From 27788fb3bf62411c2b13d24bac45eb060483162f Mon Sep 17 00:00:00 2001

From: Daiki Ueno <ueno@unixuser.org>

Date: Tue, 8 Feb 2011 18:27:00 +0900

Subject: [PATCH] Support surrounding-text retrieval.

This change adds a new API function ibus_engine_get_surrounding_text().

In the implementation, engines do not proactively requests surrounding-text to

target applications via the GTK+ client (IBusIMContext) every time the

function is called.  Instead, IBusIMContext retrieves surrounding-text when

certain events occur in the input context (IBusInputContext) and maintains

it within the input context.

This logic is similar to Qt's QInputContext.  The following events trigger

surrounding-text retrieval:

- focus_in

- commit_text

- show_preedit_text

- (just before) process_key_event

Also,

- destroy

resets the current surrounding-text.

---

 bus/engineproxy.c               |   43 ++++++++++++

 bus/engineproxy.h               |   11 +++

 bus/inputcontext.c              |   36 ++++++++++

 client/gtk2/ibusimcontext.c     |  138 ++++++++++++++++++++++++++++++++++-----

 configure.ac                    |   14 ++++

 ibus/engine.py                  |    6 ++

 ibus/interface/iengine.py       |    3 +

 ibus/interface/iinputcontext.py |    5 ++

 src/ibusengine.c                |  138 +++++++++++++++++++++++++++++++++++++++

 src/ibusengine.h                |   21 ++++++-

 src/ibusenginedesc.c            |  132 +++++++++++++++++++++++++++++++++++++

 src/ibusenginedesc.h            |   11 +++

 src/ibusinputcontext.c          |   91 +++++++++++++++++++++++++

 src/ibusinputcontext.h          |   11 +++

 src/ibusmarshalers.list         |    1 +

 15 files changed, 644 insertions(+), 17 deletions(-)

diff --git a/bus/engineproxy.c b/bus/engineproxy.c

index f808727..b35933f 100644

--- a/bus/engineproxy.c

+++ b/bus/engineproxy.c

@@ -47,6 +47,10 @@ struct _BusEngineProxy {

     /* a key mapping for the engine that converts keycode into keysym. the mapping is used only when use_sys_layout is FALSE. */

     IBusKeymap     *keymap;

     /* private member */

+

+    /* surrounding text */

+    IBusText *surrounding_text;

+    guint     surrounding_cursor_pos;

 };

 struct _BusEngineProxyClass {

@@ -83,6 +87,8 @@ enum {

 static guint    engine_signals[LAST_SIGNAL] = { 0 };

+static IBusText *text_empty = NULL;

+

 /* functions prototype */

 static void     bus_engine_proxy_set_property   (BusEngineProxy      *engine,

                                                  guint                prop_id,

@@ -330,11 +336,16 @@ bus_engine_proxy_class_init (BusEngineProxyClass *class)

             G_TYPE_NONE,

             1,

             IBUS_TYPE_PROPERTY);

+

+    text_empty = ibus_text_new_from_static_string ("");

+    g_object_ref_sink (text_empty);

 }

 static void

 bus_engine_proxy_init (BusEngineProxy *engine)

 {

+    engine->surrounding_text = g_object_ref_sink (text_empty);

+    engine->surrounding_cursor_pos = 0;

 }

 static void

@@ -393,6 +404,11 @@ bus_engine_proxy_real_destroy (IBusProxy *proxy)

         engine->keymap = NULL;

     }

+    if (engine->surrounding_text) {

+        g_object_unref (engine->surrounding_text);

+        engine->surrounding_text = NULL;

+    }

+

     IBUS_PROXY_CLASS (bus_engine_proxy_parent_class)->destroy ((IBusProxy *)engine);

 }

@@ -950,6 +966,33 @@ void bus_engine_proxy_property_hide (BusEngineProxy *engine,

                        NULL);

 }

+void bus_engine_proxy_set_surrounding_text (BusEngineProxy *engine,

+                                            IBusText       *text,

+                                            guint           cursor_pos)

+{

+    g_assert (BUS_IS_ENGINE_PROXY (engine));

