<?php
/* vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4: */

/**
 * File::CSV
 *
 * PHP versions 4 and 5
 *
 * Copyright (c) 2002-2008,
 *  Tomas V.V.Cox <cox@idecnet.com>,
 *  Helgi Þormar Þorbjörnsson <helgi@php.net>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *     * Redistributions of source code must retain the above copyright notice,
 *       this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * @category    File
 * @package     File
 * @author      Tomas V.V.Cox <cox@idecnet.com>
 * @author      Helgi Þormar Þorbjörnsson <helgi@php.net>
 * @copyright   2004-2011 The Authors
 * @license     http://www.opensource.org/licenses/bsd-license.php New BSD License
 * @version     CVS: $Id$
 * @link        http://pear.php.net/package/File
 */

require_once 'PEAR.php';
require_once 'File.php';

/**
 * File class for handling CSV files (Comma Separated Values), a common format
 * for exchanging data.
 *
 * TODO:
 *  - Usage example and Doc
 *  - Use getPointer() in discoverFormat
 *  - Add a line counter for being able to output better error reports
 *  - Store the last error in GLOBALS and add File_CSV::getLastError()
 *
 * Wish:
 *  - Other methods like readAll(), writeAll(), numFields(), numRows()
 *  - Try to detect if a CSV has header or not in discoverFormat() (not possible with CSV)
 *
 * Known Bugs:
 * (they has been analyzed but for the moment the impact in the speed for
 *  properly handle this uncommon cases is too high and won't be supported)
 *  - A field which is composed only by a single quoted separator (ie -> ;";";)
 *    is not handled properly
 *  - When there is exactly one field minus than the expected number and there
 *    is a field with a separator inside, the parser will throw the "wrong count" error
 *
 * Info about CSV and links to other sources
 * http://rfc.net/rfc4180.html
 *
 * @author Tomas V.V.Cox <cox@idecnet.com>
 * @author Helgi Þormar Þorbjörnsson <helgi@php.net>
 * @package File
 * @license http://www.opensource.org/licenses/bsd-license.php New BSD License
 */
class File_CSV
{
    /**
    * This raiseError method works in a different way. It will always return
    * false (an error occurred) but it will call PEAR::raiseError() before
    * it. If no default PEAR global handler is set, will trigger an error.
    *
    * @param string $error The error message
    * @return bool always false
    */
    static function raiseError($error)
    {
        // If a default PEAR Error handler is not set trigger the error
        // XXX Add a PEAR::isSetHandler() method?
        if ($GLOBALS['_PEAR_default_error_mode'] == PEAR_ERROR_RETURN) {
            PEAR::raiseError($error, null, PEAR_ERROR_TRIGGER, E_USER_WARNING);
        } else {
            PEAR::raiseError($error);
        }
        return false;
    }

    /**
    * Checks the configuration given by the user
    *
    * @access private
    * @param string &$error The error will be written here if any
    * @param array  &$conf  The configuration assoc array
    * @return string error    Returns a error message
    */
    static function _conf(&$error, &$conf)
    {
        // check conf
        if (!is_array($conf)) {
            return $error = 'Invalid configuration';
        }

        if (!isset($conf['fields']) || !(int)$conf['fields']) {
            return $error = 'The number of fields must be numeric (the "fields" key)';
        }

        if (isset($conf['sep'])) {
            if (strlen($conf['sep']) !== 1) {
                return $error = 'Separator can only be one char';
            }
        } elseif ($conf['fields'] > 1) {
            return $error = 'Missing separator (the "sep" key)';
        } else {
            // to avoid undefined index notices
            $conf['sep'] = ',';
        }

        if (isset($conf['quote'])) {
            if (strlen($conf['quote']) !== 1) {
                return $error = 'The quote char must be one char (the "quote" key)';
            }
        } else {
            $conf['quote'] = '"';
        }

        if (!isset($conf['crlf'])) {
            $conf['crlf'] = "\n";
        }

        if (!isset($conf['eol2unix'])) {
            $conf['eol2unix'] = true;
        }
    }

