) == 0) {
+        hint |= ZWP_TEXT_INPUT_V2_CONTENT_HINT_AUTO_CAPITALIZATION;
+    }
+    if (hints & Qt::ImhPreferNumbers) {
+        // Nothing yet
+    }
+    if (hints & Qt::ImhPreferUppercase) {
+        hint |= ZWP_TEXT_INPUT_V2_CONTENT_HINT_UPPERCASE;
+    }
+    if (hints & Qt::ImhPreferLowercase) {
+        hint |= ZWP_TEXT_INPUT_V2_CONTENT_HINT_LOWERCASE;
+    }
+    if ((hints & Qt::ImhNoPredictiveText) == 0) {
+        hint |= ZWP_TEXT_INPUT_V2_CONTENT_HINT_AUTO_COMPLETION | ZWP_TEXT_INPUT_V2_CONTENT_HINT_AUTO_CORRECTION;
+    }
+
+    if ((hints & Qt::ImhDate) && (hints & Qt::ImhTime) == 0) {
+        purpose = ZWP_TEXT_INPUT_V2_CONTENT_PURPOSE_DATE;
+    } else if ((hints & Qt::ImhDate) && (hints & Qt::ImhTime)) {
+        purpose = ZWP_TEXT_INPUT_V2_CONTENT_PURPOSE_DATETIME;
+    } else if ((hints & Qt::ImhDate) == 0 && (hints & Qt::ImhTime)) {
+        purpose = ZWP_TEXT_INPUT_V2_CONTENT_PURPOSE_TIME;
+    }
+
+    if (hints & Qt::ImhPreferLatin) {
+        hint |= ZWP_TEXT_INPUT_V2_CONTENT_HINT_LATIN;
+    }
+
+    if (hints & Qt::ImhMultiLine) {
+        hint |= ZWP_TEXT_INPUT_V2_CONTENT_HINT_MULTILINE;
+    }
+
+    if (hints & Qt::ImhDigitsOnly) {
+        purpose = ZWP_TEXT_INPUT_V2_CONTENT_PURPOSE_DIGITS;
+    }
+    if (hints & Qt::ImhFormattedNumbersOnly) {
+        purpose = ZWP_TEXT_INPUT_V2_CONTENT_PURPOSE_NUMBER;
+    }
+    if (hints & Qt::ImhUppercaseOnly) {
+        hint |= ZWP_TEXT_INPUT_V2_CONTENT_HINT_UPPERCASE;
+    }
+    if (hints & Qt::ImhLowercaseOnly) {
+        hint |= ZWP_TEXT_INPUT_V2_CONTENT_HINT_LOWERCASE;
+    }
+    if (hints & Qt::ImhDialableCharactersOnly) {
+        purpose = ZWP_TEXT_INPUT_V2_CONTENT_PURPOSE_PHONE;
+    }
+    if (hints & Qt::ImhEmailCharactersOnly) {
+       purpose = ZWP_TEXT_INPUT_V2_CONTENT_PURPOSE_EMAIL;
+    }
+    if (hints & Qt::ImhUrlCharactersOnly) {
+       purpose = ZWP_TEXT_INPUT_V2_CONTENT_PURPOSE_URL;
+    }
+    if (hints & Qt::ImhLatinOnly) {
+        hint |= ZWP_TEXT_INPUT_V2_CONTENT_HINT_LATIN;
+    }
+    return QWaylandInputMethodContentType{hint, purpose};
+}
+
+int QWaylandInputMethodEventBuilder::indexFromWayland(const QString &str, int utf8Index, int baseIndex)
+{
+    if (utf8Index == 0)
+        return baseIndex;
+
+    if (utf8Index < 0) {
+        const QByteArray &utf8 = str.leftRef(baseIndex).toUtf8();
+        return QString::fromUtf8(utf8.left(qMax(utf8.length() + utf8Index, 0))).length();
+    } else {
+        const QByteArray &utf8 = str.midRef(baseIndex).toUtf8();
+        return QString::fromUtf8(utf8.left(utf8Index)).length() + baseIndex;
+    }
+}
+
+QT_END_NAMESPACE
+
diff --git a/src/shared/qwaylandinputmethodeventbuilder.h b/src/shared/qwaylandinputmethodeventbuilder.h
new file mode 100644
index 000000000..188a6a94b
--- /dev/null
+++ b/src/shared/qwaylandinputmethodeventbuilder.h
@@ -0,0 +1,87 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the plugins of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QWAYLANDINPUTMETHODEVENTBUILDER_H
+#define QWAYLANDINPUTMETHODEVENTBUILDER_H
+
+#include <QInputMethodEvent>
+
+QT_BEGIN_NAMESPACE
+
+class QWaylandInputMethodEventBuilder
+{
+public:
+    QWaylandInputMethodEventBuilder();
+    ~QWaylandInputMethodEventBuilder();
+
+    void reset();
+
+    void setCursorPosition(int32_t index, int32_t anchor);
+    void setDeleteSurroundingText(uint32_t beforeLength, uint32_t afterLength);
+
+    void addPreeditStyling(uint32_t index, uint32_t length, uint32_t style);
+    void setPreeditCursor(int32_t index);
+
+    QInputMethodEvent buildCommit(const QString &text);
+    QInputMethodEvent buildPreedit(const QString &text);
+
+    static int indexFromWayland(const QString &str, int utf8Index, int baseIndex = 0);
+private:
+    QPair<int, int> replacementForDeleteSurrounding();
+
+    int32_t m_anchor;
+    int32_t m_cursor;
+    uint32_t m_deleteBefore;
+    uint32_t m_deleteAfter;
+
+    int32_t m_preeditCursor;
+    QList<QInputMethodEvent::Attribute> m_preeditStyles;
+};
+
+struct QWaylandInputMethodContentType {
+    uint32_t hint;
+    uint32_t purpose;
+
+    static QWaylandInputMethodContentType convert(Qt::InputMethodHints hints);
+};
+
+
+QT_END_NAMESPACE
+
+#endif // QWAYLANDINPUTMETHODEVENTBUILDER_H
diff --git a/src/shared/qwaylandxkb.cpp b/src/shared/qwaylandxkb.cpp
index f5d0527de..32d24bd62 100644
--- a/src/shared/qwaylandxkb.cpp
+++ b/src/shared/qwaylandxkb.cpp
@@ -40,6 +40,7 @@
 