+    g_assert (text != NULL);

+

+    if (!engine->surrounding_text ||

+        g_strcmp0 (text->text, engine->surrounding_text->text) != 0 ||

+        cursor_pos != engine->surrounding_cursor_pos) {

+        GVariant *variant = ibus_serializable_serialize ((IBusSerializable *)text);

+        if (engine->surrounding_text)

+            g_object_unref (engine->surrounding_text);

+        engine->surrounding_text = (IBusText *) g_object_ref_sink (text);

+        engine->surrounding_cursor_pos = cursor_pos;

+

+        g_dbus_proxy_call ((GDBusProxy *)engine,

+                           "SetSurroundingText",

+                           g_variant_new ("(vu)", variant, cursor_pos),

+                           G_DBUS_CALL_FLAGS_NONE,

+                           -1,

+                           NULL,

+                           NULL,

+                           NULL);

+    }

+}

+

 /* a macro to generate a function to call a nullary D-Bus method. */

 #define DEFINE_FUNCTION(Name, name)                         \

     void                                                    \

diff --git a/bus/engineproxy.h b/bus/engineproxy.h

index 2a82fc6..0680917 100644

--- a/bus/engineproxy.h

+++ b/bus/engineproxy.h

@@ -212,5 +212,16 @@ void             bus_engine_proxy_property_hide     (BusEngineProxy *engine,

  */

 gboolean         bus_engine_proxy_is_enabled        (BusEngineProxy *engine);

+/**

+ * bus_engine_proxy_set_surrounding_text:

+ *

+ * Call "SetSurroundingText" method of an engine asynchronously.

+ */

+void             bus_engine_proxy_set_surrounding_text

+                                                    (BusEngineProxy *engine,

+                                                     IBusText       *text,

+                                                     guint           cursor_pos);

+

+

 G_END_DECLS

 #endif

diff --git a/bus/inputcontext.c b/bus/inputcontext.c

index 32d51e8..20f561c 100644

--- a/bus/inputcontext.c

+++ b/bus/inputcontext.c

@@ -247,6 +247,11 @@ static const gchar introspection_xml[] =

     "    <method name='GetEngine'>"

     "      <arg direction='out' type='v' name='desc' />"

     "    </method>"

+    "    <method name='SetSurroundingText'>"

+    "      <arg direction='in' type='v' name='text' />"

+    "      <arg direction='in' type='u' name='cursor_pos' />"

+    "    </method>"

+

     /* signals */

     "    <signal name='CommitText'>"

     "      <arg type='v' name='text' />"

@@ -961,6 +966,32 @@ _ic_get_engine (BusInputContext       *context,

  * Handle a D-Bus method call whose destination and interface name are both "org.freedesktop.IBus.InputContext"

  */

 static void

+_ic_set_surrounding_text (BusInputContext       *context,

+                          GVariant              *parameters,

+                          GDBusMethodInvocation *invocation)

+{

+    GVariant *variant = NULL;

+    IBusText *text;

+    guint cursor_pos = 0;

+

+    g_variant_get (parameters, "(vu)", &variant, &cursor_pos);

+    text = IBUS_TEXT (ibus_serializable_deserialize (variant));

+    g_variant_unref (variant);

+

+    if ((context->capabilities & IBUS_CAP_SURROUNDING_TEXT) &&

+         context->has_focus && context->enabled && context->engine) {

+        bus_engine_proxy_set_surrounding_text (context->engine,

+                                               text,

+                                               cursor_pos);

+    }

+

+    if (g_object_is_floating (text))

+        g_object_unref (text);

+

+    g_dbus_method_invocation_return_value (invocation, NULL);

+}

+

+static void

 bus_input_context_service_method_call (IBusService            *service,

                                        GDBusConnection        *connection,

                                        const gchar            *sender,

@@ -999,6 +1030,7 @@ bus_input_context_service_method_call (IBusService            *service,

         { "IsEnabled",         _ic_is_enabled },

         { "SetEngine",         _ic_set_engine },

         { "GetEngine",         _ic_get_engine },

+        { "SetSurroundingText", _ic_set_surrounding_text},

     };

     gint i;