    /**
    * Return or create the file descriptor associated with a file
    *
    * @param string $file The name of the file
    * @param array  &$conf The configuration
    * @param string $mode The open node (ex: FILE_MODE_READ or FILE_MODE_WRITE)
    * @param boolean $reset if passed as true and resource for the file exists
    *                       than the file pointer will be moved to the beginning
    *
    * @return mixed A file resource or false
    */
    static function getPointer($file, &$conf, $mode = FILE_MODE_READ, $reset = false)
    {
        static $resources = array();
        if (isset($resources[$file][$mode])) {
            if ($reset) {
                fseek($resources[$file][$mode], 0);
            }

            return $resources[$file][$mode];
        }

        File_CSV::_conf($error, $conf);
        if ($error) {
            return File_CSV::raiseError($error);
        }

        PEAR::pushErrorHandling(PEAR_ERROR_RETURN);
        $fp = File::_getFilePointer($file, $mode);
        PEAR::popErrorHandling();
        if (PEAR::isError($fp)) {
            return File_CSV::raiseError($fp);
        }

        $resources[$file][$mode] = $fp;
        return $fp;
    }

    /**
     * Unquote data
     *
     * @param array|string $data The data to unquote
     * @param string $quote The quote char
     * @return string the unquoted data
     */
    static function unquote($data, $quote)
    {
        $isString = false;
        if (!is_array($data)) {
            $data = array($data);
            $isString = true;
        }

        // Get rid of escaped quotes
        $data = str_replace($quote.$quote, $quote, $data);

        $tmp = array();
        foreach ($data as $key => $field) {
            // Trim first the string.
            $field = trim($field);

            // Incase null fields (form: ;;)
            $field_len = strlen($field);
            if (!$field_len) {
                if ($isString) {
                    return $field;
                }
                $tmp[$key] = $field;
                continue;
            }

            // excel compat
            if ($field[0] === '=' && $field[1] === '"') {
                $field = str_replace('="', '"', $field);
                --$field_len;
            }

            if ($field[0] === $quote && $field[$field_len - 1] === $quote) {
                // Get rid of quotes around the field
                $field = substr($field, 1, -1);
            }

            if ($isString) {
                $tmp = $field;
            } else {
                $tmp[$key] = $field;
            }
        }

        return $tmp;
    }

    /**
    * Reads a row of data as an array from a CSV file. It's able to
    * read memo fields with multiline data.
    *
    * @param string $file   The filename where to write the data
    * @param array  &$conf   The configuration of the dest CSV
    *
    * @return mixed Array with the data read or false on error/no more data
    */
    static function readQuoted($file, &$conf)
    {
        if (!$fp = File_CSV::getPointer($file, $conf, FILE_MODE_READ)) {
            return false;
        }

        $buff = $old = $prev = $c = '';
        $ret    = array();
        $fields = 1;
        $in_quote = false;
        $quote    = $conf['quote'];
        $f        = (int)$conf['fields'];
        $sep      = $conf['sep'];
        while (false !== $ch = fgetc($fp)) {
            $old  = $prev;
            $prev = $c;
            $c    = $ch;

            // Common case
            if ($c != $quote && $c != $sep && $c != "\n" && $c != "\r") {
                $buff .= $c;
                continue;
            }

            // Start quote.
            if (
                $in_quote === false &&
                $quote && $c == $quote &&
                (
                 $prev == $sep || $prev == "\n" || $prev === null ||
                 $prev == "\r" || $prev == '' || $prev == ' '
                 || $prev == '=' //excel compat
                )
            ) {
                $in_quote = true;
                // excel compat, removing the = part but only if we are in a quote
                if ($prev == '=') {
                    $buff = substr($buff, 0, -1);
                }
            }

            if ($in_quote) {
                // When does the quote end, make sure it's not double quoted
                if ($c == $sep && $prev == $quote && $old != $quote) {
                    $in_quote = false;
                } elseif ($c == $sep && $buff == $quote.$quote) {
                    // In case we are dealing with double quote but empty value
                    $in_quote = false;
                } elseif ($c == "\n" || $c == "\r") {
                    $sub = ($prev == "\r") ? 2 : 1;
                    $buff_len = strlen($buff);
                    if (
                        $buff_len >= $sub &&
                        $buff[$buff_len - $sub] == $quote
                    ) {
                        $in_quote = false;
                    }
                }
            }

            if (!$in_quote && ($c == $sep || $c == "\n" || $c == "\r")) {
                $return = File_CSV::_readQuotedFillers($fp, $f, $fields, $ret,
                                                       $buff, $quote, $c, $sep);
                if ($return !== false) {
                    return $return;
                }

                if ($prev == "\r") {
                    $buff = substr($buff, 0, -1);
                }

