import { testSuite, expect } from "manten";
import { nrml, testCollection } from "../../../common";

export default testSuite(async ({ describe }) => {
  describe("$fn", ({ test }) => {
    test("works", () => {
      const collection = testCollection();
      collection.insert([
        { a: 2 },
        { a: 4 },
        { a: 5 },
        { a: 6 },
      ]);
      const isEven = (x: number) => x % 2 === 0;
      const found = nrml(collection.find({ a: { $fn: isEven } }));
      expect(found).toEqual([{ a: 2 }, { a: 4 }, { a: 6 }]);
    });
    test("nested", () => {
      const collection = testCollection();
      collection.insert([
        { a: { b: { c: 2 } } },
        { a: { b: { c: 4 } } },
        { a: { b: { c: 5 } } },
        { a: { b: { c: 6 } } },
      ]);
      const isEven = (x: number) => x % 2 === 0;
      const found = nrml(collection.find({ c: { $fn: isEven } }));
      expect(found).toEqual([ { a: { b: { c: 2 } } }, { a: { b: { c: 4 } } }, { a: { b: { c: 6 } } } ]);
    });
    test("nested, using dot notation", () => {
      const collection = testCollection();
      collection.insert([
        { a: { b: { c: 2 } } },
        { a: { b: { c: 4 } } },
        { a: { b: { c: 5 } } },
        { a: { b: { c: 6 } } },
      ]);
      const isEven = (x: number) => x % 2 === 0;
      const found = nrml(collection.find({ "a.b.c": { $fn: isEven } }));
      expect(found).toEqual([ { a: { b: { c: 2 } } }, { a: { b: { c: 4 } } }, { a: { b: { c: 6 } } } ]);
    });
    test("multiple functions", () => {
      // When using multiple functions, the source value must be true
      // for each function in order to be considered a query match.
      const collection = testCollection();
      collection.insert([
        { a: 2 },
        { a: 3 },
        { a: 4 },
        { a: 5 },
        { a: 6 },
      ]);
      const isOdd = (x: number) => x % 2 !== 0;
      const isThree = (x: number) => x === 3;
      const found = nrml(collection.find({ a: { $fn: [isThree, isOdd] } }));
      expect(found).toEqual([{ a: 3 }]);
    });
  });
});