<?php

/**
 * Chunk Exception
 *
 * @package Less
 * @subpackage exception
 */
class Less_Exception_Chunk extends Less_Exception_Parser{


	protected $parserCurrentIndex = 0;

	protected $emitFrom = 0;

	protected $input_len;


	/**
	 * Constructor
	 *
	 * @param string $input
	 * @param Exception $previous Previous exception
	 * @param integer $index The current parser index
	 * @param Less_FileInfo|string $currentFile The file
	 * @param integer $code The exception code
	 */
	public function __construct($input, Exception $previous = null, $index = null, $currentFile = null, $code = 0){

		$this->message = 'ParseError: Unexpected input'; //default message

		$this->index = $index;

		$this->currentFile = $currentFile;

		$this->input = $input;
		$this->input_len = strlen($input);

		$this->Chunks();
		$this->genMessage();
	}


	/**
	 * See less.js chunks()
	 * We don't actually need the chunks
	 *
	 */
	protected function Chunks(){
		$level = 0;
		$parenLevel = 0;
		$lastMultiCommentEndBrace = null;
		$lastOpening = null;
		$lastMultiComment = null;
		$lastParen = null;

		for( $this->parserCurrentIndex = 0; $this->parserCurrentIndex < $this->input_len; $this->parserCurrentIndex++ ){
			$cc = $this->CharCode($this->parserCurrentIndex);
			if ((($cc >= 97) && ($cc <= 122)) || ($cc < 34)) {
				// a-z or whitespace
				continue;
			}

			switch ($cc) {

				// (
				case 40:
					$parenLevel++;
					$lastParen = $this->parserCurrentIndex;
					continue 2;

				// )
				case 41:
					$parenLevel--;
					if( $parenLevel < 0 ){
						return $this->fail("missing opening `(`");
					}
					continue 2;

				// ;
				case 59:
					//if (!$parenLevel) { $this->emitChunk();	}
					continue 2;

				// {
				case 123:
					$level++;
					$lastOpening = $this->parserCurrentIndex;
					continue 2;

				// }
				case 125:
					$level--;
					if( $level < 0 ){
						return $this->fail("missing opening `{`");

					}
					//if (!$level && !$parenLevel) { $this->emitChunk(); }
					continue 2;
				// \
				case 92:
					if ($this->parserCurrentIndex < $this->input_len - 1) { $this->parserCurrentIndex++; continue 2; }
					return $this->fail("unescaped `\\`");

				// ", ' and `
				case 34:
				case 39:
				case 96:
					$matched = 0;
					$currentChunkStartIndex = $this->parserCurrentIndex;
					for ($this->parserCurrentIndex = $this->parserCurrentIndex + 1; $this->parserCurrentIndex < $this->input_len; $this->parserCurrentIndex++) {
						$cc2 = $this->CharCode($this->parserCurrentIndex);
						if ($cc2 > 96) { continue; }
						if ($cc2 == $cc) { $matched = 1; break; }
						if ($cc2 == 92) {        // \
							if ($this->parserCurrentIndex == $this->input_len - 1) {
								return $this->fail("unescaped `\\`");
							}
							$this->parserCurrentIndex++;
						}
					}
					if ($matched) { continue 2; }
					return $this->fail("unmatched `" . chr($cc) . "`", $currentChunkStartIndex);

				// /, check for comment
				case 47:
					if ($parenLevel || ($this->parserCurrentIndex == $this->input_len - 1)) { continue 2; }
					$cc2 = $this->CharCode($this->parserCurrentIndex+1);
					if ($cc2 == 47) {
						// //, find lnfeed
						for ($this->parserCurrentIndex = $this->parserCurrentIndex + 2; $this->parserCurrentIndex < $this->input_len; $this->parserCurrentIndex++) {
							$cc2 = $this->CharCode($this->parserCurrentIndex);
							if (($cc2 <= 13) && (($cc2 == 10) || ($cc2 == 13))) { break; }
						}
					} else if ($cc2 == 42) {
						// /*, find */
						$lastMultiComment = $currentChunkStartIndex = $this->parserCurrentIndex;
						for ($this->parserCurrentIndex = $this->parserCurrentIndex + 2; $this->parserCurrentIndex < $this->input_len - 1; $this->parserCurrentIndex++) {
							$cc2 = $this->CharCode($this->parserCurrentIndex);
							if ($cc2 == 125) { $lastMultiCommentEndBrace = $this->parserCurrentIndex; }
							if ($cc2 != 42) { continue; }
							if ($this->CharCode($this->parserCurrentIndex+1) == 47) { break; }
						}
						if ($this->parserCurrentIndex == $this->input_len - 1) {
							return $this->fail("missing closing `*/`", $currentChunkStartIndex);
						}
					}
					continue 2;

				// *, check for unmatched */
				case 42:
					if (($this->parserCurrentIndex < $this->input_len - 1) && ($this->CharCode($this->parserCurrentIndex+1) == 47)) {
						return $this->fail("unmatched `/*`");
					}
					continue 2;
			}
		}

		if( $level !== 0 ){
			if( ($lastMultiComment > $lastOpening) && ($lastMultiCommentEndBrace > $lastMultiComment) ){
				return $this->fail("missing closing `}` or `*/`", $lastOpening);
			} else {
				return $this->fail("missing closing `}`", $lastOpening);
			}
		} else if ( $parenLevel !== 0 ){
			return $this->fail("missing closing `)`", $lastParen);
		}


		//chunk didn't fail


		//$this->emitChunk(true);
	}

	public function CharCode($pos){
		return ord($this->input[$pos]);
	}


	public function fail( $msg, $index = null ){

		if( !$index ){
			$this->index = $this->parserCurrentIndex;
		}else{
			$this->index = $index;
		}
		$this->message = 'ParseError: '.$msg;
	}


	/*
	function emitChunk( $force = false ){
		$len = $this->parserCurrentIndex - $this->emitFrom;
		if ((($len < 512) && !$force) || !$len) {
			return;
		}
		$chunks[] = substr($this->input, $this->emitFrom, $this->parserCurrentIndex + 1 - $this->emitFrom );
		$this->emitFrom = $this->parserCurrentIndex + 1;
	}
	*/

}
