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Issue 854713003: More old files deletion. (Closed) Base URL: https://github.com/domokit/mojo.git@master
Patch Set: Fix tryjobs? Created 5 years, 11 months ago
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1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 //
5 // This file implements utility functions for eliding and formatting UI text.
6 //
7 // Note that several of the functions declared in text_elider.h are implemented
8 // in this file using helper classes in an unnamed namespace.
9
10 #include "ui/gfx/text_elider.h"
11
12 #include <string>
13 #include <vector>
14
15 #include "base/files/file_path.h"
16 #include "base/i18n/break_iterator.h"
17 #include "base/i18n/char_iterator.h"
18 #include "base/i18n/rtl.h"
19 #include "base/memory/scoped_ptr.h"
20 #include "base/numerics/safe_conversions.h"
21 #include "base/strings/string_split.h"
22 #include "base/strings/string_util.h"
23 #include "base/strings/sys_string_conversions.h"
24 #include "base/strings/utf_string_conversions.h"
25 #include "third_party/icu/source/common/unicode/rbbi.h"
26 #include "third_party/icu/source/common/unicode/uloc.h"
27 #include "ui/gfx/font_list.h"
28 #include "ui/gfx/render_text.h"
29 #include "ui/gfx/text_utils.h"
30
31 using base::ASCIIToUTF16;
32 using base::UTF8ToUTF16;
33 using base::WideToUTF16;
34
35 namespace gfx {
36
37 namespace {
38
39 #if defined(OS_ANDROID) || defined(OS_IOS)
40 // The returned string will have at least one character besides the ellipsis
41 // on either side of '@'; if that's impossible, a single ellipsis is returned.
42 // If possible, only the username is elided. Otherwise, the domain is elided
43 // in the middle, splitting available width equally with the elided username.
44 // If the username is short enough that it doesn't need half the available
45 // width, the elided domain will occupy that extra width.
46 base::string16 ElideEmail(const base::string16& email,
47 const FontList& font_list,
48 float available_pixel_width) {
49 if (GetStringWidthF(email, font_list) <= available_pixel_width)
50 return email;
51
52 // Split the email into its local-part (username) and domain-part. The email
53 // spec allows for @ symbols in the username under some special requirements,
54 // but not in the domain part, so splitting at the last @ symbol is safe.
55 const size_t split_index = email.find_last_of('@');
56 DCHECK_NE(split_index, base::string16::npos);
57 base::string16 username = email.substr(0, split_index);
58 base::string16 domain = email.substr(split_index + 1);
59 DCHECK(!username.empty());
60 DCHECK(!domain.empty());
61
62 // Subtract the @ symbol from the available width as it is mandatory.
63 const base::string16 kAtSignUTF16 = ASCIIToUTF16("@");
64 available_pixel_width -= GetStringWidthF(kAtSignUTF16, font_list);
65
66 // Check whether eliding the domain is necessary: if eliding the username
67 // is sufficient, the domain will not be elided.
68 const float full_username_width = GetStringWidthF(username, font_list);
69 const float available_domain_width =
70 available_pixel_width -
71 std::min(full_username_width,
72 GetStringWidthF(username.substr(0, 1) + kEllipsisUTF16,
73 font_list));
74 if (GetStringWidthF(domain, font_list) > available_domain_width) {
75 // Elide the domain so that it only takes half of the available width.
76 // Should the username not need all the width available in its half, the
77 // domain will occupy the leftover width.
78 // If |desired_domain_width| is greater than |available_domain_width|: the
79 // minimal username elision allowed by the specifications will not fit; thus
80 // |desired_domain_width| must be <= |available_domain_width| at all cost.
81 const float desired_domain_width =
82 std::min(available_domain_width,
83 std::max(available_pixel_width - full_username_width,
84 available_pixel_width / 2));
85 domain = ElideText(domain, font_list, desired_domain_width, ELIDE_MIDDLE);
86 // Failing to elide the domain such that at least one character remains
87 // (other than the ellipsis itself) remains: return a single ellipsis.
