<?php

class parseCSV {

	/**
	 * Configuration
	 * - set these options with $object->var_name = 'value';
	 */
	
	# use first line/entry as field names
	var $heading = true;
	
	# override field names
	var $fields = array();
	
	# sort entries by this field
	var $sort_by = null;
	var $sort_reverse = false;
	
	# sort behavior passed to ksort/krsort functions
	# regular = SORT_REGULAR
	# numeric = SORT_NUMERIC
	# string  = SORT_STRING
	var $sort_type = null;
	
	# delimiter (comma) and enclosure (double quote)
	var $delimiter = ',';
	var $enclosure = '"';
	
	# basic SQL-like conditions for row matching
	var $conditions = null;
	
	# number of rows to ignore from beginning of data
	var $offset = null;
	
	# limits the number of returned rows to specified amount
	var $limit = null;
	
	# number of rows to analyze when attempting to auto-detect delimiter
	var $auto_depth = 15;
	
	# characters to ignore when attempting to auto-detect delimiter
	var $auto_non_chars = "a-zA-Z0-9\n\r";
	
	# preferred delimiter characters, only used when all filtering method
	# returns multiple possible delimiters (happens very rarely)
	var $auto_preferred = ",;\t.:|";
	
	# character encoding options
	var $convert_encoding = false;
	var $input_encoding = 'ISO-8859-1';
	var $output_encoding = 'ISO-8859-1';
	
	# used by unparse(), save(), and output() functions
	var $linefeed = "\r\n";
	
	# only used by output() function
	var $output_delimiter = ',';
	var $output_filename = 'data.csv';
	
	# keep raw file data in memory after successful parsing (useful for debugging)
	var $keep_file_data = false;
	
	/**
	 * Internal variables
	 */
	
	# current file
	var $file;
	
	# loaded file contents
	var $file_data;
	
	# error while parsing input data
	#  0 = No errors found. Everything should be fine :)
	#  1 = Hopefully correctable syntax error was found.
	#  2 = Enclosure character (double quote by default)
	#      was found in non-enclosed field. This means
	#      the file is either corrupt, or does not
	#      standard CSV formatting. Please validate
	#      the parsed data yourself.
	var $error = 0;
	
	# detailed error info
	var $error_info = array();
	
	# array of field values in data parsed
	var $titles = array();
	
	# two dimentional array of CSV data
	var $data = array();
	
	
	/**
	 * Constructor
	 * @param   input   CSV file or string
	 * @return  nothing
	 */
	function __construct($input = null, $offset = null, $limit = null, $conditions = null) {
		if ( $offset !== null ) $this->offset = $offset;
		if ( $limit !== null ) $this->limit = $limit;
		if ( count($conditions) > 0 ) $this->conditions = $conditions;
		if ( !empty($input) ) $this->parse($input);
	}
	
	
	// ==============================================
	// ----- [ Main Functions ] ---------------------
	// ==============================================
	
	/**
	 * Parse CSV file or string
	 * @param   input   CSV file or string
	 * @return  nothing
	 */
	function parse ($input = null, $offset = null, $limit = null, $conditions = null) {
		if ( $input === null ) $input = $this->file;
		if ( !empty($input) ) {
			if ( $offset !== null ) $this->offset = $offset;
			if ( $limit !== null ) $this->limit = $limit;
			if ( count($conditions) > 0 ) $this->conditions = $conditions;
			if ( is_readable($input) ) {
				$this->data = $this->parse_file($input);
			} else {
				$this->file_data = &$input;
				$this->data = $this->parse_string();
			}
			if ( $this->data === false ) return false;
		}
		return true;
	}
	
