import { describe, expect, it } from 'vitest'
import type { SurfaceSnapshot } from '../src/contracts'
import { mergeSurfacesByRevision, surfaceKey } from '../src/surfaceKey'

function snap(id: string, revision: number): SurfaceSnapshot {
  return {
    identity: {
      surfaceId: id,
      owner: 'o',
      pluginId: 'p',
    },
    compat: { schemaVersion: 1, catalogVersion: '1' },
    revision,
    activationEpoch: 0,
    spec: { title: id, nodes: [] },
  }
}

describe('surfaceKey', () => {
  it('reads nested identity and skips missing', () => {
    expect(surfaceKey(snap('s1', 1))).toBe('s1')
    expect(surfaceKey(undefined)).toBeNull()
    expect(surfaceKey({} as SurfaceSnapshot)).toBeNull()
    expect(surfaceKey({ identity: {} } as SurfaceSnapshot)).toBeNull()
  })
})

describe('mergeSurfacesByRevision', () => {
  it('keeps higher revision and drops dirty entries', () => {
    const dirty = { revision: 99 } as SurfaceSnapshot
    const merged = mergeSurfacesByRevision(
      [snap('a', 1), dirty],
      [snap('a', 3), snap('b', 1)],
    )
    expect(merged.map(s => [surfaceKey(s), s.revision])).toEqual([
      ['a', 3],
      ['b', 1],
    ])
  })
})