import { mergeMeasurements } from '../src/sync/syncService'
import { Measurement } from '../src/types'

jest.mock('expo-sqlite', () => ({ openDatabaseAsync: jest.fn() }))

const make = (overrides: Partial<Measurement> = {}): Measurement => ({
  id: 'id-1', weight: 75, bmi: 22, bodyFatPercentage: 15, fatMass: 10,
  musclePercentage: 40, muscleMass: 30, visceralFat: 8, bmr: 1600,
  measuredAt: '2024-06-01T08:00:00.000Z', createdAt: '2024-06-01T08:00:00.000Z',
  updatedAt: '2024-06-01T08:00:00.000Z', syncStatus: 'synced', ...overrides,
})

describe('mergeMeasurements', () => {
  it('both empty returns empty', () => {
    expect(mergeMeasurements([], [])).toEqual([])
  })

  it('local only kept', () => {
    const r = mergeMeasurements([make()], [])
    expect(r).toHaveLength(1)
  })

  it('remote only kept', () => {
    const r = mergeMeasurements([], [make({ id: 'r1' })])
    expect(r).toHaveLength(1)
    expect(r[0].id).toBe('r1')
  })

  it('last-writer-wins: remote newer', () => {
    const local = make({ weight: 75, updatedAt: '2024-06-02T08:00:00.000Z' })
    const remote = make({ weight: 76, updatedAt: '2024-06-03T08:00:00.000Z' })
    const r = mergeMeasurements([local], [remote])
    expect(r[0].weight).toBe(76)
  })

  it('last-writer-wins: local newer', () => {
    const local = make({ weight: 77, updatedAt: '2024-06-04T08:00:00.000Z' })
    const remote = make({ weight: 76, updatedAt: '2024-06-03T08:00:00.000Z' })
    const r = mergeMeasurements([local], [remote])
    expect(r[0].weight).toBe(77)
  })

  it('remote deleted wins over synced local', () => {
    const local = make({ updatedAt: '2024-06-01T08:00:00.000Z' })
    const remote: any = { ...make({ updatedAt: '2024-06-03T08:00:00.000Z' }), deleted: true }
    const r = mergeMeasurements([local], [remote])
    expect(r[0].deletedAt).toBe('2024-06-03T08:00:00.000Z')
  })

  it('local synced wins over older remote deleted', () => {
    const local = make({ updatedAt: '2024-06-03T08:00:00.000Z' })
    const remote: any = { ...make({ updatedAt: '2024-06-01T08:00:00.000Z' }), deleted: true }
    const r = mergeMeasurements([local], [remote])
    expect(r[0].deletedAt).toBeUndefined()
  })

  it('local pending-delete wins over remote deleted', () => {
    const local = make({ updatedAt: '2024-06-01T08:00:00.000Z', syncStatus: 'pending-delete', deletedAt: '2024-06-05T08:00:00.000Z' })
    const remote: any = { ...make({ updatedAt: '2024-06-03T08:00:00.000Z' }), deleted: true }
    const r = mergeMeasurements([local], [remote])
    expect(r[0].syncStatus).toBe('pending-delete')
    expect(r[0].deletedAt).toBe('2024-06-05T08:00:00.000Z')
  })

  it('local pending wins over remote newer', () => {
    const local = make({ weight: 75, updatedAt: '2024-06-01T08:00:00.000Z', syncStatus: 'pending' })
    const remote: any = { ...make({ weight: 76, updatedAt: '2024-06-03T08:00:00.000Z' }) }
    const r = mergeMeasurements([local], [remote])
    expect(r[0].weight).toBe(75)
    expect(r[0].syncStatus).toBe('pending')
  })

  it('remote deleted with no local record is skipped', () => {
    const remote: any = { ...make({ id: 'r1', updatedAt: '2024-06-03T08:00:00.000Z' }), deleted: true }
    const r = mergeMeasurements([], [remote])
    expect(r).toHaveLength(0)
  })

  it('local without syncStatus treated as synced', () => {
    const local = make({ weight: 75, updatedAt: '2024-06-01T08:00:00.000Z' })
    delete local.syncStatus
    const remote = make({ weight: 76, updatedAt: '2024-06-03T08:00:00.000Z' })
    const r = mergeMeasurements([local], [remote])
    expect(r[0].weight).toBe(76)
  })
})