text: // Copyright 2017 The Abseil Authors.
  //
  // 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.
  
  #include "s2/third_party/absl/strings/ascii.h"
  
  namespace absl {
  namespace ascii_internal {
  
  // # Table generated by this Python code (bit 0x02 is currently unused):
  // TODO(user) Move Python code for generation of table to BUILD and link here.
  
  // NOTE: The kAsciiPropertyBits table used within this code was generated by
  // Python code of the following form. (Bit 0x02 is currently unused and
  // available.)
  //
  // def Hex2(n):
  //   return '0x' + hex(n/16)[2:] + hex(n%16)[2:]
  // def IsPunct(ch):
  //   return (ord(ch) >= 32 and ord(ch) < 127 and
  //           not ch.isspace() and not ch.isalnum())
  // def IsBlank(ch):
  //   return ch in ' \t'
  // def IsCntrl(ch):
  //   return ord(ch) < 32 or ord(ch) == 127
  // def IsXDigit(ch):
  //   return ch.isdigit() or ch.lower() in 'abcdef'
  // for i in range(128):
  //   ch = chr(i)
  //   mask = ((ch.isalpha() and 0x01 or 0) |
  //           (ch.isalnum() and 0x04 or 0) |
  //           (ch.isspace() and 0x08 or 0) |
  //           (IsPunct(ch) and 0x10 or 0) |
  //           (IsBlank(ch) and 0x20 or 0) |
  //           (IsCntrl(ch) and 0x40 or 0) |
  //           (IsXDigit(ch) and 0x80 or 0))
  //   print Hex2(mask) + ',',
  //   if i % 16 == 7:
  //     print ' //', Hex2(i & 0x78)
  //   elif i % 16 == 15:
  //     print
  
  // clang-format off
  // Array of bitfields holding character information. Each bit value corresponds
  // to a particular character feature. For readability, and because the value
  // of these bits is tightly coupled to this implementation, the individual bits
  // are not named. Note that bitfields for all characters above ASCII 127 are
  // zero-initialized.
  const unsigned char kPropertyBits[256] = {
      0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40,  // 0x00
      0x40, 0x68, 0x48, 0x48, 0x48, 0x48, 0x40, 0x40,
      0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40,  // 0x10
      0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40,
      0x28, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10,  // 0x20
      0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10,
      0x84, 0x84, 0x84, 0x84, 0x84, 0x84, 0x84, 0x84,  // 0x30
      0x84, 0x84, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10,
      0x10, 0x85, 0x85, 0x85, 0x85, 0x85, 0x85, 0x05,  // 0x40
      0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05,
      0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05,  // 0x50
      0x05, 0x05, 0x05, 0x10, 0x10, 0x10, 0x10, 0x10,
      0x10, 0x85, 0x85, 0x85, 0x85, 0x85, 0x85, 0x05,  // 0x60
      0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05,
      0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05,  // 0x70
      0x05, 0x05, 0x05, 0x10, 0x10, 0x10, 0x10, 0x40,
  };
  
