package com.megatim.fdxcommons.tools.database.queries;

import com.megatim.fdxcommons.tools.database.queries.metadata.QueryCriterion;
import com.megatim.fdxcommons.tools.database.contrat.DefaultPreparedStatementProcessor;
import com.megatim.fdxcommons.tools.database.contrat.QueryMetaData;
import com.megatim.fdxcommons.tools.database.queries.metadata.QueryParam;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.util.ArrayList;
import java.util.List;

/**
 *
 * @author Gabuntu
 */
public class UpdateQuery implements QueryMetaData<Void> {

    private final Connection connection;
    private final QueryCriterion queryCriterion;
    private final String tableName;
    private final List<String> columnNames;
    private final List<QueryParam> params;

    public UpdateQuery(Connection connection, QueryCriterion queryCriterion, String tableName, List<String> columnNames, List<QueryParam> params) {
        this.connection = connection;
        this.queryCriterion = queryCriterion;
        this.tableName = tableName;
        this.columnNames = columnNames;
        this.params = params;
    }

    @Override
    public Void execute() throws Exception {

        System.out.println("<----------------------------------------------------------------------------------------------------------->");
        System.out.println(updateQuery());
        System.out.println("<----------------------------------------------------------------------------------------------------------->");

        try ( PreparedStatement statement = connection.prepareStatement(updateQuery())) {
            new DefaultPreparedStatementProcessor().process(statement, params);
            statement.execute();
        }

        return null;
    }

    private String updateQuery() throws Exception {
        return "UPDATE " + tableName + " " + setQueryPart() + " " + new WhereQueryString(queryCriterion).query();
    }

    private String setQueryPart() throws Exception {

        List<String> columnsToUpdate = new ArrayList<>(columnNames);

        StringBuilder query = new StringBuilder("SET ");
        int index = 0;

        for (String column : columnsToUpdate) {
            if ((index + 1) < columnsToUpdate.size()) {
                query.append(column).append(" = ? ,");
            } else {
                query.append(column).append(" = ?");
            }
            index++;
        }
        return query.toString();
    }

}