Revert 112305 - Pull the phone library directly. Delete old version.

third_party/libphonenumber/cpp/src/phonenumberutil.cc

+// Copyright (C) 2009 Google Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Author: Shaopeng Jia
+// Open-sourced by: Philippe Liard
+
+#include "phonenumberutil.h"
+
+#include <algorithm>
+#include <cctype>
+#include <cstddef>
+#include <fstream>
+#include <iostream>
+#include <iterator>
+#include <map>
+#include <sstream>
+#include <utility>
+#include <vector>
+
+#include <google/protobuf/message_lite.h>
+#include <unicode/uchar.h>
+#include <unicode/utf8.h>
+
+#include "base/logging.h"
+#include "base/memory/singleton.h"
+#include "default_logger.h"
+#include "encoding_utils.h"
+#include "metadata.h"
+#include "normalize_utf8.h"
+#include "phonemetadata.pb.h"
+#include "phonenumber.h"
+#include "phonenumber.pb.h"
+#include "regexp_adapter.h"
+#include "regexp_cache.h"
+#include "region_code.h"
+#include "stl_util.h"
+#include "stringutil.h"
+#include "utf/unicodetext.h"
+#include "utf/utf.h"
+
+namespace i18n {
+namespace phonenumbers {
+
+using std::cerr;
+using std::endl;
+using std::ifstream;
+using std::make_pair;
+using std::sort;
+using std::stringstream;
+
+using google::protobuf::RepeatedPtrField;
+
+// static
+const char PhoneNumberUtil::kPlusChars[] = "+\xEF\xBC\x8B";
+// To find out the unicode code-point of the characters below in vim, highlight
+// the character and type 'ga'. Note that the - is used to express ranges of
+// full-width punctuation below, as well as being present in the expression
+// itself. In emacs, you can use M-x unicode-what to query information about the
+// unicode character.
+// static
+const char PhoneNumberUtil::kValidPunctuation[] =
+    "-x\xE2\x80\x90-\xE2\x80\x95\xE2\x88\x92\xE3\x83\xBC\xEF\xBC\x8D-\xEF\xBC\x8F \xC2\xA0\xE2\x80\x8B\xE2\x81\xA0\xE3\x80\x80()\xEF\xBC\x88\xEF\xBC\x89\xEF\xBC\xBB\xEF\xBC\xBD.\\[\\]/~\xE2\x81\x93\xE2\x88\xBC";
+
+namespace {
+
+scoped_ptr<Logger> logger_;
+scoped_ptr<RegExpCache> regexp_cache;
+
+// These objects are created in the function InitializeStaticMapsAndSets.
+
+// These mappings map a character (key) to a specific digit that should replace
+// it for normalization purposes.
+scoped_ptr<map<char32, char> > alpha_mappings;
+// For performance reasons, store a map of combining alpha_mappings with ASCII
+// digits.
+scoped_ptr<map<char32, char> > alpha_phone_mappings;
+// Separate map of all symbols that we wish to retain when formatting alpha
+// numbers. This includes digits, ascii letters and number grouping symbols such
+// as "-" and " ".
+scoped_ptr<map<char32, char> > all_plus_number_grouping_symbols;
+
+// The kPlusSign signifies the international prefix.
+const char kPlusSign[] = "+";
+
+scoped_ptr<const RegExp> plus_chars_pattern;
+
+const char kRfc3966ExtnPrefix[] = ";ext=";
+
+// Pattern that makes it easy to distinguish whether a region has a unique
+// international dialing prefix or not. If a region has a unique international
+// prefix (e.g. 011 in USA), it will be represented as a string that contains a
+// sequence of ASCII digits. If there are multiple available international
+// prefixes in a region, they will be represented as a regex string that always
+// contains character(s) other than ASCII digits.
+// Note this regex also includes tilde, which signals waiting for the tone.
+scoped_ptr<const RegExp> unique_international_prefix;
+
+const char kDigits[] = "\\p{Nd}";
+scoped_ptr<const RegExp> digits_pattern;
+// We accept alpha characters in phone numbers, ASCII only. We store lower-case
+// here only since our regular expressions are case-insensitive.
+const char kValidAlpha[] = "a-z";
+scoped_ptr<const RegExp> capturing_digit_pattern;
+scoped_ptr<const RegExp> capturing_ascii_digits_pattern;
+
+// Regular expression of acceptable characters that may start a phone number
+// for the purposes of parsing. This allows us to strip away meaningless
+// prefixes to phone numbers that may be mistakenly given to us. This
+// consists of digits, the plus symbol and arabic-indic digits. This does
+// not contain alpha characters, although they may be used later in the
+// number. It also does not include other punctuation, as this will be
+// stripped later during parsing and is of no information value when parsing
+// a number. The string starting with this valid character is captured.
+// This corresponds to VALID_START_CHAR in the java version.
+scoped_ptr<const string> valid_start_char;
+scoped_ptr<const RegExp> valid_start_char_pattern;
+
+// Regular expression of characters typically used to start a second phone
+// number for the purposes of parsing. This allows us to strip off parts of
+// the number that are actually the start of another number, such as for:
+// (530) 583-6985 x302/x2303 -> the second extension here makes this actually
+// two phone numbers, (530) 583-6985 x302 and (530) 583-6985 x2303. We remove
+// the second extension so that the first number is parsed correctly. The string
+// preceding this is captured.
+// This corresponds to SECOND_NUMBER_START in the java version.
+const char kCaptureUpToSecondNumberStart[] = "(.*)[\\\\/] *x";
+scoped_ptr<const RegExp> capture_up_to_second_number_start_pattern;
+
+// Regular expression of trailing characters that we want to remove. We remove
+// all characters that are not alpha or numerical characters. The hash
+// character is retained here, as it may signify the previous block was an
+// extension. Note the capturing block at the start to capture the rest of the
+// number if this was a match.
+// This corresponds to UNWANTED_END_CHARS in the java version.
+const char kUnwantedEndChar[] = "[^\\p{N}\\p{L}#]";
+scoped_ptr<const RegExp> unwanted_end_char_pattern;
+
+// Regular expression of groups of valid punctuation characters.
+scoped_ptr<const RegExp> separator_pattern;
+
+// Regular expression of viable phone numbers. This is location independent.
+// Checks we have at least three leading digits, and only valid punctuation,
+// alpha characters and digits in the phone number. Does not include extension
+// data. The symbol 'x' is allowed here as valid punctuation since it is often
+// used as a placeholder for carrier codes, for example in Brazilian phone
+// numbers. We also allow multiple plus-signs at the start.
+// Corresponds to the following:
+// plus_sign*([punctuation]*[digits]){3,}([punctuation]|[digits]|[alpha])*
+scoped_ptr<const string> valid_phone_number;
+
+// Default extension prefix to use when formatting. This will be put in front of
+// any extension component of the number, after the main national number is
+// formatted. For example, if you wish the default extension formatting to be "
+// extn: 3456", then you should specify " extn: " here as the default extension
+// prefix. This can be overridden by region-specific preferences.
+const char kDefaultExtnPrefix[] = " ext. ";
+
+// Regexp of all possible ways to write extensions, for use when parsing. This
+// will be run as a case-insensitive regexp match. Wide character versions are
+// also provided after each ascii version. There are three regular expressions
+// here. The first covers RFC 3966 format, where the extension is added using
+// ";ext=". The second more generic one starts with optional white space and
+// ends with an optional full stop (.), followed by zero or more spaces/tabs and
+// then the numbers themselves. The third one covers the special case of
+// American numbers where the extension is written with a hash at the end, such
+// as "- 503#".
+// Note that the only capturing groups should be around the digits that you want
+// to capture as part of the extension, or else parsing will fail!
+scoped_ptr<const string> known_extn_patterns;
+// Regexp of all known extension prefixes used by different regions followed
+// by 1 or more valid digits, for use when parsing.
+scoped_ptr<const RegExp> extn_pattern;
+
+// We append optionally the extension pattern to the end here, as a valid phone
+// number may have an extension prefix appended, followed by 1 or more digits.
+scoped_ptr<const RegExp> valid_phone_number_pattern;
+
+// We use this pattern to check if the phone number has at least three letters
+// in it - if so, then we treat it as a number where some phone-number digits
+// are represented by letters.
+scoped_ptr<const RegExp> valid_alpha_phone_pattern;
+
+scoped_ptr<const RegExp> first_group_capturing_pattern;
+
+scoped_ptr<const RegExp> carrier_code_pattern;
+
+bool LoadCompiledInMetadata(PhoneMetadataCollection* metadata) {
+  if (!metadata->ParseFromArray(metadata_get(), metadata_size())) {
+    cerr << "Could not parse binary data." << endl;
+    return false;
+  }
+  return true;
+}
+
+// Returns a pointer to the description inside the metadata of the appropriate
+// type.
+const PhoneNumberDesc* GetNumberDescByType(
+    const PhoneMetadata& metadata,
+    PhoneNumberUtil::PhoneNumberType type) {
+  switch (type) {
+    case PhoneNumberUtil::PREMIUM_RATE:
+      return &metadata.premium_rate();
+    case PhoneNumberUtil::TOLL_FREE:
+      return &metadata.toll_free();
+    case PhoneNumberUtil::MOBILE:
+      return &metadata.mobile();
+    case PhoneNumberUtil::FIXED_LINE:
+    case PhoneNumberUtil::FIXED_LINE_OR_MOBILE:
+      return &metadata.fixed_line();
+    case PhoneNumberUtil::SHARED_COST:
+      return &metadata.shared_cost();
+    case PhoneNumberUtil::VOIP:
+      return &metadata.voip();
+    case PhoneNumberUtil::PERSONAL_NUMBER:
+      return &metadata.personal_number();
+    case PhoneNumberUtil::PAGER:
+      return &metadata.pager();
+    case PhoneNumberUtil::UAN:
+      return &metadata.uan();
+    default:
+      return &metadata.general_desc();
+  }
+}
+
+// A helper function that is used by Format and FormatByPattern.
+void FormatNumberByFormat(int country_calling_code,
+                          PhoneNumberUtil::PhoneNumberFormat number_format,
+                          const string& formatted_national_number,
+                          const string& formatted_extension,
+                          string* formatted_number) {
+  switch (number_format) {
+    case PhoneNumberUtil::E164:
+      formatted_number->assign(StrCat(kPlusSign,
+                                      SimpleItoa(country_calling_code),
+                                      formatted_national_number,
+                                      formatted_extension));
+      return;
+    case PhoneNumberUtil::INTERNATIONAL:
+      formatted_number->assign(StrCat(kPlusSign,
+                                      SimpleItoa(country_calling_code),
+                                      " ",
+                                      formatted_national_number,
+                                      formatted_extension));
+      return;
+    case PhoneNumberUtil::RFC3966:
+      formatted_number->assign(StrCat(kPlusSign,
+                                      SimpleItoa(country_calling_code),
+                                      "-",
+                                      formatted_national_number,
+                                      formatted_extension));
+      return;
+    case PhoneNumberUtil::NATIONAL:
+    default:
+      formatted_number->assign(StrCat(formatted_national_number,
+                                      formatted_extension));
+  }
+}
+
+// The number_for_leading_digits_match is a separate parameter, because for
+// alpha numbers we want to pass in the numeric version to select the right
+// formatting rule, but then we actually apply the formatting pattern to the
+// national_number (which in this case has alpha characters in it).
+//
+// Note that carrier_code is optional - if an empty string, no carrier code
+// replacement will take place.
+void FormatAccordingToFormatsWithCarrier(
+    const string& number_for_leading_digits_match,
+    const RepeatedPtrField<NumberFormat>& available_formats,
+    PhoneNumberUtil::PhoneNumberFormat number_format,
+    const string& national_number,
+    const string& carrier_code,
+    string* formatted_number) {
+  DCHECK(formatted_number);
+  for (RepeatedPtrField<NumberFormat>::const_iterator
+       it = available_formats.begin(); it != available_formats.end(); ++it) {
+    int size = it->leading_digits_pattern_size();
+    if (size > 0) {
+      const scoped_ptr<RegExpInput> number_copy(
+          RegExpInput::Create(number_for_leading_digits_match));
+      // We always use the last leading_digits_pattern, as it is the most
+      // detailed.
