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<?php
/**
* @author Niels A.D.
* @author Todd Burry <todd@vanillaforums.com>
* @copyright 2010 Niels A.D., 2014 Todd Burry
* @license http://opensource.org/licenses/LGPL-2.1 LGPL-2.1
* @package pQuery
*/
namespace pagelayerQuery;
/**
* Converts a document into tokens
*
* Can convert any string into tokens. The base class only supports
* identifier/whitespace tokens. For more tokens, the class can be
* easily extended.
*
* Use like:
* <code>
* <?php
* $a = new TokenizerBase('hello word');
* while ($a->next() !== $a::TOK_NULL) {
* echo $a->token, ': ',$a->getTokenString(), "<br>\n";
* }
* ?>
* </code>
*
* @internal The tokenizer works with a character map that connects a certain
* character to a certain function/token. This class is build with speed in mind.
*/
class TokenizerBase {
/**
* NULL Token, used at end of document (parsing should stop after this token)
*/
const TOK_NULL = 0;
/**
* Unknown token, used at unidentified character
*/
const TOK_UNKNOWN = 1;
/**
* Whitespace token, used with whitespace
*/
const TOK_WHITESPACE = 2;
/**
* Identifier token, used with identifiers
*/
const TOK_IDENTIFIER = 3;
/**
* The document that is being tokenized
* @var string
* @internal Public for faster access!
* @see setDoc()
* @see getDoc()
* @access private
*/
var $doc = '';
/**
* The size of the document (length of string)
* @var int
* @internal Public for faster access!
* @see $doc
* @access private
*/
var $size = 0;
/**
* Current (character) position in the document
* @var int
* @internal Public for faster access!
* @see setPos()
* @see getPos()
* @access private
*/
var $pos = 0;
/**
* Current (Line/Column) position in document
* @var array (Current_Line, Line_Starting_Pos)
* @internal Public for faster access!
* @see getLinePos()
* @access private
*/
var $line_pos = array(0, 0);
/**
* Current token
* @var int
* @internal Public for faster access!
* @see getToken()
* @access private
*/
var $token = self::TOK_NULL;
/**
* Start position of token. If NULL, then current position is used.
* @var int
* @internal Public for faster access!
* @see getTokenString()
* @access private
*/
var $token_start = null;
/**
* List with all the character that can be considered as whitespace
* @var array|string
* @internal Variable is public + associated array for faster access!
* @internal array(' ' => true) will recognize space (' ') as whitespace
* @internal String will be converted to array in constructor
* @internal Result token will be {@link self::TOK_WHITESPACE};
* @see setWhitespace()
* @see getWhitespace()
* @access private
*/
var $whitespace = " \t\n\r\0\x0B";
/**
* List with all the character that can be considered as identifier
* @var array|string
* @internal Variable is public + associated array for faster access!
* @internal array('a' => true) will recognize 'a' as identifier
* @internal String will be converted to array in constructor
* @internal Result token will be {@link self::TOK_IDENTIFIER};
* @see setIdentifiers()
* @see getIdentifiers()
* @access private
*/
var $identifiers = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890_';
/**
* All characters that should be mapped to a token/function that cannot be considered as whitespace or identifier
* @var array
* @internal Variable is public + associated array for faster access!
* @internal array('a' => 'parse_a') will call $this->parse_a() if it matches the character 'a'
* @internal array('a' => self::TOK_A) will set token to TOK_A if it matches the character 'a'
* @see mapChar()
* @see unmapChar()
* @access private
*/
var $custom_char_map = array();
/**
* Automatically built character map. Built using {@link $identifiers}, {@link $whitespace} and {@link $custom_char_map}
* @var array
* @internal Public for faster access!
* @access private
*/
var $char_map = array();
/**
* All errors found while parsing the document
* @var array
* @see addError()
*/
var $errors = array();
/**
* Class constructor
* @param string $doc Document to be tokenized
* @param int $pos Position to start parsing
* @see setDoc()
* @see setPos()
*/
function __construct($doc = '', $pos = 0) {
$this->setWhitespace($this->whitespace);
$this->setIdentifiers($this->identifiers);
$this->setDoc($doc, $pos);
}
#php4 PHP4 class constructor compatibility
#function TokenizerBase($doc = '', $pos = 0) {return $this->__construct($doc, $pos);}
#php4e
/**
* Sets target document
* @param string $doc Document to be tokenized
* @param int $pos Position to start parsing
* @see getDoc()
* @see setPos()
*/
function setDoc($doc, $pos = 0) {
$this->doc = $doc;
$this->size = strlen($doc);
$this->setPos($pos);
}
/**
* Returns target document
* @return string
* @see setDoc()
*/
function getDoc() {
return $this->doc;
}
/**
* Sets position in document
* @param int $pos
* @see getPos()
*/
function setPos($pos = 0) {
$this->pos = $pos - 1;
$this->line_pos = array(0, 0);
$this->next();
}
/**
* Returns current position in document (Index)
* @return int
* @see setPos()
*/
function getPos() {
return $this->pos;
}
/**
* Returns current position in document (Line/Char)
* @return array array(Line, Column)
*/
function getLinePos() {
return array($this->line_pos[0], $this->pos - $this->line_pos[1]);
}
/**
* Returns current token
* @return int
* @see $token
*/
function getToken() {
return $this->token;
}
/**
* Returns current token as string
* @param int $start_offset Offset from token start
* @param int $end_offset Offset from token end
* @return string
*/
function getTokenString($start_offset = 0, $end_offset = 0) {
$token_start = ((is_int($this->token_start)) ? $this->token_start : $this->pos) + $start_offset;
$len = $this->pos - $token_start + 1 + $end_offset;
return (($len > 0) ? substr($this->doc, $token_start, $len) : '');
}
/**
* Sets characters to be recognized as whitespace
*
* Used like: setWhitespace('ab') or setWhitespace(array('a' => true, 'b', 'c'));
* @param string|array $ws
* @see getWhitespace();
*/
function setWhitespace($ws) {
if (is_array($ws)) {
$this->whitespace = array_fill_keys(array_values($ws), true);
$this->buildCharMap();
} else {
$this->setWhiteSpace(str_split($ws));
}
}
/**
* Returns whitespace characters as string/array
* @param bool $as_string Should the result be a string or an array?