@@ -2059,6 +2091,10 @@ bus_input_context_set_engine (BusInputContext *context,

             bus_engine_proxy_set_cursor_location (context->engine, context->x, context->y, context->w, context->h);

         }

     }

+    bus_input_context_emit_signal (context,

+                                   "EngineChanged",

+                                   NULL,

+                                   NULL);

     g_signal_emit (context,

                    context_signals[ENGINE_CHANGED],

                    0);

diff --git a/client/gtk2/ibusimcontext.c b/client/gtk2/ibusimcontext.c

index a4e46cb..d029b5c 100644

--- a/client/gtk2/ibusimcontext.c

+++ b/client/gtk2/ibusimcontext.c

@@ -27,6 +27,7 @@

 #include <gtk/gtk.h>

 #include <gdk/gdkkeysyms.h>

 #include <ibus.h>

+#include <string.h>

 #include "ibusimcontext.h"

 #if !GTK_CHECK_VERSION (2, 91, 0)

@@ -60,7 +61,8 @@ struct _IBusIMContext {

     gboolean         has_focus;

     guint32          time;

-    gint             caps;

+    guint            supported_caps;

+    guint            caps;

 };

 struct _IBusIMContextClass {

@@ -111,11 +113,18 @@ static void     ibus_im_context_set_cursor_location

 static void     ibus_im_context_set_use_preedit

                                             (GtkIMContext           *context,

                                              gboolean               use_preedit);

+static void     ibus_im_context_set_surrounding

+                                            (GtkIMContext  *slave,

+                                             const gchar   *text,

+                                             gint           len,

+                                             gint           cursor_index);

+

 /* static methods*/

 static void     _create_input_context       (IBusIMContext      *context);

 static void     _set_cursor_location_internal

                                             (GtkIMContext       *context);

+static void     _negotiate_capabilities     (IBusIMContext      *context);

 static void     _bus_connected_cb           (IBusBus            *bus,

                                              IBusIMContext      *context);

@@ -129,14 +138,15 @@ static void     _slave_preedit_start_cb     (GtkIMContext       *slave,

                                              IBusIMContext       *context);

 static void     _slave_preedit_end_cb       (GtkIMContext       *slave,

                                              IBusIMContext       *context);

-static void     _slave_retrieve_surrounding_cb

+static gboolean _slave_retrieve_surrounding_cb

                                             (GtkIMContext       *slave,

-                                             IBusIMContext       *context);

-static void     _slave_delete_surrounding_cb

+                                             IBusIMContext      *context);

+static gboolean _slave_delete_surrounding_cb

                                             (GtkIMContext       *slave,

-                                             gint               offset_from_cursor,

-                                             guint              nchars,

-                                             IBusIMContext       *context);

+                                             gint                offset_from_cursor,

+                                             guint               nchars,

+                                             IBusIMContext      *context);

+static void     _request_surrounding_text   (IBusIMContext      *context);

 static void     _create_fake_input_context  (void);

@@ -248,6 +258,17 @@ _process_key_event_done (GObject      *object,

 }

+static void

+_request_surrounding_text (IBusIMContext *context)

+{

+    if (context->enable &&

+        (context->caps & IBUS_CAP_SURROUNDING_TEXT)) {

+        gboolean return_value;

+        g_signal_emit (context, _signal_retrieve_surrounding_id, 0,

+                       &return_value);

+    }

+}

+

 static gint

 _key_snooper_cb (GtkWidget   *widget,

                  GdkEventKey *event,

@@ -334,6 +355,8 @@ _key_snooper_cb (GtkWidget   *widget,

     } while (0);

+    _request_surrounding_text (ibusimcontext);

+

     if (ibusimcontext != NULL) {

         ibusimcontext->time = event->time;

     }

@@ -430,6 +453,7 @@ ibus_im_context_class_init (IBusIMContextClass *class)

     im_context_class->set_client_window = ibus_im_context_set_client_window;

     im_context_class->set_cursor_location = ibus_im_context_set_cursor_location;

     im_context_class->set_use_preedit = ibus_im_context_set_use_preedit;

+    im_context_class->set_surrounding = ibus_im_context_set_surrounding;

     gobject_class->finalize = ibus_im_context_finalize;

