import { expect, test } from "@playwright/test";
import {
  estimateImageDispatchWaitMs,
  getAdaptiveImageQueueOwnerLimit,
} from "@/lib/canvas/image-queue-fairness";

test.describe("canvas image queue fairness", () => {
  test("lets one owner use the full model capacity without competition", () => {
    expect(
      getAdaptiveImageQueueOwnerLimit({
        maxConcurrent: 10,
        hasCompetingOwner: false,
      })
    ).toBe(10);
  });

  test("reserves half the slots when another owner is waiting", () => {
    expect(
      getAdaptiveImageQueueOwnerLimit({
        maxConcurrent: 10,
        hasCompetingOwner: true,
      })
    ).toBe(5);
    expect(
      getAdaptiveImageQueueOwnerLimit({
        maxConcurrent: 5,
        hasCompetingOwner: true,
      })
    ).toBe(3);
  });

  test("always keeps at least one executable slot", () => {
    expect(
      getAdaptiveImageQueueOwnerLimit({
        maxConcurrent: 0,
        hasCompetingOwner: true,
      })
    ).toBe(1);
  });

  test("estimates queue wait from request dispatch spacing, not generation duration", () => {
    expect(
      estimateImageDispatchWaitMs({
        queuePosition: 3,
        dispatchIntervalMs: 1000,
        delayRemainingMs: 400,
      })
    ).toBe(3400);
  });

  test("does not add wait after the request has no tasks ahead", () => {
    expect(
      estimateImageDispatchWaitMs({
        queuePosition: 0,
        dispatchIntervalMs: 1000,
      })
    ).toBe(0);
  });
});