flora-exception/src/FloraTypes/Document.ts

An exception system for FQL.

import { values } from "faunadb";
import {If,
    And,
    IsDoc, Select, Contains, ContainsPath} from "faunadb";
import { $Any } from "./Any";
import { $Object } from "./Object";
import { $Or } from "./Or";
import { $Ref, RefObjectI } from "./Ref";


/**
 * Document type predicate. Chcecks that any object is a document and has matching data.
 * @param Predicate is the predicate used to check the data.
 * @returns
 */
export const $Document = <T>(Predicate ? : (obj : any)=>obj is T) : (obj : any)=>obj is values.Document<T>=>{

    const name = `${Predicate ? Predicate.name : "$Unspecified"}Doc`;

    const map = {
        [name] : (obj : any) : obj is values.Document<T>=>{
            return Predicate ? If(
                And(IsDoc(obj), ContainsPath("data", obj)),
                Predicate(Select("data", obj)),
                false
            ) as unknown as boolean : IsDoc(obj) as unknown as boolean
        }
    }

    return map[name];

}