<?php
namespace Nextend\Framework\Asset\Css\Less;
use Exception;
use stdClass;
class LessParser {
static protected $nextBlockId = 0; // used to uniquely identify blocks
static protected $precedence = array(
'=<' => 0,
'>=' => 0,
'=' => 0,
'<' => 0,
'>' => 0,
'+' => 1,
'-' => 1,
'*' => 2,
'/' => 2,
'%' => 2,
);
static protected $whitePattern;
static protected $commentMulti;
static protected $commentSingle = "//";
static protected $commentMultiLeft = "/*";
static protected $commentMultiRight = "*/";
// regex string to match any of the operators
static protected $operatorString;
// these properties will supress division unless it's inside parenthases
static protected $supressDivisionProps = array(
'/border-radius$/i',
'/^font$/i'
);
protected $blockDirectives = array(
"font-face",
"keyframes",
"page",
"-moz-document"
);
protected $lineDirectives = array("charset");
/**
* if we are in parens we can be more liberal with whitespace around
* operators because it must evaluate to a single value and thus is less
* ambiguous.
*
* Consider:
* property1: 10 -5; // is two numbers, 10 and -5
* property2: (10 -5); // should evaluate to 5
*/
protected $inParens = false;
// caches preg escaped literals
static protected $literalCache = array();
public function __construct($lessc, $sourceName = null) {
$this->eatWhiteDefault = true;
// reference to less needed for vPrefix, mPrefix, and parentSelector
$this->lessc = $lessc;
$this->sourceName = $sourceName; // name used for error messages
$this->writeComments = false;
if (!self::$operatorString) {
self::$operatorString = '(' . implode('|', array_map(array(
LessCompiler::class,
'preg_quote'
), array_keys(self::$precedence))) . ')';
$commentSingle = LessCompiler::preg_quote(self::$commentSingle);
$commentMultiLeft = LessCompiler::preg_quote(self::$commentMultiLeft);
$commentMultiRight = LessCompiler::preg_quote(self::$commentMultiRight);
self::$commentMulti = $commentMultiLeft . '.*?' . $commentMultiRight;
self::$whitePattern = '/' . $commentSingle . '[^\n]*\s*|(' . self::$commentMulti . ')\s*|\s+/Ais';
}
}
public function parse($buffer) {
$this->count = 0;
$this->line = 1;
$this->env = null; // block stack
$this->buffer = $this->writeComments ? $buffer : $this->removeComments($buffer);
$this->pushSpecialBlock("root");
$this->eatWhiteDefault = true;
$this->seenComments = array();
// trim whitespace on head
// if (preg_match('/^\s+/', $this->buffer, $m)) {
// $this->line += substr_count($m[0], "\n");
// $this->buffer = ltrim($this->buffer);
// }
$this->whitespace();
// parse the entire file
$lastCount = $this->count;
while (false !== $this->parseChunk()) ;
if ($this->count != strlen($this->buffer)) $this->throwError();
// TODO report where the block was opened
if (!is_null($this->env->parent)) throw new Exception('parse error: unclosed block');
return $this->env;
}
/**
* Parse a single chunk off the head of the buffer and append it to the
* current parse environment.
* Returns false when the buffer is empty, or when there is an error.
*
* This function is called repeatedly until the entire document is
* parsed.
*
* This parser is most similar to a recursive descent parser. Single
* functions represent discrete grammatical rules for the language, and
* they are able to capture the text that represents those rules.
*
* Consider the function lessc::keyword(). (all parse functions are
* structured the same)
*
* The function takes a single reference argument. When calling the
* function it will attempt to match a keyword on the head of the buffer.
* If it is successful, it will place the keyword in the referenced
* argument, advance the position in the buffer, and return true. If it
* fails then it won't advance the buffer and it will return false.
*
* All of these parse functions are powered by lessc::match(), which behaves
* the same way, but takes a literal regular expression. Sometimes it is
* more convenient to use match instead of creating a new function.
*
* Because of the format of the functions, to parse an entire string of
* grammatical rules, you can chain them together using &&.