88 if (domain.length() <= 1U)
89 return base::string16(kEllipsisUTF16);
90 }
91
92 // Fit the username in the remaining width (at this point the elided username
93 // is guaranteed to fit with at least one character remaining given all the
94 // precautions taken earlier).
95 available_pixel_width -= GetStringWidthF(domain, font_list);
96 username = ElideText(username, font_list, available_pixel_width, ELIDE_TAIL);
97 return username + kAtSignUTF16 + domain;
98 }
99 #endif
100
101 } // namespace
102
103 // U+2026 in utf8
104 const char kEllipsis[] = "\xE2\x80\xA6";
105 const base::char16 kEllipsisUTF16[] = { 0x2026, 0 };
106 const base::char16 kForwardSlash = '/';
107
108 StringSlicer::StringSlicer(const base::string16& text,
109 const base::string16& ellipsis,
110 bool elide_in_middle,
111 bool elide_at_beginning)
112 : text_(text),
113 ellipsis_(ellipsis),
114 elide_in_middle_(elide_in_middle),
115 elide_at_beginning_(elide_at_beginning) {
116 }
117
118 base::string16 StringSlicer::CutString(size_t length, bool insert_ellipsis) {
119 const base::string16 ellipsis_text = insert_ellipsis ? ellipsis_
120 : base::string16();
121
122 if (elide_at_beginning_)
123 return ellipsis_text +
124 text_.substr(FindValidBoundaryBefore(text_.length() - length));
125
126 if (!elide_in_middle_)
127 return text_.substr(0, FindValidBoundaryBefore(length)) + ellipsis_text;
128
129 // We put the extra character, if any, before the cut.
130 const size_t half_length = length / 2;
131 const size_t prefix_length = FindValidBoundaryBefore(length - half_length);
132 const size_t suffix_start_guess = text_.length() - half_length;
133 const size_t suffix_start = FindValidBoundaryAfter(suffix_start_guess);
134 const size_t suffix_length =
135 half_length - (suffix_start_guess - suffix_start);
136 return text_.substr(0, prefix_length) + ellipsis_text +
137 text_.substr(suffix_start, suffix_length);
138 }
139
140 size_t StringSlicer::FindValidBoundaryBefore(size_t index) const {
141 DCHECK_LE(index, text_.length());
142 if (index != text_.length())
143 U16_SET_CP_START(text_.data(), 0, index);
144 return index;
145 }
146
147 size_t StringSlicer::FindValidBoundaryAfter(size_t index) const {
148 DCHECK_LE(index, text_.length());
149 if (index == text_.length())
150 return index;
151
152 int32_t text_index = base::checked_cast<int32_t>(index);
153 int32_t text_length = base::checked_cast<int32_t>(text_.length());
154 U16_SET_CP_LIMIT(text_.data(), 0, text_index, text_length);
155 return static_cast<size_t>(text_index);
156 }
157
158 base::string16 ElideFilename(const base::FilePath& filename,
159 const FontList& font_list,
160 float available_pixel_width) {
161 #if defined(OS_WIN)
162 base::string16 filename_utf16 = filename.value();
163 base::string16 extension = filename.Extension();
164 base::string16 rootname = filename.BaseName().RemoveExtension().value();
165 #elif defined(OS_POSIX)
166 base::string16 filename_utf16 = WideToUTF16(base::SysNativeMBToWide(
167 filename.value()));
168 base::string16 extension = WideToUTF16(base::SysNativeMBToWide(
169 filename.Extension()));
170 base::string16 rootname = WideToUTF16(base::SysNativeMBToWide(
171 filename.BaseName().RemoveExtension().value()));
172 #endif
173
174 const float full_width = GetStringWidthF(filename_utf16, font_list);
175 if (full_width <= available_pixel_width)
176 return base::i18n::GetDisplayStringInLTRDirectionality(filename_utf16);
177
178 if (rootname.empty() || extension.empty()) {
179 const base::string16 elided_name =
180 ElideText(filename_utf16, font_list, available_pixel_width, ELIDE_TAIL);
181 return base::i18n::GetDisplayStringInLTRDirectionality(elided_name);
182 }
183
184 const float ext_width = GetStringWidthF(extension, font_list);
185 const float root_width = GetStringWidthF(rootname, font_list);
186
187 // We may have trimmed the path.