     _signal_commit_id =

@@ -577,7 +601,12 @@ ibus_im_context_init (GObject *obj)

     ibusimcontext->ibuscontext = NULL;

     ibusimcontext->has_focus = FALSE;

     ibusimcontext->time = GDK_CURRENT_TIME;

-    ibusimcontext->caps = IBUS_CAP_PREEDIT_TEXT | IBUS_CAP_FOCUS | IBUS_CAP_SURROUNDING_TEXT;

+#ifdef ENABLE_SURROUNDING

+    ibusimcontext->supported_caps = IBUS_CAP_PREEDIT_TEXT | IBUS_CAP_FOCUS | IBUS_CAP_SURROUNDING_TEXT;

+#else

+    ibusimcontext->supported_caps = IBUS_CAP_PREEDIT_TEXT | IBUS_CAP_FOCUS;

+#endif

+    ibusimcontext->caps = ibusimcontext->supported_caps;

     // Create slave im context

@@ -674,6 +703,8 @@ ibus_im_context_filter_keypress (GtkIMContext *context,

         if (ibusimcontext->client_window == NULL && event->window != NULL)

             gtk_im_context_set_client_window ((GtkIMContext *)ibusimcontext, event->window);

+        _request_surrounding_text (ibusimcontext);

+

         if (ibusimcontext != NULL) {

             ibusimcontext->time = event->time;

         }

@@ -768,6 +799,8 @@ ibus_im_context_focus_in (GtkIMContext *context)

                                    (gpointer *) &_focus_im_context);

         _focus_im_context = context;

     }

+

+    _request_surrounding_text (ibusimcontext);

 }

 static void

@@ -925,6 +958,25 @@ ibus_im_context_set_cursor_location (GtkIMContext *context, GdkRectangle *area)

 }

 static void

+_negotiate_capabilities (IBusIMContext *context)

+{

+    IBusEngineDesc *engine;

+

+    engine = ibus_input_context_get_engine (context->ibuscontext);

+    if (engine) {

+        context->caps = context->supported_caps &

+            ibus_engine_desc_get_requires (engine);

+        ibus_input_context_set_capabilities (context->ibuscontext,

+                                             context->caps);

+        IDEBUG ("engine %s: supported caps = %u, engine wants = %u, caps = %u",

+                ibus_engine_desc_get_name (engine)

+                context->supported_caps,

+                ibus_engine_desc_get_requires (engine),

+                context->caps);

+    }

+}

+

+static void

 ibus_im_context_set_use_preedit (GtkIMContext *context, gboolean use_preedit)

 {

     IDEBUG ("%s", __FUNCTION__);

@@ -933,17 +985,50 @@ ibus_im_context_set_use_preedit (GtkIMContext *context, gboolean use_preedit)

     if(ibusimcontext->ibuscontext) {

         if (use_preedit) {

-            ibusimcontext->caps |= IBUS_CAP_PREEDIT_TEXT;

+            ibusimcontext->supported_caps |= IBUS_CAP_PREEDIT_TEXT;

         }

         else {

-            ibusimcontext->caps &= ~IBUS_CAP_PREEDIT_TEXT;

+            ibusimcontext->supported_caps &= ~IBUS_CAP_PREEDIT_TEXT;

         }

-        ibus_input_context_set_capabilities (ibusimcontext->ibuscontext, ibusimcontext->caps);

+        _negotiate_capabilities (ibusimcontext);

     }

     gtk_im_context_set_use_preedit (ibusimcontext->slave, use_preedit);

 }

 static void

+ibus_im_context_set_surrounding (GtkIMContext  *context,

+                                 const gchar   *text,

+                                 gint           len,

+                                 gint           cursor_index)

+{

+    g_return_if_fail (context != NULL);

+    g_return_if_fail (IBUS_IS_IM_CONTEXT (context));

+    g_return_if_fail (text != NULL);

+    g_return_if_fail (strlen (text) >= len);

+    g_return_if_fail (0 <= cursor_index && cursor_index <= len);

+

+    IBusIMContext *ibusimcontext = IBUS_IM_CONTEXT (context);

