// Add SqlDescribeCatalog & DescribeCatalogOperation
// Add SqlDescribeDatabase & DescribeDatabaseOperation
// Add SqlDescribeFunction & DescribeFunctionOperation

// Changed SqlNodes & Operations

// SqlShowCatalogs
public class SqlShowCatalogs extends SqlCall {

    public static final SqlSpecialOperator OPERATOR =
            new SqlSpecialOperator("SHOW CATALOGS", SqlKind.OTHER);
    // Add LIKE support
    protected final boolean notLike;
    protected final SqlCharStringLiteral likeLiteral;

    public SqlShowCatalogs(SqlParserPos pos) {
        super(pos);
        this.notLike = false;
        this.likeLiteral = null;
    }

    public SqlShowCatalogs(SqlParserPos pos, boolean notLike, SqlCharStringLiteral likeLiteral) {
        super(pos);
        this.notLike = notLike;
        this.likeLiteral = likeLiteral;
    }

    public boolean isNotLike() {
        return notLike;
    }

    public String getLikeSqlPattern() {
        return Objects.isNull(this.likeLiteral) ? null : likeLiteral.getValueAs(String.class);
    }

    public boolean isWithLike() {
        return Objects.nonNull(likeLiteral);
    }

    @Override
    public SqlOperator getOperator() {
        return OPERATOR;
    }

    @Override
    public List<SqlNode> getOperandList() {
        return Collections.emptyList();
    }

    @Override
    public void unparse(SqlWriter writer, int leftPrec, int rightPrec) {
        writer.keyword("SHOW CATALOGS");
        if (isWithLike()) {
            if (isNotLike()) {
                writer.keyword(String.format("NOT LIKE '%s'", getLikeSqlPattern()));
            } else {
                writer.keyword(String.format("LIKE '%s'", getLikeSqlPattern()));
            }
        }
    }
}

// ShowCatalogsOperation 
public class ShowCatalogsOperation implements ShowOperation {
    private final boolean withLike;
    private final boolean notLike;
    private final String likePattern;

    public ShowCatalogsOperation(boolean notLike, String likePattern) {
        this.withLike = likePattern != null;
        this.notLike = notLike;
        this.likePattern = likePattern;
    }

    public boolean isWithLike() {
        return withLike;
    }

    public boolean isNotLike() {
        return notLike;
    }

    public String getLikePattern() {
        return likePattern;
    }

    @Override
    public String asSummaryString() {
        StringBuilder builder = new StringBuilder().append("SHOW CATALOGS");
        if (withLike) {
            if (notLike) {
                builder.append(String.format(" %s LIKE %s", "NOT", likePattern));
            } else {
                builder.append(String.format(" LIKE %s", likePattern));
            }
        }
        return builder.toString();
    }
}

// SqlShowDatabases
public class SqlShowDatabases extends SqlCall {

    public static final SqlSpecialOperator OPERATOR =
            new SqlSpecialOperator("SHOW DATABASES", SqlKind.OTHER);
	
    // Add IN/FROM and LIKE support
    protected final SqlIdentifier catalogName;
    protected final String preposition;
    protected final boolean notLike;
    protected final SqlCharStringLiteral likeLiteral;

    public SqlShowDatabases(SqlParserPos pos) {
        super(pos);
        this.catalogName = null;
        this.preposition = null;
        this.notLike = false;
        this.likeLiteral = null;
    }

    public SqlShowDatabases(
            SqlParserPos pos,
            SqlIdentifier catalogName,
            String preposition,
            boolean notLike,
            SqlCharStringLiteral likeLiteral) {
        super(pos);
        this.preposition = preposition;
        this.catalogName =
                preposition != null
                        ? requireNonNull(catalogName, "Catalog name must not be null.")
                        : null;
        this.notLike = notLike;
        this.likeLiteral = likeLiteral;
    }

    public SqlIdentifier getCatalogName() {
        return catalogName;
    }

    public String catalogName() {
        return catalogName != null ? catalogName.getSimple() : null;
    }

    public String getPreposition() {
        return preposition;
    }

    public boolean isWithLike() {
        return Objects.nonNull(likeLiteral);
    }

    public boolean isNotLike() {
        return notLike;
    }

    public SqlCharStringLiteral getLikeLiteral() {
        return likeLiteral;
    }

    public String getLikeSqlPattern() {
        return Objects.isNull(this.likeLiteral) ? null : likeLiteral.getValueAs(String.class);
    }

    @Override
    public SqlOperator getOperator() {
        return OPERATOR;
    }

    @Override
    public List<SqlNode> getOperandList() {
        return Objects.isNull(this.catalogName)
                ? Collections.emptyList()
                : Collections.singletonList(catalogName);
    }

    @Override
    public void unparse(SqlWriter writer, int leftPrec, int rightPrec) {
        if (this.preposition == null) {
            writer.keyword("SHOW DATABASES");
        } else if (catalogName != null) {
            writer.keyword("SHOW DATABASES " + this.preposition);
            catalogName.unparse(writer, leftPrec, rightPrec);
        }
        if (isWithLike()) {
            if (isNotLike()) {
                writer.keyword(String.format("NOT LIKE '%s'", getLikeSqlPattern()));
            } else {
                writer.keyword(String.format("LIKE '%s'", getLikeSqlPattern()));
            }
        }
    }
}

// ShowDatabasesOperation
public class ShowDatabasesOperation implements ShowOperation {

    private final String preposition;
    private final String catalogName;
    private final boolean withLike;
    private final boolean notLike;
    private final String likePattern;

    public ShowDatabasesOperation() {
        this.preposition = null;
        this.catalogName = null;
        this.withLike = false;
        this.notLike = false;
        this.likePattern = null;
    }

    public ShowDatabasesOperation(boolean notLike, String likePattern) {
        this.preposition = null;
        this.catalogName = null;
        this.withLike = likePattern != null;
        this.notLike = notLike;
        this.likePattern = likePattern;
    }

    public ShowDatabasesOperation(
            String preposition, String catalogName, boolean notLike, String likePattern) {
        this.preposition = checkNotNull(preposition, "Preposition must not be null");
        this.catalogName = checkNotNull(catalogName, "Catalog name must not be null");
        this.withLike = likePattern != null;
        this.notLike = notLike;
        this.likePattern = likePattern;
    }

    public String getPreposition() {
        return preposition;
    }

    public String getCatalogName() {
        return catalogName;
    }

    public boolean isWithLike() {
        return withLike;
    }

    public boolean isNotLike() {
        return notLike;
    }

    public String getLikePattern() {
        return likePattern;
    }

    @Override
    public String asSummaryString() {
        StringBuilder builder = new StringBuilder().append("SHOW DATABASES");
        if (preposition != null) {
            builder.append(String.format(" %s %s", preposition, catalogName));
        }
        if (withLike) {
            if (notLike) {
                builder.append(String.format(" %s LIKE %s", "NOT", likePattern));
            } else {
                builder.append(String.format(" LIKE %s", likePattern));
            }
        }
        return builder.toString();
    }
}

// omit here. basically same as ShowCatalogs/ShowDatabases above.
// SqlShowFunctions & ShowFunctionsOperation
// SqlShowViews & ShowViewsOperation
// SqlShowModules & ShowModulesOperation
// SqlShowJars & ShowJarsOperation
// SqlShowJobs & ShowJobsOperation