Support TextInput V3 over v4-wip

Support for v4-wip was not added into any desktop linux compositors, nor
was it ever enabled into the default Qt client builds for clients or
compositor.

TextInputV3 has become the most widely deployed. Whilst changes are
needed, they do not need to be breaking changes. A second iteration of
V3 can add the features we need. This is now in motion upstream.

For cases where QtWaylandCompositor is used, the custom Qt text input
method is preferred to work with the Qt virtual keyboard.

Pick-to: 6.7
Change-Id: I01e2686c67846804c0069f1495952b530547f91c
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@qt.io>

2 files changed, 47 insertions, 56 deletions

diff --git a/src/3rdparty/protocol/qt_attribution.json b/src/3rdparty/protocol/qt_attribution.json
index e30cb1b69..33a4f17c4 100644
--- a/src/3rdparty/protocol/qt_attribution.json
+++ b/src/3rdparty/protocol/qt_attribution.json
@@ -119,17 +119,18 @@
     },
 
     {
-        "Id": "wayland-text-input-unstable-v4-wip",
+        "Id": "wayland-text-input-unstable-v3",
         "Name": "Wayland Text Input Protocol",
         "QDocModule": "qtwaylandcompositor",
         "QtUsage": "Used in the Qt Wayland Compositor, and the Qt Wayland platform plugin.",
-        "Files": "text-input-unstable-v4-wip.xml",
+        "Files": "text-input-unstable-v3.xml",
         "Description": "Adds support for compositors to act as input methods and send text to applications.",
         "Homepage": "https://wayland.freedesktop.org",
-        "Version": "unstable v4, WIP",
-        "LicenseId": "HPND",
-        "License": "HPND License",
-        "LicenseFile": "HPND_LICENSE.txt",
+        "Version": "unstable v3",
+        "DownloadLocation": "https://cgit.freedesktop.org/wayland/wayland-protocols/plain/unstable/text-input/text-input-unstable-v3.xml",
+        "LicenseId": "MIT",
+        "License": "MIT License",
+        "LicenseFile": "MIT_LICENSE.txt",
         "Copyright": "Copyright © 2012, 2013 Intel Corporation\nCopyright © 2015, 2016 Jan Arne Petersen\nCopyright © 2017, 2018 Red Hat, Inc.\nCopyright © 2018       Purism SPC"
     },
 
diff --git a/src/3rdparty/protocol/text-input-unstable-v4-wip.xml b/src/3rdparty/protocol/text-input-unstable-v3.xml
index 1041e6f74..1fae54d7b 100644
--- a/src/3rdparty/protocol/text-input-unstable-v4-wip.xml
+++ b/src/3rdparty/protocol/text-input-unstable-v3.xml
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 
-<protocol name="text_input_unstable_v4_wip">
+<protocol name="text_input_unstable_v3">
   <copyright>
     Copyright © 2012, 2013 Intel Corporation
     Copyright © 2015, 2016 Jan Arne Petersen
@@ -47,9 +47,9 @@
     interface version number is reset.
   </description>
 
-  <interface name="zwp_text_input_v4" version="1">
+  <interface name="zwp_text_input_v3" version="1">
     <description summary="text input">
-      The zwp_text_input_v4 interface represents text input and input methods
+      The zwp_text_input_v3 interface represents text input and input methods
       associated with a seat. It provides enter/leave events to follow the
       text input focus for a seat.
 
@@ -64,9 +64,9 @@
       Lengths must be measured between two valid indices.
 
       Focus moving throughout surfaces will result in the emission of
-      zwp_text_input_v4.enter and zwp_text_input_v4.leave events. The focused
-      surface must commit zwp_text_input_v4.enable and
-      zwp_text_input_v4.disable requests as the keyboard focus moves across
+      zwp_text_input_v3.enter and zwp_text_input_v3.leave events. The focused
+      surface must commit zwp_text_input_v3.enable and
+      zwp_text_input_v3.disable requests as the keyboard focus moves across
       editable and non-editable elements of the UI. Those two requests are not
       expected to be paired with each other, the compositor must be able to
       handle consecutive series of the same request.
@@ -91,9 +91,15 @@
 
         This request must be issued every time the active text input changes
         to a new one, including within the current surface. Use
-        zwp_text_input_v4.disable when there is no longer any input focus on
+        zwp_text_input_v3.disable when there is no longer any input focus on
         the current surface.
 
+        Clients must not enable more than one text input on the single seat
+        and should disable the current text input before enabling the new one.
+        At most one instance of text input may be in enabled state per instance,
+        Requests to enable the another text input when some text input is active
+        must be ignored by compositor.
+
         This request resets all state associated with previous enable, disable,
         set_surrounding_text, set_text_change_cause, set_content_type, and
         set_cursor_rectangle requests, as well as the state associated with
@@ -104,11 +110,11 @@
         functionality.
 
         State set with this request is double-buffered. It will get applied on
-        the next zwp_text_input_v4.commit request, and stay valid until the
+        the next zwp_text_input_v3.commit request, and stay valid until the
         next committed enable or disable request.
 
         The changes must be applied by the compositor after issuing a
-        zwp_text_input_v4.commit request.
+        zwp_text_input_v3.commit request.
       </description>
     </request>
 
@@ -118,7 +124,7 @@
         there is no focus on any text entry inside the surface).
 
         State set with this request is double-buffered. It will get applied on
-        the next zwp_text_input_v4.commit request.
+        the next zwp_text_input_v3.commit request.
       </description>
     </request>
 
@@ -149,7 +155,7 @@
         purpose of this event.
 
