<?php
if (extension_loaded('mbstring')) {
    mb_internal_encoding('UTF-8');

    function utf8_strlen($string) {
        return mb_strlen($string);
    }

    function utf8_strpos($string, $needle, $offset = 0) {
        return mb_strpos($string, $needle, $offset);
    }

    function utf8_strrpos($string, $needle, $offset = 0) {
        return mb_strrpos($string, $needle, $offset);
    }

    function utf8_substr($string, $offset, $length = null) {
        if ($length === null) {
            return mb_substr($string, $offset, utf8_strlen($string));
        } else {
            return mb_substr($string, $offset, $length);
        }
    }

    function utf8_strtoupper($string) {
        return mb_strtoupper($string);
    }

    function utf8_strtolower($string) {
        return mb_strtolower($string);
    }

} elseif (function_exists('iconv')) {

    function utf8_strlen($string) {
        return iconv_strlen($string, 'UTF-8');
    }

    function utf8_strpos($string, $needle, $offset = 0) {
        return iconv_strpos($string, $needle, $offset, 'UTF-8');
    }

    function utf8_strrpos($string, $needle) {
        return iconv_strrpos($string, $needle, 'UTF-8');
    }

    function utf8_substr($string, $offset, $length = null) {
        if ($length === null) {
            return iconv_substr($string, $offset, utf8_strlen($string), 'UTF-8');
        } else {
            return iconv_substr($string, $offset, $length, 'UTF-8');
        }
    }

    function utf8_strtolower($string) {
        static $upper_to_lower;