188 if (root_width + ext_width <= available_pixel_width) {
189 const base::string16 elided_name = rootname + extension;
190 return base::i18n::GetDisplayStringInLTRDirectionality(elided_name);
191 }
192
193 if (ext_width >= available_pixel_width) {
194 const base::string16 elided_name = ElideText(
195 rootname + extension, font_list, available_pixel_width, ELIDE_MIDDLE);
196 return base::i18n::GetDisplayStringInLTRDirectionality(elided_name);
197 }
198
199 float available_root_width = available_pixel_width - ext_width;
200 base::string16 elided_name =
201 ElideText(rootname, font_list, available_root_width, ELIDE_TAIL);
202 elided_name += extension;
203 return base::i18n::GetDisplayStringInLTRDirectionality(elided_name);
204 }
205
206 base::string16 ElideText(const base::string16& text,
207 const FontList& font_list,
208 float available_pixel_width,
209 ElideBehavior behavior) {
210 #if !defined(OS_ANDROID) && !defined(OS_IOS)
211 DCHECK_NE(behavior, FADE_TAIL);
212 scoped_ptr<RenderText> render_text(RenderText::CreateInstance());
213 render_text->SetCursorEnabled(false);
214 // Do not bother accurately sizing strings over 5000 characters here, for
215 // performance purposes. This matches the behavior of Canvas::SizeStringFloat.
216 render_text->set_truncate_length(5000);
217 render_text->SetFontList(font_list);
218 available_pixel_width = std::ceil(available_pixel_width);
219 render_text->SetDisplayRect(gfx::Rect(gfx::Size(available_pixel_width, 1)));
220 render_text->SetElideBehavior(behavior);
221 render_text->SetText(text);
222 return render_text->layout_text();
223 #else
224 DCHECK_NE(behavior, FADE_TAIL);
225 if (text.empty() || behavior == FADE_TAIL || behavior == NO_ELIDE ||
226 GetStringWidthF(text, font_list) <= available_pixel_width) {
227 return text;
228 }
229 if (behavior == ELIDE_EMAIL)
230 return ElideEmail(text, font_list, available_pixel_width);
231
232 const bool elide_in_middle = (behavior == ELIDE_MIDDLE);
233 const bool elide_at_beginning = (behavior == ELIDE_HEAD);
234 const bool insert_ellipsis = (behavior != TRUNCATE);
235 const base::string16 ellipsis = base::string16(kEllipsisUTF16);
236 StringSlicer slicer(text, ellipsis, elide_in_middle, elide_at_beginning);
237
238 if (insert_ellipsis &&
239 GetStringWidthF(ellipsis, font_list) > available_pixel_width)
240 return base::string16();
241
242 // Use binary search to compute the elided text.
243 size_t lo = 0;
244 size_t hi = text.length() - 1;
245 size_t guess;
246 for (guess = (lo + hi) / 2; lo <= hi; guess = (lo + hi) / 2) {
247 // We check the width of the whole desired string at once to ensure we
248 // handle kerning/ligatures/etc. correctly.
249 // TODO(skanuj) : Handle directionality of ellipsis based on adjacent
250 // characters. See crbug.com/327963.
251 const base::string16 cut = slicer.CutString(guess, insert_ellipsis);
252 const float guess_width = GetStringWidthF(cut, font_list);
253 if (guess_width == available_pixel_width)
254 break;
255 if (guess_width > available_pixel_width) {
256 hi = guess - 1;
257 // Move back on the loop terminating condition when the guess is too wide.