*
* But, if some of the rules in the chain succeed before one fails, then
* the buffer position will be left at an invalid state. In order to
* avoid this, lessc::seek() is used to remember and set buffer positions.
*
* Before parsing a chain, use $s = $this->seek() to remember the current
* position into $s. Then if a chain fails, use $this->seek($s) to
* go back where we started.
*/
protected function parseChunk() {
if (empty($this->buffer)) return false;
$s = $this->seek();
// setting a property
if ($this->keyword($key) && $this->assign() && $this->propertyValue($value, $key) && $this->end()) {
$this->append(array(
'assign',
$key,
$value
), $s);
return true;
} else {
$this->seek($s);
}
// look for special css blocks
if ($this->literal('@', false)) {
$this->count--;
// media
if ($this->literal('@media')) {
if (($this->mediaQueryList($mediaQueries) || true) && $this->literal('{')) {
$media = $this->pushSpecialBlock("media");
$media->queries = is_null($mediaQueries) ? array() : $mediaQueries;
return true;
} else {
$this->seek($s);
return false;
}
}
if ($this->literal("@", false) && $this->keyword($dirName)) {
if ($this->isDirective($dirName, $this->blockDirectives)) {
if (($this->openString("{", $dirValue, null, array(";")) || true) && $this->literal("{")) {
$dir = $this->pushSpecialBlock("directive");
$dir->name = $dirName;
if (isset($dirValue)) $dir->value = $dirValue;
return true;
}
} elseif ($this->isDirective($dirName, $this->lineDirectives)) {
if ($this->propertyValue($dirValue) && $this->end()) {
$this->append(array(
"directive",
$dirName,
$dirValue
));
return true;
}
}
}
$this->seek($s);
}
// setting a variable
if ($this->variable($var) && $this->assign() && $this->propertyValue($value) && $this->end()) {
$this->append(array(
'assign',
$var,
$value
), $s);
return true;
} else {
$this->seek($s);
}
if ($this->import($importValue)) {
$this->append($importValue, $s);
return true;
}
// opening parametric mixin
if ($this->tag($tag, true) && $this->argumentDef($args, $isVararg) && ($this->guards($guards) || true) && $this->literal('{')) {
$block = $this->pushBlock($this->fixTags(array($tag)));
$block->args = $args;
$block->isVararg = $isVararg;
if (!empty($guards)) $block->guards = $guards;
return true;
} else {
$this->seek($s);
}
// opening a simple block
if ($this->tags($tags) && $this->literal('{')) {
$tags = $this->fixTags($tags);
$this->pushBlock($tags);
return true;
} else {
$this->seek($s);
}
// closing a block
if ($this->literal('}', false)) {
try {
$block = $this->pop();
} catch (Exception $e) {
$this->seek($s);
$this->throwError($e->getMessage());
}
$hidden = false;
if (is_null($block->type)) {
$hidden = true;
if (!isset($block->args)) {
foreach ($block->tags as $tag) {
if (!is_string($tag) || $tag[0] != $this->lessc->mPrefix) {
$hidden = false;
break;
}
}
}
foreach ($block->tags as $tag) {
if (is_string($tag)) {
$this->env->children[$tag][] = $block;
}
}
}
if (!$hidden) {
$this->append(array(
'block',
$block
), $s);
}
// this is done here so comments aren't bundled into he block that
// was just closed
$this->whitespace();
return true;
}
// mixin
if ($this->mixinTags($tags) && ($this->argumentValues($argv) || true) && ($this->keyword($suffix) || true) && $this->end()) {
$tags = $this->fixTags($tags);
$this->append(array(
'mixin',
$tags,
$argv,
$suffix
), $s);
return true;
} else {
$this->seek($s);
}
// spare ;
if ($this->literal(';')) return true;
return false; // got nothing, throw error
}
protected function isDirective($dirname, $directives) {
// TODO: cache pattern in parser
$pattern = implode("|", array_map(array(
LessCompiler::class,
"preg_quote"
), $directives));
$pattern = '/^(-[a-z-]+-)?(' . $pattern . ')$/i';
return preg_match($pattern, $dirname);
}
protected function fixTags($tags) {
// move @ tags out of variable namespace
foreach ($tags as &$tag) {
if ($tag[0] == $this->lessc->vPrefix) $tag[0] = $this->lessc->mPrefix;
}
return $tags;
}
// a list of expressions
protected function expressionList(&$exps) {
$values = array();
while ($this->expression($exp)) {
$values[] = $exp;
}
if (count($values) == 0) return false;
$exps = LessCompiler::compressList($values, ' ');
return true;
}
/**
* Attempt to consume an expression.