        if ($upper_to_lower == null) {
            $upper_to_lower = array(
                0x0041 => 0x0061,
                0x03A6 => 0x03C6,
                0x0162 => 0x0163,
                0x00C5 => 0x00E5,
                0x0042 => 0x0062,
                0x0139 => 0x013A,
                0x00C1 => 0x00E1,
                0x0141 => 0x0142,
                0x038E => 0x03CD,
                0x0100 => 0x0101,
                0x0490 => 0x0491,
                0x0394 => 0x03B4,
                0x015A => 0x015B,
                0x0044 => 0x0064,
                0x0393 => 0x03B3,
                0x00D4 => 0x00F4,
                0x042A => 0x044A,
                0x0419 => 0x0439,
                0x0112 => 0x0113,
                0x041C => 0x043C,
                0x015E => 0x015F,
                0x0143 => 0x0144,
                0x00CE => 0x00EE,
                0x040E => 0x045E,
                0x042F => 0x044F,
                0x039A => 0x03BA,
                0x0154 => 0x0155,
                0x0049 => 0x0069,
                0x0053 => 0x0073,
                0x1E1E => 0x1E1F,
                0x0134 => 0x0135,
                0x0427 => 0x0447,
                0x03A0 => 0x03C0,
                0x0418 => 0x0438,
                0x00D3 => 0x00F3,
                0x0420 => 0x0440,
                0x0404 => 0x0454,
                0x0415 => 0x0435,
                0x0429 => 0x0449,
                0x014A => 0x014B,
                0x0411 => 0x0431,
                0x0409 => 0x0459,
                0x1E02 => 0x1E03,
                0x00D6 => 0x00F6,
                0x00D9 => 0x00F9,
                0x004E => 0x006E,
                0x0401 => 0x0451,
                0x03A4 => 0x03C4,
                0x0423 => 0x0443,
                0x015C => 0x015D,
                0x0403 => 0x0453,
                0x03A8 => 0x03C8,
                0x0158 => 0x0159,
                0x0047 => 0x0067,
                0x00C4 => 0x00E4,
                0x0386 => 0x03AC,
                0x0389 => 0x03AE,
                0x0166 => 0x0167,
                0x039E => 0x03BE,
                0x0164 => 0x0165,
                0x0116 => 0x0117,
                0x0108 => 0x0109,
                0x0056 => 0x0076,
                0x00DE => 0x00FE,
                0x0156 => 0x0157,
                0x00DA => 0x00FA,
                0x1E60 => 0x1E61,
                0x1E82 => 0x1E83,
                0x00C2 => 0x00E2,
                0x0118 => 0x0119,
                0x0145 => 0x0146,
                0x0050 => 0x0070,
                0x0150 => 0x0151,
                0x042E => 0x044E,
                0x0128 => 0x0129,
                0x03A7 => 0x03C7,
                0x013D => 0x013E,
                0x0422 => 0x0442,
                0x005A => 0x007A,
                0x0428 => 0x0448,
                0x03A1 => 0x03C1,
                0x1E80 => 0x1E81,
                0x016C => 0x016D,
                0x00D5 => 0x00F5,
                0x0055 => 0x0075,
                0x0176 => 0x0177,
                0x00DC => 0x00FC,
                0x1E56 => 0x1E57,
                0x03A3 => 0x03C3,
                0x041A => 0x043A,
                0x004D => 0x006D,
                0x016A => 0x016B,
                0x0170 => 0x0171,
                0x0424 => 0x0444,
                0x00CC => 0x00EC,
                0x0168 => 0x0169,
                0x039F => 0x03BF,
                0x004B => 0x006B,
                0x00D2 => 0x00F2,
                0x00C0 => 0x00E0,
                0x0414 => 0x0434,
                0x03A9 => 0x03C9,
                0x1E6A => 0x1E6B,
                0x00C3 => 0x00E3,
                0x042D => 0x044D,
                0x0416 => 0x0436,
                0x01A0 => 0x01A1,
                0x010C => 0x010D,
                0x011C => 0x011D,
                0x00D0 => 0x00F0,
                0x013B => 0x013C,
                0x040F => 0x045F,
                0x040A => 0x045A,
                0x00C8 => 0x00E8,
                0x03A5 => 0x03C5,
                0x0046 => 0x0066,
                0x00DD => 0x00FD,
                0x0043 => 0x0063,
                0x021A => 0x021B,
                0x00CA => 0x00EA,
                0x0399 => 0x03B9,
                0x0179 => 0x017A,
                0x00CF => 0x00EF,
                0x01AF => 0x01B0,
                0x0045 => 0x0065,
                0x039B => 0x03BB,
                0x0398 => 0x03B8,
                0x039C => 0x03BC,
                0x040C => 0x045C,
                0x041F => 0x043F,
                0x042C => 0x044C,
                0x00DE => 0x00FE,
                0x00D0 => 0x00F0,
                0x1EF2 => 0x1EF3,
                0x0048 => 0x0068,
                0x00CB => 0x00EB,
                0x0110 => 0x0111,
                0x0413 => 0x0433,
                0x012E => 0x012F,
                0x00C6 => 0x00E6,
                0x0058 => 0x0078,
                0x0160 => 0x0161,
                0x016E => 0x016F,
                0x0391 => 0x03B1,
                0x0407 => 0x0457,
                0x0172 => 0x0173,
                0x0178 => 0x00FF,
                0x004F => 0x006F,
                0x041B => 0x043B,
                0x0395 => 0x03B5,
                0x0425 => 0x0445,
                0x0120 => 0x0121,
                0x017D => 0x017E,
                0x017B => 0x017C,
                0x0396 => 0x03B6,
                0x0392 => 0x03B2,
                0x0388 => 0x03AD,
                0x1E84 => 0x1E85,
                0x0174 => 0x0175,
                0x0051 => 0x0071,
                0x0417 => 0x0437,
                0x1E0A => 0x1E0B,
                0x0147 => 0x0148,
                0x0104 => 0x0105,
                0x0408 => 0x0458,
                0x014C => 0x014D,
                0x00CD => 0x00ED,
                0x0059 => 0x0079,
                0x010A => 0x010B,
                0x038F => 0x03CE,
                0x0052 => 0x0072,
                0x0410 => 0x0430,
                0x0405 => 0x0455,
                0x0402 => 0x0452,
                0x0126 => 0x0127,
                0x0136 => 0x0137,
                0x012A => 0x012B,
                0x038A => 0x03AF,
                0x042B => 0x044B,
                0x004C => 0x006C,
                0x0397 => 0x03B7,
                0x0124 => 0x0125,
                0x0218 => 0x0219,
                0x00DB => 0x00FB,
                0x011E => 0x011F,
                0x041E => 0x043E,
                0x1E40 => 0x1E41,
                0x039D => 0x03BD,
                0x0106 => 0x0107,
                0x03AB => 0x03CB,
                0x0426 => 0x0446,
                0x00DE => 0x00FE,
                0x00C7 => 0x00E7,
                0x03AA => 0x03CA,
                0x0421 => 0x0441,
                0x0412 => 0x0432,
                0x010E => 0x010F,
                0x00D8 => 0x00F8,
                0x0057 => 0x0077,
                0x011A => 0x011B,
                0x0054 => 0x0074,
                0x004A => 0x006A,
                0x040B => 0x045B,
                0x0406 => 0x0456,
                0x0102 => 0x0103,
                0x039B => 0x03BB,
                0x00D1 => 0x00F1,
                0x041D => 0x043D,
                0x038C => 0x03CC,
                0x00C9 => 0x00E9,
                0x00D0 => 0x00F0,
                0x0407 => 0x0457,
                0x0122 => 0x0123
            );
        }

