aurasphere/gomorra-sql

package co.aurasphere.gomorrasql.states;

import java.util.Arrays;

import co.aurasphere.gomorrasql.Keywords;
import co.aurasphere.gomorrasql.model.CaggiaFaException;
import co.aurasphere.gomorrasql.model.QueryInfo;
import co.aurasphere.gomorrasql.model.QueryInfo.QueryType;
import co.aurasphere.gomorrasql.states.query.OptionalWhereState;
import co.aurasphere.gomorrasql.states.query.SelectColumnsState;
import co.aurasphere.gomorrasql.states.query.UpdateSetState;

/**
 * First state when parsing a query. It switches through the various possible
 * queries according to the first token.
 * 
 * @author Donato Rimenti
 *
 */
public class InitialState extends AbstractState {

    public InitialState() {
        super(new QueryInfo());
    }

    @Override
    public AbstractState transitionToNextState(String token) throws CaggiaFaException {
        if (token.equalsIgnoreCase(Keywords.SELECT_KEYWORD)) {
            queryInfo.setType(QueryType.SELECT);
            return new SelectColumnsState(queryInfo);
        }
        if (token.equalsIgnoreCase(Keywords.UPDATE_KEYWORD)) {
            queryInfo.setType(QueryType.UPDATE);
            return new AnyTokenConsumerState(queryInfo, queryInfo::setTableName,
                    q -> new SingleTokenMatchState(q, Keywords.SET_KEYWORD,
                            q2 -> new AnyTokenConsumerState(q2, q2::addColumnName,
                                    q3 -> new SingleTokenMatchState(q3, Keywords.SET_EQUAL_KEYWORD,
                                            q4 -> new AnyTokenConsumerState(q4, q4::addValue, UpdateSetState::new)))));
        }
        if (token.equalsIgnoreCase(Keywords.DELETE_KEYWORDS[0])) {
            queryInfo.setType(QueryType.DELETE);
            return new GreedyMatchKeywordState(queryInfo, Keywords.DELETE_KEYWORDS,
                    q -> new GreedyMatchKeywordState(q, Keywords.FROM_KEYWORDS,
                            q2 -> new AnyTokenConsumerState(q2, q2::setTableName, OptionalWhereState::new), 0));
        }
        if (token.equalsIgnoreCase(Keywords.INSERT_KEYWORDS[0])) {
            queryInfo.setType(QueryType.INSERT);
            return new GreedyMatchKeywordState(queryInfo, Keywords.INSERT_KEYWORDS,
                    q -> new AnyTokenConsumerState(q, q::setTableName,
                            q2 -> new CommaSeparedValuesState(q2, q2.getColumnNames(), Keywords.VALUES_KEYWORD,
                                    "%COLUMN_NAME%", true, false, q3 -> new CommaSeparedValuesState(q3, q3.getValues(),
                                            null, "%VALUE%", true, true, FinalState::new))));
        }
        if (token.equalsIgnoreCase(Keywords.COMMIT_KEYWORDS[0])) {
            queryInfo.setType(QueryType.COMMIT);
            return new GreedyMatchKeywordState(queryInfo, Keywords.COMMIT_KEYWORDS, FinalState::new);
        }
        if (token.equalsIgnoreCase(Keywords.ROLLBACK_KEYWORD)) {
            queryInfo.setType(QueryType.ROLLBACK);
            return new FinalState(queryInfo);
        }
        if (token.equalsIgnoreCase(Keywords.BEGIN_TRANSACTION_KEYWORDS[0])) {
            queryInfo.setType(QueryType.BEGIN_TRANSACTION);
            return new GreedyMatchKeywordState(queryInfo, Keywords.BEGIN_TRANSACTION_KEYWORDS, FinalState::new);
        }
        throw new CaggiaFaException(Arrays.asList(Keywords.SELECT_KEYWORD, Keywords.UPDATE_KEYWORD,
                Keywords.INSERT_KEYWORDS[0], Keywords.DELETE_KEYWORDS[0], Keywords.BEGIN_TRANSACTION_KEYWORDS[0],
                Keywords.COMMIT_KEYWORDS[0], Keywords.ROLLBACK_KEYWORD), token);
    }

}