+      if (!regexp_cache->GetRegExp(it->leading_digits_pattern(size - 1))
+              .Consume(number_copy.get())) {
+        continue;
+      }
+    }
+    const RegExp& pattern_to_match(regexp_cache->GetRegExp(it->pattern()));
+    if (pattern_to_match.FullMatch(national_number)) {
+      string formatting_pattern(it->format());
+      if (number_format == PhoneNumberUtil::NATIONAL &&
+          carrier_code.length() > 0 &&
+          it->domestic_carrier_code_formatting_rule().length() > 0) {
+        // Replace the $CC in the formatting rule with the desired carrier code.
+        string carrier_code_formatting_rule =
+            it->domestic_carrier_code_formatting_rule();
+        carrier_code_pattern->Replace(&carrier_code_formatting_rule,
+                                      carrier_code);
+        first_group_capturing_pattern->Replace(&formatting_pattern,
+                                               carrier_code_formatting_rule);
+      } else {
+        // Use the national prefix formatting rule instead.
+        string national_prefix_formatting_rule =
+          it->national_prefix_formatting_rule();
+        if (number_format == PhoneNumberUtil::NATIONAL &&
+            national_prefix_formatting_rule.length() > 0) {
+          // Apply the national_prefix_formatting_rule as the formatting_pattern
+          // contains only information on how the national significant number
+          // should be formatted at this point.
+          first_group_capturing_pattern->Replace(
+              &formatting_pattern, national_prefix_formatting_rule);
+        }
+      }
+      formatted_number->assign(national_number);
+      pattern_to_match.GlobalReplace(formatted_number, formatting_pattern);
+      return;
+    }
+  }
+  // If no pattern above is matched, we format the number as a whole.
+  formatted_number->assign(national_number);
+}
+
+// Simple wrapper of FormatAccordingToFormatsWithCarrier for the common case of
+// no carrier code.
+void FormatAccordingToFormats(
+    const string& number_for_leading_digits_match,
+    const RepeatedPtrField<NumberFormat>& available_formats,
+    PhoneNumberUtil::PhoneNumberFormat number_format,
+    const string& national_number,
+    string* formatted_number) {
+  DCHECK(formatted_number);
+  FormatAccordingToFormatsWithCarrier(number_for_leading_digits_match,
+                                      available_formats, number_format,
+                                      national_number, "", formatted_number);
+}
+
+// Returns true when one national number is the suffix of the other or both are
+// the same.
+bool IsNationalNumberSuffixOfTheOther(const PhoneNumber& first_number,
+                                      const PhoneNumber& second_number) {
+  const string& first_number_national_number =
+    SimpleItoa(static_cast<uint64>(first_number.national_number()));
+  const string& second_number_national_number =
+    SimpleItoa(static_cast<uint64>(second_number.national_number()));
+  // Note that HasSuffixString returns true if the numbers are equal.
+  return HasSuffixString(first_number_national_number,
+                         second_number_national_number) ||
+         HasSuffixString(second_number_national_number,
+                         first_number_national_number);
+}
+
+bool IsNumberMatchingDesc(const string& national_number,
+                          const PhoneNumberDesc& number_desc) {
+  return regexp_cache->GetRegExp(number_desc.possible_number_pattern())
+             .FullMatch(national_number) &&
+         regexp_cache->GetRegExp(number_desc.national_number_pattern())
+             .FullMatch(national_number);
+}
+
+PhoneNumberUtil::PhoneNumberType GetNumberTypeHelper(
+    const string& national_number, const PhoneMetadata& metadata) {
+  const PhoneNumberDesc& general_desc = metadata.general_desc();
+  if (!general_desc.has_national_number_pattern() ||
+      !IsNumberMatchingDesc(national_number, general_desc)) {
+    VLOG(4) << "Number type unknown - doesn't match general national number"
+            << " pattern.";
+    return PhoneNumberUtil::UNKNOWN;
+  }
+  if (IsNumberMatchingDesc(national_number, metadata.premium_rate())) {
+    VLOG(4) << "Number is a premium number.";
+    return PhoneNumberUtil::PREMIUM_RATE;
+  }
+  if (IsNumberMatchingDesc(national_number, metadata.toll_free())) {
+    VLOG(4) << "Number is a toll-free number.";
+    return PhoneNumberUtil::TOLL_FREE;
+  }
+  if (IsNumberMatchingDesc(national_number, metadata.shared_cost())) {
+    VLOG(4) << "Number is a shared cost number.";
+    return PhoneNumberUtil::SHARED_COST;
+  }
+  if (IsNumberMatchingDesc(national_number, metadata.voip())) {
+    VLOG(4) << "Number is a VOIP (Voice over IP) number.";
+    return PhoneNumberUtil::VOIP;
+  }
+  if (IsNumberMatchingDesc(national_number, metadata.personal_number())) {
+    VLOG(4) << "Number is a personal number.";
+    return PhoneNumberUtil::PERSONAL_NUMBER;
+  }
+  if (IsNumberMatchingDesc(national_number, metadata.pager())) {
+    VLOG(4) << "Number is a pager number.";
+    return PhoneNumberUtil::PAGER;
+  }
+  if (IsNumberMatchingDesc(national_number, metadata.uan())) {
+    VLOG(4) << "Number is a UAN.";
+    return PhoneNumberUtil::UAN;
+  }
+
+  bool is_fixed_line =
+      IsNumberMatchingDesc(national_number, metadata.fixed_line());
+  if (is_fixed_line) {
+    if (metadata.same_mobile_and_fixed_line_pattern()) {
+      VLOG(4) << "Fixed-line and mobile patterns equal, number is fixed-line"
+              << " or mobile";
+      return PhoneNumberUtil::FIXED_LINE_OR_MOBILE;
+    } else if (IsNumberMatchingDesc(national_number, metadata.mobile())) {
+      VLOG(4) << "Fixed-line and mobile patterns differ, but number is "
+              << "still fixed-line or mobile";
+      return PhoneNumberUtil::FIXED_LINE_OR_MOBILE;
+    }
+    VLOG(4) << "Number is a fixed line number.";
+    return PhoneNumberUtil::FIXED_LINE;
+  }
+  // Otherwise, test to see if the number is mobile. Only do this if certain
+  // that the patterns for mobile and fixed line aren't the same.
+  if (!metadata.same_mobile_and_fixed_line_pattern() &&
+      IsNumberMatchingDesc(national_number, metadata.mobile())) {
+    VLOG(4) << "Number is a mobile number.";
+    return PhoneNumberUtil::MOBILE;
+  }
+  VLOG(4) << "Number type unknown - doesn\'t match any specific number type"
+          << " pattern.";
+  return PhoneNumberUtil::UNKNOWN;
+}
+
+char32 ToUnicodeCodepoint(const char* unicode_char) {
+  char32 codepoint;
+  EncodingUtils::DecodeUTF8Char(unicode_char, &codepoint);
+  return codepoint;
+}
+
+void InitializeStaticMapsAndSets() {
+  // Create global objects.
+  regexp_cache.reset(new RegExpCache(128));
+  all_plus_number_grouping_symbols.reset(new map<char32, char>);
+  alpha_mappings.reset(new map<char32, char>);
+  alpha_phone_mappings.reset(new map<char32, char>);
+
+  // Punctuation that we wish to respect in alpha numbers, as they show number
+  // groupings are mapped here.
+  all_plus_number_grouping_symbols->insert(
+      make_pair(ToUnicodeCodepoint("-"), '-'));
+  all_plus_number_grouping_symbols->insert(
+      make_pair(ToUnicodeCodepoint("\xEF\xBC\x8D"), '-'));
+  all_plus_number_grouping_symbols->insert(
+      make_pair(ToUnicodeCodepoint("\xE2\x80\x90"), '-'));
+  all_plus_number_grouping_symbols->insert(
+      make_pair(ToUnicodeCodepoint("\xE2\x80\x91"), '-'));
+  all_plus_number_grouping_symbols->insert(
+      make_pair(ToUnicodeCodepoint("\xE2\x80\x92"), '-'));
+  all_plus_number_grouping_symbols->insert(
+      make_pair(ToUnicodeCodepoint("\xE2\x80\x93"), '-'));
+  all_plus_number_grouping_symbols->insert(
+      make_pair(ToUnicodeCodepoint("\xE2\x80\x94"), '-'));
+  all_plus_number_grouping_symbols->insert(
+      make_pair(ToUnicodeCodepoint("\xE2\x80\x95"), '-'));
+  all_plus_number_grouping_symbols->insert(
+      make_pair(ToUnicodeCodepoint("\xE2\x88\x92"), '-'));
+  all_plus_number_grouping_symbols->insert(
+      make_pair(ToUnicodeCodepoint("/"), '/'));
+  all_plus_number_grouping_symbols->insert(
+      make_pair(ToUnicodeCodepoint("\xEF\xBC\x8F"), '/'));
+  all_plus_number_grouping_symbols->insert(
+      make_pair(ToUnicodeCodepoint(" "), ' '));
+  all_plus_number_grouping_symbols->insert(
+      make_pair(ToUnicodeCodepoint("\xE3\x80\x80"), ' '));
+  all_plus_number_grouping_symbols->insert(
+      make_pair(ToUnicodeCodepoint("\xE2\x81\xA0"), ' '));
+  all_plus_number_grouping_symbols->insert(
+      make_pair(ToUnicodeCodepoint("."), '.'));
+  all_plus_number_grouping_symbols->insert(
+      make_pair(ToUnicodeCodepoint("\xEF\xBC\x8E"), '.'));
+  // Only the upper-case letters are added here - the lower-case versions are
+  // added programmatically.
+  alpha_mappings->insert(make_pair(ToUnicodeCodepoint("A"), '2'));
+  alpha_mappings->insert(make_pair(ToUnicodeCodepoint("B"), '2'));
+  alpha_mappings->insert(make_pair(ToUnicodeCodepoint("C"), '2'));
+  alpha_mappings->insert(make_pair(ToUnicodeCodepoint("D"), '3'));
+  alpha_mappings->insert(make_pair(ToUnicodeCodepoint("E"), '3'));
+  alpha_mappings->insert(make_pair(ToUnicodeCodepoint("F"), '3'));
+  alpha_mappings->insert(make_pair(ToUnicodeCodepoint("G"), '4'));
+  alpha_mappings->insert(make_pair(ToUnicodeCodepoint("H"), '4'));
+  alpha_mappings->insert(make_pair(ToUnicodeCodepoint("I"), '4'));
+  alpha_mappings->insert(make_pair(ToUnicodeCodepoint("J"), '5'));
+  alpha_mappings->insert(make_pair(ToUnicodeCodepoint("K"), '5'));
+  alpha_mappings->insert(make_pair(ToUnicodeCodepoint("L"), '5'));
+  alpha_mappings->insert(make_pair(ToUnicodeCodepoint("M"), '6'));
+  alpha_mappings->insert(make_pair(ToUnicodeCodepoint("N"), '6'));
+  alpha_mappings->insert(make_pair(ToUnicodeCodepoint("O"), '6'));
+  alpha_mappings->insert(make_pair(ToUnicodeCodepoint("P"), '7'));
+  alpha_mappings->insert(make_pair(ToUnicodeCodepoint("Q"), '7'));
+  alpha_mappings->insert(make_pair(ToUnicodeCodepoint("R"), '7'));
+  alpha_mappings->insert(make_pair(ToUnicodeCodepoint("S"), '7'));
+  alpha_mappings->insert(make_pair(ToUnicodeCodepoint("T"), '8'));
+  alpha_mappings->insert(make_pair(ToUnicodeCodepoint("U"), '8'));
+  alpha_mappings->insert(make_pair(ToUnicodeCodepoint("V"), '8'));
+  alpha_mappings->insert(make_pair(ToUnicodeCodepoint("W"), '9'));
+  alpha_mappings->insert(make_pair(ToUnicodeCodepoint("X"), '9'));
+  alpha_mappings->insert(make_pair(ToUnicodeCodepoint("Y"), '9'));
+  alpha_mappings->insert(make_pair(ToUnicodeCodepoint("Z"), '9'));
+  map<char32, char> lower_case_mappings;
+  map<char32, char> alpha_letters;
+  for (map<char32, char>::const_iterator it = alpha_mappings->begin();
+       it != alpha_mappings->end();
+       ++it) {
+    // Convert all the upper-case ASCII letters to lower-case.