 #include "qwaylandxkb.h"
 
+#include <QKeyEvent>
 #include <QString>
 
 #ifndef QT_NO_WAYLAND_XKB
@@ -282,6 +283,16 @@ static int lookupKeysym(xkb_keysym_t key)
     return code;
 }
 
+static xkb_keysym_t toKeysymFromTable(uint32_t key)
+{
+    for (int i = 0; KeyTbl[i]; i += 2) {
+        if (key == KeyTbl[i + 1])
+            return KeyTbl[i];
+    }
+
+    return 0;
+}
+
 int QWaylandXkb::keysymToQtKey(xkb_keysym_t keysym, Qt::KeyboardModifiers &modifiers, const QString &text)
 {
     int code = 0;
@@ -326,6 +337,50 @@ Qt::KeyboardModifiers QWaylandXkb::modifiers(struct xkb_state *state)
     return modifiers;
 }
 
+QEvent::Type QWaylandXkb::toQtEventType(uint32_t state)
+{
+    return state != 0 ? QEvent::KeyPress : QEvent::KeyRelease;
+}
+
+QString QWaylandXkb::textFromKeysym(uint32_t keysym, Qt::KeyboardModifiers modifiers)
+{
+    uint utf32 = xkb_keysym_to_utf32(keysym);
+
+    // Map control + letter to proper text
+    if (utf32 >= 'A' && utf32 <= '~' && (modifiers & Qt::ControlModifier)) {
+        utf32 &= ~0x60;
+        return QString::fromUcs4(&utf32, 1);
+    }
+
+    if (utf32)
+        return QString::fromUcs4(&utf32, 1);
+
+    return QString();
+}
+
+QVector<xkb_keysym_t> QWaylandXkb::toKeysym(QKeyEvent *event)
+{
+    QVector<xkb_keysym_t> keysyms;
+    if (event->key() >= Qt::Key_F1 && event->key() <= Qt::Key_F35) {
+        keysyms.append(XKB_KEY_F1 + (event->key() - Qt::Key_F1));
+    } else if (event->modifiers() & Qt::KeypadModifier) {
+        if (event->key() >= Qt::Key_0 && event->key() <= Qt::Key_9)
+            keysyms.append(XKB_KEY_KP_0 + (event->key() - Qt::Key_0));
+        else
+            keysyms.append(toKeysymFromTable(event->key()));
+    } else if (!event->text().isEmpty()) {
+        // From libxkbcommon keysym-utf.c:
+        // "We allow to represent any UCS character in the range U-00000000 to
+        // U-00FFFFFF by a keysym value in the range 0x01000000 to 0x01ffffff."
+        foreach (uint utf32, event->text().toUcs4()) {
+            keysyms.append(utf32 | 0x01000000);
+        }
+    } else {
+        keysyms.append(toKeysymFromTable(event->key()));
+    }
+    return keysyms;
+}
+
 QT_END_NAMESPACE
 
 #endif // QT_NO_WAYLAND_XKB
diff --git a/src/shared/qwaylandxkb.h b/src/shared/qwaylandxkb.h
index bfb38515f..9b5c935a5 100644
--- a/src/shared/qwaylandxkb.h
+++ b/src/shared/qwaylandxkb.h
@@ -44,15 +44,22 @@
 #ifndef QT_NO_WAYLAND_XKB
 
 #include <Qt>
+#include <QEvent>
 #include <xkbcommon/xkbcommon.h>
 
 QT_BEGIN_NAMESPACE
 
+class QKeyEvent;
+
 class QWaylandXkb
 {
 public:
     static int keysymToQtKey(xkb_keysym_t keysym, Qt::KeyboardModifiers &modifiers, const QString &text);
     static Qt::KeyboardModifiers modifiers(struct xkb_state *state);
+
+    static QEvent::Type toQtEventType(uint32_t state);
+    static QString textFromKeysym(uint32_t keysym, Qt::KeyboardModifiers modifiers);
+    static QVector<xkb_keysym_t> toKeysym(QKeyEvent *event);
 };
 
 QT_END_NAMESPACE