<?php
/*********************************************
IPP - 1.projekt
Iva Kavankova
 *********************************************/

// TODO: ignor entru mezi radky a instrukce malymi pismeny

error_reporting(-1); // vypis vsech chyb

function error($msg) {
    fprintf(STDERR, "CHYBA: $msg!\n");
}

class InstructionRegister {
    public static $options = array(
        "MOVE" => "var_symb",
        "CREATEFRAME" => "",
        "PUSHFRAME" => "",
        "POPHFRAME" => "",
        "DEFVAR" => "var",
        "CALL" => "label",
        "RETURN" => "",
        "PUSHS" => "symb",
        "POPS" => "var",
        "ADD" => "var_symb_symb",
        "SUB" => "var_symb_symb",
        "MUL" => "var_symb_symb",
        "IDIV" => "var_symb_symb",
        "LT" => "var_symb_symb",
        "GT" => "var_symb_symb",
        "EQ" => "var_symb_symb",
        "AND" => "var_symb1_symb2",
        "OR" => "var_symb_symb",
        "NOT" => "var_symb_symb",
        "INT2CHAR" => "var_symb",
        "STRI2INT" => "var_symb_symb",
        "READ" => "var_type",
        "WRITE" => "symb",
        "CONCAT" => "var_symb_symb",
        "STRLEN" => "var_symb",
        "GETCHAR" => "var_symb_symb",
        "SETCHAR" => "var_symb_symb",
        "TYPE" => "var_symb",
        "LABEL" => "label",
        "JUMP" => "label",
        "JUMPIFEQ" => "label_symb_symb",
        "JUMPIFNEQ" => "label_symb_symb",
        "DPRINT" => "symb",
        "BREAK" => "",
    );
}

// napoveda
function help() {
    echo "Tento skript parse.php nacte ze standardniho vstupu zdrojovy kod v jazyce IPPcode18, zkontroluje lexikalni a syntaktickou spravnost kodu.\nNakonec vypise na stdout vystup ve forme XML reprezentace programu.";
}

// nacteni argumentu
if ($argc == 2) {
    if ($argc > 1 && strcmp($argv[1], "--help") == 0) {
        help();
        exit(0);
    }
    else {
        error("chybne zadani argumentu");
        exit(10);
    }
}
else if ($argc > 2) {
    error("chybne zadani argumentu");
    exit(10);
}

// nacitani ze stdin
$inputStream = STDIN;
if ($inputStream === FALSE) {
    error("nelze nacist soubor");
    exit(1);
}

// kontrola
function checkSignature($opcode, $foundType, $index) {
    $instructionOptions = array(
        "MOVE" => "var_symb",
        "CREATEFRAME" => "",
        "PUSHFRAME" => "",
        "POPFRAME" => "",
        "DEFVAR" => "var",
        "CALL" => "label",
        "RETURN" => "",
        "PUSHS" => "symb",
        "POPS" => "var",
        "ADD" => "var_symb_symb",
        "SUB" => "var_symb_symb",
        "MUL" => "var_symb_symb",
        "IDIV" => "var_symb_symb",
        "LT" => "var_symb_symb",
        "GT" => "var_symb_symb",
        "EQ" => "var_symb_symb",
        "AND" => "var_symb1_symb2",
        "OR" => "var_symb_symb",
        "NOT" => "var_symb_symb",
        "INT2CHAR" => "var_symb",
        "STRI2INT" => "var_symb_symb",
        "READ" => "var_type",
        "WRITE" => "symb",
        "CONCAT" => "var_symb_symb",
        "STRLEN" => "var_symb",
        "GETCHAR" => "var_symb_symb",
        "SETCHAR" => "var_symb_symb",
        "TYPE" => "var_symb",
        "LABEL" => "label",
        "JUMP" => "label",
        "JUMPIFEQ" => "label_symb_symb",
        "JUMPIFNEQ" => "label_symb_symb",
        "DPRINT" => "symb",
        "BREAK" => "",
    );

    if(array_key_exists($opcode, $instructionOptions) == FALSE)
    {
        error("neznamy operacni kod instrukce: ($opcode)");
        return FALSE;
    }
    $instructionSignature = explode('_', $instructionOptions[$opcode]);
    if($index < count($instructionSignature)) {
        //$instructionOptions[$opcode];
        if ($instructionSignature[$index] == $foundType) {
            return TRUE;
        }
        elseif ($instructionSignature[$index] == 'symb'){
            if(in_array($foundType, ['var', 'int', 'string', 'bool'])) {
                return TRUE;
            }
            else {
                error("spatny typ opreandu");
                return FALSE;
            }
        }
        else {
            error("nenalezen operand");
            return FALSE;
        }
    }
    else {
        error("prebytecny operand");
        return FALSE;
    }
    error("vsechno spatne");
    return FALSE;
}