+    if (it->first < 128) {
+      char letter_as_upper = static_cast<char>(it->first);
+      char32 letter_as_lower = static_cast<char32>(tolower(letter_as_upper));
+      lower_case_mappings.insert(make_pair(letter_as_lower, it->second));
+      // Add the letters in both variants to the alpha_letters map. This just
+      // pairs each letter with its upper-case representation so that it can be
+      // retained when normalising alpha numbers.
+      alpha_letters.insert(make_pair(letter_as_lower, letter_as_upper));
+      alpha_letters.insert(make_pair(it->first, letter_as_upper));
+    }
+  }
+  // In the Java version we don't insert the lower-case mappings in the map,
+  // because we convert to upper case on the fly. Doing this here would involve
+  // pulling in all of ICU, which we don't want to do if we don't have to.
+  alpha_mappings->insert(lower_case_mappings.begin(),
+                         lower_case_mappings.end());
+  alpha_phone_mappings->insert(alpha_mappings->begin(),
+                               alpha_mappings->end());
+  all_plus_number_grouping_symbols->insert(alpha_letters.begin(),
+                                           alpha_letters.end());
+  // Add the ASCII digits so that they don't get deleted by NormalizeHelper().
+  for (char c = '0'; c <= '9'; ++c) {
+    alpha_phone_mappings->insert(make_pair(c, c));
+    all_plus_number_grouping_symbols->insert(make_pair(c, c));
+  }
+}
+
+// Normalizes a string of characters representing a phone number by replacing
+// all characters found in the accompanying map with the values therein, and
+// stripping all other characters if remove_non_matches is true.
+// Parameters:
+// number - a pointer to a string of characters representing a phone number to
+//   be normalized.
+// normalization_replacements - a mapping of characters to what they should be
+//   replaced by in the normalized version of the phone number
+// remove_non_matches - indicates whether characters that are not able to be
+//   replaced should be stripped from the number. If this is false, they will be
+//   left unchanged in the number.
+void NormalizeHelper(const map<char32, char>& normalization_replacements,
+                     bool remove_non_matches,
+                     string* number) {
+  DCHECK(number);
+  UnicodeText number_as_unicode;
+  number_as_unicode.PointToUTF8(number->data(), number->size());
+  string normalized_number;
+  char unicode_char[5];
+  for (UnicodeText::const_iterator it = number_as_unicode.begin();
+       it != number_as_unicode.end();
+       ++it) {
+    map<char32, char>::const_iterator found_glyph_pair =
+        normalization_replacements.find(*it);
+    if (found_glyph_pair != normalization_replacements.end()) {
+      normalized_number.push_back(found_glyph_pair->second);
+    } else if (!remove_non_matches) {
+      // Find out how long this unicode char is so we can append it all.
+      int char_len = it.get_utf8(unicode_char);
+      normalized_number.append(unicode_char, char_len);
+    }
+    // If neither of the above are true, we remove this character.
+  }
+  number->assign(normalized_number);
+}
+
+// Strips the IDD from the start of the number if present. Helper function used
+// by MaybeStripInternationalPrefixAndNormalize.
+bool ParsePrefixAsIdd(const RegExp& idd_pattern, string* number) {
+  DCHECK(number);
+  const scoped_ptr<RegExpInput> number_copy(RegExpInput::Create(*number));
+  // First attempt to strip the idd_pattern at the start, if present. We make a
+  // copy so that we can revert to the original string if necessary.
+  if (idd_pattern.Consume(number_copy.get())) {
+    // Only strip this if the first digit after the match is not a 0, since
+    // country calling codes cannot begin with 0.
+    string extracted_digit;
+    if (capturing_digit_pattern->PartialMatch(number_copy->ToString(),
+                                              &extracted_digit)) {
+      PhoneNumberUtil::NormalizeDigitsOnly(&extracted_digit);
+      if (extracted_digit == "0") {
+        return false;
+      }
+    }
+    number->assign(number_copy->ToString());
+    return true;
+  }
+  return false;
+}
+
+PhoneNumberUtil::ValidationResult TestNumberLengthAgainstPattern(
+    const RegExp& number_pattern, const string& number) {
+  string extracted_number;
+  if (number_pattern.FullMatch(number, &extracted_number)) {
+    return PhoneNumberUtil::IS_POSSIBLE;
+  }
+  if (number_pattern.PartialMatch(number, &extracted_number)) {
+    return PhoneNumberUtil::TOO_LONG;
+  } else {
+    return PhoneNumberUtil::TOO_SHORT;
+  }
+}
+
+}  // namespace
+
+void PhoneNumberUtil::SetLogger(Logger* logger) {
+  Logger::set_logger_impl(logger);
+}
+
+// Private constructor. Also takes care of initialisation.
+PhoneNumberUtil::PhoneNumberUtil()
+    : country_calling_code_to_region_code_map_(new vector<IntRegionsPair>()),
+      nanpa_regions_(new set<string>()),
+      region_to_metadata_map_(new map<string, PhoneMetadata>()) {
+  logger_.reset(new StdoutLogger());
+  Logger::set_logger_impl(logger_.get());
+  PhoneMetadataCollection metadata_collection;
+  if (!LoadCompiledInMetadata(&metadata_collection)) {
+    LOG(DFATAL) << "Could not parse compiled-in metadata.";
+    return;
+  }
+  // Storing data in a temporary map to make it easier to find other regions
+  // that share a country calling code when inserting data.
+  map<int, list<string>* > country_calling_code_to_region_map;
+  for (RepeatedPtrField<PhoneMetadata>::const_iterator it =
+           metadata_collection.metadata().begin();
+       it != metadata_collection.metadata().end();
+       ++it) {
+    const PhoneMetadata& phone_metadata = *it;
+    const string& region_code = phone_metadata.id();
+    region_to_metadata_map_->insert(make_pair(region_code, *it));
+    int country_calling_code = it->country_code();
+    map<int, list<string>*>::iterator calling_code_in_map =
+        country_calling_code_to_region_map.find(country_calling_code);
+    if (calling_code_in_map != country_calling_code_to_region_map.end()) {
+      if (it->main_country_for_code()) {
+        calling_code_in_map->second->push_front(region_code);
+      } else {
+        calling_code_in_map->second->push_back(region_code);
+      }
+    } else {
+      // For most country calling codes, there will be only one region code.
+      list<string>* list_with_region_code = new list<string>();
+      list_with_region_code->push_back(region_code);
+      country_calling_code_to_region_map.insert(
+          make_pair(country_calling_code, list_with_region_code));
+    }
+    if (country_calling_code == kNanpaCountryCode) {
+        nanpa_regions_->insert(region_code);
+    }
+  }
+
+  country_calling_code_to_region_code_map_->insert(
+      country_calling_code_to_region_code_map_->begin(),
+      country_calling_code_to_region_map.begin(),
+      country_calling_code_to_region_map.end());
+  // Sort all the pairs in ascending order according to country calling code.
+  sort(country_calling_code_to_region_code_map_->begin(),
+       country_calling_code_to_region_code_map_->end(),
+       OrderByFirst());
+
+  InitializeStaticMapsAndSets();
+  CreateRegularExpressions();
+}
+
+PhoneNumberUtil::~PhoneNumberUtil() {
+  STLDeleteContainerPairSecondPointers(
+      country_calling_code_to_region_code_map_->begin(),
+      country_calling_code_to_region_code_map_->end());
+}
+
+// Public wrapper function to get a PhoneNumberUtil instance with the default
+// metadata file.
+// static
+PhoneNumberUtil* PhoneNumberUtil::GetInstance() {
+  return Singleton<PhoneNumberUtil>::get();
+}
+
+void PhoneNumberUtil::CreateRegularExpressions() const {
+  unique_international_prefix.reset(RegExp::Create(
+      "[\\d]+(?:[~\xE2\x81\x93\xE2\x88\xBC\xEF\xBD\x9E][\\d]+)?"));
+  // The first_group_capturing_pattern was originally set to $1 but there are
+  // some countries for which the first group is not used in the national
+  // pattern (e.g. Argentina) so the $1 group does not match correctly.
+  // Therefore, we use \d, so that the first group actually used in the pattern
+  // will be matched.
+  first_group_capturing_pattern.reset(RegExp::Create("(\\$\\d)"));
+  carrier_code_pattern.reset(RegExp::Create("\\$CC"));
+  digits_pattern.reset(RegExp::Create(StrCat("[", kDigits, "]*")));
+  capturing_digit_pattern.reset(RegExp::Create(StrCat("([", kDigits, "])")));
+  capturing_ascii_digits_pattern.reset(RegExp::Create("(\\d+)"));
+  valid_start_char.reset(new string(StrCat("[", kPlusChars, kDigits, "]")));
+  valid_start_char_pattern.reset(RegExp::Create(*valid_start_char));
+  capture_up_to_second_number_start_pattern.reset(RegExp::Create(
+      kCaptureUpToSecondNumberStart));
+  unwanted_end_char_pattern.reset(RegExp::Create(kUnwantedEndChar));
+  separator_pattern.reset(RegExp::Create(StrCat("[", kValidPunctuation, "]+")));
+  valid_phone_number.reset(new string(
+      StrCat("[", kPlusChars, "]*(?:[", kValidPunctuation, "]*[", kDigits,
+             "]){3,}[", kValidAlpha, kValidPunctuation, kDigits, "]*")));
+  // Canonical-equivalence doesn't seem to be an option with RE2, so we allow
+  // two options for representing the \xC3\xB3 - the character itself, and one in the
+  // unicode decomposed form with the combining acute accent. Note that there
+  // are currently three capturing groups for the extension itself - if this
+  // number is changed, MaybeStripExtension needs to be updated.
+  const string capturing_extn_digits = StrCat("([", kDigits, "]{1,7})");
+  known_extn_patterns.reset(new string(
+      StrCat(kRfc3966ExtnPrefix, capturing_extn_digits, "|"
+             "[ \xC2\xA0\\t,]*(?:ext(?:ensi(?:o\xCC\x81?|\xC3\xB3))?n?|\xEF\xBD\x85\xEF\xBD\x98\xEF\xBD\x94\xEF\xBD\x8E?|[,x\xEF\xBD\x98#\xEF\xBC\x83~\xEF\xBD\x9E]|"
+             "int|\xEF\xBD\x89\xEF\xBD\x8E\xEF\xBD\x94|anexo)"
+             "[:\\.\xEF\xBC\x8E]?[ \xC2\xA0\\t,-]*", capturing_extn_digits, "#?|"
+             "[- ]+([", kDigits, "]{1,5})#")));
+  extn_pattern.reset(RegExp::Create(
+      StrCat("(?i)(?:", *known_extn_patterns, ")$")));
+  valid_phone_number_pattern.reset(RegExp::Create(
+      StrCat("(?i)", *valid_phone_number, "(?:", *known_extn_patterns, ")?")));
+  valid_alpha_phone_pattern.reset(RegExp::Create(
+      StrCat("(?i)(?:.*?[", kValidAlpha, "]){3}")));
+  plus_chars_pattern.reset(RegExp::Create(StrCat("[", kPlusChars, "]+")));
+}
+
+const string& PhoneNumberUtil::GetExtnPatterns() const {
+  return *(known_extn_patterns.get());
+}
+
+void PhoneNumberUtil::TrimUnwantedEndChars(string* number) const {
+  DCHECK(number);
+  UnicodeText number_as_unicode;
+  number_as_unicode.PointToUTF8(number->data(), number->size());
+  char current_char[5];
+  int len;
+  UnicodeText::const_reverse_iterator reverse_it(number_as_unicode.end());
+  for (; reverse_it.base() != number_as_unicode.begin(); ++reverse_it) {
+    len = reverse_it.get_utf8(current_char);
+    current_char[len] = '\0';
+    if (!unwanted_end_char_pattern->FullMatch(current_char)) {
+      break;
+    }
+  }
+
+  number->assign(UnicodeText::UTF8Substring(number_as_unicode.begin(),
+                                            reverse_it.base()));
+}
+
+void PhoneNumberUtil::GetSupportedRegions(set<string>* regions) const {
+  DCHECK(regions);
+  for (map<string, PhoneMetadata>::const_iterator it =
+       region_to_metadata_map_->begin(); it != region_to_metadata_map_->end();
+       ++it) {
+    regions->insert(it->first);
+  }
+}
+
+void PhoneNumberUtil::GetNddPrefixForRegion(const string& region_code,
+                                            bool strip_non_digits,
+                                            string* national_prefix) const {
+  DCHECK(national_prefix);
+  if (!IsValidRegionCode(region_code)) {
+    LOG(ERROR) << "Invalid region code provided.";
+    return;
+  }
+  const PhoneMetadata* metadata = GetMetadataForRegion(region_code);
+  national_prefix->assign(metadata->national_prefix());
+  if (strip_non_digits) {
+    // Note: if any other non-numeric symbols are ever used in national
+    // prefixes, these would have to be removed here as well.
