export interface ISparJson {
  distinct?: boolean;
  variables: Array<VariableTerm | VariableExpression>;
  order?: Order;
  branches: Array<Branch>;
  limit?: number;
}

export interface Branch {
  line: CriteriaLine;
  children: Array<Branch> | [];
  optional?: boolean;
  notExists?: boolean;
}

export interface VariableTerm {
  termType: "Variable",
  value: string
}

export interface VariableExpression {
  expression: {
    type: "aggregate",
    aggregation: string,
    distinct: boolean,
    expression: VariableTerm,
  },
  variable : VariableTerm
}

export interface CriteriaLine {
  s: string;  
  p: string;
  o: string;
  sType: string;
  oType: string;
  // see ../components/widgets/AbstractWidget
  // we are not making an explicit reference to this dependency
  values: {label:string}[];
}

export enum Order {
  ASC = "asc",
  DESC = "desc",
  NOORDER = "noord",
}

export enum AggregateFunction {
  COUNT = "count",
  MAX = "max",
  MIN = "min",
  SUM = "sum",
  GROUP_CONCAT = "group_concat",
  SAMPLE = "sample",
  AVG = "avg"
}