import { mount } from '@vue/test-utils';
import { describe, expect, it } from 'vitest';
import { defineComponent, h, nextTick, shallowRef } from 'vue';
import { useMaintenanceWindow } from '@/composables/useMaintenanceWindow';
import type { JourneySnapshot } from '@/journey/types';
import {
  createMaintenanceDirection,
  maintenanceClock,
  maintenanceProgress,
  maintenanceStep,
  maintenanceSubline,
} from '@/journey/maintenance-progress';
import type { SectionId } from '@/content/types';

const at = (
  activeSectionId: SectionId,
  activeHeadingOffsetVh: number,
  nextHeadingOffsetVh: number | null,
) => ({
  activeSectionId,
  sectionActivation: { layoutRevision: 1, activeHeadingOffsetVh, nextHeadingOffsetVh },
});

const live = () => '14:07';

describe('maintenance progress', () => {
  it('is 0 at the Infrastructure heading and 1 at the next heading', () => {
    expect(maintenanceProgress(at('infrastructure', 0, 2.5))).toBe(0);
    expect(maintenanceProgress(at('infrastructure', -1.25, 1.25))).toBeCloseTo(0.5);
    expect(maintenanceProgress(at('infrastructure', -2.5, 0))).toBe(1);
  });

  it('clamps to the window and is null outside the chapter or without geometry', () => {
    expect(maintenanceProgress(at('infrastructure', 0.2, 2.7))).toBe(0);
    expect(maintenanceProgress(at('infrastructure', -3, -0.5))).toBe(1);
    expect(maintenanceProgress(at('experience', -1, 1))).toBeNull();
    expect(maintenanceProgress(at('selected-builds', -1, 1))).toBeNull();
    expect(maintenanceProgress(at('infrastructure', 0, null))).toBeNull();
    expect(maintenanceProgress(at('infrastructure', 1, 1))).toBeNull();
    expect(maintenanceProgress(at('infrastructure', Number.NaN, 1))).toBeNull();
  });

  it('maps progress onto open, backup, transfer, verify and done', () => {
    expect(maintenanceStep(0)).toBe('open');
    expect(maintenanceStep(0.099)).toBe('open');
    expect(maintenanceStep(0.1)).toBe('backup');
    expect(maintenanceStep(0.349)).toBe('backup');
    expect(maintenanceStep(0.35)).toBe('transfer');
    expect(maintenanceStep(0.649)).toBe('transfer');
    expect(maintenanceStep(0.65)).toBe('verify');
    expect(maintenanceStep(0.899)).toBe('verify');
    expect(maintenanceStep(0.9)).toBe('done');
    expect(maintenanceStep(1)).toBe('done');
  });

  it('holds the clock at 03:12 while the window opens, cuts over at 03:51, then goes live', () => {
    expect(maintenanceClock(0, live)).toBe('03:12');
    expect(maintenanceClock(0.1, live)).toBe('03:12');
    expect(maintenanceClock(0.5, live)).toBe('03:32');
    expect(maintenanceClock(0.9, live)).toBe('03:51');
    expect(maintenanceClock(0.999, live)).toBe('03:51');
    expect(maintenanceClock(1, live)).toBe('14:07');
    let previous = -1;
    for (let p = 0; p < 1; p += 0.01) {
      const minutes = Number(maintenanceClock(p, live).slice(3));
      expect(minutes).toBeGreaterThanOrEqual(previous);
      previous = minutes;
    }
  });

  it('writes the sub-line from the step, and a rollback while reversing', () => {
    expect(maintenanceSubline(0.02, false, live)).toBe('MAINTENANCE WINDOW · 03:12');
    expect(maintenanceSubline(0.92, false, live)).toBe('CUTOVER OK · 03:51');
    expect(maintenanceSubline(0.5, true, live)).toMatch(/^ROLLBACK CHECKPOINT · 03:\d\d$/u);
    expect(maintenanceSubline(0.97, false, live)).toBe('CUTOVER OK · 03:51');
  });

  it('latches a rollback while progress falls and clears it when it rises', () => {
    const track = createMaintenanceDirection();
    expect(track(0.2)).toBe(false);
    expect(track(0.3)).toBe(false);
    expect(track(0.25)).toBe(true);
    expect(track(0.25)).toBe(true);
    expect(track(0.2505)).toBe(true);
    expect(track(0.3)).toBe(false);
    expect(track(0.2)).toBe(true);
    expect(track(null)).toBe(false);
    expect(track(0.9)).toBe(false);
    expect(track(0)).toBe(false);
  });
});

describe('useMaintenanceWindow', () => {
  const snapshot = (activeSectionId: SectionId, a: number, n: number | null): JourneySnapshot => ({
    scrollY: 0,
    routeProgress: 0.4,
    direction: 0,
    acceleration: 0,
    driveSpeed: 0,
    activeSectionId,
    chapter: 'infrastructure',
    sign: null,
    arrived: false,
    sectionActivation: { layoutRevision: 1, activeHeadingOffsetVh: a, nextHeadingOffsetVh: n },
  });

  it('steps html[data-maintenance-step] and the sub-line from scroll, then cleans up', async () => {
    const journey = shallowRef(snapshot('experience', -1, 1));
    let subline = shallowRef('');
    const wrapper = mount(defineComponent({
      setup() {
        subline = useMaintenanceWindow(journey) as typeof subline;
        return () => h('span', subline.value);
      },
    }));
    const root = document.documentElement;
    await nextTick();
    expect(root.dataset.maintenanceStep).toBeUndefined();
    expect(subline.value).toBe('');

    journey.value = snapshot('infrastructure', 0, 2);
    await nextTick();
    expect(root.dataset.maintenanceStep).toBe('open');
    expect(subline.value).toBe('MAINTENANCE WINDOW \u00b7 03:12');

    journey.value = snapshot('infrastructure', -1.84, 0.16);
    await nextTick();
    expect(root.dataset.maintenanceStep).toBe('done');
    expect(subline.value).toBe('CUTOVER OK \u00b7 03:51');

    journey.value = snapshot('infrastructure', -1, 1);
    await nextTick();
    expect(root.dataset.maintenanceStep).toBe('transfer');
    expect(subline.value).toMatch(/^ROLLBACK CHECKPOINT/u);

    journey.value = snapshot('selected-builds', 0, 2);
    await nextTick();
    expect(root.dataset.maintenanceStep).toBeUndefined();
    expect(subline.value).toBe('');

    journey.value = snapshot('infrastructure', -0.4, 1.6);
    await nextTick();
    expect(root.dataset.maintenanceStep).toBe('backup');
    wrapper.unmount();
    expect(root.dataset.maintenanceStep).toBeUndefined();
  });
});