        $unicode = utf8_to_unicode($string);

        if (!$unicode) {
            return false;
        }

        for ($i = 0; $i < count($unicode); $i++) {
            if (isset($upper_to_lower[$unicode[$i]])) {
                $unicode[$i] = $upper_to_lower[$unicode[$i]];
            }
        }

        return unicode_to_utf8($unicode);
    }

    function utf8_strtoupper($string) {
        static $lower_to_upper;

        if ($lower_to_upper == null) {
            $lower_to_upper = array(
                0x0061 => 0x0041,
                0x03C6 => 0x03A6,
                0x0163 => 0x0162,
                0x00E5 => 0x00C5,
                0x0062 => 0x0042,
                0x013A => 0x0139,
                0x00E1 => 0x00C1,
                0x0142 => 0x0141,
                0x03CD => 0x038E,
                0x0101 => 0x0100,
                0x0491 => 0x0490,
                0x03B4 => 0x0394,
                0x015B => 0x015A,
                0x0064 => 0x0044,
                0x03B3 => 0x0393,
                0x00F4 => 0x00D4,
                0x044A => 0x042A,
                0x0439 => 0x0419,
                0x0113 => 0x0112,
                0x043C => 0x041C,
                0x015F => 0x015E,
                0x0144 => 0x0143,
                0x00EE => 0x00CE,
                0x045E => 0x040E,
                0x044F => 0x042F,
                0x03BA => 0x039A,
                0x0155 => 0x0154,
                0x0069 => 0x0049,
                0x0073 => 0x0053,
                0x1E1F => 0x1E1E,
                0x0135 => 0x0134,
                0x0447 => 0x0427,
                0x03C0 => 0x03A0,
                0x0438 => 0x0418,
                0x00F3 => 0x00D3,
                0x0440 => 0x0420,
                0x0454 => 0x0404,
                0x0435 => 0x0415,
                0x0449 => 0x0429,
                0x014B => 0x014A,
                0x0431 => 0x0411,
                0x0459 => 0x0409,
                0x1E03 => 0x1E02,
                0x00F6 => 0x00D6,
                0x00F9 => 0x00D9,
                0x006E => 0x004E,
                0x0451 => 0x0401,
                0x03C4 => 0x03A4,
                0x0443 => 0x0423,
                0x015D => 0x015C,
                0x0453 => 0x0403,
                0x03C8 => 0x03A8,
                0x0159 => 0x0158,
                0x0067 => 0x0047,
                0x00E4 => 0x00C4,
                0x03AC => 0x0386,
                0x03AE => 0x0389,
                0x0167 => 0x0166,
                0x03BE => 0x039E,
                0x0165 => 0x0164,
                0x0117 => 0x0116,
                0x0109 => 0x0108,
                0x0076 => 0x0056,
                0x00FE => 0x00DE,
                0x0157 => 0x0156,
                0x00FA => 0x00DA,
                0x1E61 => 0x1E60,
                0x1E83 => 0x1E82,
                0x00E2 => 0x00C2,
                0x0119 => 0x0118,
                0x0146 => 0x0145,
                0x0070 => 0x0050,
                0x0151 => 0x0150,
                0x044E => 0x042E,
                0x0129 => 0x0128,
                0x03C7 => 0x03A7,
                0x013E => 0x013D,
                0x0442 => 0x0422,
                0x007A => 0x005A,
                0x0448 => 0x0428,
                0x03C1 => 0x03A1,
                0x1E81 => 0x1E80,
                0x016D => 0x016C,
                0x00F5 => 0x00D5,
                0x0075 => 0x0055,
                0x0177 => 0x0176,
                0x00FC => 0x00DC,
                0x1E57 => 0x1E56,
                0x03C3 => 0x03A3,
                0x043A => 0x041A,
                0x006D => 0x004D,
                0x016B => 0x016A,
                0x0171 => 0x0170,
                0x0444 => 0x0424,
                0x00EC => 0x00CC,
                0x0169 => 0x0168,
                0x03BF => 0x039F,
                0x006B => 0x004B,
                0x00F2 => 0x00D2,
                0x00E0 => 0x00C0,
