import { describe, expect, it } from "@suaveplan/testing/runner";
import fc from "fast-check";
import { mergeOpenAPIDocuments } from "../src/merger/merger.js";
import type { OpenAPIDocument } from "../src/types/openapi.js";

const operationArb = fc.record({
    responses: fc.constant({}),
});

const pathItemArb = fc.dictionary(
    fc.constantFrom("get", "post", "put", "patch", "delete"),
    operationArb,
    { minKeys: 1, maxKeys: 3 }
);

const pathsArb = fc.dictionary(
    fc.string({ minLength: 1, maxLength: 10 }).map((s) => `/${s}`),
    pathItemArb,
    { minKeys: 0, maxKeys: 5 }
);

const docArb = pathsArb.map<OpenAPIDocument>((paths) => ({
    openapi: "3.1.0",
    info: { title: "T", version: "1.0.0" },
    paths,
}));

describe("mergeOpenAPIDocuments — associativity property", () => {
    it("merge(a, b, c) === merge(merge(a, b), c) for arbitrary path sets", {
        timeout: 30000,
    }, () => {
        fc.assert(
            fc.property(docArb, docArb, docArb, (a, b, c) => {
                const left = mergeOpenAPIDocuments(a, b, c);
                const right = mergeOpenAPIDocuments(
                    mergeOpenAPIDocuments(a, b),
                    c
                );
                expect(right.paths).toEqual(left.paths);
            }),
            { numRuns: 200 }
        );
    });

    it("merging with empty extras is idempotent on paths", {
        timeout: 30000,
    }, () => {
        fc.assert(
            fc.property(docArb, (a) => {
                const m = mergeOpenAPIDocuments(a, {}, {}, {});
                expect(m.paths).toEqual(a.paths);
            }),
            { numRuns: 100 }
        );
    });
});