+    strrmm(national_prefix, "~");
+  }
+}
+
+bool PhoneNumberUtil::IsValidRegionCode(const string& region_code) const {
+  return (region_to_metadata_map_->find(region_code) !=
+          region_to_metadata_map_->end());
+}
+
+bool PhoneNumberUtil::HasValidRegionCode(const string& region_code,
+                                         int country_calling_code,
+                                         const string& number) const {
+  if (!IsValidRegionCode(region_code)) {
+    VLOG(1) << "Number " << number
+            << " has invalid or missing country calling code ("
+            << country_calling_code
+            << ")";
+    return false;
+  }
+  return true;
+}
+
+// Returns a pointer to the phone metadata for the appropriate region.
+const PhoneMetadata* PhoneNumberUtil::GetMetadataForRegion(
+    const string& region_code) const {
+  map<string, PhoneMetadata>::const_iterator it =
+      region_to_metadata_map_->find(region_code);
+  if (it != region_to_metadata_map_->end()) {
+    return &it->second;
+  }
+  return NULL;
+}
+
+void PhoneNumberUtil::Format(const PhoneNumber& number,
+                             PhoneNumberFormat number_format,
+                             string* formatted_number) const {
+  DCHECK(formatted_number);
+  int country_calling_code = number.country_code();
+  string national_significant_number;
+  GetNationalSignificantNumber(number, &national_significant_number);
+  if (number_format == E164) {
+    // Early exit for E164 case since no formatting of the national number needs
+    // to be applied. Extensions are not formatted.
+    FormatNumberByFormat(country_calling_code, E164,
+                         national_significant_number, "", formatted_number);
+    return;
+  }
+  // Note here that all NANPA formatting rules are contained by US, so we use
+  // that to format NANPA numbers. The same applies to Russian Fed regions -
+  // rules are contained by Russia. French Indian Ocean country rules are
+  // contained by R\xC3\xA9union.
+  string region_code;
+  GetRegionCodeForCountryCode(country_calling_code, &region_code);
+  if (!HasValidRegionCode(region_code, country_calling_code,
+                          national_significant_number)) {
+    formatted_number->assign(national_significant_number);
+    return;
+  }
+  string formatted_extension;
+  MaybeGetFormattedExtension(number, region_code, number_format,
+                             &formatted_extension);
+  string formatted_national_number;
+  FormatNationalNumber(national_significant_number, region_code, number_format,
+                       &formatted_national_number);
+  FormatNumberByFormat(country_calling_code, number_format,
+                       formatted_national_number,
+                       formatted_extension, formatted_number);
+}
+
+void PhoneNumberUtil::FormatByPattern(
+    const PhoneNumber& number,
+    PhoneNumberFormat number_format,
+    const RepeatedPtrField<NumberFormat>& user_defined_formats,
+    string* formatted_number) const {
+  DCHECK(formatted_number);
+  int country_calling_code = number.country_code();
+  // Note GetRegionCodeForCountryCode() is used because formatting information
+  // for regions which share a country calling code is contained by only one
+  // region for performance reasons. For example, for NANPA regions it will be
+  // contained in the metadata for US.
+  string region_code;
+  GetRegionCodeForCountryCode(country_calling_code, &region_code);
+  string national_significant_number;
+  GetNationalSignificantNumber(number, &national_significant_number);
+  if (!HasValidRegionCode(region_code, country_calling_code,
+                          national_significant_number)) {
+    formatted_number->assign(national_significant_number);
+    return;
+  }
+  RepeatedPtrField<NumberFormat> user_defined_formats_copy;
+  for (RepeatedPtrField<NumberFormat>::const_iterator it =
+           user_defined_formats.begin();
+       it != user_defined_formats.end();
+       ++it) {
+    string national_prefix_formatting_rule(
+        it->national_prefix_formatting_rule());
+    if (!national_prefix_formatting_rule.empty()) {
+      const string& national_prefix =
+          GetMetadataForRegion(region_code)->national_prefix();
+      NumberFormat* num_format_copy = user_defined_formats_copy.Add();
+      num_format_copy->MergeFrom(*it);
+      if (!national_prefix.empty()) {
+        // Replace $NP with national prefix and $FG with the first group ($1).
+        GlobalReplaceSubstring("$NP", national_prefix,
+                               &national_prefix_formatting_rule);
+        GlobalReplaceSubstring("$FG", "$1",
+                               &national_prefix_formatting_rule);
+        num_format_copy->set_national_prefix_formatting_rule(
+            national_prefix_formatting_rule);
+      } else {
+        // We don't want to have a rule for how to format the national prefix if
+        // there isn't one.
+        num_format_copy->clear_national_prefix_formatting_rule();
+      }
+    } else {
+      user_defined_formats_copy.Add()->MergeFrom(*it);
+    }
+  }
+  string formatted_number_without_extension;
+  FormatAccordingToFormats(national_significant_number,
+                           user_defined_formats_copy,
+                           number_format, national_significant_number,
+                           &formatted_number_without_extension);
+  string formatted_extension;
+  MaybeGetFormattedExtension(number, region_code, NATIONAL,
+                             &formatted_extension);
+  FormatNumberByFormat(country_calling_code, number_format,
+                       formatted_number_without_extension, formatted_extension,
+                       formatted_number);
+}
+
+void PhoneNumberUtil::FormatNationalNumberWithCarrierCode(
+    const PhoneNumber& number,
+    const string& carrier_code,
+    string* formatted_number) const {
+  int country_calling_code = number.country_code();
+  string national_significant_number;
+  GetNationalSignificantNumber(number, &national_significant_number);
+  // Note GetRegionCodeForCountryCode() is used because formatting information
+  // for regions which share a country calling code is contained by only one
+  // region for performance reasons. For example, for NANPA regions it will be
+  // contained in the metadata for US.
+  string region_code;
+  GetRegionCodeForCountryCode(country_calling_code, &region_code);
+  if (!HasValidRegionCode(region_code, country_calling_code,
+                          national_significant_number)) {
+    formatted_number->assign(national_significant_number);
+  }
+  string formatted_extension;
+  MaybeGetFormattedExtension(number, region_code, NATIONAL,
+                             &formatted_extension);
+  string formatted_national_number;
+  FormatNationalNumberWithCarrier(national_significant_number, region_code,
+                                  NATIONAL, carrier_code,
+                                  &formatted_national_number);
+  FormatNumberByFormat(country_calling_code, NATIONAL,
+                       formatted_national_number, formatted_extension,
+                       formatted_number);
+}
+
+void PhoneNumberUtil::FormatNationalNumberWithPreferredCarrierCode(
+    const PhoneNumber& number,
+    const string& fallback_carrier_code,
+    string* formatted_number) const {
+  FormatNationalNumberWithCarrierCode(
+      number,
+      number.has_preferred_domestic_carrier_code()
+          ? number.preferred_domestic_carrier_code()
+          : fallback_carrier_code,
+      formatted_number);
+}
+
+void PhoneNumberUtil::FormatOutOfCountryCallingNumber(
+    const PhoneNumber& number,
+    const string& calling_from,
+    string* formatted_number) const {
+  DCHECK(formatted_number);
+  if (!IsValidRegionCode(calling_from)) {
+    VLOG(1) << "Trying to format number from invalid region. International"
+            << " formatting applied.";
+    Format(number, INTERNATIONAL, formatted_number);
+    return;
+  }
+  int country_code = number.country_code();
+  string region_code;
+  GetRegionCodeForCountryCode(country_code, &region_code);
+  string national_significant_number;
+  GetNationalSignificantNumber(number, &national_significant_number);
+  if (!HasValidRegionCode(region_code, country_code,
+                          national_significant_number)) {
+    formatted_number->assign(national_significant_number);
+    return;
+  }
+  if (country_code == kNanpaCountryCode) {
+    if (IsNANPACountry(calling_from)) {
+      // For NANPA regions, return the national format for these regions but
+      // prefix it with the country calling code.
+      string national_number;
+      Format(number, NATIONAL, &national_number);
+      formatted_number->assign(StrCat(country_code, " ", national_number));
+      return;
+    }
+  } else if (country_code == GetCountryCodeForRegion(calling_from)) {
+    // If neither region is a NANPA region, then we check to see if the
+    // country calling code of the number and the country calling code of the
+    // region we are calling from are the same.
+    // For regions that share a country calling code, the country calling code
+    // need not be dialled. This also applies when dialling within a region, so
+    // this if clause covers both these cases.
+    // Technically this is the case for dialling from la R\xC3\xA9union to other
+    // overseas departments of France (French Guiana, Martinique, Guadeloupe),
+    // but not vice versa - so we don't cover this edge case for now and for
+    // those cases return the version including country calling code.
+    // Details here:
+    // http://www.petitfute.com/voyage/225-info-pratiques-reunion
+    Format(number, NATIONAL, formatted_number);
+    return;
+  }
+  string formatted_national_number;
+  FormatNationalNumber(national_significant_number, region_code, INTERNATIONAL,
+                       &formatted_national_number);
+  const PhoneMetadata* metadata = GetMetadataForRegion(calling_from);
+  const string& international_prefix = metadata->international_prefix();
+  string formatted_extension;
+  MaybeGetFormattedExtension(number, region_code, INTERNATIONAL,
+                             &formatted_extension);
+  // For regions that have multiple international prefixes, the international
+  // format of the number is returned, unless there is a preferred international
+  // prefix.
+  const string international_prefix_for_formatting(
+      unique_international_prefix->FullMatch(international_prefix)
+      ? international_prefix
+      : metadata->preferred_international_prefix());
+  if (!international_prefix_for_formatting.empty()) {
+    formatted_number->assign(
+        StrCat(international_prefix_for_formatting, " ", country_code, " ",
+               formatted_national_number, formatted_extension));
+  } else {
+    FormatNumberByFormat(country_code, INTERNATIONAL, formatted_national_number,
+                         formatted_extension, formatted_number);
+  }
+}
+
+void PhoneNumberUtil::FormatInOriginalFormat(const PhoneNumber& number,
+                                             const string& region_calling_from,
+                                             string* formatted_number) const {
+  DCHECK(formatted_number);
+
+  if (!number.has_country_code_source()) {
+    Format(number, NATIONAL, formatted_number);
+    return;
+  }
+  switch (number.country_code_source()) {
+    case PhoneNumber::FROM_NUMBER_WITH_PLUS_SIGN:
+      Format(number, INTERNATIONAL, formatted_number);
+      return;
+    case PhoneNumber::FROM_NUMBER_WITH_IDD:
+      FormatOutOfCountryCallingNumber(number, region_calling_from,
+                                      formatted_number);
+      return;
+    case PhoneNumber::FROM_NUMBER_WITHOUT_PLUS_SIGN:
+      Format(number, INTERNATIONAL, formatted_number);
+      formatted_number->erase(formatted_number->begin());
+      return;
+    case PhoneNumber::FROM_DEFAULT_COUNTRY:
+    default:
+      Format(number, NATIONAL, formatted_number);
+  }
+}
+
+void PhoneNumberUtil::FormatOutOfCountryKeepingAlphaChars(
+    const PhoneNumber& number,
+    const string& calling_from,
+    string* formatted_number) const {
+  // If there is no raw input, then we can't keep alpha characters because there
+  // aren't any. In this case, we return FormatOutOfCountryCallingNumber.