* @return string|array
* @see setWhitespace()
*/
function getWhitespace($as_string = true) {
$ws = array_keys($this->whitespace);
return (($as_string) ? implode('', $ws) : $ws);
}
/**
* Sets characters to be recognized as identifier
*
* Used like: setIdentifiers('ab') or setIdentifiers(array('a' => true, 'b', 'c'));
* @param string|array $ident
* @see getIdentifiers();
*/
function setIdentifiers($ident) {
if (is_array($ident)) {
$this->identifiers = array_fill_keys(array_values($ident), true);
$this->buildCharMap();
} else {
$this->setIdentifiers(str_split($ident));
}
}
/**
* Returns identifier characters as string/array
* @param bool $as_string Should the result be a string or an array?
* @return string|array
* @see setIdentifiers()
*/
function getIdentifiers($as_string = true) {
$ident = array_keys($this->identifiers);
return (($as_string) ? implode('', $ident) : $ident);
}
/**
* Maps a custom character to a token/function
*
* Used like: mapChar('a', self::{@link TOK_IDENTIFIER}) or mapChar('a', 'parse_identifier');
* @param string $char Character that should be mapped. If set, it will be overridden
* @param int|string $map If function name, then $this->function will be called, otherwise token is set to $map
* @see unmapChar()
*/
function mapChar($char, $map) {
$this->custom_char_map[$char] = $map;
$this->buildCharMap();
}
/**
* Removes a char mapped with {@link mapChar()}
* @param string $char Character that should be unmapped
* @see mapChar()
*/
function unmapChar($char) {
unset($this->custom_char_map[$char]);
$this->buildCharMap();
}
/**
* Builds the {@link $map_char} array
* @internal Builds single array that maps all characters. Gets called if {@link $whitespace}, {@link $identifiers} or {@link $custom_char_map} get modified
*/
protected function buildCharMap() {
$this->char_map = $this->custom_char_map;
if (is_array($this->whitespace)) {
foreach($this->whitespace as $w => $v) {
$this->char_map[$w] = 'parse_whitespace';
}
}
if (is_array($this->identifiers)) {
foreach($this->identifiers as $i => $v) {
$this->char_map[$i] = 'parse_identifier';
}
}
}
/**
* Add error to the array and appends current position
* @param string $error
*/
function addError($error) {
$this->errors[] = htmlentities($error.' at '.($this->line_pos[0] + 1).', '.($this->pos - $this->line_pos[1] + 1).'!');
}
/**
* Parse line breaks and increase line number
* @internal Gets called to process line breaks
*/
protected function parse_linebreak() {
if($this->doc[$this->pos] === "\r") {
++$this->line_pos[0];
if ((($this->pos + 1) < $this->size) && ($this->doc[$this->pos + 1] === "\n")) {
++$this->pos;
}
$this->line_pos[1] = $this->pos;
} elseif($this->doc[$this->pos] === "\n") {
++$this->line_pos[0];
$this->line_pos[1] = $this->pos;
}
}
/**
* Parse whitespace
* @return int Token
* @internal Gets called with {@link $whitespace} characters
*/
protected function parse_whitespace() {
$this->token_start = $this->pos;
while(++$this->pos < $this->size) {
if (!isset($this->whitespace[$this->doc[$this->pos]])) {
break;
} else {
$this->parse_linebreak();
}
}
--$this->pos;
return self::TOK_WHITESPACE;
}
/**
* Parse identifiers
* @return int Token
* @internal Gets called with {@link $identifiers} characters
*/
protected function parse_identifier() {
$this->token_start = $this->pos;
while((++$this->pos < $this->size) && isset($this->identifiers[$this->doc[$this->pos]])) {}
--$this->pos;
return self::TOK_IDENTIFIER;
}
/**
* Continues to the next token
* @return int Next token ({@link TOK_NULL} if none)
*/
function next() {
$this->token_start = null;
if (++$this->pos < $this->size) {
if (isset($this->char_map[$this->doc[$this->pos]])) {
if (is_string($this->char_map[$this->doc[$this->pos]])) {
return ($this->token = $this->{$this->char_map[$this->doc[$this->pos]]}());
} else {
return ($this->token = $this->char_map[$this->doc[$this->pos]]);
}
} else {
return ($this->token = self::TOK_UNKNOWN);
}
} else {
return ($this->token = self::TOK_NULL);
}
}
/**
* Finds the next token, but skips whitespace
* @return int Next token ({@link TOK_NULL} if none)
*/
function next_no_whitespace() {
$this->token_start = null;
while (++$this->pos < $this->size) {
if (!isset($this->whitespace[$this->doc[$this->pos]])) {
if (isset($this->char_map[$this->doc[$this->pos]])) {
if (is_string($this->char_map[$this->doc[$this->pos]])) {
return ($this->token = $this->{$this->char_map[$this->doc[$this->pos]]}());
} else {
return ($this->token = $this->char_map[$this->doc[$this->pos]]);
}
} else {
return ($this->token = self::TOK_UNKNOWN);
}
} else {
$this->parse_linebreak();
}
}
return ($this->token = self::TOK_NULL);
}
/**
* Finds the next token using stop characters.