                // Convert EOL character to Unix EOL (LF).
                if ($conf['eol2unix']) {
                    $buff = preg_replace('/(\r\n|\r)$/', "\n", $buff);
                    // Below replaces things everywhere not just EOL
                    //$buff = str_replace(array("\r\n", "\r"), "\n", $buff);
                }

                $ret[] = File_CSV::unquote($buff, $quote);
                if (count($ret) === $f) {
                    return $ret;
                }
                $buff = '';
                ++$fields;
                continue;
            }

            $buff .= $c;
        }

        /* If it's the end of the file and we still have something in buffer
         * then we process it since files can have no CL/FR at the end
         */
        $feof = feof($fp);
        if ($feof && strlen($buff) > 0 && !in_array($buff, array("\r", "\n"))) {
            $ret[] = File_CSV::unquote($buff, $quote);
            if (count($ret) == $f) {
                return $ret;
            }
        }

        if ($feof && count($ret) !== $f) {
            $return = File_CSV::_readQuotedFillers($fp, $f, $fields, $ret,
                                                   $buff, $quote, $c, $sep);
            if ($return !== false) {
                return $return;
            }
        }

        return !$feof ? $ret : false;
    }

    /**
     * Adds missing fields (empty ones)
     *
     * @param resource $fp the file resource
     * @param string   $f
     * @param integer  $fields the field count
     * @param array    $ret    the processed fields in a array
     * @param string   $buff   the buffer before it gets put through unquote
     * @param string   $quote  Quote in use
     * @param string   $c      the char currently being worked with
     * @param string   $sep    Separator in use
     *
     * @access private
     * @return array | boolean returns false if no data should return out.
     */
    static function _readQuotedFillers($fp, $f, $fields, $ret, $buff, $quote, &$c, $sep)
    {
        // More fields than expected
        if ($c == $sep && (count($ret) + 1) === $f) {
            // Seek the pointer into linebreak character.
            while (true) {
                $c = fgetc($fp);
                if  ($c == "\n" || $c == "\r" || $c == '') {
                    break;
                }
            }

            // Insert last field value.
            $ret[] = File_CSV::unquote($buff, $quote);
            return $ret;
        }

        // Less fields than expected
        if (($c == "\n" || $c == "\r") && $fields !== $f) {
            // Insert last field value.
            $ret[] = File_CSV::unquote($buff, $quote);
            if (count($ret) === 1 && empty($ret[0])) {
                return array();
            }

            // Pair the array elements to fields count. - inserting empty values
            $ret_count = count($ret);
            $sum = ($f - 1) - ($ret_count - 1);
            $data = array_merge($ret, array_fill($ret_count, $sum, ''));
            return $data;
        }

        return false;
    }

    /**
    * Reads a "row" from a CSV file and return it as an array
    *
    * @param string $file The CSV file
    * @param array  &$conf The configuration of the dest CSV
    *
    * @return mixed Array or false
    */
    static function read($file, &$conf)
    {
        if (!$fp = File_CSV::getPointer($file, $conf, FILE_MODE_READ)) {
            return false;
        }

        // The size is limited to 4K
        if (!$line = fgets($fp, 4096)) {
            return false;
        }

        if ($conf['fields'] === 1) {
            $fields      = array($line);
            $field_count = 1;
        } else {
            $fields      = explode($conf['sep'], $line);
            $field_count = count($fields);
        }

        $real_field_count = $field_count - 1;
        $check_char = $fields[$real_field_count];
        if ($check_char === "\n" || $check_char === "\r") {
            array_pop($fields);
            --$field_count;
        }

        $last =& $fields[$real_field_count];
        if (
            $field_count !== $conf['fields'] || $conf['quote']
            && (
                !is_null($last) && $last !== ''
                && (
                    ($last[0] === $conf['quote'] && $last[strlen(rtrim($last)) - 1] !== $conf['quote'])
                    // excel support
                    || ($last[0] === '=' && $last[1] === $conf['quote'])
                    // if the row has spaces or other extra chars before the quote
                    //|| preg_match('|^\s+\\' . $conf['quote'] .'|', $last)
                )
            )
            // XXX perhaps there is a separator inside a quoted field
            // || preg_match("|{$conf['quote']}.*{$conf['sep']}.*{$conf['quote']}|", $line)
            // The regex above is really slow
             || ((count(explode(',', $line))) > $field_count)
        ) {
            fseek($fp, -1 * strlen($line), SEEK_CUR);
            $fields = File_CSV::readQuoted($file, $conf);
            $fields = File_CSV::_processHeaders($fields, $conf);
            return $fields;
        }