+  if (number.raw_input().empty()) {
+    FormatOutOfCountryCallingNumber(number, calling_from, formatted_number);
+    return;
+  }
+  string region_code;
+  GetRegionCodeForCountryCode(number.country_code(), &region_code);
+  if (!HasValidRegionCode(region_code, number.country_code(),
+                          number.raw_input())) {
+    formatted_number->assign(number.raw_input());
+    return;
+  }
+  // Strip any prefix such as country calling code, IDD, that was present. We do
+  // this by comparing the number in raw_input with the parsed number.
+  string raw_input_copy(number.raw_input());
+  // Normalize punctuation. We retain number grouping symbols such as " " only.
+  NormalizeHelper(*all_plus_number_grouping_symbols, true, &raw_input_copy);
+  // Now we trim everything before the first three digits in the parsed number.
+  // We choose three because all valid alpha numbers have 3 digits at the start
+  // - if it does not, then we don't trim anything at all. Similarly, if the
+  // national number was less than three digits, we don't trim anything at all.
+  string national_number;
+  GetNationalSignificantNumber(number, &national_number);
+  if (national_number.length() > 3) {
+    size_t first_national_number_digit =
+        raw_input_copy.find(national_number.substr(0, 3));
+    if (first_national_number_digit != string::npos) {
+      raw_input_copy = raw_input_copy.substr(first_national_number_digit);
+    }
+  }
+  const PhoneMetadata* metadata = GetMetadataForRegion(calling_from);
+  if (number.country_code() == kNanpaCountryCode) {
+    if (IsNANPACountry(calling_from)) {
+      formatted_number->assign(StrCat(number.country_code(), " ",
+                                      raw_input_copy));
+      return;
+    }
+  } else if (number.country_code() == GetCountryCodeForRegion(calling_from)) {
+    // Here we copy the formatting rules so we can modify the pattern we expect
+    // to match against.
+    RepeatedPtrField<NumberFormat> available_formats =
+        metadata->number_format();
+    for (RepeatedPtrField<NumberFormat>::iterator
+         it = available_formats.begin(); it != available_formats.end(); ++it) {
+      // The first group is the first group of digits that the user determined.
+      it->set_pattern("(\\d+)(.*)");
+      // Here we just concatenate them back together after the national prefix
+      // has been fixed.
+      it->set_format("$1$2");
+    }
+    // Now we format using these patterns instead of the default pattern, but
+    // with the national prefix prefixed if necessary, by choosing the format
+    // rule based on the leading digits present in the unformatted national
+    // number.
+    // This will not work in the cases where the pattern (and not the
+    // leading digits) decide whether a national prefix needs to be used, since
+    // we have overridden the pattern to match anything, but that is not the
+    // case in the metadata to date.
+    FormatAccordingToFormats(national_number, available_formats,
+                             NATIONAL, raw_input_copy, formatted_number);
+    return;
+  }
+
+  const string& international_prefix = metadata->international_prefix();
+  // For regions that have multiple international prefixes, the international
+  // format of the number is returned, unless there is a preferred international
+  // prefix.
+  const string international_prefix_for_formatting(
+      unique_international_prefix->FullMatch(international_prefix)
+      ? international_prefix
+      : metadata->preferred_international_prefix());
+  if (!international_prefix_for_formatting.empty()) {
+    formatted_number->assign(
+        StrCat(international_prefix_for_formatting, " ", number.country_code(),
+               " ", raw_input_copy));
+  } else {
+    FormatNumberByFormat(number.country_code(), INTERNATIONAL, raw_input_copy,
+                         "", formatted_number);
+  }
+}
+
+void PhoneNumberUtil::FormatNationalNumber(
+    const string& number,
+    const string& region_code,
+    PhoneNumberFormat number_format,
+    string* formatted_number) const {
+  DCHECK(formatted_number);
+  FormatNationalNumberWithCarrier(number, region_code, number_format, "",
+                                  formatted_number);
+}
+
+// Note in some regions, the national number can be written in two completely
+// different ways depending on whether it forms part of the NATIONAL format or
+// INTERNATIONAL format. The number_format parameter here is used to specify
+// which format to use for those cases. If a carrier_code is specified, this
+// will be inserted into the formatted string to replace $CC.
+void PhoneNumberUtil::FormatNationalNumberWithCarrier(
+    const string& number,
+    const string& region_code,
+    PhoneNumberFormat number_format,
+    const string& carrier_code,
+    string* formatted_number) const {
+  DCHECK(formatted_number);
+  const PhoneMetadata* metadata = GetMetadataForRegion(region_code);
+  // When the intl_number_formats exists, we use that to format national number
+  // for the INTERNATIONAL format instead of using the number_formats.
+  const RepeatedPtrField<NumberFormat> available_formats =
+      (metadata->intl_number_format_size() == 0 || number_format == NATIONAL)
+      ? metadata->number_format()
+      : metadata->intl_number_format();
+  FormatAccordingToFormatsWithCarrier(number, available_formats, number_format,
+                                      number, carrier_code, formatted_number);
+  if (number_format == RFC3966) {
+    // Replace all separators with a "-".
+    separator_pattern->GlobalReplace(formatted_number, "-");
+  }
+}
+
+// Gets the formatted extension of a phone number, if the phone number had an
+// extension specified. If not, it returns an empty string.
+void PhoneNumberUtil::MaybeGetFormattedExtension(
+    const PhoneNumber& number,
+    const string& region_code,
+    PhoneNumberFormat number_format,
+    string* extension) const {
+  DCHECK(extension);
+  if (!number.has_extension() || number.extension().length() == 0) {
+    extension->assign("");
+  } else {
+    if (number_format == RFC3966) {
+      StrAppend(extension, kRfc3966ExtnPrefix, number.extension());
+      return;
+    }
+    FormatExtension(number.extension(), region_code, extension);
+  }
+}
+
+// Formats the extension part of the phone number by prefixing it with the
+// appropriate extension prefix. This will be the default extension prefix,
+// unless overridden by a preferred extension prefix for this region.
+void PhoneNumberUtil::FormatExtension(const string& extension_digits,
+                                      const string& region_code,
+                                      string* extension) const {
+  DCHECK(extension);
+  const PhoneMetadata* metadata = GetMetadataForRegion(region_code);
+  if (metadata->has_preferred_extn_prefix()) {
+    extension->assign(StrCat(metadata->preferred_extn_prefix(),
+                             extension_digits));
+  } else {
+    extension->assign(StrCat(kDefaultExtnPrefix, extension_digits));
+  }
+}
+
+bool PhoneNumberUtil::IsNANPACountry(const string& region_code) const {
+  return nanpa_regions_->find(region_code) != nanpa_regions_->end();
+}
+
+// Returns the region codes that matches the specific country calling code. In
+// the case of no region code being found, region_codes will be left empty.
+void PhoneNumberUtil::GetRegionCodesForCountryCallingCode(
+    int country_calling_code,
+    list<string>* region_codes) const {
+  DCHECK(region_codes);
+  // Create a IntRegionsPair with the country_code passed in, and use it to
+  // locate the pair with the same country_code in the sorted vector.
+  IntRegionsPair target_pair;
+  target_pair.first = country_calling_code;
+  typedef vector<IntRegionsPair>::const_iterator ConstIterator;
+  pair<ConstIterator, ConstIterator> range = equal_range(
+      country_calling_code_to_region_code_map_->begin(),
+      country_calling_code_to_region_code_map_->end(),
+      target_pair, OrderByFirst());
+  if (range.first != range.second) {
+    region_codes->insert(region_codes->begin(),
+                         range.first->second->begin(),
+                         range.first->second->end());
+  }
+}
+
+// Returns the region code that matches the specific country calling code. In
+// the case of no region code being found, ZZ will be returned.
+void PhoneNumberUtil::GetRegionCodeForCountryCode(
+    int country_calling_code,
+    string* region_code) const {
+  DCHECK(region_code);
+  list<string> region_codes;
+
+  GetRegionCodesForCountryCallingCode(country_calling_code, &region_codes);
+  *region_code = (region_codes.size() > 0)
+      ? region_codes.front() : RegionCode::GetUnknown();
+}
+
+void PhoneNumberUtil::GetRegionCodeForNumber(const PhoneNumber& number,
+                                             string* region_code) const {
+  DCHECK(region_code);
+  int country_calling_code = number.country_code();
+  list<string> region_codes;
+  GetRegionCodesForCountryCallingCode(country_calling_code, &region_codes);
+  if (region_codes.size() == 0) {
+    string number_string;
+    GetNationalSignificantNumber(number, &number_string);
+    LOG(WARNING) << "Missing/invalid country calling code ("
+                 << country_calling_code
+                 << ") for number " << number_string;
+    *region_code = RegionCode::GetUnknown();
+    return;
+  }
+  if (region_codes.size() == 1) {
+    *region_code = region_codes.front();
+  } else {
+    GetRegionCodeForNumberFromRegionList(number, region_codes, region_code);
+  }
+}
+
+void PhoneNumberUtil::GetRegionCodeForNumberFromRegionList(
+    const PhoneNumber& number, const list<string>& region_codes,
+    string* region_code) const {
+  DCHECK(region_code);
+  string national_number;
+  GetNationalSignificantNumber(number, &national_number);
+  for (list<string>::const_iterator it = region_codes.begin();
+       it != region_codes.end(); ++it) {
+    const PhoneMetadata* metadata = GetMetadataForRegion(*it);
+    if (metadata->has_leading_digits()) {
+      const scoped_ptr<RegExpInput> number(
+          RegExpInput::Create(national_number));
+      if (regexp_cache->GetRegExp(metadata->leading_digits()).Consume(
+          number.get())) {
+        *region_code = *it;
+        return;
+      }
+    } else if (GetNumberTypeHelper(national_number, *metadata) != UNKNOWN) {
+      *region_code = *it;
+      return;
+    }
+  }
+  *region_code = RegionCode::GetUnknown();
+}
+
+int PhoneNumberUtil::GetCountryCodeForRegion(const string& region_code) const {
+  if (!IsValidRegionCode(region_code)) {
+    LOG(ERROR) << "Invalid or unknown region code provided.";
+    return 0;
+  }
+  const PhoneMetadata* metadata = GetMetadataForRegion(region_code);
+  return metadata->country_code();
+}
+
+// Gets a valid fixed-line number for the specified region_code. Returns false
+// if the country was unknown or if no number exists.
+bool PhoneNumberUtil::GetExampleNumber(const string& region_code,
+                                       PhoneNumber* number) const {
+  DCHECK(number);
+  return GetExampleNumberForType(region_code,
+                                 FIXED_LINE,
+                                 number);
+}
+
+// Gets a valid number for the specified region_code and type.  Returns false if
+// the country was unknown or if no number exists.
