| // Copyright 2013 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "ui/base/ime/composition_text_util_pango.h" |
| |
| #include <pango/pango-attributes.h> |
| |
| #include "base/basictypes.h" |
| #include "base/i18n/char_iterator.h" |
| #include "base/strings/string16.h" |
| #include "base/strings/utf_string_conversions.h" |
| #include "ui/base/ime/composition_text.h" |
| |
| namespace ui { |
| |
| void ExtractCompositionTextFromGtkPreedit(const gchar* utf8_text, |
| PangoAttrList* attrs, |
| int cursor_position, |
| CompositionText* composition) { |
| composition->Clear(); |
| composition->text = base::UTF8ToUTF16(utf8_text); |
| |
| if (composition->text.empty()) |
| return; |
| |
| // Gtk/Pango uses character index for cursor position and byte index for |
| // attribute range, but we use char16 offset for them. So we need to do |
| // conversion here. |
| std::vector<size_t> char16_offsets; |
| size_t length = composition->text.length(); |
| base::i18n::UTF16CharIterator char_iterator(&composition->text); |
| do { |
| char16_offsets.push_back(char_iterator.array_pos()); |
| } while (char_iterator.Advance()); |
| |
| // The text length in Unicode characters. |
| int char_length = static_cast<int>(char16_offsets.size()); |
| // Make sure we can convert the value of |char_length| as well. |
| char16_offsets.push_back(length); |
| |
| size_t cursor_offset = |
| char16_offsets[std::max(0, std::min(char_length, cursor_position))]; |
| |
| composition->selection = gfx::Range(cursor_offset); |
| |
| if (attrs) { |
| int utf8_length = strlen(utf8_text); |
| PangoAttrIterator* iter = pango_attr_list_get_iterator(attrs); |
| |
| // We only care about underline and background attributes and convert |
| // background attribute into selection if possible. |
| do { |
| gint start, end; |
| pango_attr_iterator_range(iter, &start, &end); |
| |
| start = std::min(start, utf8_length); |
| end = std::min(end, utf8_length); |
| if (start >= end) |
| continue; |
| |
| start = g_utf8_pointer_to_offset(utf8_text, utf8_text + start); |
| end = g_utf8_pointer_to_offset(utf8_text, utf8_text + end); |
| |
| // Double check, in case |utf8_text| is not a valid utf-8 string. |
| start = std::min(start, char_length); |
| end = std::min(end, char_length); |
| if (start >= end) |
| continue; |
| |
| PangoAttribute* background_attr = |
| pango_attr_iterator_get(iter, PANGO_ATTR_BACKGROUND); |
| PangoAttribute* underline_attr = |
| pango_attr_iterator_get(iter, PANGO_ATTR_UNDERLINE); |
| |
| if (background_attr || underline_attr) { |
| // Use a black thin underline by default. |
| CompositionUnderline underline(char16_offsets[start], |
| char16_offsets[end], |
| SK_ColorBLACK, |
| false, |
| SK_ColorTRANSPARENT); |
| |
| // Always use thick underline for a range with background color, which |
| // is usually the selection range. |
| if (background_attr) { |
| underline.thick = true; |
| // If the cursor is at start or end of this underline, then we treat |
| // it as the selection range as well, but make sure to set the cursor |
| // position to the selection end. |
| if (underline.start_offset == cursor_offset) { |
| composition->selection.set_start(underline.end_offset); |
| composition->selection.set_end(cursor_offset); |
| } else if (underline.end_offset == cursor_offset) { |
| composition->selection.set_start(underline.start_offset); |
| composition->selection.set_end(cursor_offset); |
| } |
| } |
| if (underline_attr) { |
| int type = reinterpret_cast<PangoAttrInt*>(underline_attr)->value; |
| if (type == PANGO_UNDERLINE_DOUBLE) |
| underline.thick = true; |
| else if (type == PANGO_UNDERLINE_ERROR) |
| underline.color = SK_ColorRED; |
| } |
| composition->underlines.push_back(underline); |
| } |
| } while (pango_attr_iterator_next(iter)); |
| pango_attr_iterator_destroy(iter); |
| } |
| |
| // Use a black thin underline by default. |
| if (composition->underlines.empty()) { |
| composition->underlines.push_back(CompositionUnderline( |
| 0, length, SK_ColorBLACK, false, SK_ColorTRANSPARENT)); |
| } |
| } |
| |
| } // namespace ui |