                0x0434 => 0x0414,
                0x03C9 => 0x03A9,
                0x1E6B => 0x1E6A,
                0x00E3 => 0x00C3,
                0x044D => 0x042D,
                0x0436 => 0x0416,
                0x01A1 => 0x01A0,
                0x010D => 0x010C,
                0x011D => 0x011C,
                0x00F0 => 0x00D0,
                0x013C => 0x013B,
                0x045F => 0x040F,
                0x045A => 0x040A,
                0x00E8 => 0x00C8,
                0x03C5 => 0x03A5,
                0x0066 => 0x0046,
                0x00FD => 0x00DD,
                0x0063 => 0x0043,
                0x021B => 0x021A,
                0x00EA => 0x00CA,
                0x03B9 => 0x0399,
                0x017A => 0x0179,
                0x00EF => 0x00CF,
                0x01B0 => 0x01AF,
                0x0065 => 0x0045,
                0x03BB => 0x039B,
                0x03B8 => 0x0398,
                0x03BC => 0x039C,
                0x045C => 0x040C,
                0x043F => 0x041F,
                0x044C => 0x042C,
                0x00FE => 0x00DE,
                0x00F0 => 0x00D0,
                0x1EF3 => 0x1EF2,
                0x0068 => 0x0048,
                0x00EB => 0x00CB,
                0x0111 => 0x0110,
                0x0433 => 0x0413,
                0x012F => 0x012E,
                0x00E6 => 0x00C6,
                0x0078 => 0x0058,
                0x0161 => 0x0160,
                0x016F => 0x016E,
                0x03B1 => 0x0391,
                0x0457 => 0x0407,
                0x0173 => 0x0172,
                0x00FF => 0x0178,
                0x006F => 0x004F,
                0x043B => 0x041B,
                0x03B5 => 0x0395,
                0x0445 => 0x0425,
                0x0121 => 0x0120,
                0x017E => 0x017D,
                0x017C => 0x017B,
                0x03B6 => 0x0396,
                0x03B2 => 0x0392,
                0x03AD => 0x0388,
                0x1E85 => 0x1E84,
                0x0175 => 0x0174,
                0x0071 => 0x0051,
                0x0437 => 0x0417,
                0x1E0B => 0x1E0A,
                0x0148 => 0x0147,
                0x0105 => 0x0104,
                0x0458 => 0x0408,
                0x014D => 0x014C,
                0x00ED => 0x00CD,
                0x0079 => 0x0059,
                0x010B => 0x010A,
                0x03CE => 0x038F,
                0x0072 => 0x0052,
                0x0430 => 0x0410,
                0x0455 => 0x0405,
                0x0452 => 0x0402,
                0x0127 => 0x0126,
                0x0137 => 0x0136,
                0x012B => 0x012A,
                0x03AF => 0x038A,
                0x044B => 0x042B,
                0x006C => 0x004C,
                0x03B7 => 0x0397,
                0x0125 => 0x0124,
                0x0219 => 0x0218,
                0x00FB => 0x00DB,
                0x011F => 0x011E,
                0x043E => 0x041E,
                0x1E41 => 0x1E40,
                0x03BD => 0x039D,
                0x0107 => 0x0106,
                0x03CB => 0x03AB,
                0x0446 => 0x0426,
                0x00FE => 0x00DE,
                0x00E7 => 0x00C7,
                0x03CA => 0x03AA,
                0x0441 => 0x0421,
                0x0432 => 0x0412,
                0x010F => 0x010E,
                0x00F8 => 0x00D8,
                0x0077 => 0x0057,
                0x011B => 0x011A,
                0x0074 => 0x0054,
                0x006A => 0x004A,
                0x045B => 0x040B,
                0x0456 => 0x0406,
                0x0103 => 0x0102,
                0x03BB => 0x039B,
                0x00F1 => 0x00D1,
                0x043D => 0x041D,
                0x03CC => 0x038C,
                0x00E9 => 0x00C9,
                0x00F0 => 0x00D0,
                0x0457 => 0x0407,
                0x0123 => 0x0122
            );
        }