  // Array of characters for the ascii_tolower() function. For values 'A'
  // through 'Z', return the lower-case character; otherwise, return the
  // identity of the passed character.
  const char kToLower[256] = {
    '\x00', '\x01', '\x02', '\x03', '\x04', '\x05', '\x06', '\x07',
    '\x08', '\x09', '\x0a', '\x0b', '\x0c', '\x0d', '\x0e', '\x0f',
    '\x10', '\x11', '\x12', '\x13', '\x14', '\x15', '\x16', '\x17',
    '\x18', '\x19', '\x1a', '\x1b', '\x1c', '\x1d', '\x1e', '\x1f',
    '\x20', '\x21', '\x22', '\x23', '\x24', '\x25', '\x26', '\x27',
    '\x28', '\x29', '\x2a', '\x2b', '\x2c', '\x2d', '\x2e', '\x2f',
    '\x30', '\x31', '\x32', '\x33', '\x34', '\x35', '\x36', '\x37',
    '\x38', '\x39', '\x3a', '\x3b', '\x3c', '\x3d', '\x3e', '\x3f',
    '\x40',    'a',    'b',    'c',    'd',    'e',    'f',    'g',
       'h',    'i',    'j',    'k',    'l',    'm',    'n',    'o',
       'p',    'q',    'r',    's',    't',    'u',    'v',    'w',
       'x',    'y',    'z', '\x5b', '\x5c', '\x5d', '\x5e', '\x5f',
    '\x60', '\x61', '\x62', '\x63', '\x64', '\x65', '\x66', '\x67',
    '\x68', '\x69', '\x6a', '\x6b', '\x6c', '\x6d', '\x6e', '\x6f',
    '\x70', '\x71', '\x72', '\x73', '\x74', '\x75', '\x76', '\x77',
    '\x78', '\x79', '\x7a', '\x7b', '\x7c', '\x7d', '\x7e', '\x7f',
    '\x80', '\x81', '\x82', '\x83', '\x84', '\x85', '\x86', '\x87',
    '\x88', '\x89', '\x8a', '\x8b', '\x8c', '\x8d', '\x8e', '\x8f',
    '\x90', '\x91', '\x92', '\x93', '\x94', '\x95', '\x96', '\x97',
    '\x98', '\x99', '\x9a', '\x9b', '\x9c', '\x9d', '\x9e', '\x9f',
    '\xa0', '\xa1', '\xa2', '\xa3', '\xa4', '\xa5', '\xa6', '\xa7',
    '\xa8', '\xa9', '\xaa', '\xab', '\xac', '\xad', '\xae', '\xaf',
    '\xb0', '\xb1', '\xb2', '\xb3', '\xb4', '\xb5', '\xb6', '\xb7',
    '\xb8', '\xb9', '\xba', '\xbb', '\xbc', '\xbd', '\xbe', '\xbf',
    '\xc0', '\xc1', '\xc2', '\xc3', '\xc4', '\xc5', '\xc6', '\xc7',
    '\xc8', '\xc9', '\xca', '\xcb', '\xcc', '\xcd', '\xce', '\xcf',
    '\xd0', '\xd1', '\xd2', '\xd3', '\xd4', '\xd5', '\xd6', '\xd7',
    '\xd8', '\xd9', '\xda', '\xdb', '\xdc', '\xdd', '\xde', '\xdf',
    '\xe0', '\xe1', '\xe2', '\xe3', '\xe4', '\xe5', '\xe6', '\xe7',
    '\xe8', '\xe9', '\xea', '\xeb', '\xec', '\xed', '\xee', '\xef',
    '\xf0', '\xf1', '\xf2', '\xf3', '\xf4', '\xf5', '\xf6', '\xf7',
    '\xf8', '\xf9', '\xfa', '\xfb', '\xfc', '\xfd', '\xfe', '\xff',
  };
  
