/*
 * Copyright (c) 2013-2018, Centre for Genomic Regulation (CRG).
 * Copyright (c) 2013-2018, Paolo Di Tommaso and the respective authors.
 *
 *   This file is part of 'Nextflow'.
 *
 *   Nextflow is free software: you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation, either version 3 of the License, or
 *   (at your option) any later version.
 *
 *   Nextflow is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with Nextflow.  If not, see <http://www.gnu.org/licenses/>.
 */

package nextflow.util

import groovy.transform.CompileStatic

/**
 *
 * @author Paolo Di Tommaso <paolo.ditommaso@gmail.com>
 */
@CompileStatic
class CollectionHelper {


    static List flatten( Collection collection ) {
        def result = []
        flatten(collection, { result << it })
        return result
    }

    static void flatten( Collection list, Closure row ) {

        def maxLen = 1
        list.each { if( it instanceof Collection ) { maxLen = Math.max(maxLen,((Collection)it).size()) } }

        for( int i=0; i<maxLen; i++ ) {
            def set = new ArrayList(list.size())

            for( int j=0; j<list.size(); j++ ) {
                def val = list[j]
                if( val instanceof Collection )
                    set[j] = i < ((Collection)val).size() ? ((Collection)val)[i] : null
                else
                    set[j] = val
            }

            row.call(set)
        }


    }

}