258 if (hi < lo)
259 lo = hi;
260 } else {
261 lo = guess + 1;
262 }
263 }
264
265 return slicer.CutString(guess, insert_ellipsis);
266 #endif
267 }
268
269 bool ElideString(const base::string16& input,
270 int max_len,
271 base::string16* output) {
272 DCHECK_GE(max_len, 0);
273 if (static_cast<int>(input.length()) <= max_len) {
274 output->assign(input);
275 return false;
276 }
277
278 switch (max_len) {
279 case 0:
280 output->clear();
281 break;
282 case 1:
283 output->assign(input.substr(0, 1));
284 break;
285 case 2:
286 output->assign(input.substr(0, 2));
287 break;
288 case 3:
289 output->assign(input.substr(0, 1) + ASCIIToUTF16(".") +
290 input.substr(input.length() - 1));
291 break;
292 case 4:
293 output->assign(input.substr(0, 1) + ASCIIToUTF16("..") +
294 input.substr(input.length() - 1));
295 break;
296 default: {
297 int rstr_len = (max_len - 3) / 2;
298 int lstr_len = rstr_len + ((max_len - 3) % 2);
299 output->assign(input.substr(0, lstr_len) + ASCIIToUTF16("...") +
300 input.substr(input.length() - rstr_len));
301 break;
302 }
303 }
304
305 return true;
306 }
307
308 namespace {
309
310 // Internal class used to track progress of a rectangular string elide
311 // operation. Exists so the top-level ElideRectangleString() function
312 // can be broken into smaller methods sharing this state.
313 class RectangleString {
314 public:
315 RectangleString(size_t max_rows, size_t max_cols,
316 bool strict, base::string16 *output)
317 : max_rows_(max_rows),
318 max_cols_(max_cols),
319 current_row_(0),
320 current_col_(0),
321 strict_(strict),
322 suppressed_(false),
323 output_(output) {}
324
325 // Perform deferred initializations following creation. Must be called
326 // before any input can be added via AddString().
327 void Init() { output_->clear(); }
328
329 // Add an input string, reformatting to fit the desired dimensions.
330 // AddString() may be called multiple times to concatenate together
331 // multiple strings into the region (the current caller doesn't do
332 // this, however).
333 void AddString(const base::string16& input);
334
335 // Perform any deferred output processing. Must be called after the
336 // last AddString() call has occurred.
337 bool Finalize();
338
339 private:
340 // Add a line to the rectangular region at the current position,
341 // either by itself or by breaking it into words.
342 void AddLine(const base::string16& line);
343
344 // Add a word to the rectangular region at the current position,
345 // either by itself or by breaking it into characters.
346 void AddWord(const base::string16& word);
347
348 // Add text to the output string if the rectangular boundaries
349 // have not been exceeded, advancing the current position.
350 void Append(const base::string16& string);
351
352 // Set the current position to the beginning of the next line. If
353 // |output| is true, add a newline to the output string if the rectangular
354 // boundaries have not been exceeded. If |output| is false, we assume
355 // some other mechanism will (likely) do similar breaking after the fact.
356 void NewLine(bool output);
357
358 // Maximum number of rows allowed in the output string.
359 size_t max_rows_;
360
361 // Maximum number of characters allowed in the output string.
362 size_t max_cols_;
363
364 // Current row position, always incremented and may exceed max_rows_
365 // when the input can not fit in the region. We stop appending to
366 // the output string, however, when this condition occurs. In the
367 // future, we may want to expose this value to allow the caller to
368 // determine how many rows would actually be required to hold the
369 // formatted string.
370 size_t current_row_;
371
372 // Current character position, should never exceed max_cols_.
373 size_t current_col_;
374
375 // True when we do whitespace to newline conversions ourselves.
376 bool strict_;
377
378 // True when some of the input has been truncated.
379 bool suppressed_;
380
381 // String onto which the output is accumulated.