  // Array of characters for the ascii_toupper() function. For values 'a'
  // through 'z', return the upper-case character; otherwise, return the
  // identity of the passed character.
  const char kToUpper[256] = {
    '\x00', '\x01', '\x02', '\x03', '\x04', '\x05', '\x06', '\x07',
    '\x08', '\x09', '\x0a', '\x0b', '\x0c', '\x0d', '\x0e', '\x0f',
    '\x10', '\x11', '\x12', '\x13', '\x14', '\x15', '\x16', '\x17',
    '\x18', '\x19', '\x1a', '\x1b', '\x1c', '\x1d', '\x1e', '\x1f',
    '\x20', '\x21', '\x22', '\x23', '\x24', '\x25', '\x26', '\x27',
    '\x28', '\x29', '\x2a', '\x2b', '\x2c', '\x2d', '\x2e', '\x2f',
    '\x30', '\x31', '\x32', '\x33', '\x34', '\x35', '\x36', '\x37',
    '\x38', '\x39', '\x3a', '\x3b', '\x3c', '\x3d', '\x3e', '\x3f',
    '\x40', '\x41', '\x42', '\x43', '\x44', '\x45', '\x46', '\x47',
    '\x48', '\x49', '\x4a', '\x4b', '\x4c', '\x4d', '\x4e', '\x4f',
    '\x50', '\x51', '\x52', '\x53', '\x54', '\x55', '\x56', '\x57',
    '\x58', '\x59', '\x5a', '\x5b', '\x5c', '\x5d', '\x5e', '\x5f',
    '\x60',    'A',    'B',    'C',    'D',    'E',    'F',    'G',
       'H',    'I',    'J',    'K',    'L',    'M',    'N',    'O',
       'P',    'Q',    'R',    'S',    'T',    'U',    'V',    'W',
       'X',    'Y',    'Z', '\x7b', '\x7c', '\x7d', '\x7e', '\x7f',
    '\x80', '\x81', '\x82', '\x83', '\x84', '\x85', '\x86', '\x87',
    '\x88', '\x89', '\x8a', '\x8b', '\x8c', '\x8d', '\x8e', '\x8f',
    '\x90', '\x91', '\x92', '\x93', '\x94', '\x95', '\x96', '\x97',
    '\x98', '\x99', '\x9a', '\x9b', '\x9c', '\x9d', '\x9e', '\x9f',
    '\xa0', '\xa1', '\xa2', '\xa3', '\xa4', '\xa5', '\xa6', '\xa7',
    '\xa8', '\xa9', '\xaa', '\xab', '\xac', '\xad', '\xae', '\xaf',
    '\xb0', '\xb1', '\xb2', '\xb3', '\xb4', '\xb5', '\xb6', '\xb7',
    '\xb8', '\xb9', '\xba', '\xbb', '\xbc', '\xbd', '\xbe', '\xbf',
    '\xc0', '\xc1', '\xc2', '\xc3', '\xc4', '\xc5', '\xc6', '\xc7',
    '\xc8', '\xc9', '\xca', '\xcb', '\xcc', '\xcd', '\xce', '\xcf',
    '\xd0', '\xd1', '\xd2', '\xd3', '\xd4', '\xd5', '\xd6', '\xd7',
    '\xd8', '\xd9', '\xda', '\xdb', '\xdc', '\xdd', '\xde', '\xdf',
    '\xe0', '\xe1', '\xe2', '\xe3', '\xe4', '\xe5', '\xe6', '\xe7',
    '\xe8', '\xe9', '\xea', '\xeb', '\xec', '\xed', '\xee', '\xef',
    '\xf0', '\xf1', '\xf2', '\xf3', '\xf4', '\xf5', '\xf6', '\xf7',
    '\xf8', '\xf9', '\xfa', '\xfb', '\xfc', '\xfd', '\xfe', '\xff',
  };
  // clang-format on
  
  }  // namespace ascii_internal
  
  void AsciiStrToLower(string* s) {
    for (auto& ch : *s) {
      ch = absl::ascii_tolower(ch);
    }
  }
  
  void AsciiStrToUpper(string* s) {
    for (auto& ch : *s) {
      ch = absl::ascii_toupper(ch);
    }
  }
  
  void RemoveExtraAsciiWhitespace(string* str) {
    auto stripped = StripAsciiWhitespace(*str);
  
    if (stripped.empty()) {
      str->clear();
      return;
    }
  
    auto input_it = stripped.begin();
    auto input_end = stripped.end();
    auto output_it = &(*str)[0];
    bool is_ws = false;
  
    for (; input_it < input_end; ++input_it) {
      if (is_ws) {
        // Consecutive whitespace?  Keep only the last.
        is_ws = absl::ascii_isspace(*input_it);
        if (is_ws) --output_it;
      } else {
        is_ws = absl::ascii_isspace(*input_it);
      }
  
      *output_it = *input_it;
      ++output_it;
    }
  
    str->erase(output_it - &(*str)[0]);
  }
  
  }  // namespace absl
  