import { useStateHook } from "./useStateHook";
import { EventsManager } from "../EventsManager";
import { CallbacksManager } from "../CallbacksManager";
import { ElementState } from "../ElementState";
import { IElementParams, EventType } from "../types";

describe("useStateHook tests", () => {
    const elementId = 15;
    let eventsManager: EventsManager;
    let callbacksManager: CallbacksManager;
    let state: ElementState;
    const params: IElementParams = {
        args: ["arg1", "arg2"],
        func: jest.fn(),
    };
    const callback1 = jest.fn();
    const callbackId1 = 20;
    let createEvent: jest.Mock;
    let getCallback: jest.Mock;
    beforeEach(() => {
        callbacksManager = new CallbacksManager();
        eventsManager = new EventsManager(callbacksManager);
        state = new ElementState(params);
        createEvent = jest.fn().mockReturnValue([callbackId1, callback1]);
        eventsManager.createEvent = createEvent;
        getCallback = jest.fn().mockImplementation((id: number) => {
            if (id === callbackId1) {
                return callback1;
            }
            throw new Error("Unknown callback id " + id);
        });
        callbacksManager.getCallback = getCallback;
    });
    it("when first tick, should add var to state, create setter and return state", () => {
        const [value, setValue] = useStateHook(eventsManager, callbacksManager, elementId, state, "DefaultValue");
        expect(createEvent.mock.calls.length).toBe(1);
        const event = createEvent.mock.calls[0];
        expect(event).toEqual([
            elementId,
            EventType.ChangeVar,
            {
                varNumber: 0,
            },
        ]);
        expect(state.vars.length).toBe(1);
        expect(state.vars[0]).toEqual({ value: "DefaultValue", setter: callbackId1 });
        expect(value).toBe("DefaultValue");
        expect(setValue).toBe(callback1);
        expect(state.tickState.currentVarNumber).toBe(1);
    });
    it("when not first tick and vars not found should throw error", () => {
        state.isFirstTick = false;
        state.tickState.currentVarNumber = 1;
        expect(() => useStateHook(eventsManager, callbacksManager, elementId, state, "DefaultValue")).toThrowError(
            "Expected var with number " + state.tickState.currentVarNumber,
        );
    });
    it("when not first tick and var exists, should return state", () => {
        state.isFirstTick = false;
        const value1 = "Value1";
        state.vars.push({
            value: value1,
            setter: callbackId1,
        });
        const result = useStateHook(eventsManager, callbacksManager, elementId, state, "DefaultValue3");
        expect(result[0]).toBe(value1);
        expect(result[1]).toBe(callback1);
        expect(state.tickState.currentVarNumber).toBe(1);
    });
});