*
* @link http://en.wikipedia.org/wiki/Operator-precedence_parser#Pseudo-code
*/
protected function expression(&$out) {
if ($this->value($lhs)) {
$out = $this->expHelper($lhs, 0);
// look for / shorthand
if (!empty($this->env->supressedDivision)) {
unset($this->env->supressedDivision);
$s = $this->seek();
if ($this->literal("/") && $this->value($rhs)) {
$out = array(
"list",
"",
array(
$out,
array(
"keyword",
"/"
),
$rhs
)
);
} else {
$this->seek($s);
}
}
return true;
}
return false;
}
/**
* recursively parse infix equation with $lhs at precedence $minP
*/
protected function expHelper($lhs, $minP) {
$this->inExp = true;
$ss = $this->seek();
while (true) {
$whiteBefore = isset($this->buffer[$this->count - 1]) && preg_match('/^\\s+$/', $this->buffer[$this->count - 1]);
// If there is whitespace before the operator, then we require
// whitespace after the operator for it to be an expression
$needWhite = $whiteBefore && !$this->inParens;
if ($this->match(self::$operatorString . ($needWhite ? '\s' : ''), $m) && self::$precedence[$m[1]] >= $minP) {
if (!$this->inParens && isset($this->env->currentProperty) && $m[1] == "/" && empty($this->env->supressedDivision)) {
foreach (self::$supressDivisionProps as $pattern) {
if (preg_match($pattern, $this->env->currentProperty)) {
$this->env->supressedDivision = true;
break 2;
}
}
}
$whiteAfter = isset($this->buffer[$this->count - 1]) && preg_match('/^\\s+$/', $this->buffer[$this->count - 1]);
if (!$this->value($rhs)) break;
// peek for next operator to see what to do with rhs
if ($this->peek(self::$operatorString, $next) && self::$precedence[$next[1]] > self::$precedence[$m[1]]) {
$rhs = $this->expHelper($rhs, self::$precedence[$next[1]]);
}
$lhs = array(
'expression',
$m[1],
$lhs,
$rhs,
$whiteBefore,
$whiteAfter
);
$ss = $this->seek();
continue;
}
break;
}
$this->seek($ss);
return $lhs;
}
// consume a list of values for a property
public function propertyValue(&$value, $keyName = null) {
$values = array();
if ($keyName !== null) $this->env->currentProperty = $keyName;
$s = null;
while ($this->expressionList($v)) {
$values[] = $v;
$s = $this->seek();
if (!$this->literal(',')) break;
}
if ($s) $this->seek($s);
if ($keyName !== null) unset($this->env->currentProperty);
if (count($values) == 0) return false;
$value = LessCompiler::compressList($values, ', ');
return true;
}
protected function parenValue(&$out) {
$s = $this->seek();
// speed shortcut
if (isset($this->buffer[$this->count]) && $this->buffer[$this->count] != "(") {
return false;
}
$inParens = $this->inParens;
if ($this->literal("(") && ($this->inParens = true) && $this->expression($exp) && $this->literal(")")) {
$out = $exp;
$this->inParens = $inParens;
return true;
} else {
$this->inParens = $inParens;
$this->seek($s);
}
return false;
}
// a single value
protected function value(&$value) {
$s = $this->seek();
// speed shortcut
if (isset($this->buffer[$this->count]) && $this->buffer[$this->count] == "-") {
// negation
if ($this->literal("-", false) && (($this->variable($inner) && $inner = array(
"variable",
$inner
)) || $this->unit($inner) || $this->parenValue($inner))) {
$value = array(
"unary",
"-",
$inner
);
return true;
} else {
$this->seek($s);
}
}
if ($this->parenValue($value)) return true;
if ($this->unit($value)) return true;
if ($this->color($value)) return true;
if ($this->func($value)) return true;
if ($this->_string($value)) return true;
if ($this->keyword($word)) {
$value = array(
'keyword',
$word
);
return true;
}
// try a variable
if ($this->variable($var)) {
$value = array(
'variable',
$var
);
return true;
}
// unquote string (should this work on any type?