382 base::string16* output_;
383
384 DISALLOW_COPY_AND_ASSIGN(RectangleString);
385 };
386
387 void RectangleString::AddString(const base::string16& input) {
388 base::i18n::BreakIterator lines(input,
389 base::i18n::BreakIterator::BREAK_NEWLINE);
390 if (lines.Init()) {
391 while (lines.Advance())
392 AddLine(lines.GetString());
393 } else {
394 NOTREACHED() << "BreakIterator (lines) init failed";
395 }
396 }
397
398 bool RectangleString::Finalize() {
399 if (suppressed_) {
400 output_->append(ASCIIToUTF16("..."));
401 return true;
402 }
403 return false;
404 }
405
406 void RectangleString::AddLine(const base::string16& line) {
407 if (line.length() < max_cols_) {
408 Append(line);
409 } else {
410 base::i18n::BreakIterator words(line,
411 base::i18n::BreakIterator::BREAK_SPACE);
412 if (words.Init()) {
413 while (words.Advance())
414 AddWord(words.GetString());
415 } else {
416 NOTREACHED() << "BreakIterator (words) init failed";
417 }
418 }
419 // Account for naturally-occuring newlines.
420 ++current_row_;
421 current_col_ = 0;
422 }
423
424 void RectangleString::AddWord(const base::string16& word) {
425 if (word.length() < max_cols_) {
426 // Word can be made to fit, no need to fragment it.
427 if (current_col_ + word.length() >= max_cols_)
428 NewLine(strict_);
429 Append(word);
430 } else {
431 // Word is so big that it must be fragmented.
432 int array_start = 0;
433 int char_start = 0;
434 base::i18n::UTF16CharIterator chars(&word);
435 while (!chars.end()) {
436 // When boundary is hit, add as much as will fit on this line.
437 if (current_col_ + (chars.char_pos() - char_start) >= max_cols_) {
438 Append(word.substr(array_start, chars.array_pos() - array_start));
439 NewLine(true);
440 array_start = chars.array_pos();
441 char_start = chars.char_pos();
442 }
443 chars.Advance();
444 }
445 // Add the last remaining fragment, if any.
446 if (array_start != chars.array_pos())
447 Append(word.substr(array_start, chars.array_pos() - array_start));
448 }
449 }
450
451 void RectangleString::Append(const base::string16& string) {
452 if (current_row_ < max_rows_)
453 output_->append(string);
454 else
455 suppressed_ = true;
456 current_col_ += string.length();
457 }
458
459 void RectangleString::NewLine(bool output) {
460 if (current_row_ < max_rows_) {
461 if (output)
462 output_->append(ASCIIToUTF16("\n"));
463 } else {
464 suppressed_ = true;
465 }
466 ++current_row_;
467 current_col_ = 0;
468 }
469
470 // Internal class used to track progress of a rectangular text elide
471 // operation. Exists so the top-level ElideRectangleText() function
472 // can be broken into smaller methods sharing this state.
473 class RectangleText {
474 public:
475 RectangleText(const FontList& font_list,
476 float available_pixel_width,
477 int available_pixel_height,
478 WordWrapBehavior wrap_behavior,
479 std::vector<base::string16>* lines)
480 : font_list_(font_list),
481 line_height_(font_list.GetHeight()),
482 available_pixel_width_(available_pixel_width),
483 available_pixel_height_(available_pixel_height),
484 wrap_behavior_(wrap_behavior),
485 current_width_(0),
486 current_height_(0),
487 last_line_ended_in_lf_(false),
488 lines_(lines),
489 insufficient_width_(false),
490 insufficient_height_(false) {}
491
492 // Perform deferred initializions following creation. Must be called
493 // before any input can be added via AddString().
494 void Init() { lines_->clear(); }
495
496 // Add an input string, reformatting to fit the desired dimensions.
497 // AddString() may be called multiple times to concatenate together
498 // multiple strings into the region (the current caller doesn't do
499 // this, however).