+

+    if (ibusimcontext->enable && ibusimcontext->ibuscontext) {

+        IBusText *ibustext;

+        guint cursor_pos;

+        gchar *p;

+

+        p = g_strndup (text, len);

+        cursor_pos = g_utf8_strlen (p, cursor_index);

+        ibustext = ibus_text_new_from_string (p);

+        g_free (p);

+        ibus_input_context_set_surrounding_text (ibusimcontext->ibuscontext,

+                                                 ibustext,

+                                                 cursor_pos);

+    }

+    gtk_im_context_set_surrounding (ibusimcontext->slave,

+                                    text,

+                                    len,

+                                    cursor_index);

+}

+

+static void

 _bus_connected_cb (IBusBus          *bus,

                    IBusIMContext    *ibusimcontext)

 {

@@ -962,6 +1047,8 @@ _ibus_context_commit_text_cb (IBusInputContext *ibuscontext,

     IDEBUG ("%s", __FUNCTION__);

     g_signal_emit (ibusimcontext, _signal_commit_id, 0, text->text);

+

+    _request_surrounding_text (ibusimcontext);

 }

 static gboolean

@@ -1256,6 +1343,8 @@ _ibus_context_show_preedit_text_cb (IBusInputContext   *ibuscontext,

     ibusimcontext->preedit_visible = TRUE;

     g_signal_emit (ibusimcontext, _signal_preedit_start_id, 0);

     g_signal_emit (ibusimcontext, _signal_preedit_changed_id, 0);

+

+    _request_surrounding_text (ibusimcontext);

 }

 static void

@@ -1321,6 +1410,14 @@ _ibus_context_destroy_cb (IBusInputContext *ibuscontext,

 }

 static void

+_ibus_context_engine_changed_cb (IBusInputContext *ibuscontext,

+                                 IBusIMContext    *ibusimcontext)

+{

+    IDEBUG ("%s", __FUNCTION__);

+    _negotiate_capabilities (ibusimcontext);

+}

+

+static void

 _create_input_context (IBusIMContext *ibusimcontext)

 {

     IDEBUG ("%s", __FUNCTION__);

@@ -1363,6 +1460,10 @@ _create_input_context (IBusIMContext *ibusimcontext)

                       "disabled",

                       G_CALLBACK (_ibus_context_disabled_cb),

                       ibusimcontext);

+    g_signal_connect (ibusimcontext->ibuscontext,

+                      "engine-changed",

+                      G_CALLBACK (_ibus_context_engine_changed_cb),

+                      ibusimcontext);

     g_signal_connect (ibusimcontext->ibuscontext, "destroy",

                       G_CALLBACK (_ibus_context_destroy_cb),

                       ibusimcontext);

@@ -1419,17 +1520,21 @@ _slave_preedit_end_cb (GtkIMContext  *slave,

     g_signal_emit (ibusimcontext, _signal_preedit_end_id, 0);

 }

-static void

+static gboolean

 _slave_retrieve_surrounding_cb (GtkIMContext  *slave,

                                 IBusIMContext *ibusimcontext)

 {

+    gboolean return_value;

+

     if (ibusimcontext->enable && ibusimcontext->ibuscontext) {

-        return;

+        return FALSE;

     }

-    g_signal_emit (ibusimcontext, _signal_retrieve_surrounding_id, 0);

+    g_signal_emit (ibusimcontext, _signal_retrieve_surrounding_id, 0,

+                   &return_value);

+    return return_value;

 }

-static void

+static gboolean

 _slave_delete_surrounding_cb (GtkIMContext  *slave,

                               gint           offset_from_cursor,

                               guint          nchars,

@@ -1438,9 +1543,10 @@ _slave_delete_surrounding_cb (GtkIMContext  *slave,

     gboolean return_value;

     if (ibusimcontext->enable && ibusimcontext->ibuscontext) {

-        return;

+        return FALSE;

     }

     g_signal_emit (ibusimcontext, _signal_delete_surrounding_id, 0, offset_from_cursor, nchars, &return_value);

+    return return_value;