if ($this->literal("~") && $this->_string($str)) {
$value = array(
"escape",
$str
);
return true;
} else {
$this->seek($s);
}
// css hack: \0
if ($this->literal('\\') && $this->match('([0-9]+)', $m)) {
$value = array(
'keyword',
'\\' . $m[1]
);
return true;
} else {
$this->seek($s);
}
return false;
}
// an import statement
protected function import(&$out) {
$s = $this->seek();
if (!$this->literal('@import')) return false;
// @import "something.css" media;
// @import url("something.css") media;
// @import url(something.css) media;
if ($this->propertyValue($value)) {
$out = array(
"import",
$value
);
return true;
}
}
protected function mediaQueryList(&$out) {
if ($this->genericList($list, "mediaQuery", ",", false)) {
$out = $list[2];
return true;
}
return false;
}
protected function mediaQuery(&$out) {
$s = $this->seek();
$expressions = null;
$parts = array();
if (($this->literal("only") && ($only = true) || $this->literal("not") && ($not = true) || true) && $this->keyword($mediaType)) {
$prop = array("mediaType");
if (isset($only)) $prop[] = "only";
if (isset($not)) $prop[] = "not";
$prop[] = $mediaType;
$parts[] = $prop;
} else {
$this->seek($s);
}
if (!empty($mediaType) && !$this->literal("and")) {
// ~
} else {
$this->genericList($expressions, "mediaExpression", "and", false);
if (is_array($expressions)) $parts = array_merge($parts, $expressions[2]);
}
if (count($parts) == 0) {
$this->seek($s);
return false;
}
$out = $parts;
return true;
}
protected function mediaExpression(&$out) {
$s = $this->seek();
$value = null;
if ($this->literal("(") && $this->keyword($feature) && ($this->literal(":") && $this->expression($value) || true) && $this->literal(")")) {
$out = array(
"mediaExp",
$feature
);
if ($value) $out[] = $value;
return true;
} elseif ($this->variable($variable)) {
$out = array(
'variable',
$variable
);
return true;
}
$this->seek($s);
return false;
}
// an unbounded string stopped by $end
protected function openString($end, &$out, $nestingOpen = null, $rejectStrs = null) {
$oldWhite = $this->eatWhiteDefault;
$this->eatWhiteDefault = false;
$stop = array(
"'",
'"',
"@{",
$end
);
$stop = array_map(array(
LessCompiler::class,
"preg_quote"
), $stop);
// $stop[] = self::$commentMulti;
if (!is_null($rejectStrs)) {
$stop = array_merge($stop, $rejectStrs);
}
$patt = '(.*?)(' . implode("|", $stop) . ')';
$nestingLevel = 0;
$content = array();
while ($this->match($patt, $m, false)) {
if (!empty($m[1])) {
$content[] = $m[1];
if ($nestingOpen) {
$nestingLevel += substr_count($m[1], $nestingOpen);
}
}
$tok = $m[2];
$this->count -= strlen($tok);
if ($tok == $end) {
if ($nestingLevel == 0) {
break;
} else {
$nestingLevel--;
}
}
if (($tok == "'" || $tok == '"') && $this->_string($str)) {
$content[] = $str;
continue;
}
if ($tok == "@{" && $this->interpolation($inter)) {
$content[] = $inter;
continue;
}
if (!empty($rejectStrs) && in_array($tok, $rejectStrs)) {
$ount = null;
break;
}
$content[] = $tok;