	/**
	 * Save changes, or new file and/or data
	 * @param   file     file to save to
	 * @param   data     2D array with data
	 * @param   append   append current data to end of target CSV if exists
	 * @param   fields   field names
	 * @return  true or false
	 */
	function save ($file = null, $data = array(), $append = false, $fields = array()) {
		if ( empty($file) ) $file = &$this->file;
		$mode = ( $append ) ? 'at' : 'wt' ;
		$is_php = ( preg_match('/\.php$/i', $file) ) ? true : false ;
		return $this->_wfile($file, $this->unparse($data, $fields, $append, $is_php), $mode);
	}
	
	/**
	 * Generate CSV based string for output
	 * @param   filename    if specified, headers and data will be output directly to browser as a downloable file
	 * @param   data        2D array with data
	 * @param   fields      field names
	 * @param   delimiter   delimiter used to separate data
	 * @return  CSV data using delimiter of choice, or default
	 */
	function output ($filename = null, $data = array(), $fields = array(), $delimiter = null) {
		if ( empty($filename) ) $filename = $this->output_filename;
		if ( $delimiter === null ) $delimiter = $this->output_delimiter;
		$data = $this->unparse($data, $fields, null, null, $delimiter);
		if ( $filename !== null ) {
			header('Content-type: application/csv');
			header('Content-Disposition: attachment; filename="'.$filename.'"');
			echo $data;
		}
		return $data;
	}
	
	/**
	 * Convert character encoding
	 * @param   input    input character encoding, uses default if left blank
	 * @param   output   output character encoding, uses default if left blank
	 * @return  nothing
	 */
	function encoding ($input = null, $output = null) {
		$this->convert_encoding = true;
		if ( $input !== null ) $this->input_encoding = $input;
		if ( $output !== null ) $this->output_encoding = $output;
	}
	
	/**
	 * Auto-Detect Delimiter: Find delimiter by analyzing a specific number of
	 * rows to determine most probable delimiter character
	 * @param   file           local CSV file
	 * @param   parse          true/false parse file directly
	 * @param   search_depth   number of rows to analyze
	 * @param   preferred      preferred delimiter characters
	 * @param   enclosure      enclosure character, default is double quote (").
	 * @return  delimiter character
	 */
	function auto ($file = null, $parse = true, $search_depth = null, $preferred = null, $enclosure = null) {
		
		if ( $file === null ) $file = $this->file;
		if ( empty($search_depth) ) $search_depth = $this->auto_depth;
		if ( $enclosure === null ) $enclosure = $this->enclosure;
		
		if ( $preferred === null ) $preferred = $this->auto_preferred;
		
		if ( empty($this->file_data) ) {
			if ( $this->_check_data($file) ) {
				$data = &$this->file_data;
			} else return false;
		} else {
			$data = &$this->file_data;
		}
		
		$chars = array();
		$strlen = strlen($data);
		$enclosed = false;
		$n = 1;
		$to_end = true;
		
		// walk specific depth finding posssible delimiter characters
		for ( $i=0; $i < $strlen; $i++ ) {
			$ch = $data{$i};
			$nch = ( isset($data{$i+1}) ) ? $data{$i+1} : false ;
			$pch = ( isset($data{$i-1}) ) ? $data{$i-1} : false ;
			
			// open and closing quotes
			if ( $ch == $enclosure ) {
				if ( !$enclosed || $nch != $enclosure ) {
					$enclosed = ( $enclosed ) ? false : true ;
				} elseif ( $enclosed ) {
					$i++;
				}
				
			// end of row
			} elseif ( ($ch == "\n" && $pch != "\r" || $ch == "\r") && !$enclosed ) {
				if ( $n >= $search_depth ) {
					$strlen = 0;
					$to_end = false;
				} else {
					$n++;
				}
				
			// count character
			} elseif (!$enclosed) {
				if ( !preg_match('/['.preg_quote($this->auto_non_chars, '/').']/i', $ch) ) {
					if ( !isset($chars[$ch][$n]) ) {
						$chars[$ch][$n] = 1;
					} else {
						$chars[$ch][$n]++;
					}
				}
			}
		}
		