        $fields = File_CSV::unquote($fields, $conf['quote']);

        if ($field_count != $conf['fields']) {
            File_CSV::raiseError("Read wrong fields number count: '". $field_count .
                                  "' expected ".$conf['fields']);
            return true;
        }

        $fields = File_CSV::_processHeaders($fields, $conf);
        return $fields;
    }

    /**
     * Process the field array being passed in and map the array over to
     * the header values if the configuration is set on.
     *
     * @param array $fields The CSV row columns
     * @param array $conf File_CSV configuration
     *
     * @return array Processed array
     */
    static function _processHeaders($fields, &$conf)
    {
        static $headers = array();

        if (isset($conf['header']) && $conf['header'] == true && empty($headers)) {
            // read the first row and assign to $headers
            $headers = $fields;
            return $headers;
        }

        if (!empty($headers)) {
            $tmp = array();
            foreach ($fields as $k => $v) {
                if (isset($headers[$k])) {
                    $tmp[$headers[$k]] = $v;
                }
            }
            $fields = $tmp;
        }

        return $fields;
    }

    /**
    * Internal use only, will be removed in the future
    *
    * @param string $str The string to debug
    * @access private
    */
    static function _dbgBuff($str)
    {
        if (strpos($str, "\r") !== false) {
            $str = str_replace("\r", "_r_", $str);
        }
        if (strpos($str, "\n") !== false) {
            $str = str_replace("\n", "_n_", $str);
        }
        if (strpos($str, "\t") !== false) {
            $str = str_replace("\t", "_t_", $str);
        }
        if ($str === null) {
            $str = '_NULL_';
        }
        if ($str === '') {
            $str = 'Empty string';
        }
        echo "buff: ($str)\n";
    }

    /**
    * Writes a struc (array) in a file as CSV
    *
    * @param string $file   The filename where to write the data
    * @param array  $fields Ordered array with the data
    * @param array  &$conf   The configuration of the dest CSV
    *
    * @return bool True on success false otherwise
    */
    static function write($file, $fields, &$conf)
    {
        if (!$fp = File_CSV::getPointer($file, $conf, FILE_MODE_WRITE)) {
            return false;
        }

        $field_count = count($fields);
        if ($field_count != $conf['fields']) {
            File_CSV::raiseError("Wrong fields number count: '". $field_count .
                                  "' expected ".$conf['fields']);
            return true;
        }

        $write = '';
        $quote = $conf['quote'];
        for ($i = 0; $i < $field_count; ++$i) {
            // Write a single field

            $quote_field = false;
            // Only quote this field in the following cases:
            if (is_numeric($fields[$i])) {
                // Numeric fields should not be quoted
            } elseif (isset($conf['sep']) && (strpos($fields[$i], $conf['sep']) !== false)) {
                // Separator is present in field
                $quote_field = true;
            } elseif (strpos($fields[$i], $quote) !== false) {
                // Quote character is present in field
                $quote_field = true;
            } elseif (
                   strpos($fields[$i], "\n") !== false
                || strpos($fields[$i], "\r") !== false
            ) {
                // Newline is present in field
                $quote_field = true;
            } elseif (!is_numeric($fields[$i]) && (substr($fields[$i], 0, 1) == " " || substr($fields[$i], -1) == " ")) {
                // Space found at beginning or end of field value
                $quote_field = true;
            }

            if ($quote_field) {
                // Escape the quote character within the field (e.g. " becomes "")
                $quoted_value = str_replace($quote, $quote.$quote, $fields[$i]);

                $write .= $quote . $quoted_value . $quote;
            } else {
                $write .= $fields[$i];
            }

            $write .= ($i < ($field_count - 1)) ? $conf['sep']: $conf['crlf'];
        }

        if (!fwrite($fp, $write, strlen($write))) {
            return File_CSV::raiseError('Can not write to file');
        }

        return true;
    }

    /**
    * Discover the format of a CSV file (the number of fields, the separator
    * and if it quote string fields)
    *
    * @param string the CSV file name
    * @param array extra separators that should be checked for.
    * @return mixed Assoc array or false
    */
    static function discoverFormat($file, $extraSeps = array())
    {
        if (!$fp = @fopen($file, 'rb')) {
            return File_CSV::raiseError("Could not open file: $file");
        }