+bool PhoneNumberUtil::GetExampleNumberForType(
+    const string& region_code,
+    PhoneNumberUtil::PhoneNumberType type,
+    PhoneNumber* number) const {
+  DCHECK(number);
+  if (!IsValidRegionCode(region_code)) {
+    LOG(WARNING) << "Invalid or unknown region code provided.";
+    return false;
+  }
+  const PhoneMetadata* region_metadata = GetMetadataForRegion(region_code);
+  const PhoneNumberDesc* description =
+      GetNumberDescByType(*region_metadata, type);
+  if (description && description->has_example_number()) {
+    return (Parse(description->example_number(),
+                  region_code,
+                  number) == NO_PARSING_ERROR);
+  }
+  return false;
+}
+
+PhoneNumberUtil::ErrorType PhoneNumberUtil::Parse(const string& number_to_parse,
+                                                  const string& default_region,
+                                                  PhoneNumber* number) const {
+  DCHECK(number);
+  return ParseHelper(number_to_parse, default_region, false, true, number);
+}
+
+PhoneNumberUtil::ErrorType PhoneNumberUtil::ParseAndKeepRawInput(
+    const string& number_to_parse,
+    const string& default_region,
+    PhoneNumber* number) const {
+  DCHECK(number);
+  return ParseHelper(number_to_parse, default_region, true, true, number);
+}
+
+// Checks to see that the region code used is valid, or if it is not valid, that
+// the number to parse starts with a + symbol so that we can attempt to infer
+// the country from the number. Returns false if it cannot use the region
+// provided and the region cannot be inferred.
+bool PhoneNumberUtil::CheckRegionForParsing(
+    const string& number_to_parse,
+    const string& default_region) const {
+  if (!IsValidRegionCode(default_region) && !number_to_parse.empty()) {
+    const scoped_ptr<RegExpInput> number(RegExpInput::Create(number_to_parse));
+    if (!plus_chars_pattern->Consume(number.get())) {
+      return false;
+    }
+  }
+  return true;
+}
+
+PhoneNumberUtil::ErrorType PhoneNumberUtil::ParseHelper(
+    const string& number_to_parse,
+    const string& default_region,
+    bool keep_raw_input,
+    bool check_region,
+    PhoneNumber* phone_number) const {
+  DCHECK(phone_number);
+  // Extract a possible number from the string passed in (this strips leading
+  // characters that could not be the start of a phone number.)
+  string national_number;
+  ExtractPossibleNumber(number_to_parse, &national_number);
+  if (!IsViablePhoneNumber(national_number)) {
+    VLOG(2) << "The string supplied did not seem to be a phone number.";
+    return NOT_A_NUMBER;
+  }
+
+  if (check_region &&
+      !CheckRegionForParsing(national_number, default_region)) {
+    VLOG(1) << "Missing or invalid default country.";
+    return INVALID_COUNTRY_CODE_ERROR;
+  }
+  PhoneNumber temp_number;
+  if (keep_raw_input) {
+    temp_number.set_raw_input(number_to_parse);
+  }
+  // Attempt to parse extension first, since it doesn't require country-specific
+  // data and we want to have the non-normalised number here.
+  string extension;
+  MaybeStripExtension(&national_number, &extension);
+  if (!extension.empty()) {
+    temp_number.set_extension(extension);
+  }
+  const PhoneMetadata* country_metadata = GetMetadataForRegion(default_region);
+  // Check to see if the number is given in international format so we know
+  // whether this number is from the default country or not.
+  string normalized_national_number(national_number);
+  ErrorType country_code_error =
+      MaybeExtractCountryCode(country_metadata, keep_raw_input,
+                              &normalized_national_number, &temp_number);
+  int country_code = temp_number.country_code();
+  if (country_code_error != NO_PARSING_ERROR) {
+    return country_code_error;
+  }
+  if (country_code != 0) {
+    string phone_number_region;
+    GetRegionCodeForCountryCode(country_code, &phone_number_region);
+    if (phone_number_region != default_region) {
+      country_metadata = GetMetadataForRegion(phone_number_region);
+    }
+  } else if (country_metadata) {
+    // If no extracted country calling code, use the region supplied instead.
+    // Note that the national number was already normalized by
+    // MaybeExtractCountryCode.
+    country_code = country_metadata->country_code();
+  }
+  if (normalized_national_number.length() < kMinLengthForNsn) {
+    VLOG(2) << "The string supplied is too short to be a phone number.";
+    return TOO_SHORT_NSN;
+  }
+  if (country_metadata) {
+    string* carrier_code = keep_raw_input ?
+        temp_number.mutable_preferred_domestic_carrier_code() : NULL;
+    MaybeStripNationalPrefixAndCarrierCode(*country_metadata,
+                                           &normalized_national_number,
+                                           carrier_code);
+  }
+  size_t normalized_national_number_length =
+      normalized_national_number.length();
+  if (normalized_national_number_length < kMinLengthForNsn) {
+    VLOG(2) << "The string supplied is too short to be a phone number.";
+    return TOO_SHORT_NSN;
+  }
+  if (normalized_national_number_length > kMaxLengthForNsn) {
+    VLOG(2) << "The string supplied is too long to be a phone number.";
+    return TOO_LONG_NSN;
+  }
+  temp_number.set_country_code(country_code);
+  if (country_metadata &&
+      country_metadata->leading_zero_possible() &&
+      normalized_national_number[0] == '0') {
+    temp_number.set_italian_leading_zero(true);
+  }
+  uint64 number_as_int;
+  safe_strtou64(normalized_national_number, &number_as_int);
+  temp_number.set_national_number(number_as_int);
+  phone_number->MergeFrom(temp_number);
+  return NO_PARSING_ERROR;
+}
+
+// Attempts to extract a possible number from the string passed in. This
+// currently strips all leading characters that could not be used to start a
+// phone number. Characters that can be used to start a phone number are
+// defined in the valid_start_char_pattern. If none of these characters are
+// found in the number passed in, an empty string is returned. This function
+// also attempts to strip off any alternative extensions or endings if two or
+// more are present, such as in the case of: (530) 583-6985 x302/x2303. The
+// second extension here makes this actually two phone numbers, (530) 583-6985
+// x302 and (530) 583-6985 x2303. We remove the second extension so that the
+// first number is parsed correctly.
+void PhoneNumberUtil::ExtractPossibleNumber(const string& number,
+                                            string* extracted_number) const {
+  DCHECK(extracted_number);
+
+  UnicodeText number_as_unicode;
+  number_as_unicode.PointToUTF8(number.data(), number.size());
+  char current_char[5];
+  int len;
+  UnicodeText::const_iterator it;
+  for (it = number_as_unicode.begin(); it != number_as_unicode.end(); ++it) {
+    len = it.get_utf8(current_char);
+    current_char[len] = '\0';
+    if (valid_start_char_pattern->FullMatch(current_char)) {
+      break;
+    }
+  }
+
+  if (it == number_as_unicode.end()) {
+    // No valid start character was found. extracted_number should be set to
+    // empty string.
+    extracted_number->assign("");
+    return;
+  }
+
+  extracted_number->assign(
+      UnicodeText::UTF8Substring(it, number_as_unicode.end()));
+  TrimUnwantedEndChars(extracted_number);
+  if (extracted_number->length() == 0) {
+    return;
+  }
+
+  VLOG(3) << "After stripping starting and trailing characters, left with: "
+          << *extracted_number;
+
+  // Now remove any extra numbers at the end.
+  capture_up_to_second_number_start_pattern->PartialMatch(*extracted_number,
+                                                          extracted_number);
+}
+
+bool PhoneNumberUtil::IsPossibleNumber(const PhoneNumber& number) const {
+  return IsPossibleNumberWithReason(number) == IS_POSSIBLE;
+}
+
+bool PhoneNumberUtil::IsPossibleNumberForString(
+    const string& number,
+    const string& region_dialing_from) const {
+  PhoneNumber number_proto;
+  if (Parse(number, region_dialing_from, &number_proto) == NO_PARSING_ERROR) {
+    return IsPossibleNumber(number_proto);
+  } else {
+    return false;
+  }
+}
+
+PhoneNumberUtil::ValidationResult PhoneNumberUtil::IsPossibleNumberWithReason(
+    const PhoneNumber& number) const {
+  string national_number;
+  GetNationalSignificantNumber(number, &national_number);
+  int country_code = number.country_code();
+  // Note: For Russian Fed and NANPA numbers, we just use the rules from the
+  // default region (US or Russia) since the GetRegionCodeForNumber will not
+  // work if the number is possible but not valid. This would need to be
+  // revisited if the possible number pattern ever differed between various
+  // regions within those plans.
+  string region_code;
+  GetRegionCodeForCountryCode(country_code, &region_code);
+  if (!HasValidRegionCode(region_code, country_code, national_number)) {
+    return INVALID_COUNTRY_CODE;
+  }
+  const PhoneNumberDesc& general_num_desc =
+      GetMetadataForRegion(region_code)->general_desc();
+  // Handling case of numbers with no metadata.
+  if (!general_num_desc.has_national_number_pattern()) {
+    size_t number_length = national_number.length();
+    if (number_length < kMinLengthForNsn) {
+      return TOO_SHORT;
+    } else if (number_length > kMaxLengthForNsn) {
+      return TOO_LONG;
+    } else {
+      return IS_POSSIBLE;
+    }
+  }
+  const RegExp& possible_number_pattern = regexp_cache->GetRegExp(
+      StrCat("(", general_num_desc.possible_number_pattern(), ")"));
+  return TestNumberLengthAgainstPattern(possible_number_pattern,
+                                        national_number);
+}
+
+bool PhoneNumberUtil::TruncateTooLongNumber(PhoneNumber* number) const {
+  if (IsValidNumber(*number)) {
+    return true;
+  }
+  PhoneNumber number_copy(*number);
+  uint64 national_number = number->national_number();
+  do {
+    national_number /= 10;
+    number_copy.set_national_number(national_number);
+    if (IsPossibleNumberWithReason(number_copy) == TOO_SHORT ||
+        national_number == 0) {
+      return false;
+    }
+  } while (!IsValidNumber(number_copy));
+  number->set_national_number(national_number);
+  return true;
+}
+
+PhoneNumberUtil::PhoneNumberType PhoneNumberUtil::GetNumberType(
+    const PhoneNumber& number) const {
+  string region_code;
+  GetRegionCodeForNumber(number, &region_code);
+  if (!IsValidRegionCode(region_code)) {
+    return UNKNOWN;
+  }
+  string national_significant_number;
+  GetNationalSignificantNumber(number, &national_significant_number);
+  return GetNumberTypeHelper(national_significant_number,
+                             *GetMetadataForRegion(region_code));
+}
+
+bool PhoneNumberUtil::IsValidNumber(const PhoneNumber& number) const {
+  string region_code;
+  GetRegionCodeForNumber(number, &region_code);
+  return IsValidRegionCode(region_code) &&
+      IsValidNumberForRegion(number, region_code);
+}
+
+bool PhoneNumberUtil::IsValidNumberForRegion(const PhoneNumber& number,
+                                             const string& region_code) const {
+  if (number.country_code() != GetCountryCodeForRegion(region_code)) {
+    return false;
+  }
+  const PhoneMetadata* metadata = GetMetadataForRegion(region_code);
+  const PhoneNumberDesc& general_desc = metadata->general_desc();
+  string national_number;
+  GetNationalSignificantNumber(number, &national_number);
+
+  // For regions where we don't have metadata for PhoneNumberDesc, we treat
+  // any number passed in as a valid number if its national significant number
+  // is between the minimum and maximum lengths defined by ITU for a national
+  // significant number.
+  if (!general_desc.has_national_number_pattern()) {
+    VLOG(3) << "Validating number with incomplete metadata.";
+    size_t number_length = national_number.length();
+    return number_length > kMinLengthForNsn &&
+        number_length <= kMaxLengthForNsn;
+  }
+  return GetNumberTypeHelper(national_number, *metadata) != UNKNOWN;
+}
+
+bool PhoneNumberUtil::IsLeadingZeroPossible(int country_calling_code) const {
+  string region_code;
+  GetRegionCodeForCountryCode(country_calling_code, &region_code);
+  const PhoneMetadata* main_metadata_for_calling_code =
+      GetMetadataForRegion(region_code);
+  if (!main_metadata_for_calling_code) return false;
+  return main_metadata_for_calling_code->leading_zero_possible();
+}
+
+void PhoneNumberUtil::GetNationalSignificantNumber(
+    const PhoneNumber& number,
+    string* national_number) const {
+  // The leading zero in the national (significant) number of an Italian phone
+  // number has a special meaning. Unlike the rest of the world, it indicates
+  // the number is a landline number. There have been plans to migrate landline
+  // numbers to start with the digit two since December 2000, but it has not yet
+  // happened.