         Values set with this request are double-buffered. They will get applied
-        on the next zwp_text_input_v4.commit request, and stay valid until the
+        on the next zwp_text_input_v3.commit request, and stay valid until the
         next committed enable or disable request.
 
         The initial state for affected fields is empty, meaning that the text
@@ -182,7 +188,7 @@
         cause describes the source of the change.
 
         The value set with this request is double-buffered. It must be applied
-        and reset to initial at the next zwp_text_input_v4.commit request.
+        and reset to initial at the next zwp_text_input_v3.commit request.
 
         The initial value of cause is input_method.
       </description>
@@ -238,7 +244,7 @@
         the behavior.
 
         Values set with this request are double-buffered. They will get applied
-        on the next zwp_text_input_v4.commit request.
+        on the next zwp_text_input_v3.commit request.
         Subsequent attempts to update them may have no effect. The values
         remain valid until the next committed enable or disable request.
 
@@ -261,7 +267,7 @@
         issue this request, to signify lack of support to the compositor.
 
         Values set with this request are double-buffered. They will get applied
-        on the next zwp_text_input_v4.commit request, and stay valid until the
+        on the next zwp_text_input_v3.commit request, and stay valid until the
         next committed enable or disable request.
 
         The initial values describing a cursor rectangle are empty. That means
@@ -298,7 +304,7 @@
         Neither current nor pending state are modified unless noted otherwise.
 
         The compositor must count the number of commit requests coming from
-        each zwp_text_input_v4 object and use the count as the serial in done
+        each zwp_text_input_v3 object and use the count as the serial in done
         events.
       </description>
     </request>
@@ -307,6 +313,9 @@
       <description summary="enter event">
         Notification that this seat's text-input focus is on a certain surface.
 
+        If client has created multiple text input objects, compositor must send
+        this event to all of them.
+
         When the seat has the keyboard capability the text-input focus follows
         the keyboard focus. This event sets the current surface for the
         text-input object.
@@ -321,7 +330,9 @@
         set.
 
         The leave notification clears the current surface. It is sent before
-        the enter notification for the new focus.
+        the enter notification for the new focus. After leave event, compositor
+        must ignore requests from any text input instances until next enter
+        event.
 
         When the seat has the keyboard capability the text-input focus follows
         the keyboard focus.
@@ -345,7 +356,7 @@
         the same, or as a text highlight otherwise.
 
         Values set with this event are double-buffered. They must be applied
-        and reset to initial on the next zwp_text_input_v4.done event.
+        and reset to initial on the next zwp_text_input_v3.done event.
 
         The initial value of text is an empty string, and cursor_begin,
         cursor_end and cursor_hidden are all 0.
@@ -362,7 +373,7 @@
         result of some composing (pre-edit).
 
         Values set with this event are double-buffered. They must be applied
-        and reset to initial on the next zwp_text_input_v4.done event.
+        and reset to initial on the next zwp_text_input_v3.done event.
 
         The initial value of text is an empty string.
       </description>
@@ -382,7 +393,7 @@
         sequence).
 
         Values set with this event are double-buffered. They must be applied
-        and reset to initial on the next zwp_text_input_v4.done event.
+        and reset to initial on the next zwp_text_input_v3.done event.
 
         The initial values of both before_length and after_length are 0.
       </description>
@@ -408,44 +419,23 @@
         5. Insert new preedit text in cursor position.
         6. Place cursor inside preedit text.
 
-        The serial number reflects the last state of the zwp_text_input_v4
+        The serial number reflects the last state of the zwp_text_input_v3
         object known to the compositor. The value of the serial argument must
         be equal to the number of commit requests already issued on that object.
+
         When the client receives a done event with a serial different than the
-        number of past commit requests, it must proceed as normal, except it
-        should not change the current state of the zwp_text_input_v4 object.
+        number of past commit requests, it must proceed with evaluating and
+        applying the changes as normal, except it should not change the current
+        state of the zwp_text_input_v3 object. All pending state requests
+        (set_surrounding_text, set_content_type and set_cursor_rectangle) on
+        the zwp_text_input_v3 object should be sent and committed after
+        receiving a zwp_text_input_v3.done event with a matching serial.
       </description>
       <arg name="serial" type="uint"/>
     </event>
-
-    <enum name="commit_mode">
-      <description summary="focus commit mode">
-        Pre-edit commit mode when the focus widget or the cursor position
-        is changed.
-      </description>
-      <entry name="clear" value="0" summary="pre-edit text is cleared"/>
-      <entry name="commit" value="1" summary="pre-edit text is committed"/>
-    </enum>
-
-    <event name="preedit_commit_mode">
-      <description summary="pre-edit commit mode">
-        Specify how the visible preedit should be handled
-        when switching the focus widget or changing the cursor position,
-        whether to commit the preedit text or clear the preedit text.
-
-        This is usually used together with the preedit_string event.
-
-        The commit behavior is the same for focus switch and
-        cursor position change.
-
-        The parameter mode selects the desired behavior and
-        its value is one from the commit mode enum.
-      </description>
-      <arg name="mode" type="uint" enum="commit_mode"/>
-    </event>
   </interface>
 
-  <interface name="zwp_text_input_manager_v4" version="1">
+  <interface name="zwp_text_input_manager_v3" version="1">
     <description summary="text input manager">
       A factory for text-input objects. This object is a global singleton.
     </description>
@@ -460,7 +450,7 @@
       <description summary="create a new text input object">
         Creates a new text-input object for a given seat.
       </description>
-      <arg name="id" type="new_id" interface="zwp_text_input_v4"/>
+      <arg name="id" type="new_id" interface="zwp_text_input_v3"/>
       <arg name="seat" type="object" interface="wl_seat"/>
     </request>
   </interface>