import { describe, it } from 'node:test';
import assert from 'node:assert';
import { DEFAULT_PROFILE, getEnergyLevelAtHour, isRecoveryWindow, energyScore, blocksRecovery, getWindowLabel } from '../lib/energy.js';
import { findFreeSlots, suggestSlot, energyOverlayForDay } from '../lib/scheduler.js';
import type { CalendarEvent } from '../lib/calendar.js';

describe('energy', () => {
  it('returns correct energy level at hour 10 (deep work peak)', () => {
    assert.strictEqual(getEnergyLevelAtHour(DEFAULT_PROFILE, 10), 5);
  });

  it('returns recovery at hour 12 (lunch)', () => {
    assert.strictEqual(isRecoveryWindow(DEFAULT_PROFILE, 12), true);
  });

  it('returns recovery at hour 3 (overnight sleep)', () => {
    assert.strictEqual(isRecoveryWindow(DEFAULT_PROFILE, 3), true);
  });

  it('energyScore for 9-12 window is 5.0', () => {
    assert.strictEqual(energyScore(DEFAULT_PROFILE, 9, 3), 5.0);
  });

  it('blocksRecovery for 60 min starting at 11:30 overlaps lunch recovery', () => {
    assert.strictEqual(blocksRecovery(DEFAULT_PROFILE, 11, 60), true);
  });

  it('does not block recovery at 9am for 60 min', () => {
    assert.strictEqual(blocksRecovery(DEFAULT_PROFILE, 9, 60), false);
  });

  it('getWindowLabel returns Deep Work Peak at 10', () => {
    assert.strictEqual(getWindowLabel(DEFAULT_PROFILE, 10), 'Deep Work Peak');
  });
});

describe('scheduler', () => {
  const events: CalendarEvent[] = [
    { id: '1', summary: 'Meeting', start: { dateTime: '2024-06-15T09:00:00' }, end: { dateTime: '2024-06-15T10:00:00' } },
    { id: '2', summary: 'Lunch', start: { dateTime: '2024-06-15T12:00:00' }, end: { dateTime: '2024-06-15T13:00:00' } },
  ];

  it('findFreeSlots returns slots between 6am and 9am, and 10am-12pm', () => {
    const slots = findFreeSlots(events, DEFAULT_PROFILE, new Date('2024-06-15'), 30);
    assert.ok(slots.length >= 2, `Expected at least 2 slots, got ${slots.length}`);
    const firstSlot = slots[0];
    assert.strictEqual(firstSlot.start.getHours(), 6);
    assert.strictEqual(firstSlot.end.getHours(), 9);
  });

  it('suggestSlot picks highest energy non-recovery slot for 60 min', () => {
    const suggestion = suggestSlot('Deep Work', 60, events, DEFAULT_PROFILE, new Date('2024-06-15'));
    assert.ok(suggestion, 'Expected a suggestion');
    if (!suggestion) return;
    assert.ok(suggestion.energyScore >= 3, `Expected decent energy score, got ${suggestion.energyScore}`);
    assert.ok(suggestion.suggestedStart.getHours() >= 6, 'Should start after 6am');
  });

  it('suggestSlot returns null when no free time exists', () => {
    const allDay: CalendarEvent[] = [
      { id: 'x', summary: 'All Day', start: { dateTime: '2024-06-15T06:00:00' }, end: { dateTime: '2024-06-15T22:00:00' } },
    ];
    const suggestion = suggestSlot('Task', 60, allDay, DEFAULT_PROFILE, new Date('2024-06-15'));
    assert.strictEqual(suggestion, null);
  });

  it('energyOverlayForDay returns 24 items', () => {
    const overlay = energyOverlayForDay(DEFAULT_PROFILE, new Date('2024-06-15'));
    assert.strictEqual(overlay.length, 24);
    assert.strictEqual(overlay[10].level, 5);
    assert.strictEqual(overlay[12].isRecovery, true);
  });

  it('findFreeSlots respects minDuration', () => {
    const shortEvents: CalendarEvent[] = [
      { id: '1', summary: 'A', start: { dateTime: '2024-06-15T06:00:00' }, end: { dateTime: '2024-06-15T06:45:00' } },
      { id: '2', summary: 'B', start: { dateTime: '2024-06-15T06:50:00' }, end: { dateTime: '2024-06-15T22:00:00' } },
    ];
    const slots = findFreeSlots(shortEvents, DEFAULT_PROFILE, new Date('2024-06-15'), 30);
    // 5 min gap between 6:45 and 6:50 is less than 30 min minDuration, so should be 0 slots
    assert.strictEqual(slots.length, 0, 'Should not return sub-minDuration gap');
  });
});