 }

 #ifdef OS_CHROMEOS

diff --git a/configure.ac b/configure.ac

index 81efe81..e5fe925 100644

--- a/configure.ac

+++ b/configure.ac

@@ -364,6 +364,19 @@ AC_ARG_WITH(sync-mode-apps,

 AC_DEFINE_UNQUOTED(SYNC_MODE_APPS, "$SYNC_MODE_APPS",

     [Enbale sync mode in those applications])

+# option for enable surrounding-text

+AC_ARG_ENABLE(surrounding-text,

+    AS_HELP_STRING([--enable-surrounding-text],

+        [Enable surrounding-text support]),

+    [enable_surrounding_text=$enableval],

+    [enable_surrounding_text=no]

+)

+if test x"$enable_surrounding_text" = x"yes"; then

+    AC_DEFINE(ENABLE_SURROUNDING, TRUE, [Enable surrounding-text support])

+else

+    enable_surrounding_text="no (disabled, use --enable-surrounding-text to enable)"

+fi

+

 # check iso-codes

 PKG_CHECK_MODULES(ISOCODES, [

     iso-codes

@@ -435,5 +448,6 @@ Build options:

   Enable key snooper        $enable_key_snooper

   Sync mode regexes         "$SYNC_MODE_APPS"

   No snooper regexes        "$NO_SNOOPER_APPS"

+  Enable surrounding-text   $enable_surrounding_text

 ])

diff --git a/ibus/engine.py b/ibus/engine.py

index b1df2fe..ec42fa4 100644

--- a/ibus/engine.py

+++ b/ibus/engine.py

@@ -46,6 +46,9 @@ class EngineBase(object.Object):

     def set_cursor_location(self, x, y, w, h):

         pass

+    def set_surrounding_text(self, text, cursor_index):

+        pass

+

     def set_capabilities(self, cap):

         pass

@@ -163,6 +166,9 @@ class EngineProxy(interface.IEngine):

     def SetCursorLocation(self, x, y, w, h):

         return self.__engine.set_cursor_location(x, y, w, h)

+    def SetSurroundingText(self, text, cursor_index):

+        return self.__engine.set_surrounding_text(text, cursor_index)

+

     def SetCapabilities(self, caps):

         return self.__engine.set_capabilities(caps)

diff --git a/ibus/interface/iengine.py b/ibus/interface/iengine.py

index 2386c0f..5db2012 100644

--- a/ibus/interface/iengine.py

+++ b/ibus/interface/iengine.py

@@ -50,6 +50,9 @@ class IEngine(dbus.service.Object):

     @method(in_signature="iiii")

     def SetCursorLocation(self, x, y, w, h): pass

+    @method(in_signature="vu")

+    def SetSurroundingText(self, text, cursor_index): pass

+

     @method(in_signature="u")

     def SetCapabilities(self, cap): pass

diff --git a/ibus/interface/iinputcontext.py b/ibus/interface/iinputcontext.py

index 89f6dbd..bb25c5a 100644

--- a/ibus/interface/iinputcontext.py

+++ b/ibus/interface/iinputcontext.py

@@ -49,6 +49,9 @@ class IInputContext(dbus.service.Object):

     @method(in_signature="iiii")

     def SetCursorLocation(self, x, y, w, h): pass

+    @method(in_signature="vu")

+    def SetSurroundingText(self, text, cursor_index): pass

+

     @method()

     def FocusIn(self): pass

@@ -137,4 +140,6 @@ class IInputContext(dbus.service.Object):

     @signal(signature="v")

     def UpdateProperty(self, prop): pass

+    @signal()

+    def EngineChanged(self): pass

diff --git a/src/ibusengine.c b/src/ibusengine.c

index 519d7ca..fc129a2 100644

--- a/src/ibusengine.c

+++ b/src/ibusengine.c

@@ -45,6 +45,7 @@ enum {

     PROPERTY_SHOW,

     PROPERTY_HIDE,

     CANDIDATE_CLICKED,

+    SET_SURROUNDING_TEXT,

     LAST_SIGNAL,

 };

@@ -58,10 +59,15 @@ enum {

 struct _IBusEnginePrivate {

     gchar *engine_name;

     GDBusConnection *connection;