$text = stream_get_contents($inputStream); // retezec

function parseInput($input) {
    $lines = preg_split('/[\n\r]/', $input);
    $hasHeader = FALSE;
    $parsedLines = [];
    foreach ($lines as $lineNumber => $line) {
        $hashIndex = strpos($line, '#');
        if ($hashIndex !== FALSE) {
            $line = substr($line, 0, $hashIndex);
        }
        $line = trim($line);
        if ($line == '') continue;

        if (mb_strtoupper($line) == '.IPPCODE18' && !$hasHeader) {
            $hasHeader = TRUE;
            continue;
        }
        if (!$hasHeader) {
            error("nema povinnou hlavicku");
            return FALSE;
        }
        $parsedLines[] = $line;
    }
    return $parsedLines;
}

// parsovani operandu
function parseOperand($parentElement, $lineParts, $index) {
    $part = $lineParts[$index];
    $elementText = $elementType = '';

    if (strpos($part, '@') !== FALSE) {

        list($opType, $opContent) = explode('@', $part, 2);

        if ($opType == 'int') {
            $elementText = $opContent;
            $elementType = $opType;
        } else if ($opType == 'bool') {
            $elementText = $opContent;
            $elementType = $opType;
        } else if ($opType == 'string') {
            $elementText = $opContent;
            $elementType = $opType;
        } else if (in_array($opType, ['GF', 'LF', 'TF'])) {
            $elementText = $part;
            $elementType = 'var';
        } else {
            throw new Exception("problem $opType, $part", 1);
        }


    } else {
        if ($lineParts[0] == 'READ' && $index == 2) {
            $elementText = $part;
            $elementType = 'type';
        } else {
            $elementText = $part;
            $elementType = 'label';
        }
    }

    if (checkSignature($lineParts[0], $elementType, $index - 1) == FALSE)
    {
        error("nastal mensi problem: $lineParts, $index, $elementType");
        return NULL;
    }

    $argElement = $parentElement->addChild('arg' . $index, $elementText);
    $argElement->addAttribute('type', $elementType);
    return $argElement;
}

$lines = parseInput($text);

// zacatek generovani XML dokumentu
$programElement = new SimpleXMLElement('<?xml version="1.0" encoding="UTF-8"?><program />');
$programElement->addAttribute('language', 'IPPcode18');

function generateInstructions($lines, $programElement) {

    foreach ($lines as $instructionOrder => $line) {
        $parts = preg_split("/\s+/", $line);

        $instructionElement = $programElement->addChild('instruction');

        $opcode = $parts[0];


        $instructionElement->addAttribute('opcode', $opcode);

        $opcode = mb_strtoupper($opcode);
        if (!array_key_exists($opcode, InstructionRegister::$options)) {
            error("nenalezena instrukce");
            return FALSE;
        }

        $operandsCount = count($parts) - 1;

        if ($operandsCount > 0) {
            if(parseOperand($instructionElement, $parts, 1) == NULL) {
                error("nespravny operand 1: $line");
                return FALSE;
            }
        }
        if ($operandsCount > 1) {
            if(parseOperand($instructionElement, $parts, 2) == NULL) {
                error("nespravny operand 2: $line");
                return FALSE;
            }
        }
        if ($operandsCount > 2) {
            if(parseOperand($instructionElement, $parts, 3) == NULL) {
                error("nespravny operand 3: $line");
                return FALSE;
            }
        }
        if ($operandsCount > 3) {
            error("prilis mnoho operandu");
            return FALSE;
        }
    }
    return TRUE;
}

// chybovy navratovy kod specificky pro analyzator
if (!generateInstructions($lines,$programElement)) {
    exit(21);
}

// vygenerovani zbytku XML
echo $programElement->asXML();

exit(0); // bez problemu