500 void AddString(const base::string16& input);
501
502 // Perform any deferred output processing. Must be called after the last
503 // AddString() call has occured. Returns a combination of
504 // |ReformattingResultFlags| indicating whether the given width or height was
505 // insufficient, leading to elision or truncation.
506 int Finalize();
507
508 private:
509 // Add a line to the rectangular region at the current position,
510 // either by itself or by breaking it into words.
511 void AddLine(const base::string16& line);
512
513 // Wrap the specified word across multiple lines.
514 int WrapWord(const base::string16& word);
515
516 // Add a long word - wrapping, eliding or truncating per the wrap behavior.
517 int AddWordOverflow(const base::string16& word);
518
519 // Add a word to the rectangluar region at the current position.
520 int AddWord(const base::string16& word);
521
522 // Append the specified |text| to the current output line, incrementing the
523 // running width by the specified amount. This is an optimization over
524 // |AddToCurrentLine()| when |text_width| is already known.
525 void AddToCurrentLineWithWidth(const base::string16& text, float text_width);
526
527 // Append the specified |text| to the current output line.
528 void AddToCurrentLine(const base::string16& text);
529
530 // Set the current position to the beginning of the next line.
531 bool NewLine();
532
533 // The font list used for measuring text width.
534 const FontList& font_list_;
535
536 // The height of each line of text.
537 const int line_height_;
538
539 // The number of pixels of available width in the rectangle.
540 const float available_pixel_width_;
541
542 // The number of pixels of available height in the rectangle.
543 const int available_pixel_height_;
544
545 // The wrap behavior for words that are too long to fit on a single line.
546 const WordWrapBehavior wrap_behavior_;
547
548 // The current running width.
549 float current_width_;
550
551 // The current running height.
552 int current_height_;
553
554 // The current line of text.
555 base::string16 current_line_;
556
557 // Indicates whether the last line ended with \n.
558 bool last_line_ended_in_lf_;
559
560 // The output vector of lines.
561 std::vector<base::string16>* lines_;
562
563 // Indicates whether a word was so long that it had to be truncated or elided
564 // to fit the available width.
565 bool insufficient_width_;
566
567 // Indicates whether there were too many lines for the available height.
568 bool insufficient_height_;
569
570 DISALLOW_COPY_AND_ASSIGN(RectangleText);
571 };
572
573 void RectangleText::AddString(const base::string16& input) {
574 base::i18n::BreakIterator lines(input,
575 base::i18n::BreakIterator::BREAK_NEWLINE);
576 if (lines.Init()) {
577 while (!insufficient_height_ && lines.Advance()) {
578 base::string16 line = lines.GetString();
579 // The BREAK_NEWLINE iterator will keep the trailing newline character,
580 // except in the case of the last line, which may not have one. Remove
581 // the newline character, if it exists.
582 last_line_ended_in_lf_ = !line.empty() && line[line.length() - 1] == '\n';
583 if (last_line_ended_in_lf_)
584 line.resize(line.length() - 1);
585 AddLine(line);
586 }
587 } else {
588 NOTREACHED() << "BreakIterator (lines) init failed";
589 }
590 }
591
592 int RectangleText::Finalize() {
593 // Remove trailing whitespace from the last line or remove the last line
594 // completely, if it's just whitespace.
595 if (!insufficient_height_ && !lines_->empty()) {
596 base::TrimWhitespace(lines_->back(), base::TRIM_TRAILING, &lines_->back());
597 if (lines_->back().empty() && !last_line_ended_in_lf_)
598 lines_->pop_back();
599 }
600 if (last_line_ended_in_lf_)
601 lines_->push_back(base::string16());
602 return (insufficient_width_ ? INSUFFICIENT_SPACE_HORIZONTAL : 0) |
603 (insufficient_height_ ? INSUFFICIENT_SPACE_VERTICAL : 0);
604 }
605
606 void RectangleText::AddLine(const base::string16& line) {
607 const float line_width = GetStringWidthF(line, font_list_);
608 if (line_width <= available_pixel_width_) {
609 AddToCurrentLineWithWidth(line, line_width);
610 } else {
611 // Iterate over positions that are valid to break the line at. In general,
612 // these are word boundaries but after any punctuation following the word.
