datum-focus/src/model/field/field.ts

Data shape, model, metadata, JSON, JSON Schema, GraphQL, MongoDB query and aggregations, iterator generators

import { ARRAY } from "../../array";
import { BooleanType } from "../../boolean";
import { DateType } from "../../date";
import { IntegerType, NumberType } from "../../number";
import { DICTIONARY, KnownRecord, RECORD, RecordType } from "../../record";
import { StringType } from "../../string";

export type PrimitiveNameOf<T> = T extends Boolean
  ? BooleanType
  : T extends Date
  ? DateType
  : T extends BigInt
  ? IntegerType
  : T extends Number
  ? NumberType
  : T extends String
  ? StringType
  : RecordType;

type FieldsOf<T> = typeof RECORD | [string, typeof RECORD] | FieldMap<T>;
type ArrayOf<U> = U extends KnownRecord
  ?
  | [FieldMap<U> | typeof RECORD, typeof ARRAY]
  | [string, typeof RECORD, typeof ARRAY]
  : [PrimitiveNameOf<U>, typeof ARRAY];
type DictionaryOf<V> = V extends KnownRecord
  ?
  | typeof RECORD
  | [string, typeof RECORD, typeof DICTIONARY, StringType?]
  | [typeof RECORD, typeof DICTIONARY, StringType?]
  | [FieldMap<V>, typeof DICTIONARY, StringType?] // [model name, , , key type]
  : [PrimitiveNameOf<V>, typeof DICTIONARY, StringType?]; // [type, , key type]
export type TypeOf<T> = T extends Array<infer U>
  ? ArrayOf<U>
  : T extends Record<string, infer V>
  ? DictionaryOf<V> // [type, , key type]
  : T extends KnownRecord
  ? FieldsOf<T>
  : PrimitiveNameOf<T>;

export interface FieldModel<T> {
  default?: T;
  name: string;
  type: TypeOf<T>;
}

export type FieldDescriptor<T> = Omit<FieldModel<T>, "name">;
export type FieldMap<T extends {}> = {
  [P in keyof T]: FieldDescriptor<T[P]>;
};