		// filtering
		$depth = ( $to_end ) ? $n-1 : $n ;
		$filtered = array();
		foreach( $chars as $char => $value ) {
			if ( $match = $this->_check_count($char, $value, $depth, $preferred) ) {
				$filtered[$match] = $char;
			}
		}
		
		// capture most probable delimiter
		ksort($filtered);
		$this->delimiter = reset($filtered);
		
		// parse data
		if ( $parse ) $this->data = $this->parse_string();
		
		return $this->delimiter;
		
	}
	
	
	// ==============================================
	// ----- [ Core Functions ] ---------------------
	// ==============================================
	
	/**
	 * Read file to string and call parse_string()
	 * @param   file   local CSV file
	 * @return  2D array with CSV data, or false on failure
	 */
	function parse_file ($file = null) {
		if ( $file === null ) $file = $this->file;
		if ( empty($this->file_data) ) $this->load_data($file);
		return ( !empty($this->file_data) ) ? $this->parse_string() : false ;
	}
	
	/**
	 * Parse CSV strings to arrays
	 * @param   data   CSV string
	 * @return  2D array with CSV data, or false on failure
	 */
	function parse_string ($data = null) {
		if ( empty($data) ) {
			if ( $this->_check_data() ) {
				$data = &$this->file_data;
			} else return false;
		}
		
		$white_spaces = str_replace($this->delimiter, '', " \t\x0B\0");
		
		$rows = array();
		$row = array();
		$row_count = 0;
		$current = '';
		$head = ( !empty($this->fields) ) ? $this->fields : array() ;
		$col = 0;
		$enclosed = false;
		$was_enclosed = false;
		$strlen = strlen($data);
		
		// walk through each character
		for ( $i=0; $i < $strlen; $i++ ) {
			$ch = $data{$i};
			$nch = ( isset($data{$i+1}) ) ? $data{$i+1} : false ;
			$pch = ( isset($data{$i-1}) ) ? $data{$i-1} : false ;
			
			// open/close quotes, and inline quotes
			if ( $ch == $this->enclosure ) {
				if ( !$enclosed ) {
					if ( ltrim($current, $white_spaces) == '' ) {
						$enclosed = true;
						$was_enclosed = true;
					} else {
						$this->error = 2;
						$error_row = count($rows) + 1;
						$error_col = $col + 1;
						if ( !isset($this->error_info[$error_row.'-'.$error_col]) ) {
							$this->error_info[$error_row.'-'.$error_col] = array(
								'type' => 2,
								'info' => 'Syntax error found on row '.$error_row.'. Non-enclosed fields can not contain double-quotes.',
								'row' => $error_row,
								'field' => $error_col,
								'field_name' => (!empty($head[$col])) ? $head[$col] : null,
							);
						}
						$current .= $ch;
					}
				} elseif ($nch == $this->enclosure) {
					$current .= $ch;
					$i++;
				} elseif ( $nch != $this->delimiter && $nch != "\r" && $nch != "\n" ) {
					for ( $x=($i+1); isset($data{$x}) && ltrim($data{$x}, $white_spaces) == ''; $x++ ) {}
					if ( $data{$x} == $this->delimiter ) {
						$enclosed = false;
						$i = $x;
					} else {
						if ( $this->error < 1 ) {
							$this->error = 1;
						}
						$error_row = count($rows) + 1;
						$error_col = $col + 1;
						if ( !isset($this->error_info[$error_row.'-'.$error_col]) ) {
							$this->error_info[$error_row.'-'.$error_col] = array(
								'type' => 1,
								'info' =>
									'Syntax error found on row '.(count($rows) + 1).'. '.
									'A single double-quote was found within an enclosed string. '.
									'Enclosed double-quotes must be escaped with a second double-quote.',
								'row' => count($rows) + 1,
								'field' => $col + 1,
								'field_name' => (!empty($head[$col])) ? $head[$col] : null,
							);
						}
						$current .= $ch;
						$enclosed = false;
					}
				} else {
					$enclosed = false;
				}
				