$this->count += strlen($tok);
}
$this->eatWhiteDefault = $oldWhite;
if (count($content) == 0) return false;
// trim the end
if (is_string(end($content))) {
$content[count($content) - 1] = rtrim(end($content));
}
$out = array(
"string",
"",
$content
);
return true;
}
protected function _string(&$out) {
$s = $this->seek();
if ($this->literal('"', false)) {
$delim = '"';
} elseif ($this->literal("'", false)) {
$delim = "'";
} else {
return false;
}
$content = array();
// look for either ending delim , escape, or string interpolation
$patt = '([^\n]*?)(@\{|\\\\|' . LessCompiler::preg_quote($delim) . ')';
$oldWhite = $this->eatWhiteDefault;
$this->eatWhiteDefault = false;
while ($this->match($patt, $m, false)) {
$content[] = $m[1];
if ($m[2] == "@{") {
$this->count -= strlen($m[2]);
if ($this->interpolation($inter)) {
$content[] = $inter;
} else {
$this->count += strlen($m[2]);
$content[] = "@{"; // ignore it
}
} elseif ($m[2] == '\\') {
$content[] = $m[2];
if ($this->literal($delim, false)) {
$content[] = $delim;
}
} else {
$this->count -= strlen($delim);
break; // delim
}
}
$this->eatWhiteDefault = $oldWhite;
if ($this->literal($delim)) {
$out = array(
"string",
$delim,
$content
);
return true;
}
$this->seek($s);
return false;
}
protected function interpolation(&$out) {
$oldWhite = $this->eatWhiteDefault;
$this->eatWhiteDefault = true;
$s = $this->seek();
if ($this->literal("@{") && $this->openString("}", $interp, null, array(
"'",
'"',
";"
)) && $this->literal("}", false)) {
$out = array(
"interpolate",
$interp
);
$this->eatWhiteDefault = $oldWhite;
if ($this->eatWhiteDefault) $this->whitespace();
return true;
}
$this->eatWhiteDefault = $oldWhite;
$this->seek($s);
return false;
}
protected function unit(&$unit) {
// speed shortcut
if (isset($this->buffer[$this->count])) {
$char = $this->buffer[$this->count];
if (!preg_match('/^[0-9]+$/', $char) && $char != ".") return false;
}
if ($this->match('([0-9]+(?:\.[0-9]*)?|\.[0-9]+)([%a-zA-Z]+)?', $m)) {
$unit = array(
"number",
$m[1],
empty($m[2]) ? "" : $m[2]
);
return true;
}
return false;
}
// a # color
protected function color(&$out) {
if ($this->match('(#(?:[0-9a-f]{8}|[0-9a-f]{6}|[0-9a-f]{3}))', $m)) {
if (strlen($m[1]) > 7) {
$out = array(
"string",
"",
array($m[1])
);
} else {
$out = array(
"raw_color",
$m[1]
);
}
return true;
}
return false;
}
// consume a list of property values delimited by ; and wrapped in ()
protected function argumentValues(&$args, $delim = ',') {
$s = $this->seek();
if (!$this->literal('(')) return false;
$values = array();
while (true) {
if ($this->expressionList($value)) $values[] = $value;
if (!$this->literal($delim)) break; else {
if ($value == null) $values[] = null;
$value = null;
}
}
if (!$this->literal(')')) {
$this->seek($s);
return false;
}
$args = $values;
return true;
}
// consume an argument definition list surrounded by ()
// each argument is a variable name with optional value
// or at the end a ... or a variable named followed by ...
