/*
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 * Click nbfs://nbhost/SystemFileSystem/Templates/Classes/Class.java to edit this template
 */
package com.megatim.fdxcommons.tools.database.queries;

import com.megatim.fdxcommons.model.pojo.JsonTableDefinition;
import com.megatim.fdxcommons.tools.database.contrat.DefaultPreparedStatementProcessor;
import com.megatim.fdxcommons.tools.database.contrat.QueryMetaData;
import com.megatim.fdxcommons.tools.database.queries.metadata.QueryCriterion;
import com.megatim.fdxcommons.tools.database.queries.metadata.WhereQueryParameters;
import com.megatim.fdxcommons.tools.database.tables.appcolumns.IndexColumnDefinition;
import com.megatim.fdxcommons.tools.database.tables.appcolumns.ParentIdColumnDefinition;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.List;
import java.util.Map;

/**
 *
 * @author ASUS
 */
public class JsonCountQuery implements QueryMetaData<Long> {

    private final JsonTableDefinition tableDefinition;
    private final Connection connection;
    private final QueryCriterion queryCriterion;
    private final Map<String, String> tablesNameToAlias;

    public JsonCountQuery(JsonTableDefinition tableDefinition, QueryCriterion queryCriterion, Connection connection, Map<String, String> tablesNameToAlias) {
        this.connection = connection;
        this.queryCriterion = queryCriterion;
        this.tableDefinition = tableDefinition;
        this.tablesNameToAlias = tablesNameToAlias;
    }

    @Override
    public Long execute() throws Exception {
        String query = countString() + fromString() + joinString() + whereString();
        System.out.println("countQuery = " + query);
        try ( PreparedStatement statement = connection.prepareStatement(query)) {

            new DefaultPreparedStatementProcessor().process(statement, new WhereQueryParameters(queryCriterion).parameters());
            ResultSet resultSet = statement.executeQuery();

            if (resultSet.next()) {
                return resultSet.getLong(1);
            }
            return 0L;
        }
    }

    private String countString() {
        StringBuilder query = new StringBuilder("SELECT COUNT(");
        query.append("DISTINCT(")
                .append(tablesNameToAlias.get(tableDefinition.getTableName()))
                .append(".")
                .append(new IndexColumnDefinition().name())
                .append("))");

        return query.toString();
    }

    private String whereString() {
        return "\n" + new WhereQueryString(queryCriterion).query();
    }

    private String fromString() {
        StringBuilder fromPart = new StringBuilder("\nFROM ");
        fromPart
                .append(tableDefinition.getTableName())
                .append(" ")
                .append(tablesNameToAlias.get(tableDefinition.getTableName()));

        return fromPart.toString();
    }

    private String joinString() {
        return joinString(tableDefinition.getTablesDefinition());
    }

    private String joinString(List<JsonTableDefinition> tablesDef) {
        StringBuilder joinPart = new StringBuilder("");

        if (tablesNameToAlias.size() > 1) {
            for (JsonTableDefinition t : tablesDef) {
                joinPart.append(joinString(t));
                joinPart.append(joinString(t.getTablesDefinition()));
            }
        }
        return joinPart.toString();
    }

    private String joinString(JsonTableDefinition tableDef) {
        StringBuilder joinPart = new StringBuilder("\nJOIN ");
        joinPart.append(tableDef.getTableName())
                .append(" ")
                .append(tablesNameToAlias.get(tableDef.getTableName()))
                .append(" ON ")
                .append(tablesNameToAlias.get(tableDef.getTableName()))
                .append(".")
                .append(new ParentIdColumnDefinition().name())
                .append(" = ")
                .append(tablesNameToAlias.get(tableDef.getParentTableName()))
                .append(".")
                .append(new IndexColumnDefinition().name());

        return joinPart.toString();
    }
}