+  // See http://en.wikipedia.org/wiki/%2B39 for more details.
+  // Other regions such as Cote d'Ivoire and Gabon use this for their mobile
+  // numbers.
+  DCHECK(national_number);
+  StrAppend(national_number,
+      (IsLeadingZeroPossible(number.country_code()) &&
+       number.has_italian_leading_zero() &&
+       number.italian_leading_zero())
+      ? "0"
+      : "");
+  StrAppend(national_number, number.national_number());
+}
+
+int PhoneNumberUtil::GetLengthOfGeographicalAreaCode(
+    const PhoneNumber& number) const {
+  string region_code;
+  GetRegionCodeForNumber(number, &region_code);
+  if (!IsValidRegionCode(region_code)) {
+    return 0;
+  }
+  const PhoneMetadata* metadata = GetMetadataForRegion(region_code);
+  DCHECK(metadata);
+  if (!metadata->has_national_prefix()) {
+    return 0;
+  }
+
+  string national_significant_number;
+  GetNationalSignificantNumber(number, &national_significant_number);
+  PhoneNumberType type = GetNumberTypeHelper(national_significant_number,
+                                             *metadata);
+  // Most numbers other than the two types below have to be dialled in full.
+  if (type != FIXED_LINE && type != FIXED_LINE_OR_MOBILE) {
+    return 0;
+  }
+
+  return GetLengthOfNationalDestinationCode(number);
+}
+
+int PhoneNumberUtil::GetLengthOfNationalDestinationCode(
+    const PhoneNumber& number) const {
+  PhoneNumber copied_proto(number);
+  if (number.has_extension()) {
+    // Clear the extension so it's not included when formatting.
+    copied_proto.clear_extension();
+  }
+
+  string formatted_number;
+  Format(copied_proto, INTERNATIONAL, &formatted_number);
+  const scoped_ptr<RegExpInput> i18n_number(
+      RegExpInput::Create(formatted_number));
+  string digit_group;
+  string ndc;
+  string third_group;
+  for (int i = 0; i < 3; ++i) {
+    if (!capturing_ascii_digits_pattern->FindAndConsume(i18n_number.get(),
+                                                        &digit_group)) {
+      // We should find at least three groups.
+      return 0;
+    }
+    if (i == 1) {
+      ndc = digit_group;
+    } else if (i == 2) {
+      third_group = digit_group;
+    }
+  }
+  string region_code;
+  GetRegionCodeForNumber(number, &region_code);
+  if (region_code == "AR" &&
+      GetNumberType(number) == MOBILE) {
+    // Argentinian mobile numbers, when formatted in the international format,
+    // are in the form of +54 9 NDC XXXX.... As a result, we take the length of
+    // the third group (NDC) and add 1 for the digit 9, which also forms part of
+    // the national significant number.
+    return third_group.size() + 1;
+  }
+  return ndc.size();
+}
+
+// static
+void PhoneNumberUtil::NormalizeDigitsOnly(string* number) {
+  DCHECK(number);
+  static const scoped_ptr<const RegExp> non_digits_pattern(RegExp::Create(
+      StrCat("[^", kDigits, "]")));
+  // Delete everything that isn't valid digits.
+  non_digits_pattern->GlobalReplace(number, "");
+  // Normalize all decimal digits to ASCII digits.
+  number->assign(NormalizeUTF8::NormalizeDecimalDigits(*number));
+}
+
+bool PhoneNumberUtil::IsAlphaNumber(const string& number) const {
+  if (!IsViablePhoneNumber(number)) {
+    // Number is too short, or doesn't match the basic phone number pattern.
+    return false;
+  }
+  // Copy the number, since we are going to try and strip the extension from it.
+  string number_copy(number);
+  string extension;
+  MaybeStripExtension(&number_copy, &extension);
+  return valid_alpha_phone_pattern->FullMatch(number_copy);
+}
+
+void PhoneNumberUtil::ConvertAlphaCharactersInNumber(string* number) const {
+  DCHECK(number);
+  NormalizeHelper(*alpha_phone_mappings, false, number);
+}
+
+// Normalizes a string of characters representing a phone number. This performs
+// the following conversions:
+//   - Punctuation is stripped.
+//   For ALPHA/VANITY numbers:
+//   - Letters are converted to their numeric representation on a telephone
+//     keypad. The keypad used here is the one defined in ITU Recommendation
+//     E.161. This is only done if there are 3 or more letters in the number, to
+//     lessen the risk that such letters are typos.
+//   For other numbers:
+//   - Wide-ascii digits are converted to normal ASCII (European) digits.
+//   - Arabic-Indic numerals are converted to European numerals.
+//   - Spurious alpha characters are stripped.
+void PhoneNumberUtil::Normalize(string* number) const {
+  DCHECK(number);
+  if (valid_alpha_phone_pattern->PartialMatch(*number)) {
+    NormalizeHelper(*alpha_phone_mappings, true, number);
+  }
+  NormalizeDigitsOnly(number);
+}
+
+// Checks to see if the string of characters could possibly be a phone number at
+// all. At the moment, checks to see that the string begins with at least 3
+// digits, ignoring any punctuation commonly found in phone numbers.  This
+// method does not require the number to be normalized in advance - but does
+// assume that leading non-number symbols have been removed, such as by the
+// method ExtractPossibleNumber.
+bool PhoneNumberUtil::IsViablePhoneNumber(const string& number) const {
+  if (number.length() < kMinLengthForNsn) {
+    VLOG(2) << "Number too short to be viable:" << number;
+    return false;
+  }
+  return valid_phone_number_pattern->FullMatch(number);
+}
+
+// Strips any international prefix (such as +, 00, 011) present in the number
+// provided, normalizes the resulting number, and indicates if an international
+// prefix was present.
+//
+// possible_idd_prefix represents the international direct dialing prefix from
+// the region we think this number may be dialed in.
+// Returns true if an international dialing prefix could be removed from the
+// number, otherwise false if the number did not seem to be in international
+// format.
+PhoneNumber::CountryCodeSource
+PhoneNumberUtil::MaybeStripInternationalPrefixAndNormalize(
+    const string& possible_idd_prefix,
+    string* number) const {
+  DCHECK(number);
+  if (number->empty()) {
+    return PhoneNumber::FROM_DEFAULT_COUNTRY;
+  }
+  const scoped_ptr<RegExpInput> number_string_piece(
+      RegExpInput::Create(*number));
+  if (plus_chars_pattern->Consume(number_string_piece.get())) {
+    number->assign(number_string_piece->ToString());
+    // Can now normalize the rest of the number since we've consumed the "+"
+    // sign at the start.
+    Normalize(number);
+    return PhoneNumber::FROM_NUMBER_WITH_PLUS_SIGN;
+  }
+  // Attempt to parse the first digits as an international prefix.
+  const RegExp& idd_pattern = regexp_cache->GetRegExp(possible_idd_prefix);
+  if (ParsePrefixAsIdd(idd_pattern, number)) {
+    Normalize(number);
+    return PhoneNumber::FROM_NUMBER_WITH_IDD;
+  }
+  // If still not found, then try and normalize the number and then try again.
+  // This shouldn't be done before, since non-numeric characters (+ and ~) may
+  // legally be in the international prefix.
+  Normalize(number);
+  return ParsePrefixAsIdd(idd_pattern, number)
+      ? PhoneNumber::FROM_NUMBER_WITH_IDD
+      : PhoneNumber::FROM_DEFAULT_COUNTRY;
+}
+
+// Strips any national prefix (such as 0, 1) present in the number provided.
+// The number passed in should be the normalized telephone number that we wish
+// to strip any national dialing prefix from. The metadata should be for the
+// region that we think this number is from.
+void PhoneNumberUtil::MaybeStripNationalPrefixAndCarrierCode(
+    const PhoneMetadata& metadata,
+    string* number,
+    string* carrier_code) const {
+  DCHECK(number);
+  string carrier_code_temp;
+  const string& possible_national_prefix =
+      metadata.national_prefix_for_parsing();
+  if (number->empty() || possible_national_prefix.empty()) {
+    // Early return for numbers of zero length or with no national prefix
+    // possible.
+    return;
+  }
+  // We use two copies here since Consume modifies the phone number, and if the
+  // first if-clause fails the number will already be changed.
+  const scoped_ptr<RegExpInput> number_copy(RegExpInput::Create(*number));
+  const scoped_ptr<RegExpInput> number_copy_without_transform(
+      RegExpInput::Create(*number));
+  string number_string_copy(*number);
+  string captured_part_of_prefix;
+  const RegExp& national_number_rule = regexp_cache->GetRegExp(
+      metadata.general_desc().national_number_pattern());
+  // Attempt to parse the first digits as a national prefix. We make a
+  // copy so that we can revert to the original string if necessary.
+  const string& transform_rule = metadata.national_prefix_transform_rule();
+  const RegExp& possible_national_prefix_pattern =
+      regexp_cache->GetRegExp(possible_national_prefix);
+  if (!transform_rule.empty() &&
+      (possible_national_prefix_pattern.Consume(
+          number_copy.get(), &carrier_code_temp, &captured_part_of_prefix) ||
+       possible_national_prefix_pattern.Consume(
+           number_copy.get(), &captured_part_of_prefix)) &&
+      !captured_part_of_prefix.empty()) {
+    // If this succeeded, then we must have had a transform rule and there must
+    // have been some part of the prefix that we captured.
+    // We make the transformation and check that the resultant number is viable.
+    // If so, replace the number and return.
+    possible_national_prefix_pattern.Replace(&number_string_copy,
+                                             transform_rule);
+    if (national_number_rule.FullMatch(number_string_copy)) {
+      number->assign(number_string_copy);
+      if (carrier_code) {
+        carrier_code->assign(carrier_code_temp);
+      }
+    }
+  } else if (possible_national_prefix_pattern.Consume(
+                 number_copy_without_transform.get(), &carrier_code_temp) ||
+             possible_national_prefix_pattern.Consume(
+                 number_copy_without_transform.get())) {
+    VLOG(4) << "Parsed the first digits as a national prefix.";
+    // If captured_part_of_prefix is empty, this implies nothing was captured by
+    // the capturing groups in possible_national_prefix; therefore, no
+    // transformation is necessary, and we just remove the national prefix.
+    const string number_copy_as_string =
+        number_copy_without_transform->ToString();
+    if (national_number_rule.FullMatch(number_copy_as_string)) {
+      number->assign(number_copy_as_string);
+      if (carrier_code) {
+        carrier_code->assign(carrier_code_temp);
+      }
+    }
+  } else {
+    VLOG(4) << "The first digits did not match the national prefix.";
+  }
+}
+
+// Strips any extension (as in, the part of the number dialled after the call is
+// connected, usually indicated with extn, ext, x or similar) from the end of
+// the number, and returns it. The number passed in should be non-normalized.
+bool PhoneNumberUtil::MaybeStripExtension(string* number, string* extension)
+    const {
+  DCHECK(number);
+  DCHECK(extension);
+  // There are three extension capturing groups in the regular expression.
+  string possible_extension_one;
+  string possible_extension_two;
+  string possible_extension_three;
+  string number_copy(*number);
+  const scoped_ptr<RegExpInput> number_copy_as_regexp_input(
+      RegExpInput::Create(number_copy));
+  if (extn_pattern->Consume(number_copy_as_regexp_input.get(),
+                            false,
+                            &possible_extension_one,
+                            &possible_extension_two,
+                            &possible_extension_three)) {
+    // Replace the extensions in the original string here.