protected function argumentDef(&$args, &$isVararg, $delim = ',') {
$s = $this->seek();
if (!$this->literal('(')) return false;
$values = array();
$isVararg = false;
while (true) {
if ($this->literal("...")) {
$isVararg = true;
break;
}
if ($this->variable($vname)) {
$arg = array(
"arg",
$vname
);
$ss = $this->seek();
if ($this->assign() && $this->expressionList($value)) {
$arg[] = $value;
} else {
$this->seek($ss);
if ($this->literal("...")) {
$arg[0] = "rest";
$isVararg = true;
}
}
$values[] = $arg;
if ($isVararg) break;
continue;
}
if ($this->value($literal)) {
$values[] = array(
"lit",
$literal
);
}
if (!$this->literal($delim)) break;
}
if (!$this->literal(')')) {
$this->seek($s);
return false;
}
$args = $values;
return true;
}
// consume a list of tags
// this accepts a hanging delimiter
protected function tags(&$tags, $simple = false, $delim = ',') {
$tags = array();
while ($this->tag($tt, $simple)) {
$tags[] = $tt;
if (!$this->literal($delim)) break;
}
if (count($tags) == 0) return false;
return true;
}
// list of tags of specifying mixin path
// optionally separated by > (lazy, accepts extra >)
protected function mixinTags(&$tags) {
$s = $this->seek();
$tags = array();
while ($this->tag($tt, true)) {
$tags[] = $tt;
$this->literal(">");
}
if (count($tags) == 0) return false;
return true;
}
// a bracketed value (contained within in a tag definition)
protected function tagBracket(&$value) {
// speed shortcut
if (isset($this->buffer[$this->count]) && $this->buffer[$this->count] != "[") {
return false;
}
$s = $this->seek();
if ($this->literal('[') && $this->to(']', $c, true) && $this->literal(']', false)) {
$value = '[' . $c . ']';
// whitespace?
if ($this->whitespace()) $value .= " ";
// escape parent selector, (yuck)
$value = str_replace($this->lessc->parentSelector, "$&$", $value);
return true;
}
$this->seek($s);
return false;
}
protected function tagExpression(&$value) {
$s = $this->seek();
if ($this->literal("(") && $this->expression($exp) && $this->literal(")")) {
$value = array(
'exp',
$exp
);
return true;
}
$this->seek($s);
return false;
}
// a space separated list of selectors
protected function tag(&$tag, $simple = false) {
if ($simple) $chars = '^@,:;{}\][>\(\) "\''; else
$chars = '^@,;{}["\'';
$s = $this->seek();
if (!$simple && $this->tagExpression($tag)) {
return true;
}
$hasExpression = false;
$parts = array();
while ($this->tagBracket($first)) $parts[] = $first;
$oldWhite = $this->eatWhiteDefault;
$this->eatWhiteDefault = false;
while (true) {
if ($this->match('([' . $chars . '0-9][' . $chars . ']*)', $m)) {
$parts[] = $m[1];
if ($simple) break;
while ($this->tagBracket($brack)) {
$parts[] = $brack;
}
continue;
}
if (isset($this->buffer[$this->count]) && $this->buffer[$this->count] == "@") {
if ($this->interpolation($interp)) {
$hasExpression = true;
$interp[2] = true; // don't unescape
$parts[] = $interp;
continue;
}
if ($this->literal("@")) {
$parts[] = "@";
continue;
}
}
if ($this->unit($unit)) { // for keyframes
$parts[] = $unit[1];
$parts[] = $unit[2];
continue;
}
break;
}
$this->eatWhiteDefault = $oldWhite;
if (!$parts) {
$this->seek($s);
return false;
}
if ($hasExpression) {
$tag = array(
"exp",
array(
"string",
"",
$parts
)
);
} else {
$tag = trim(implode($parts));
}
$this->whitespace();
return true;
}
// a css function
protected function func(&$func) {
$s = $this->seek();
if ($this->match('(%|[\w\-_][\w\-_:\.]+|[\w_])', $m) && $this->literal('(')) {
$fname = $m[1];
$sPreArgs = $this->seek();
$args = array();
while (true) {
$ss = $this->seek();
// this ugly nonsense is for ie filter properties
if ($this->keyword($name) && $this->literal('=') && $this->expressionList($value)) {
$args[] = array(
"string",
"",
array(
$name,
"=",
$value
)
);
} else {
$this->seek($ss);
if ($this->expressionList($value)) {
$args[] = $value;
}
}
if (!$this->literal(',')) break;
}
$args = array(
'list',
',',
$args
