From ed0a6448c6fcb38ce1b36e49345df343c4174596 Mon Sep 17 00:00:00 2001
From: Daiki Ueno <ueno@unixuser.org>
Date: Mon, 16 Dec 2013 12:55:13 +0900
Subject: [PATCH] Report cursor width when editing input

---
 libkkc/context.vala |  9 +++++++++
 libkkc/state.vala   | 36 ++++++++++++++++++++++++++++++++++--
 2 files changed, 43 insertions(+), 2 deletions(-)

diff --git a/libkkc/context.vala b/libkkc/context.vala
index 98bfed6..69db253 100644
--- a/libkkc/context.vala
+++ b/libkkc/context.vala
@@ -70,6 +70,15 @@ namespace Kkc {
             }
         }
 
+        /**
+         * Current cursor width in input string.
+         */
+        public uint input_cursor_width {
+            get {
+                return state.input_cursor_width;
+            }
+        }
+
         State state;
         Gee.Map<Type, StateHandler> handlers =
             new HashMap<Type, StateHandler> ();
diff --git a/libkkc/state.vala b/libkkc/state.vala
index 4014a89..9d47321 100644
--- a/libkkc/state.vala
+++ b/libkkc/state.vala
@@ -109,10 +109,42 @@ namespace Kkc {
         internal int input_characters_cursor_pos = -1;
 
         internal int input_cursor_pos {
+            get {
+                if (input_characters_cursor_pos >= 0) {
+                    var index = 0;
+                    var offset = 0;
+                    for (; index < input_characters_cursor_pos; index++) {
+                        offset += input_characters[index].output.char_count ();
+                    }
+                    // Hack for Kana typing rule: add the length of
+                    // unfinished Kana input.  Suppose the following
+                    // input when moving cursor in the initial state:
+                    //
+                    //   F|F|FFFFF (F = finished characters, | = cursor)
+                    //
+                    // If user types a finished character (e.g. A, I):
+                    //
+                    //   FX|F|FFFFF
+                    // 
+                    // On the other hand, if user types an unfinished
+                    // character (e.g. KA, CHI, which may be followed
+                    // by sonant marks):
+                    //
+                    //   F|X|FFFFFF
+                    //
+                    // For consistency, move the cursor by the width
+                    // of the unfisnished character.
+                    offset += rom_kana_converter.pending_output.char_count ();
+                    return offset;
+                }
+                return input_characters_cursor_pos;
+            }
+        }
+
+        internal uint input_cursor_width {
             get {
                 if (input_characters_cursor_pos >= 0)
-                    return input_characters_cursor_pos +
-                        rom_kana_converter.pending_output.char_count ();
+                    return input_characters[input_characters_cursor_pos].output.char_count ();
                 return input_characters_cursor_pos;
             }
         }