+    extn_pattern->Replace(&number_copy, "");
+    VLOG(4) << "Found an extension. Possible extension one: "
+            << possible_extension_one
+            << ". Possible extension two: " << possible_extension_two
+            << ". Possible extension three: " << possible_extension_three
+            << ". Remaining number: " << number_copy;
+    // If we find a potential extension, and the number preceding this is a
+    // viable number, we assume it is an extension.
+    if ((!possible_extension_one.empty() || !possible_extension_two.empty() ||
+         !possible_extension_three.empty()) &&
+        IsViablePhoneNumber(number_copy)) {
+      number->assign(number_copy);
+      if (!possible_extension_one.empty()) {
+        extension->assign(possible_extension_one);
+      } else if (!possible_extension_two.empty()) {
+        extension->assign(possible_extension_two);
+      } else if (!possible_extension_three.empty()) {
+        extension->assign(possible_extension_three);
+      }
+      return true;
+    }
+  }
+  return false;
+}
+
+// Extracts country calling code from national_number, and returns it. It
+// assumes that the leading plus sign or IDD has already been removed. Returns 0
+// if national_number doesn't start with a valid country calling code, and
+// leaves national_number unmodified. Assumes the national_number is at least 3
+// characters long.
+int PhoneNumberUtil::ExtractCountryCode(string* national_number) const {
+  int potential_country_code;
+  for (size_t i = 1; i <= kMaxLengthCountryCode; ++i) {
+    safe_strto32(national_number->substr(0, i), &potential_country_code);
+    string region_code;
+    GetRegionCodeForCountryCode(potential_country_code, &region_code);
+    if (region_code != RegionCode::GetUnknown()) {
+      national_number->erase(0, i);
+      return potential_country_code;
+    }
+  }
+  return 0;
+}
+
+// Tries to extract a country calling code from a number. Country calling codes
+// are extracted in the following ways:
+//   - by stripping the international dialing prefix of the region the person
+//   is dialing from, if this is present in the number, and looking at the next
+//   digits
+//   - by stripping the '+' sign if present and then looking at the next digits
+//   - by comparing the start of the number and the country calling code of the
+//   default region. If the number is not considered possible for the numbering
+//   plan of the default region initially, but starts with the country calling
+//   code of this region, validation will be reattempted after stripping this
+//   country calling code. If this number is considered a possible number, then
+//   the first digits will be considered the country calling code and removed as
+//   such.
+//
+//   Returns NO_PARSING_ERROR if a country calling code was successfully
+//   extracted or none was present, or the appropriate error otherwise, such as
+//   if a + was present but it was not followed by a valid country calling code.
+//   If NO_PARSING_ERROR is returned, the national_number without the country
+//   calling code is populated, and the country_code passed in is set to the
+//   country calling code if found, otherwise to 0.
+PhoneNumberUtil::ErrorType PhoneNumberUtil::MaybeExtractCountryCode(
+    const PhoneMetadata* default_region_metadata,
+    bool keep_raw_input,
+    string* national_number,
+    PhoneNumber* phone_number) const {
+  DCHECK(national_number);
+  DCHECK(phone_number);
+  // Set the default prefix to be something that will never match if there is no
+  // default region.
+  string possible_country_idd_prefix = default_region_metadata
+      ?  default_region_metadata->international_prefix()
+      : "NonMatch";
+  PhoneNumber::CountryCodeSource country_code_source =
+      MaybeStripInternationalPrefixAndNormalize(possible_country_idd_prefix,
+                                                national_number);
+  if (keep_raw_input) {
+    phone_number->set_country_code_source(country_code_source);
+  }
+  if (country_code_source != PhoneNumber::FROM_DEFAULT_COUNTRY) {
+    if (national_number->length() < kMinLengthForNsn) {
+      VLOG(2) << "Phone number had an IDD, but after this was not "
+              << "long enough to be a viable phone number.";
+      return TOO_SHORT_AFTER_IDD;
+    }
+    int potential_country_code = ExtractCountryCode(national_number);
+    if (potential_country_code != 0) {
+      phone_number->set_country_code(potential_country_code);
+      return NO_PARSING_ERROR;
+    }
+    // If this fails, they must be using a strange country calling code that we
+    // don't recognize, or that doesn't exist.
+    return INVALID_COUNTRY_CODE_ERROR;
+  } else if (default_region_metadata) {
+    // Check to see if the number starts with the country calling code for the
+    // default region. If so, we remove the country calling code, and do some
+    // checks on the validity of the number before and after.
+    int default_country_code = default_region_metadata->country_code();
+    string default_country_code_string(SimpleItoa(default_country_code));
+    VLOG(4) << "Possible country calling code: " << default_country_code_string;
+    string potential_national_number;
+    if (TryStripPrefixString(*national_number,
+                             default_country_code_string,
+                             &potential_national_number)) {
+      const PhoneNumberDesc& general_num_desc =
+          default_region_metadata->general_desc();
+      const RegExp& valid_number_pattern =
+          regexp_cache->GetRegExp(general_num_desc.national_number_pattern());
+      MaybeStripNationalPrefixAndCarrierCode(*default_region_metadata,
+                                             &potential_national_number,
+                                             NULL);
+      VLOG(4) << "Number without country calling code prefix: "
+              << potential_national_number;
+      const RegExp& possible_number_pattern = regexp_cache->GetRegExp(
+          StrCat("(", general_num_desc.possible_number_pattern(), ")"));
+      // If the number was not valid before but is valid now, or if it was too
+      // long before, we consider the number with the country code stripped to
+      // be a better result and keep that instead.
+      if ((!valid_number_pattern.FullMatch(*national_number) &&
+           valid_number_pattern.FullMatch(potential_national_number)) ||
+           TestNumberLengthAgainstPattern(possible_number_pattern,
+                                          *national_number) == TOO_LONG) {
+        national_number->assign(potential_national_number);
+        if (keep_raw_input) {
+          phone_number->set_country_code_source(
+              PhoneNumber::FROM_NUMBER_WITHOUT_PLUS_SIGN);
+        }
+        phone_number->set_country_code(default_country_code);
+        return NO_PARSING_ERROR;
+      }
+    }
+  }
+  // No country calling code present. Set the country_code to 0.
+  phone_number->set_country_code(0);
+  return NO_PARSING_ERROR;
+}
+
+PhoneNumberUtil::MatchType PhoneNumberUtil::IsNumberMatch(
+    const PhoneNumber& first_number_in,
+    const PhoneNumber& second_number_in) const {
+  // Make copies of the phone number so that the numbers passed in are not
+  // edited.
+  PhoneNumber first_number(first_number_in);
+  PhoneNumber second_number(second_number_in);
+  // First clear raw_input and country_code_source and
+  // preferred_domestic_carrier_code fields and any empty-string extensions so
+  // that we can use the proto-buffer equality method.
+  first_number.clear_raw_input();
+  first_number.clear_country_code_source();
+  first_number.clear_preferred_domestic_carrier_code();
+  second_number.clear_raw_input();
+  second_number.clear_country_code_source();
+  second_number.clear_preferred_domestic_carrier_code();
+  if (first_number.extension().empty()) {
+    first_number.clear_extension();
+  }
+  if (second_number.extension().empty()) {
+    second_number.clear_extension();
+  }
+  // Early exit if both had extensions and these are different.
+  if (first_number.has_extension() && second_number.has_extension() &&
+      first_number.extension() != second_number.extension()) {
+    return NO_MATCH;
+  }
+  int first_number_country_code = first_number.country_code();
+  int second_number_country_code = second_number.country_code();
+  // Both had country calling code specified.
+  if (first_number_country_code != 0 && second_number_country_code != 0) {
+    if (ExactlySameAs(first_number, second_number)) {
+      return EXACT_MATCH;
+    } else if (first_number_country_code == second_number_country_code &&
+               IsNationalNumberSuffixOfTheOther(first_number, second_number)) {
+      // A SHORT_NSN_MATCH occurs if there is a difference because of the
+      // presence or absence of an 'Italian leading zero', the presence or
+      // absence of an extension, or one NSN being a shorter variant of the
+      // other.
+      return SHORT_NSN_MATCH;
+    }
+    // This is not a match.
+    return NO_MATCH;
+  }
+  // Checks cases where one or both country calling codes were not specified. To
+  // make equality checks easier, we first set the country_code fields to be
+  // equal.
+  first_number.set_country_code(second_number_country_code);
+  // If all else was the same, then this is an NSN_MATCH.
+  if (ExactlySameAs(first_number, second_number)) {
+    return NSN_MATCH;
+  }
+  if (IsNationalNumberSuffixOfTheOther(first_number, second_number)) {
+    return SHORT_NSN_MATCH;
+  }
+  return NO_MATCH;
+}
+
+PhoneNumberUtil::MatchType PhoneNumberUtil::IsNumberMatchWithTwoStrings(
+    const string& first_number,
+    const string& second_number) const {
+  PhoneNumber first_number_as_proto;
+  ErrorType error_type =
+      Parse(first_number, RegionCode::GetUnknown(), &first_number_as_proto);
+  if (error_type == NO_PARSING_ERROR) {
+    return IsNumberMatchWithOneString(first_number_as_proto, second_number);
+  }
+  if (error_type == INVALID_COUNTRY_CODE_ERROR) {
+    PhoneNumber second_number_as_proto;
+    ErrorType error_type = Parse(second_number, RegionCode::GetUnknown(),
+                                 &second_number_as_proto);
+    if (error_type == NO_PARSING_ERROR) {
+      return IsNumberMatchWithOneString(second_number_as_proto, first_number);
+    }
+    if (error_type == INVALID_COUNTRY_CODE_ERROR) {
+      error_type  = ParseHelper(first_number, RegionCode::GetUnknown(), false,
+                                false, &first_number_as_proto);
+      if (error_type == NO_PARSING_ERROR) {
+        error_type = ParseHelper(second_number, RegionCode::GetUnknown(), false,
+                                 false, &second_number_as_proto);
+        if (error_type == NO_PARSING_ERROR) {
+          return IsNumberMatch(first_number_as_proto, second_number_as_proto);
+        }
+      }
+    }
+  }
+  // One or more of the phone numbers we are trying to match is not a viable
+  // phone number.
+  return INVALID_NUMBER;
+}
+
+PhoneNumberUtil::MatchType PhoneNumberUtil::IsNumberMatchWithOneString(
+    const PhoneNumber& first_number,
+    const string& second_number) const {
+  // First see if the second number has an implicit country calling code, by
+  // attempting to parse it.
+  PhoneNumber second_number_as_proto;
+  ErrorType error_type =
+      Parse(second_number, RegionCode::GetUnknown(), &second_number_as_proto);
+  if (error_type == NO_PARSING_ERROR) {
+    return IsNumberMatch(first_number, second_number_as_proto);
+  }
+  if (error_type == INVALID_COUNTRY_CODE_ERROR) {
+    // The second number has no country calling code. EXACT_MATCH is no longer
+    // possible.  We parse it as if the region was the same as that for the
+    // first number, and if EXACT_MATCH is returned, we replace this with
+    // NSN_MATCH.
+    string first_number_region;
+    GetRegionCodeForCountryCode(first_number.country_code(),
+                                &first_number_region);
+    if (first_number_region != RegionCode::GetUnknown()) {
+      PhoneNumber second_number_with_first_number_region;
+      Parse(second_number, first_number_region,
+            &second_number_with_first_number_region);
+      MatchType match = IsNumberMatch(first_number,
+                                      second_number_with_first_number_region);
+      if (match == EXACT_MATCH) {
+        return NSN_MATCH;
+      }
+      return match;
+    } else {
+      // If the first number didn't have a valid country calling code, then we
+      // parse the second number without one as well.
+      error_type = ParseHelper(second_number, RegionCode::GetUnknown(), false,
+                               false, &second_number_as_proto);
+      if (error_type == NO_PARSING_ERROR) {
+        return IsNumberMatch(first_number, second_number_as_proto);
+      }
+    }
+  }
+  // One or more of the phone numbers we are trying to match is not a viable
+  // phone number.
+  return INVALID_NUMBER;
+}
+
+}  // namespace phonenumbers
+}  // namespace i18n