);
if ($this->literal(')')) {
$func = array(
'function',
$fname,
$args
);
return true;
} elseif ($fname == 'url') {
// couldn't parse and in url? treat as string
$this->seek($sPreArgs);
if ($this->openString(")", $string) && $this->literal(")")) {
$func = array(
'function',
$fname,
$string
);
return true;
}
}
}
$this->seek($s);
return false;
}
// consume a less variable
protected function variable(&$name) {
$s = $this->seek();
if ($this->literal($this->lessc->vPrefix, false) && ($this->variable($sub) || $this->keyword($name))) {
if (!empty($sub)) {
$name = array(
'variable',
$sub
);
} else {
$name = $this->lessc->vPrefix . $name;
}
return true;
}
$name = null;
$this->seek($s);
return false;
}
/**
* Consume an assignment operator
* Can optionally take a name that will be set to the current property name
*/
protected function assign($name = null) {
if ($name) $this->currentProperty = $name;
return $this->literal(':') || $this->literal('=');
}
// consume a keyword
protected function keyword(&$word) {
if ($this->match('([\w_\-\*!"][\w\-_"]*)', $m)) {
$word = $m[1];
return true;
}
return false;
}
// consume an end of statement delimiter
protected function end() {
if ($this->literal(';')) {
return true;
} elseif ($this->count == strlen($this->buffer) || $this->buffer[$this->count] == '}') {
// if there is end of file or a closing block next then we don't need a ;
return true;
}
return false;
}
protected function guards(&$guards) {
$s = $this->seek();
if (!$this->literal("when")) {
$this->seek($s);
return false;
}
$guards = array();
while ($this->guardGroup($g)) {
$guards[] = $g;
if (!$this->literal(",")) break;
}
if (count($guards) == 0) {
$guards = null;
$this->seek($s);
return false;
}
return true;
}
// a bunch of guards that are and'd together
// TODO rename to guardGroup
protected function guardGroup(&$guardGroup) {
$s = $this->seek();
$guardGroup = array();
while ($this->guard($guard)) {
$guardGroup[] = $guard;
if (!$this->literal("and")) break;
}
if (count($guardGroup) == 0) {
$guardGroup = null;
$this->seek($s);
return false;
}
return true;
}
protected function guard(&$guard) {
$s = $this->seek();
$negate = $this->literal("not");
if ($this->literal("(") && $this->expression($exp) && $this->literal(")")) {
$guard = $exp;
if ($negate) $guard = array(
"negate",
$guard
);
return true;
}
$this->seek($s);
return false;
}
/* raw parsing functions */
protected function literal($what, $eatWhitespace = null) {
if ($eatWhitespace === null) $eatWhitespace = $this->eatWhiteDefault;
// shortcut on single letter
if (!isset($what[1]) && isset($this->buffer[$this->count])) {
if ($this->buffer[$this->count] == $what) {
if (!$eatWhitespace) {
$this->count++;
return true;
}
// goes below...
} else {
return false;
}
}
if (!isset(self::$literalCache[$what])) {
self::$literalCache[$what] = LessCompiler::preg_quote($what);
}
return $this->match(self::$literalCache[$what], $m, $eatWhitespace);
}
protected function genericList(&$out, $parseItem, $delim = "", $flatten = true) {
$s = $this->seek();
$items = array();
while ($this->$parseItem($value)) {
$items[] = $value;
if ($delim) {
if (!$this->literal($delim)) break;
}
}
if (count($items) == 0) {
$this->seek($s);
return false;
}
if ($flatten && count($items) == 1) {
$out = $items[0];
} else {
$out = array(
"list",
$delim,
$items
);
}
return true;
}
// advance counter to next occurrence of $what
// $until - don't include $what in advance
// $allowNewline, if string, will be used as valid char set
protected function to($what, &$out, $until = false, $allowNewline = false) {
if (is_string($allowNewline)) {
$validChars = $allowNewline;
} else {
$validChars = $allowNewline ? "." : "[^\n]";
}
if (!$this->match('(' . $validChars . '*?)' . LessCompiler::preg_quote($what), $m, !$until)) return false;
if ($until) $this->count -= strlen($what); // give back $what
$out = $m[1];
return true;
}