			// end of field/row
			} elseif ( ($ch == $this->delimiter || $ch == "\n" || $ch == "\r") && !$enclosed ) {
				$key = ( !empty($head[$col]) ) ? $head[$col] : $col ;
				$row[$key] = ( $was_enclosed ) ? $current : trim($current) ;
				$current = '';
				$was_enclosed = false;
				$col++;
				
				// end of row
				if ( $ch == "\n" || $ch == "\r" ) {
					if ( $this->_validate_offset($row_count) && $this->_validate_row_conditions($row, $this->conditions) ) {
						if ( $this->heading && empty($head) ) {
							$head = $row;
						} elseif ( empty($this->fields) || (!empty($this->fields) && (($this->heading && $row_count > 0) || !$this->heading)) ) {
							if ( !empty($this->sort_by) && !empty($row[$this->sort_by]) ) {
								if ( isset($rows[$row[$this->sort_by]]) ) {
									$rows[$row[$this->sort_by].'_0'] = &$rows[$row[$this->sort_by]];
									unset($rows[$row[$this->sort_by]]);
									for ( $sn=1; isset($rows[$row[$this->sort_by].'_'.$sn]); $sn++ ) {}
									$rows[$row[$this->sort_by].'_'.$sn] = $row;
								} else $rows[$row[$this->sort_by]] = $row;
							} else $rows[] = $row;
						}
					}
					$row = array();
					$col = 0;
					$row_count++;
					if ( $this->sort_by === null && $this->limit !== null && count($rows) == $this->limit ) {
						$i = $strlen;
					}
					if ( $ch == "\r" && $nch == "\n" ) $i++;
				}
				
			// append character to current field
			} else {
				$current .= $ch;
			}
		}
		$this->titles = $head;
		if ( !empty($this->sort_by) ) {
			$sort_type = SORT_REGULAR;
			if ( $this->sort_type == 'numeric' ) {
				$sort_type = SORT_NUMERIC;
			} elseif ( $this->sort_type == 'string' ) {
				$sort_type = SORT_STRING;
			}
			( $this->sort_reverse ) ? krsort($rows, $sort_type) : ksort($rows, $sort_type) ;
			if ( $this->offset !== null || $this->limit !== null ) {
				$rows = array_slice($rows, ($this->offset === null ? 0 : $this->offset) , $this->limit, true);
			}
		}
		if ( !$this->keep_file_data ) {
			$this->file_data = null;
		}
		return $rows;
	}
	
	/**
	 * Create CSV data from array
	 * @param   data        2D array with data
	 * @param   fields      field names
	 * @param   append      if true, field names will not be output
	 * @param   is_php      if a php die() call should be put on the first
	 *                      line of the file, this is later ignored when read.
	 * @param   delimiter   field delimiter to use
	 * @return  CSV data (text string)
	 */
	function unparse ( $data = array(), $fields = array(), $append = false , $is_php = false, $delimiter = null) {
		if ( !is_array($data) || empty($data) ) $data = &$this->data;
		if ( !is_array($fields) || empty($fields) ) $fields = &$this->titles;
		if ( $delimiter === null ) $delimiter = $this->delimiter;
		
		$string = ( $is_php ) ? "<?php header('Status: 403'); die(' '); ?>".$this->linefeed : '' ;
		$entry = array();
		
		// create heading
		if ( $this->heading && !$append && !empty($fields) ) {
			foreach( $fields as $key => $value ) {
				$entry[] = $this->_enclose_value($value);
			}
			$string .= implode($delimiter, $entry).$this->linefeed;
			$entry = array();
		}
		
