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

import com.megatim.fdxcommons.tools.database.queries.metadata.QueryCriterion;
import com.megatim.fdxcommons.model.enumeration.CriteriaLogicConnector;
import com.megatim.fdxcommons.model.enumeration.Operateur;
import static com.megatim.fdxcommons.model.enumeration.Operateur.BETWEEN;
import static com.megatim.fdxcommons.model.enumeration.Operateur.EQUALS;
import static com.megatim.fdxcommons.model.enumeration.Operateur.GREATER_OR_EQUALS_THAN;
import static com.megatim.fdxcommons.model.enumeration.Operateur.GREATER_THAN;
import static com.megatim.fdxcommons.model.enumeration.Operateur.IN;
import static com.megatim.fdxcommons.model.enumeration.Operateur.IS_NOT_NULL;
import static com.megatim.fdxcommons.model.enumeration.Operateur.IS_NULL;
import static com.megatim.fdxcommons.model.enumeration.Operateur.LIKE;
import static com.megatim.fdxcommons.model.enumeration.Operateur.LOWER_OR_EQUALS_THAN;
import static com.megatim.fdxcommons.model.enumeration.Operateur.LOWER_THAN;
import static com.megatim.fdxcommons.model.enumeration.Operateur.NOT_BETWEEN;
import static com.megatim.fdxcommons.model.enumeration.Operateur.NOT_EQUALS;
import static com.megatim.fdxcommons.model.enumeration.Operateur.NOT_IN;
import java.util.List;

/**
 *
 * @author Gabuntu
 */
public class WhereQueryString {

    private final QueryCriterion queryCriterion;

    public WhereQueryString(QueryCriterion queryCriterion) {
        this.queryCriterion = queryCriterion;
    }

    public String query() {
        StringBuilder query = new StringBuilder("");
        if (queryCriterion != null) {
            query
                    .append(" WHERE ")
                    .append(buildQuery(queryCriterion));
        }
        return query.toString();
    }

    private String buildQuery(QueryCriterion criterion) {
        StringBuilder query = new StringBuilder();

        if (criterion.getSubCriteria().isEmpty()) {

            switch (criterion.getOperateur()) {
                case EQUALS:
                case NOT_EQUALS:
                case LIKE:
                case GREATER_OR_EQUALS_THAN:
                case GREATER_THAN:
                case LOWER_OR_EQUALS_THAN:
                case LOWER_THAN:
                    query.append(buildQueryWithSingleParameter(criterion));
                    break;
                case BETWEEN:
                case NOT_BETWEEN:
                    query.append(buildBetweenQuery(criterion));
                    break;
                case IS_NOT_NULL:
                case IS_NULL:
                    query.append(buildQueryWithoutParameter(criterion));
                    break;
                case NOT_IN:
                case IN:
                    query.append(buildQueryWithMultipleParameters(criterion));
                    break;
            }

        } else {

            CriteriaLogicConnector criteriaLogicConnector = criterion.getCriteriaLogicConnector();
            int size = criterion.getSubCriteria().size();
            int index = 0;

            for (QueryCriterion c : criterion.getSubCriteria()) {
                query
                        .append("(")
                        .append(buildQuery(c))
                        .append(")");

                if ((++index) < size) {
                    query.append(criteriaLogicConnector.equals(CriteriaLogicConnector.AND) ? " AND " : " OR ");
                }

            }

        }

        return query.toString();
    }

    private String buildQueryWithoutParameter(QueryCriterion criterion) {
        StringBuilder query = new StringBuilder("");
        query
                .append(criterion.getNomColonne())
                .append(" ")
                .append(criterion.getOperateur().getValue());
        return query.toString();
    }

    private String buildQueryWithSingleParameter(QueryCriterion criterion) {
        StringBuilder query = new StringBuilder("");
        if (criterion.getOperateur().equals(Operateur.LIKE)) {
            query
                    .append("LOWER(")
                    .append(criterion.getNomColonne())
                    .append(") LIKE LOWER(?)");
        } else {
            query
                    .append(criterion.getNomColonne())
                    .append(" ")
                    .append(criterion.getOperateur().getValue())
                    .append(" ?");
        }

        return query.toString();
    }

    private String buildBetweenQuery(QueryCriterion criterion) {
        StringBuilder query = new StringBuilder("");
        query
                .append(criterion.getNomColonne())
                .append(" ")
                .append(criterion.getOperateur().getValue())
                .append(" ? ")
                .append(" AND ")
                .append(" ? ");
        return query.toString();
    }

    private String buildQueryWithMultipleParameters(QueryCriterion criterion) {
        StringBuilder query = new StringBuilder("");

        query
                .append(criterion.getNomColonne())
                .append(" ")
                .append(criterion.getOperateur().getValue())
                .append("(");

        List values = (List) criterion.getCriteriaValue();

        int size = values.size();
        for (int i = 0; i < size; i++) {

            if ((i + 1) < size) {
                query.append("?,");
            } else {
                query.append("?");
            }

        }

        query.append(")");

        return query.toString();
    }
}