613 base::i18n::BreakIterator words(line,
614 base::i18n::BreakIterator::BREAK_LINE);
615 if (words.Init()) {
616 while (words.Advance()) {
617 const bool truncate = !current_line_.empty();
618 const base::string16& word = words.GetString();
619 const int lines_added = AddWord(word);
620 if (lines_added) {
621 if (truncate) {
622 // Trim trailing whitespace from the line that was added.
623 const int line = lines_->size() - lines_added;
624 base::TrimWhitespace(lines_->at(line), base::TRIM_TRAILING,
625 &lines_->at(line));
626 }
627 if (base::ContainsOnlyChars(word, base::kWhitespaceUTF16)) {
628 // Skip the first space if the previous line was carried over.
629 current_width_ = 0;
630 current_line_.clear();
631 }
632 }
633 }
634 } else {
635 NOTREACHED() << "BreakIterator (words) init failed";
636 }
637 }
638 // Account for naturally-occuring newlines.
639 NewLine();
640 }
641
642 int RectangleText::WrapWord(const base::string16& word) {
643 // Word is so wide that it must be fragmented.
644 base::string16 text = word;
645 int lines_added = 0;
646 bool first_fragment = true;
647 while (!insufficient_height_ && !text.empty()) {
648 base::string16 fragment =
649 ElideText(text, font_list_, available_pixel_width_, TRUNCATE);
650 // At least one character has to be added at every line, even if the
651 // available space is too small.
652 if (fragment.empty())
653 fragment = text.substr(0, 1);
654 if (!first_fragment && NewLine())
655 lines_added++;
656 AddToCurrentLine(fragment);
657 text = text.substr(fragment.length());
658 first_fragment = false;
659 }
660 return lines_added;
661 }
662
663 int RectangleText::AddWordOverflow(const base::string16& word) {
664 int lines_added = 0;
665
666 // Unless this is the very first word, put it on a new line.
667 if (!current_line_.empty()) {
668 if (!NewLine())
669 return 0;
670 lines_added++;
671 }
672
673 if (wrap_behavior_ == IGNORE_LONG_WORDS) {
674 current_line_ = word;
675 current_width_ = available_pixel_width_;
676 } else if (wrap_behavior_ == WRAP_LONG_WORDS) {
677 lines_added += WrapWord(word);
678 } else {
679 const ElideBehavior elide_behavior =
680 (wrap_behavior_ == ELIDE_LONG_WORDS ? ELIDE_TAIL : TRUNCATE);
681 const base::string16 elided_word =
682 ElideText(word, font_list_, available_pixel_width_, elide_behavior);
683 AddToCurrentLine(elided_word);
684 insufficient_width_ = true;
685 }
686
687 return lines_added;
688 }
689
690 int RectangleText::AddWord(const base::string16& word) {
691 int lines_added = 0;
692 base::string16 trimmed;
693 base::TrimWhitespace(word, base::TRIM_TRAILING, &trimmed);
694 const float trimmed_width = GetStringWidthF(trimmed, font_list_);
695 if (trimmed_width <= available_pixel_width_) {
696 // Word can be made to fit, no need to fragment it.
697 if ((current_width_ + trimmed_width > available_pixel_width_) && NewLine())
698 lines_added++;
699 // Append the non-trimmed word, in case more words are added after.
700 AddToCurrentLine(word);
701 } else {
702 lines_added = AddWordOverflow(wrap_behavior_ == IGNORE_LONG_WORDS ?
