Move BiDiLineIterator to base/i18n/ directory.

BUG=23581
TEST=trybots

Review URL: http://codereview.chromium.org/6249007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@71884 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 109 insertions, 0 deletions

diff --git a/base/base.gyp b/base/base.gyp
index 6dc450c..fbef42b 100644
--- a/base/base.gyp
+++ b/base/base.gyp
@@ -31,6 +31,8 @@
         'base',
       ],
       'sources': [
+	'i18n/bidi_line_iterator.cc',
+	'i18n/bidi_line_iterator.h',
         'i18n/break_iterator.cc',
         'i18n/break_iterator.h',
         'i18n/char_iterator.cc',
diff --git a/base/i18n/bidi_line_iterator.cc b/base/i18n/bidi_line_iterator.cc
new file mode 100644
index 0000000..3222a3a
--- /dev/null
+++ b/base/i18n/bidi_line_iterator.cc
@@ -0,0 +1,60 @@
+// Copyright (c) 2011 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 "base/i18n/bidi_line_iterator.h"
+
+#include "base/logging.h"
+
+namespace base {
+namespace i18n {
+
+BiDiLineIterator::BiDiLineIterator() : bidi_(NULL) {
+}
+
+BiDiLineIterator::~BiDiLineIterator() {
+  if (bidi_) {
+    ubidi_close(bidi_);
+    bidi_ = NULL;
+  }
+}
+
+bool BiDiLineIterator::Open(const string16& text,
+                            bool right_to_left,
+                            bool url) {
+  DCHECK(bidi_ == NULL);
+  UErrorCode error = U_ZERO_ERROR;
+  bidi_ = ubidi_openSized(static_cast<int>(text.length()), 0, &error);
+  if (U_FAILURE(error))
+    return false;
+  if (right_to_left && url)
+    ubidi_setReorderingMode(bidi_, UBIDI_REORDER_RUNS_ONLY);
+  ubidi_setPara(bidi_, text.data(), static_cast<int>(text.length()),
+                right_to_left ? UBIDI_DEFAULT_RTL : UBIDI_DEFAULT_LTR,
+                NULL, &error);
+  return U_SUCCESS(error) ? true : false;
+}
+
+int BiDiLineIterator::CountRuns() {
+  DCHECK(bidi_ != NULL);
+  UErrorCode error = U_ZERO_ERROR;
+  const int runs = ubidi_countRuns(bidi_, &error);
+  return U_SUCCESS(error) ? runs : 0;
+}
+
+UBiDiDirection BiDiLineIterator::GetVisualRun(int index,
+                                              int* start,
+                                              int* length) {
+  DCHECK(bidi_ != NULL);
+  return ubidi_getVisualRun(bidi_, index, start, length);
+}
+
+void BiDiLineIterator::GetLogicalRun(int start,
+                                     int* end,
+                                     UBiDiLevel* level) {
+  DCHECK(bidi_ != NULL);
+  ubidi_getLogicalRun(bidi_, start, end, level);
+}
+
+}  // namespace i18n
+}  // namespace base
diff --git a/base/i18n/bidi_line_iterator.h b/base/i18n/bidi_line_iterator.h
new file mode 100644
index 0000000..5fff6a3
--- /dev/null
+++ b/base/i18n/bidi_line_iterator.h
@@ -0,0 +1,47 @@
+// Copyright (c) 2011 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.
+
+#ifndef BASE_I18N_BIDI_LINE_ITERATOR_H_
+#define BASE_I18N_BIDI_LINE_ITERATOR_H_
+#pragma once
+
+#include "unicode/ubidi.h"
+
+#include "base/basictypes.h"
+#include "base/string16.h"
+
+namespace base {
+namespace i18n {
+
+// A simple wrapper class for the bidirectional iterator of ICU.
+// This class uses the bidirectional iterator of ICU to split a line of
+// bidirectional texts into visual runs in its display order.
+class BiDiLineIterator {
+ public:
+  BiDiLineIterator();
+  ~BiDiLineIterator();
+
+  // Initializes the bidirectional iterator with the specified text.  Returns
+  // whether initialization succeeded.
+  bool Open(const string16& text, bool right_to_left, bool url);
+
+  // Returns the number of visual runs in the text, or zero on error.
+  int CountRuns();
+
+  // Gets the logical offset, length, and direction of the specified visual run.
+  UBiDiDirection GetVisualRun(int index, int* start, int* length);
+
+  // Given a start position, figure out where the run ends (and the BiDiLevel).
+  void GetLogicalRun(int start, int* end, UBiDiLevel* level);
+
+ private:
+  UBiDi* bidi_;
+
+  DISALLOW_COPY_AND_ASSIGN(BiDiLineIterator);
+};
+
+}  // namespace i18n
+}  // namespace base
+
+#endif  // BASE_I18N_BIDI_LINE_ITERATOR_H_