*
* Used like: next_search('abc') or next_search(array('a' => true, 'b' => true, 'c' => true));
* @param string|array $characters Characters to search for
* @param bool $callback Should the function check the charmap after finding a character?
* @return int Next token ({@link TOK_NULL} if none)
*/
function next_search($characters, $callback = true) {
$this->token_start = $this->pos;
if (!is_array($characters)) {
$characters = array_fill_keys(str_split($characters), true);
}
while(++$this->pos < $this->size) {
if (isset($characters[$this->doc[$this->pos]])) {
if ($callback && isset($this->char_map[$this->doc[$this->pos]])) {
if (is_string($this->char_map[$this->doc[$this->pos]])) {
return ($this->token = $this->{$this->char_map[$this->doc[$this->pos]]}());
} else {
return ($this->token = $this->char_map[$this->doc[$this->pos]]);
}
} else {
return ($this->token = self::TOK_UNKNOWN);
}
} else {
$this->parse_linebreak();
}
}
return ($this->token = self::TOK_NULL);
}
/**
* Finds the next token by searching for a string
* @param string $needle The needle that's being searched for
* @param bool $callback Should the function check the charmap after finding the needle?
* @return int Next token ({@link TOK_NULL} if none)
*/
function next_pos($needle, $callback = true) {
$this->token_start = $this->pos;
if (($this->pos < $this->size) && (($p = stripos($this->doc, $needle, $this->pos + 1)) !== false)) {
$len = $p - $this->pos - 1;
if ($len > 0) {
$str = substr($this->doc, $this->pos + 1, $len);
if (($l = strrpos($str, "\n")) !== false) {
++$this->line_pos[0];
$this->line_pos[1] = $l + $this->pos + 1;
$len -= $l;
if ($len > 0) {
$str = substr($str, 0, -$len);
$this->line_pos[0] += substr_count($str, "\n");
}
}
}
$this->pos = $p;
if ($callback && isset($this->char_map[$this->doc[$this->pos]])) {
if (is_string($this->char_map[$this->doc[$this->pos]])) {
return ($this->token = $this->{$this->char_map[$this->doc[$this->pos]]}());
} else {
return ($this->token = $this->char_map[$this->doc[$this->pos]]);
}
} else {
return ($this->token = self::TOK_UNKNOWN);
}
} else {
$this->pos = $this->size;
return ($this->token = self::TOK_NULL);
}
}
/**
* Expect a specific token or character. Adds error if token doesn't match.
* @param string|int $token Character or token to expect
* @param bool|int $do_next Go to next character before evaluating. 1 for next char, true to ignore whitespace
* @param bool|int $try_next Try next character if current doesn't match. 1 for next char, true to ignore whitespace
* @param bool|int $next_on_match Go to next character after evaluating. 1 for next char, true to ignore whitespace
* @return bool
*/
protected function expect($token, $do_next = true, $try_next = false, $next_on_match = 1) {
if ($do_next) {
if ($do_next === 1) {
$this->next();
} else {
$this->next_no_whitespace();
}
}
if (is_int($token)) {
if (($this->token !== $token) && ((!$try_next) || ((($try_next === 1) && ($this->next() !== $token)) || (($try_next === true) && ($this->next_no_whitespace() !== $token))))) {
$this->addError('Unexpected "'.$this->getTokenString().'"');
return false;
}
} else {
if (($this->doc[$this->pos] !== $token) && ((!$try_next) || (((($try_next === 1) && ($this->next() !== self::TOK_NULL)) || (($try_next === true) && ($this->next_no_whitespace() !== self::TOK_NULL))) && ($this->doc[$this->pos] !== $token)))) {
$this->addError('Expected "'.$token.'", but found "'.$this->getTokenString().'"');
return false;
}
}
if ($next_on_match) {
if ($next_on_match === 1) {
$this->next();
} else {
$this->next_no_whitespace();
}
}
return true;
}
}
?>
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