        // Set auto detect line ending for Mac EOL support
        $oldini = ini_get('auto_detect_line_endings');
        if ($oldini != '1') {
            ini_set('auto_detect_line_endings', '1');
        }

        // Take the first 30 lines and store the number of occurrences
        // for each separator in each line
        $lines = '';
        for ($i = 0; $i < 30 && !feof($fp) && $line = fgets($fp, 4096); $i++) {
            $lines .= $line;
        }
        fclose($fp);

        if ($oldini != '1') {
            ini_set('auto_detect_line_endings', $oldini);
        }

        $seps = array("\t", ';', ':', ',');
        $seps = array_merge($seps, $extraSeps);
        $matches = array();
        $quotes = '"\'';

        while ($lines != ($newLines = preg_replace('|((["\'])[^"]*(\2))|', '\2_\2', $lines))) {
            $lines = $newLines;
        }

        $eol   = strpos($lines, "\r") ? "\r" : "\n";
        $lines = explode($eol, $lines);
        foreach ($lines as $line) {
            $orgLine = $line;
            foreach ($seps as $sep) {
                $line = preg_replace("|^[$quotes$sep]*$sep*([$quotes][^$quotes]*[$quotes])|sm", '_', $orgLine);
                // Find all seps that are within qoutes
                ///FIXME ... counts legitimit lines as bad ones

                 // In case there's a whitespace infront the field
                $regex = '|\s*?';
                 // Match the first quote (optional), also optionally match = since it's excel stuff
                $regex.= "(?:\=?[$quotes])";
                $regex.= '(.*';
                // Don't match a sep if we are inside a quote
                // also don't accept the sep if it has a quote on the either side
                ///FIXME has to be possible if we are inside a quote! (tests fail because of this)
                $regex.= "(?:[^$quotes])$sep(?:[^$quotes])";
                $regex.= '.*)';
                // Close quote (if it's present) and the sep (optional, could be end of line)
                $regex.= "(?:[$quotes](?:$sep?))|Ums";

                preg_match_all($regex, $line, $match);
                // Finding all seps, within quotes or not
                $sep_count = substr_count($line, $sep);
                // Real count
                $matches[$sep][] = $sep_count - count($match[0]);
            }
        }

        $final = array();
        // Group the results by amount of equal ocurrences
        foreach ($matches as $sep => $res) {
            // Use max fields count.
            $fields[$sep] = $res[0];
            $amount[$sep] = array_sum($res);
        }

        arsort($amount);
        $sep = array_sum(array_values($amount)) == 0 ? array_key_last($amount) : key($amount);

        $conf['fields'] = $fields[$sep] + 1;
        $conf['sep']    = $sep;

        // Test if there are fields with quotes around in the first 30 lines
        $quote  = null;

        $string = implode('', $lines);
        foreach (array('"', '\'') as $q) {
            if (preg_match_all("|$sep(?:\s*?)(\=?[$q]).*([$q])$sep?|Us", $string, $match)) {
                if ($match[1][0] == $match[2][0]) {
                    $quote = $match[1][0];
                    break;
                }
            }

            if (
                preg_match_all("|^(\=?[$q]).*([$q])$sep{0,1}|Ums", $string, $match)
                || preg_match_all("|(\=?[$q]).*([$q])$sep\s$|Ums", $string, $match)
            ) {
                if ($match[1][0] == $match[2][0]) {
                    $quote = $match[1][0];
                    break;
                }
            }
        }

        $conf['quote'] = $quote;
        return $conf;
    }

    /**
     * Front to call getPointer and moving the resource to the
     * beginning of the file
     * Reset it if you like.
     *
     * @param string $file The name of the file
     * @param array  &$conf The configuration
     * @param string $mode The open node (ex: FILE_MODE_READ or FILE_MODE_WRITE)
     *
     * @return boolean true on success false on failure
     */
    static function resetPointer($file, &$conf, $mode)
    {
        if (!File_CSV::getPointer($file, $conf, $mode, true)) {
            return false;
        }

        return true;
    }
}
