import { describe, expect, it } from "vitest";
import {
	calcPagination,
	PER_PAGE_OPTIONS,
	parseListParams,
} from "./admin-helpers";

describe("parseListParams", () => {
	it("parses defaults", () => {
		const p = parseListParams(new URLSearchParams());
		expect(p).toEqual({
			search: "",
			perPage: 20,
			page: 1,
			sort: undefined,
			order: "desc",
		});
	});

	it("parses explicit values", () => {
		const p = parseListParams(
			new URLSearchParams("search=sofa&perPage=50&page=3&sort=name&order=asc"),
		);
		expect(p.search).toBe("sofa");
		expect(p.perPage).toBe(50);
		expect(p.page).toBe(3);
		expect(p.sort).toBe("name");
		expect(p.order).toBe("asc");
	});

	it("clamps perPage to [1, 100]", () => {
		expect(parseListParams(new URLSearchParams("perPage=0")).perPage).toBe(1);
		expect(parseListParams(new URLSearchParams("perPage=1000")).perPage).toBe(
			100,
		);
	});

	it("clamps page to >= 1", () => {
		expect(parseListParams(new URLSearchParams("page=0")).page).toBe(1);
		expect(parseListParams(new URLSearchParams("page=-5")).page).toBe(1);
	});

	it("defaults order to desc when not asc", () => {
		expect(parseListParams(new URLSearchParams("order=asc")).order).toBe("asc");
		expect(parseListParams(new URLSearchParams("order=desc")).order).toBe(
			"desc",
		);
		expect(parseListParams(new URLSearchParams("order=bogus")).order).toBe(
			"desc",
		);
	});
});

describe("calcPagination", () => {
	it("computes last page, offset and clamps the page", () => {
		const p = calcPagination(50, 3, 20);
		expect(p.lastPage).toBe(3);
		expect(p.page).toBe(3);
		expect(p.offset).toBe(40);
	});

	it("clamps page beyond last page", () => {
		const p = calcPagination(10, 99, 20);
		expect(p.lastPage).toBe(1);
		expect(p.page).toBe(1);
		expect(p.offset).toBe(0);
	});

	it("handles zero total with lastPage 1", () => {
		const p = calcPagination(0, 1, 20);
		expect(p.lastPage).toBe(1);
		expect(p.offset).toBe(0);
	});
});

describe("PER_PAGE_OPTIONS", () => {
	it("exposes the selectable page sizes", () => {
		expect(PER_PAGE_OPTIONS).toEqual([10, 20, 50]);
	});
});