<?php
/**
 * \file
 * \brief Response to Verb ListRecords
 *
 * Lists records according to conditions. If there are too many, a resumptionToken is generated.
 * - If a request comes with a resumptionToken and is still valid, read it and send back records.
 * - Otherwise, set up a query with conditions such as: 'metadataPrefix', 'from', 'until', 'set'.
 * Only 'metadataPrefix' is compulsory.  All conditions are accessible through global array variable <B>$args</B>  by keywords.
 */

debug_message("\nI am debuging". __FILE__) ;

// Resume previous session?
if (isset($args['resumptionToken'])) {
    if (!file_exists(TOKEN_PREFIX.$args['resumptionToken'])) {
        $errors[] = oai_error('badResumptionToken', '', $args['resumptionToken']);
    } else {
        $readings = readResumToken(TOKEN_PREFIX.$args['resumptionToken']);
        if ($readings == false) {
            $errors[] = oai_error('badResumptionToken', '', $args['resumptionToken']);
        } else {
            debug_var_dump('readings',$readings);
            list($deliveredrecords, $extquery, $metadataPrefix) = $readings;
        }
    }
} else { // no, we start a new session
    $deliveredrecords = 0;
    $extquery = '';

    $metadataPrefix = $args['metadataPrefix'];

    if (isset($args['from'])) {
        $from = checkDateFormat($args['from']);
        $extquery .= fromQuery($from);
    }

    if (isset($args['until'])) {
        $until = checkDateFormat($args['until']);
        $extquery .= untilQuery($until);
    }

    if (isset($args['set'])) {
        if (is_array($SETS)) {
            $extquery .= setQuery($args['set']);
        } else {
            $errors[] = oai_error('noSetHierarchy');
        }
    }
}

if (!empty($errors)) {
    oai_exit();
}

// Load the handler
if (is_array($METADATAFORMATS[$metadataPrefix]) && isset($METADATAFORMATS[$metadataPrefix]['myhandler'])) {
    $inc_record  = $METADATAFORMATS[$metadataPrefix]['myhandler'];
    include($inc_record);
} else {
    $errors[] = oai_error('cannotDisseminateFormat', 'metadataPrefix', $metadataPrefix);
}

if (!empty($errors)) {
    oai_exit();
}

if (empty($errors)) {
    $query = selectallQuery($metadataPrefix) . $extquery;
    debug_message("Query: $query") ;

    $res = $db->prepare($query, array(PDO::ATTR_CURSOR => PDO::CURSOR_SCROLL));
    $r = $res->execute();
    if (($r===false) ) {
        if ( (SHOW_QUERY_ERROR)) {
            echo __FILE__.','.__LINE__."<br />";
            echo "Query: $query<br />\n";
            print_r($db->errorInfo());
            exit();
        } else {
            $errors[] = oai_error('noRecordsMatch');
        }		
    } else {
        $r = $res->setFetchMode(PDO::FETCH_ASSOC);
        if ($r===false) {
            exit("FetchMode is not supported");
        }
        $num_rows = rowCount($metadataPrefix, $extquery, $db);
        if ($num_rows==0) {
            if (SHOW_QUERY_ERROR) {
                echo "Cannot find records: $query\n";
            }
            $errors[] = oai_error('noRecordsMatch');
        }
    }
}

if (!empty($errors)) {
    oai_exit();
}

// Will we need a new ResumptionToken?
if($args['verb']=='ListRecords') {
    $maxItems = MAXRECORDS;
} elseif($args['verb']=='ListIdentifiers') {
    $maxItems = MAXIDS;
} else {
    exit("Check ".__FILE__." ".__LINE__.", there is something wrong.");
}
$maxrec = min($num_rows - $deliveredrecords, $maxItems);

if ($num_rows - $deliveredrecords > $maxItems) {
    $cursor = (int)$deliveredrecords + $maxItems;
    $restoken = createResumToken($cursor, $extquery, $metadataPrefix);
    $expirationdatetime = gmstrftime('%Y-%m-%dT%TZ', time()+TOKEN_VALID);	
} elseif (isset($args['resumptionToken'])) {
// Last delivery, return empty ResumptionToken
    $restoken = $args['resumptionToken']; // just used as an indicator
    unset($expirationdatetime);
}

if (isset($args['resumptionToken'])) {
    debug_message("Try to resume because a resumptionToken supplied.") ;
    $record = $res->fetch(PDO::FETCH_ASSOC, PDO::FETCH_ORI_ABS, $deliveredrecords);
}
// Record counter
$countrec  = 0;

// Publish a batch to $maxrec number of records
$outputObj = new ANDS_Response_XML($args);
while ($countrec++ < $maxrec) {
    $record = $res->fetch(PDO::FETCH_ASSOC);
    if ($record===false) {
        if (SHOW_QUERY_ERROR) {
            echo __FILE__.",". __LINE__."<br />";
            print_r($db->errorInfo());
            exit();
        }
    }

    $identifier = $oaiprefix.$record[$SQL['identifier']];
    $datestamp = formatDatestamp($record[$SQL['datestamp']]);
    $setspec = $record[$SQL['set']];

    // debug_var_dump('record', $record);
    $status_deleted = (isset($record[$SQL['deleted']]) && ($record[$SQL['deleted']] === true) &&
                       ($deletedRecord == 'transient' || $deletedRecord == 'persistent'));

    //debug_var_dump('status_deleted', $status_deleted);
    if($args['verb']=='ListRecords') {
        $cur_record = $outputObj->create_record();
        $cur_header = $outputObj->create_header($identifier, $datestamp,$setspec,$cur_record);
        // return the metadata record itself
        if (!$status_deleted) {
            debug_var_dump('inc_record',$inc_record);
            create_metadata($outputObj, $cur_record, $identifier, $setspec, $db);
        }	
    } else { // for ListIdentifiers, only identifiers will be returned.
        $cur_header = $outputObj->create_header($identifier, $datestamp,$setspec);
    }
    if ($status_deleted) {
        $cur_header->setAttribute("status","deleted");
    }
}

// ResumptionToken
if (isset($restoken)) {
    if(isset($expirationdatetime)) {
        $outputObj->create_resumpToken($restoken,$expirationdatetime,$num_rows,$cursor);
    } else {
        $outputObj->create_resumpToken('',null,$num_rows,$deliveredrecords);
    }	
}

// end ListRecords
if (SHOW_QUERY_ERROR) {echo "Debug listrecord.php reached to the end.\n\n";}