		// create data
		foreach( $data as $key => $row ) {
			foreach( $row as $field => $value ) {
				$entry[] = $this->_enclose_value($value);
			}
			$string .= implode($delimiter, $entry).$this->linefeed;
			$entry = array();
		}
		
		return $string;
	}
	
	/**
	 * Load local file or string
	 * @param   input   local CSV file
	 * @return  true or false
	 */
	function load_data ($input = null) {
		$data = null;
		$file = null;
		if ( $input === null ) {
			$file = $this->file;
		} elseif ( file_exists($input) ) {
			$file = $input;
		} else {
			$data = $input;
		}
		if ( !empty($data) || $data = $this->_rfile($file) ) {
			if ( $this->file != $file ) $this->file = $file;
			if ( preg_match('/\.php$/i', $file) && preg_match('/<\?.*?\?>(.*)/ims', $data, $strip) ) {
				$data = ltrim($strip[1]);
			}
			if ( $this->convert_encoding ) $data = iconv($this->input_encoding, $this->output_encoding, $data);
			if ( substr($data, -1) != "\n" ) $data .= "\n";
			$this->file_data = &$data;
			return true;
		}
		return false;
	}
	
	
	// ==============================================
	// ----- [ Internal Functions ] -----------------
	// ==============================================
	
	/**
	 * Validate a row against specified conditions
	 * @param   row          array with values from a row
	 * @param   conditions   specified conditions that the row must match 
	 * @return  true of false
	 */
	function _validate_row_conditions ($row = array(), $conditions = null) {
		if ( !empty($row) ) {
			if ( !empty($conditions) ) {
				$conditions = (strpos($conditions, ' OR ') !== false) ? explode(' OR ', $conditions) : array($conditions) ;
				$or = '';
				foreach( $conditions as $key => $value ) {
					if ( strpos($value, ' AND ') !== false ) {
						$value = explode(' AND ', $value);
						$and = '';
						foreach( $value as $k => $v ) {
							$and .= $this->_validate_row_condition($row, $v);
						}
						$or .= (strpos($and, '0') !== false) ? '0' : '1' ;
					} else {
						$or .= $this->_validate_row_condition($row, $value);
					}
				}
				return (strpos($or, '1') !== false) ? true : false ;
			}
			return true;
		}
		return false;
	}
	
	/**
	 * Validate a row against a single condition
	 * @param   row          array with values from a row
	 * @param   condition   specified condition that the row must match 
	 * @return  true of false
	 */
	function _validate_row_condition ($row, $condition) {
		$operators = array(
			'=', 'equals', 'is',
			'!=', 'is not',
			'<', 'is less than',
			'>', 'is greater than',
			'<=', 'is less than or equals',
			'>=', 'is greater than or equals',
			'contains',
			'does not contain',
		);
		$operators_regex = array();
		foreach( $operators as $value ) {
			$operators_regex[] = preg_quote($value, '/');
		}
		$operators_regex = implode('|', $operators_regex);
		if ( preg_match('/^(.+) ('.$operators_regex.') (.+)$/i', trim($condition), $capture) ) {
			$field = $capture[1];
			$op = $capture[2];
			$value = $capture[3];
			if ( preg_match('/^([\'\"]{1})(.*)([\'\"]{1})$/i', $value, $capture) ) {
				if ( $capture[1] == $capture[3] ) {
					$value = $capture[2];
					$value = str_replace("\\n", "\n", $value);
					$value = str_replace("\\r", "\r", $value);
					$value = str_replace("\\t", "\t", $value);
					$value = stripslashes($value);
				}
			}
			if ( array_key_exists($field, $row) ) {
				if ( ($op == '=' || $op == 'equals' || $op == 'is') && $row[$field] == $value ) {
					return '1';
				} elseif ( ($op == '!=' || $op == 'is not') && $row[$field] != $value ) {
					return '1';
				} elseif ( ($op == '<' || $op == 'is less than' ) && $row[$field] < $value ) {
					return '1';
				} elseif ( ($op == '>' || $op == 'is greater than') && $row[$field] > $value ) {
					return '1';
				} elseif ( ($op == '<=' || $op == 'is less than or equals' ) && $row[$field] <= $value ) {
					return '1';
				} elseif ( ($op == '>=' || $op == 'is greater than or equals') && $row[$field] >= $value ) {
					return '1';
				} elseif ( $op == 'contains' && preg_match('/'.preg_quote($value, '/').'/i', $row[$field]) ) {
					return '1';
				} elseif ( $op == 'does not contain' && !preg_match('/'.preg_quote($value, '/').'/i', $row[$field]) ) {
					return '1';
				} else {
					return '0';
				}
			}
		}
		return '1';
	}
	