// try to match something on head of buffer
protected function match($regex, &$out, $eatWhitespace = null) {
if ($eatWhitespace === null) $eatWhitespace = $this->eatWhiteDefault;
$r = '/' . $regex . ($eatWhitespace && !$this->writeComments ? '\s*' : '') . '/Ais';
if (preg_match($r, $this->buffer, $out, 0, $this->count)) {
$this->count += strlen($out[0]);
if ($eatWhitespace && $this->writeComments) $this->whitespace();
return true;
}
return false;
}
// match some whitespace
protected function whitespace() {
if ($this->writeComments) {
$gotWhite = false;
while (preg_match(self::$whitePattern, $this->buffer, $m, 0, $this->count)) {
if (isset($m[1]) && empty($this->commentsSeen[$this->count])) {
$this->append(array(
"comment",
$m[1]
));
$this->commentsSeen[$this->count] = true;
}
$this->count += strlen($m[0]);
$gotWhite = true;
}
return $gotWhite;
} else {
$this->match("", $m);
return strlen($m[0]) > 0;
}
}
// match something without consuming it
protected function peek($regex, &$out = null, $from = null) {
if (is_null($from)) $from = $this->count;
$r = '/' . $regex . '/Ais';
$result = preg_match($r, $this->buffer, $out, 0, $from);
return $result;
}
// seek to a spot in the buffer or return where we are on no argument
protected function seek($where = null) {
if ($where === null) return $this->count; else $this->count = $where;
return true;
}
/* misc functions */
public function throwError($msg = "parse error", $count = null) {
$count = is_null($count) ? $this->count : $count;
$line = $this->line + substr_count(substr($this->buffer, 0, $count), "\n");
if (!empty($this->sourceName)) {
$loc = "$this->sourceName on line $line";
} else {
$loc = "line: $line";
}
// TODO this depends on $this->count
if ($this->peek("(.*?)(\n|$)", $m, $count)) {
throw new Exception("$msg: failed at `$m[1]` $loc<br>FILE: <strong>{$this->lessc->sourceParser->sourceName}</strong>");
} else {
throw new Exception("$msg: $loc<br>FILE: <strong>{$this->lessc->sourceParser->sourceName}</strong>");
}
}
protected function pushBlock($selectors = null, $type = null) {
$b = new stdclass;
$b->parent = $this->env;
$b->type = $type;
$b->id = self::$nextBlockId++;
$b->isVararg = false; // TODO: kill me from here
$b->tags = $selectors;
$b->props = array();
$b->children = array();
$this->env = $b;
return $b;
}
// push a block that doesn't multiply tags
protected function pushSpecialBlock($type) {
return $this->pushBlock(null, $type);
}
// append a property to the current block
protected function append($prop, $pos = null) {
if ($pos !== null) $prop[-1] = $pos;
$this->env->props[] = $prop;
}
// pop something off the stack
protected function pop() {
$old = $this->env;
$this->env = $this->env->parent;
return $old;
}
// remove comments from $text
// todo: make it work for all functions, not just url
protected function removeComments($text) {
$look = array(
'url(',
'//',
'/*',
'"',
"'"
);
$out = '';
$min = null;
while (true) {
// find the next item
foreach ($look as $token) {
$pos = strpos($text, $token);
if ($pos !== false) {
if (!isset($min) || $pos < $min[1]) $min = array(
$token,
$pos
);
}
}
if (is_null($min)) break;
$count = $min[1];
$skip = 0;
$newlines = 0;
switch ($min[0]) {
case 'url(':
if (preg_match('/url\(.*?\)/', $text, $m, 0, $count)) $count += strlen($m[0]) - strlen($min[0]);
break;
case '"':
case "'":
if (preg_match('/' . $min[0] . '.*?' . $min[0] . '/', $text, $m, 0, $count)) $count += strlen($m[0]) - 1;
break;
case '//':
$skip = strpos($text, "\n", $count);
if ($skip === false) $skip = strlen($text) - $count; else $skip -= $count;
break;
case '/*':
if (preg_match('/\/\*.*?\*\//s', $text, $m, 0, $count)) {
$skip = strlen($m[0]);
$newlines = substr_count($m[0], "\n");
}
break;
}
if ($skip == 0) $count += strlen($min[0]);
$out .= substr($text, 0, $count) . str_repeat("\n", $newlines);
$text = substr($text, $count + $skip);
$min = null;
}
return $out . $text;
}
}