import { describe, expect, it } from 'vitest'
import {
  generateInitialCondition,
  getInitialConditionRuntime,
  listInitialConditionRuntimes,
  registerInitialConditionRuntime
} from '../admin/src/caInitialConditionGenerators.js'

describe('CA initial condition runtimes', () => {
  it('registers the built-in random soup generator', () => {
    expect(listInitialConditionRuntimes().map((runtime) => runtime.id)).toContain('random-soup')
    expect(getInitialConditionRuntime('random-soup')?.label).toBe('Random soup')
  })

  it('generates deterministic cell coordinates for the same seed and density', () => {
    const input = {
      caClass: { dimensions: 2, states: 2 },
      settings: { simulation: { grid: { size: [5, 5, 1] } } },
      params: { density: 0.35, seed: 'repeatable' }
    }

    expect(generateInitialCondition('random-soup', input)).toEqual(generateInitialCondition('random-soup', input))
  })

  it('clamps density and records generator provenance in the persisted initial condition', () => {
    const generated = generateInitialCondition('random-soup', {
      caClass: { dimensions: 2, states: 2 },
      settings: { simulation: { grid: { size: [3, 3, 1] } } },
      params: { density: 2, seed: 'full' }
    })

    expect(generated.cells).toHaveLength(9)
    expect(generated.generator).toEqual({ kind: 'random-soup', density: 1, seed: 'full' })
  })

  it('lets custom initial condition runtimes plug into the same contract', () => {
    registerInitialConditionRuntime({
      id: 'test-single-cell',
      label: 'Test single cell',
      generate: () => ({ type: 'cells', cells: [[1, 1, 0]], generator: { kind: 'test-single-cell' } })
    })

    expect(generateInitialCondition('test-single-cell', {
      caClass: { dimensions: 2, states: 2 },
      settings: {},
      params: {}
    }).cells).toEqual([[1, 1, 0]])
  })

  it('rejects duplicate runtime ids and missing implementations', () => {
    expect(() =>
      registerInitialConditionRuntime({
        id: 'random-soup',
        label: 'Duplicate random soup',
        generate: () => ({ type: 'cells', cells: [], generator: { kind: 'random-soup' } })
      })
    ).toThrow('already registered')

    expect(() =>
      generateInitialCondition('missing-generator', {
        caClass: { dimensions: 2, states: 2 },
        settings: {},
        params: {}
      })
    ).toThrow('unavailable')
  })
})