	/**
	 * Validates if the row is within the offset or not if sorting is disabled
	 * @param   current_row   the current row number being processed
	 * @return  true of false
	 */
	function _validate_offset ($current_row) {
		if ( $this->sort_by === null && $this->offset !== null && $current_row < $this->offset ) return false;
		return true;
	}
	
	/**
	 * Enclose values if needed
	 *  - only used by unparse()
	 * @param   value   string to process
	 * @return  Processed value
	 */
	function _enclose_value ($value = null) {
		if ( $value !== null && $value != '' ) {
			$delimiter = preg_quote($this->delimiter, '/');
			$enclosure = preg_quote($this->enclosure, '/');
			if ( preg_match("/".$delimiter."|".$enclosure."|\n|\r/i", $value) || ($value{0} == ' ' || substr($value, -1) == ' ') ) {
				$value = str_replace($this->enclosure, $this->enclosure.$this->enclosure, $value);
				$value = $this->enclosure.$value.$this->enclosure;
			}
		}
		return $value;
	}
	
	/**
	 * Check file data
	 * @param   file   local filename
	 * @return  true or false
	 */
	function _check_data ($file = null) {
		if ( empty($this->file_data) ) {
			if ( $file === null ) $file = $this->file;
			return $this->load_data($file);
		}
		return true;
	}
	
	
	/**
	 * Check if passed info might be delimiter
	 *  - only used by find_delimiter()
	 * @return  special string used for delimiter selection, or false
	 */
	function _check_count ($char, $array, $depth, $preferred) {
		if ( $depth == count($array) ) {
			$first = null;
			$equal = null;
			$almost = false;
			foreach( $array as $key => $value ) {
				if ( $first == null ) {
					$first = $value;
				} elseif ( $value == $first && $equal !== false) {
					$equal = true;
				} elseif ( $value == $first+1 && $equal !== false ) {
					$equal = true;
					$almost = true;
				} else {
					$equal = false;
				}
			}
			if ( $equal ) {
				$match = ( $almost ) ? 2 : 1 ;
				$pref = strpos($preferred, $char);
				$pref = ( $pref !== false ) ? str_pad($pref, 3, '0', STR_PAD_LEFT) : '999' ;
				return $pref.$match.'.'.(99999 - str_pad($first, 5, '0', STR_PAD_LEFT));
			} else return false;
		}
	}
	
	/**
	 * Read local file
	 * @param   file   local filename
	 * @return  Data from file, or false on failure
	 */
	function _rfile ($file = null) {
		if ( is_readable($file) ) {
			if ( !($fh = fopen($file, 'r')) ) return false;
			$data = fread($fh, filesize($file));
			fclose($fh);
			return $data;
		}
		return false;
	}

	/**
	 * Write to local file
	 * @param   file     local filename
	 * @param   string   data to write to file
	 * @param   mode     fopen() mode
	 * @param   lock     flock() mode
	 * @return  true or false
	 */
	function _wfile ($file, $string = '', $mode = 'wb', $lock = 2) {
		if ( $fp = fopen($file, $mode) ) {
			flock($fp, $lock);
			$re = fwrite($fp, $string);
			$re2 = fclose($fp);
			if ( $re != false && $re2 != false ) return true;
		}
		return false;
	}
	
}

?>