        $unicode = utf8_to_unicode($string);

        if (!$unicode) {
            return false;
        }

        for ($i = 0; $i < count($unicode); $i++) {
            if (isset($lower_to_upper[$unicode[$i]])) {
                $unicode[$i] = $lower_to_upper[$unicode[$i]];
            }
        }

        return unicode_to_utf8($unicode);
    }

    function utf8_to_unicode($string) {
        $unicode = array();

        for ($i = 0; $i < strlen($string); $i++) {
            $chr = ord($string[$i]);

            if ($chr >= 0 && $chr <= 127) {
                $unicode[] = (ord($string[$i]) * pow(64, 0));
            }

            if ($chr >= 192 && $chr <= 223) {
                $unicode[] = ((ord($string[$i]) - 192) * pow(64, 1) + (ord($string[$i + 1]) - 128) * pow(64, 0));
            }

            if ($chr >= 224 && $chr <= 239) {
                $unicode[] = ((ord($string[$i]) - 224) * pow(64, 2) + (ord($string[$i + 1]) - 128) * pow(64, 1) + (ord($string[$i + 2]) - 128) * pow(64, 0));
            }

            if ($chr >= 240 && $chr <= 247) {
                $unicode[] = ((ord($string[$i]) - 240) * pow(64, 3) + (ord($string[$i + 1]) - 128) * pow(64, 2) + (ord($string[$i + 2]) - 128) * pow(64, 1) + (ord($string[$i + 3]) - 128) * pow(64, 0));
            }

            if ($chr >= 248 && $chr <= 251) {
                $unicode[] = ((ord($string[$i]) - 248) * pow(64, 4) + (ord($string[$i + 1]) - 128) * pow(64, 3) + (ord($string[$i + 2]) - 128) * pow(64, 2) + (ord($string[$i + 3]) - 128) * pow(64, 1) + (ord($string[$i + 4]) - 128) * pow(64, 0));
            }

            if ($chr == 252 || $chr == 253) {
                $unicode[] = ((ord($string[$i]) - 252) * pow(64, 5) + (ord($string[$i + 1]) - 128) * pow(64, 4) + (ord($string[$i + 2]) - 128) * pow(64, 3) + (ord($string[$i + 3]) - 128) * pow(64, 2) + (ord($string[$i + 4]) - 128) * pow(64, 1) + (ord($string[$i + 5]) - 128) * pow(64, 0));
            }
        }

        return $unicode;
    }

    function unicode_to_utf8($unicode) {
        $string = '';

        for ($i = 0; $i < count($unicode); $i++) {
            if ($unicode[$i] < 128) {
                $string .= chr($unicode[$i]);
            }

            if ($unicode[$i] >= 128 && $unicode[$i] <= 2047) {
                $string .= chr(($unicode[$i] / 64) + 192) . chr(($unicode[$i] % 64) + 128);
            }

            if ($unicode[$i] >= 2048 && $unicode[$i] <= 65535) {
                $string .= chr(($unicode[$i] / 4096) + 224) . chr(128 + (($unicode[$i] / 64) % 64)) . chr(($unicode[$i] % 64) + 128);
            }

            if ($unicode[$i] >= 65536 && $unicode[$i] <= 2097151) {
                $string .= chr(($unicode[$i] / 262144) + 240) . chr((($unicode[$i] / 4096) % 64) + 128) . chr((($unicode[$i] / 64) % 64) + 128) . chr(($unicode[$i] % 64) + 128);
            }

            if ($unicode[$i] >= 2097152 && $unicode[$i] <= 67108863) {
                $string .= chr(($unicode[$i] / 16777216) + 248) . chr((($unicode[$i] / 262144) % 64) + 128) . chr((($unicode[$i] / 4096) % 64) + 128) . chr((($unicode[$i] / 64) % 64) + 128) . chr(($unicode[$i] % 64) + 128);
            }

            if ($unicode[$i] >= 67108864 && $unicode[$i] <= 2147483647) {
                $string .= chr(($unicode[$i] / 1073741824) + 252) . chr((($unicode[$i] / 16777216) % 64) + 128) . chr((($unicode[$i] / 262144) % 64) + 128) . chr(128 + (($unicode[$i] / 4096) % 64)) . chr((($unicode[$i] / 64) % 64) + 128) . chr(($unicode[$i] % 64) + 128);
            }
        }

        return $string;
    }

}