703 trimmed : word);
704 }
705 return lines_added;
706 }
707
708 void RectangleText::AddToCurrentLine(const base::string16& text) {
709 AddToCurrentLineWithWidth(text, GetStringWidthF(text, font_list_));
710 }
711
712 void RectangleText::AddToCurrentLineWithWidth(const base::string16& text,
713 float text_width) {
714 if (current_height_ >= available_pixel_height_) {
715 insufficient_height_ = true;
716 return;
717 }
718 current_line_.append(text);
719 current_width_ += text_width;
720 }
721
722 bool RectangleText::NewLine() {
723 bool line_added = false;
724 if (current_height_ < available_pixel_height_) {
725 lines_->push_back(current_line_);
726 current_line_.clear();
727 line_added = true;
728 } else {
729 insufficient_height_ = true;
730 }
731 current_height_ += line_height_;
732 current_width_ = 0;
733 return line_added;
734 }
735
736 } // namespace
737
738 bool ElideRectangleString(const base::string16& input, size_t max_rows,
739 size_t max_cols, bool strict,
740 base::string16* output) {
741 RectangleString rect(max_rows, max_cols, strict, output);
742 rect.Init();
743 rect.AddString(input);
744 return rect.Finalize();
745 }
746
747 int ElideRectangleText(const base::string16& input,
748 const FontList& font_list,
749 float available_pixel_width,
750 int available_pixel_height,
751 WordWrapBehavior wrap_behavior,
752 std::vector<base::string16>* lines) {
753 RectangleText rect(font_list,
754 available_pixel_width,
755 available_pixel_height,
756 wrap_behavior,
757 lines);
758 rect.Init();
759 rect.AddString(input);
760 return rect.Finalize();
761 }
762
763 base::string16 TruncateString(const base::string16& string,
764 size_t length,
765 BreakType break_type) {
766 DCHECK(break_type == CHARACTER_BREAK || break_type == WORD_BREAK);
767
768 if (string.size() <= length)
769 // String fits, return it.
770 return string;
771
772 if (length == 0)
773 // No room for the elide string, return an empty string.
774 return base::string16();
775
776 size_t max = length - 1;
777
778 // Added to the end of strings that are too big.
779 static const base::char16 kElideString[] = { 0x2026, 0 };
780
781 if (max == 0)
782 // Just enough room for the elide string.
783 return kElideString;
784
785 int32_t index = static_cast<int32_t>(max);
786 if (break_type == WORD_BREAK) {
787 // Use a line iterator to find the first boundary.
788 UErrorCode status = U_ZERO_ERROR;
789 scoped_ptr<icu::BreakIterator> bi(
790 icu::RuleBasedBreakIterator::createLineInstance(
791 icu::Locale::getDefault(), status));
792 if (U_FAILURE(status))
793 return string.substr(0, max) + kElideString;
794 bi->setText(string.c_str());
795 index = bi->preceding(index);
796 if (index == icu::BreakIterator::DONE || index == 0) {
797 // We either found no valid line break at all, or one right at the
798 // beginning of the string. Go back to the end; we'll have to break in the
799 // middle of a word.
800 index = static_cast<int32_t>(max);
801 }
802 }
803
804 // Use a character iterator to find the previous non-whitespace character.
805 icu::StringCharacterIterator char_iterator(string.c_str());
806 char_iterator.setIndex(index);
807 while (char_iterator.hasPrevious()) {
808 char_iterator.previous();
809 if (!(u_isspace(char_iterator.current()) ||
810 u_charType(char_iterator.current()) == U_CONTROL_CHAR ||
811 u_charType(char_iterator.current()) == U_NON_SPACING_MARK)) {
812 // Not a whitespace character. Advance the iterator so that we
813 // include the current character in the truncated string.
814 char_iterator.next();
815 break;
816 }
817 }
818 if (char_iterator.hasPrevious()) {
819 // Found a valid break point.
820 index = char_iterator.getIndex();
821 } else {
822 // String has leading whitespace, return the elide string.
823 return kElideString;
824 }
825
826 return string.substr(0, index) + kElideString;
827 }
828
829 } // namespace gfx
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