import { describe, it, expect } from 'vitest';
import { advanceGrowth, GROWTH_THRESHOLDS } from './growth';
import { PLANT_TYPES } from './plants';
import type { PlantInstance } from './types';

const rosemary = PLANT_TYPES.rosemary;
const yarrow = PLANT_TYPES.yarrow;
const winterRose = PLANT_TYPES['winter-rose'];

function plant(plantedAtTick: number, plantTypeId: PlantInstance['plantTypeId'] = 'rosemary'): PlantInstance {
  return { plantedAtTick, plantTypeId };
}

describe('advanceGrowth (D-08, D-09; pure function of currentTick + duration)', () => {
  it('returns sprout at tick=plantedAtTick', () => {
    expect(advanceGrowth(plant(0), rosemary, 0)).toBe('sprout');
  });

  it('returns sprout just below the 33% mature threshold', () => {
    // 600 * 0.33 = 198. Tick 197 is below the threshold.
    expect(advanceGrowth(plant(0), rosemary, 197)).toBe('sprout');
  });

  it('returns mature at the 33% threshold (≥, not >)', () => {
    expect(advanceGrowth(plant(0), rosemary, 198)).toBe('mature');
  });

  it('returns mature just below the ready threshold', () => {
    expect(advanceGrowth(plant(0), rosemary, 599)).toBe('mature');
  });

  it('returns ready at the duration boundary (100%)', () => {
    expect(advanceGrowth(plant(0), rosemary, 600)).toBe('ready');
  });

  it('returns sprout when just planted (currentTick === plantedAtTick != 0)', () => {
    expect(advanceGrowth(plant(100), rosemary, 100)).toBe('sprout');
  });

  it('clamps negative deltas to sprout (Pitfall 1 — system-clock rewind defense)', () => {
    expect(advanceGrowth(plant(100), rosemary, 50)).toBe('sprout');
  });

  it('overgrowth stays at ready (no overflow stage)', () => {
    expect(advanceGrowth(plant(0), rosemary, 100000)).toBe('ready');
  });

  it('respects per-plant duration — yarrow at 900 ticks is ready', () => {
    // Yarrow 33% threshold = 297; 900 = ready.
    expect(advanceGrowth(plant(0), yarrow, 296)).toBe('sprout');
    expect(advanceGrowth(plant(0), yarrow, 297)).toBe('mature');
    expect(advanceGrowth(plant(0), yarrow, 899)).toBe('mature');
    expect(advanceGrowth(plant(0), yarrow, 900)).toBe('ready');
  });

  it('respects per-plant duration — winter-rose at 1500 ticks is ready', () => {
    // 1500 * 0.33 = 495.
    expect(advanceGrowth(plant(0), winterRose, 494)).toBe('sprout');
    expect(advanceGrowth(plant(0), winterRose, 495)).toBe('mature');
    expect(advanceGrowth(plant(0), winterRose, 1499)).toBe('mature');
    expect(advanceGrowth(plant(0), winterRose, 1500)).toBe('ready');
  });

  it('GROWTH_THRESHOLDS is frozen (no accidental mutation)', () => {
    expect(Object.isFrozen(GROWTH_THRESHOLDS)).toBe(true);
  });
});