+

+    IBusText *surrounding_text;

+    guint surrounding_cursor_pos;

 };

 static guint            engine_signals[LAST_SIGNAL] = { 0 };

+static IBusText *text_empty = NULL;

+

 /* functions prototype */

 static void      ibus_engine_destroy         (IBusEngine         *engine);

 static void      ibus_engine_set_property    (IBusEngine         *engine,

@@ -135,6 +141,10 @@ static void      ibus_engine_property_show   (IBusEngine         *engine,

                                               const gchar        *prop_name);

 static void      ibus_engine_property_hide   (IBusEngine         *engine,

                                               const gchar        *prop_name);

+static void      ibus_engine_set_surrounding_text

+                                            (IBusEngine         *engine,

+                                             IBusText           *text,

+                                             guint               cursor_pos);

 static void      ibus_engine_emit_signal     (IBusEngine         *engine,

                                               const gchar        *signal_name,

                                               GVariant           *parameters);

@@ -185,6 +195,10 @@ static const gchar introspection_xml[] =

     "    <method name='PageDown' />"

     "    <method name='CursorUp' />"

     "    <method name='CursorDown' />"

+    "    <method name='SetSurroundingText'>"

+    "      <arg direction='in'  type='v' name='text' />"

+    "      <arg direction='in'  type='u' name='cursor_pos' />"

+    "    </method>"

     /* FIXME signals */

     "    <signal name='CommitText'>"

     "      <arg type='v' name='text' />"

@@ -250,6 +264,7 @@ ibus_engine_class_init (IBusEngineClass *class)

     class->property_hide        = ibus_engine_property_hide;

     class->set_cursor_location  = ibus_engine_set_cursor_location;

     class->set_capabilities     = ibus_engine_set_capabilities;

+    class->set_surrounding_text = ibus_engine_set_surrounding_text;

     /* install properties */

     /**

@@ -616,12 +631,39 @@ ibus_engine_class_init (IBusEngineClass *class)

             G_TYPE_STRING);

     g_type_class_add_private (class, sizeof (IBusEnginePrivate));

+

+    /**

+     * IBusEngine::set-surrounding-text:

+     * @engine: An IBusEngine.

+     *

+     * Emitted when a surrounding text is set.

+     * Implement the member function set_surrounding_text() in extended class to receive this signal.

+     *

+     * <note><para>Argument @user_data is ignored in this function.</para></note>

+     */

+    engine_signals[SET_SURROUNDING_TEXT] =

+        g_signal_new (I_("set-surrounding-text"),

+            G_TYPE_FROM_CLASS (gobject_class),

+            G_SIGNAL_RUN_LAST,

+            G_STRUCT_OFFSET (IBusEngineClass, set_surrounding_text),

+            NULL, NULL,

+            _ibus_marshal_VOID__OBJECT_UINT,

+            G_TYPE_NONE,

+            2,

+            G_TYPE_OBJECT,

+            G_TYPE_UINT);

+

+    text_empty = ibus_text_new_from_static_string ("");

+    g_object_ref_sink (text_empty);

 }

 static void

 ibus_engine_init (IBusEngine *engine)

 {

     engine->priv = IBUS_ENGINE_GET_PRIVATE (engine);

+

+    engine->priv->surrounding_text = g_object_ref_sink (text_empty);

+    engine->priv->surrounding_cursor_pos = 0;

 }

 static void

@@ -630,6 +672,11 @@ ibus_engine_destroy (IBusEngine *engine)

     g_free (engine->priv->engine_name);

     engine->priv->engine_name = NULL;

+    if (engine->priv->surrounding_text) {

+        g_object_unref (engine->priv->surrounding_text);

+        engine->priv->surrounding_text = NULL;

+    }

+

     IBUS_OBJECT_CLASS(ibus_engine_parent_class)->destroy (IBUS_OBJECT (engine));

 }

@@ -801,6 +848,25 @@ ibus_engine_service_method_call (IBusService           *service,

         return;

     }

+    if (g_strcmp0 (method_name, "SetSurroundingText") == 0) {

+        GVariant *variant = NULL;

+        IBusText *text;

+        guint cursor_pos;