class Pangram
{
    private $inputString;
    private $it = 0;
    private $lettersCount;
    private $letterStrings;

    public function __construct($inputSentence)
    {
        $this->inputString = $inputSentence;
    }

    // determines if a function is a paragram
    // if the function is a paragram it returns -1
    // if its not a paragram it returns the character
    // which kept it from being a paragram.
    private function isPangram($str)
    {
        $alphabet = Array("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");

        foreach($alphabet as $val){
            if(stripos($str,$val) === false){
                return $val;
            }
        }
        return -1;
    }
    // returns the count of occurrences of each letter in "string"
    // into an array $array['a'] == occurrences of 'a'
    public function getLettersCount($string)
    {
        // reset all our vaules (we want a fresh count)
        $myLetterCount = array("a" => 0,"b" => 0,"c" => 0,"d" => 0,"e" => 0,
                                "f" => 0,"g" => 0,"h" => 0,"i" => 0,"j" => 0,
                                "k" => 0,"l" => 0,"m" => 0,"n" => 0,"o" => 0,
                                "p" => 0,"q" => 0,"r" => 0,"s" => 0,"t" => 0,
                                "u" => 0,"v" => 0,"w" => 0,"x" => 0,"y" => 0,
                                "z" => 0);

        $string = str_split(strtolower($string));
        foreach($string as $val) {
            if(ctype_alpha($val))
                $myLetterCount[$val]++;
        }

        return $myLetterCount;
    }
    // returns true when our "string" letter count matches the real letter
    // count of $this->lettersCount
    //
    // for example, if there are 5 'z's in the testString, then there needs to be 5 'z's
    // in the real string.
    private function checkLetterCount($string) {
        $returnVale = -1;
        $myLetterCount = array("a" => 0,"b" => 0,"c" => 0,"d" => 0,"e" => 0,
                                "f" => 0,"g" => 0,"h" => 0,"i" => 0,"j" => 0,
                                "k" => 0,"l" => 0,"m" => 0,"n" => 0,"o" => 0,
                                "p" => 0,"q" => 0,"r" => 0,"s" => 0,"t" => 0,
                                "u" => 0,"v" => 0,"w" => 0,"x" => 0,"y" => 0,
                                "z" => 0);
        $string = str_split(strtolower($string));

        // go over the inputed string and count each character
        // update each characters count in $myLetterCount[CHARACTER]
        // DONT count spaces or other things like ' and ;
        foreach($string as $val) {
            if(ctype_alpha($val))
                $myLetterCount[$val]++;
        }
        // for every value in $myLetterCount
        foreach($myLetterCount as $key => $value) {
            // if we find a character that doesnt have a match, then
            // thats a no no.. return -2
            if($myLetterCount[$key] != $this->lettersCount[$key])
                $returnVale = -2;
        }
        // if we didnt find a character that didnt have a match
        // then we are good to go!
        return $returnVale;
    }

    // append the literal values of an integer in a string
    // counts each letter in $this->lettersCount
    // if there are 6 a values.. it will append "six 'a's"
    private function appendValues($string) {
        foreach($this->lettersCount as $key => $value) {
            if($key == "z") {
                $this->letterStrings[$key] = "and " . $this->numtostr($value) . "'$key'";
                if($value > 1) $this->letterStrings[$key] .= 's';
                $this->letterStrings[$key] .=  " ";
            } else {
                $this->letterStrings[$key] =  $this->numtostr($value) . "'$key'";
                if($value > 1) $this->letterStrings[$key] .=  's';
                $this->letterStrings[$key] .=  ", ";
            }
            $string .= $this->letterStrings[$key];
        }
        return $string;
    }

    public function selfEnumerate() {
        // testString = "The solution to the CATS problem contains precisely"
        $testString = $this->inputString;

        // get a count for each letter.. in our case a = 2, b = 0, ..... t = 2
        $this->lettersCount = $this->getLettersCount(strtolower($testString));

        // clearly we dont have a panagram yet ... so loop through until we do!
        $testString = $this->appendValues($testString);

        //echo $testString . "\n";
        $checkPangram = $this->isPangram($testString);

        $checkLetterCount = $this->checkLetterCount($testString);

        //echo $checkLetterCount;
        //echo $checkPangram;

        while(1)
        {
            if($checkPangram != -1 && $checkLetterCount != -1)
                break;


            //print_r($this->lettersCount);
            $testString = $this->inputString;
            $testString = $this->appendValues($testString);

            $checkPangram = $this->isPangram($testString);
            $checkLetterCount = $this->checkLetterCount($testString);

            $this->lettersCount = $this->getLettersCount(strtolower($testString));
            //echo $testString . "\n";
            $this->it++;
            //if ($this->it % 1000 == 0)
            //echo $this->it . " \n\n";
        }


    }
    public function getIterations() {
        return $this->it;
    }

    function numtostr($num){
        if($num == 0)
            return 'zero ';
        else {
            $big = array(    '',
                            'thousand',
                            'million',
                            'billion',
                            'trillion',
                            'quadrillion',
                            'quintillion',
                            'sextillion',
                            'septillion');
            $small = array( '',
                            'one',
                            'two',
                            'three',
                            'four',
                            'five',
                            'six',
                            'seven',
                            'eight',
                            'nine',
                            'ten',
                            'eleven',
                            'twelve',
                            'thirteen',
                            'fourteen',
                            'fifteen',
                            'sixteen',
                            'seventeen',
                            'eighteen',
                            'nineteen');
            $other = array(    '',
                            '',
                            'twenty',
                            'thirty',
                            'fourty',
                            'fifty',
                            'sixty',
                            'seventy',
                            'eighty',
                            'ninety');
            $hun = 'hundred';
            $end = array();
            $num = strrev($num);
            $final = array();
            for($i=0; $i<strlen($num); $i+=3){
                $end[$i] = strrev(substr($num, $i, 3));
            }
            $end = array_reverse($end);
            for($i=0; $i<sizeof($end); $i++){
                $len = strlen($end[$i]);
                $temp = $end[$i];
                if($len == 3){
                    $final[] = $temp{0} != '0' ? $small[$end[$i]{0}] . ' ' . $hun : $small[$end[$i]{0}];
                    $end[$i] = substr($end[$i], 1, 2);
                }
                if($len > 1){
                    $final[] = array_key_exists($end[$i], $small) ? $small[$end[$i]] : $other[$end[$i]{0}] . ' ' . $small[$end[$i]{1}];
                }else{
                    $final[] = $small[$end[$i]{0}];
                }
                $final[] = $temp != '000' ? $big[sizeof($end) - $i - 1] : '';
            }
            return str_replace(array('  ', '  ', '  ', '  ', '  ', '  ', '  '), ' ', implode(' ',$final));
        }
    }
}