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*/

package com.google.refine.sorting;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;

import com.google.refine.browsing.RowVisitor;
import com.google.refine.model.Project;
import com.google.refine.model.Row;
import com.google.refine.sorting.Criterion.KeyMaker;

public class SortingRowVisitor extends BaseSorter implements RowVisitor {
    final protected RowVisitor _visitor;
    protected List<IndexedRow> _indexedRows;

    static protected class IndexedRow {
        final int index;
        final Row row;

        IndexedRow(int index, Row row) {
            this.index = index;
            this.row = row;
        }
    }

    public SortingRowVisitor(RowVisitor visitor) {
        _visitor = visitor;
    }

    @Override
    public void start(Project project) {
        int count = project.rows.size();
        _indexedRows = new ArrayList<IndexedRow>(count);
        _keys = new ArrayList<Object[]>(count);
    }

    @Override
    public void end(Project project) {
        _visitor.start(project);

        Collections.sort(_indexedRows, new Comparator<IndexedRow>() {
            Project project;

            Comparator<IndexedRow> init(Project project) {
                this.project = project;
                return this;
            }

            @Override
            public int compare(IndexedRow o1, IndexedRow o2) {
                return SortingRowVisitor.this.compare(project, o1.row, o1.index, o2.row, o2.index);
            }
        }.init(project));

        for (IndexedRow indexedRow : _indexedRows) {
            _visitor.visit(project, indexedRow.index, indexedRow.row);
        }

        _visitor.end(project);
    }

    @Override
    public boolean visit(Project project, int rowIndex, Row row) {
        _indexedRows.add(new IndexedRow(rowIndex, row));
        return false;
    }

    @Override
    protected Object makeKey(
            Project project, KeyMaker keyMaker, Criterion c, Object o, int index) {

        return keyMaker.makeKey(project, (Row) o, index);
    }
}