import { describe, expect, it } from 'vitest'

import { resolveConversationParticipant } from './resolveConversationParticipant'

const OFFICIAL_SENDER_USER_ID = 'linktree-official-sender'

const members = {
  [OFFICIAL_SENDER_USER_ID]: {
    user: { id: OFFICIAL_SENDER_USER_ID, name: 'Linktree' },
  },
  'account-uuid': { user: { id: 'account-uuid', name: 'Jane Linker' } },
} as never

describe('resolveConversationParticipant', () => {
  it('returns the member that is not the current user for a normal channel', () => {
    const participant = resolveConversationParticipant(
      members,
      'account-uuid',
      'messaging'
    )
    expect(participant?.user?.id).toBe(OFFICIAL_SENDER_USER_ID)
  })

  it('returns the official sender for the official channel when the linker views it (member)', () => {
    const participant = resolveConversationParticipant(
      members,
      'account-uuid',
      'linktree-official'
    )
    expect(participant?.user?.name).toBe('Linktree')
  })

  it('returns the official sender for the official channel when a guest views it (non-member)', () => {
    // A guest's random Stream id isn't a member, so the "not me" heuristic
    // would otherwise fall back to the linker's member and show their name.
    const participant = resolveConversationParticipant(
      members,
      'guest-random-uuid-account-uuid',
      'linktree-official'
    )
    expect(participant?.user?.name).toBe('Linktree')
  })

  it('falls back to the non-current member when the official sender is absent', () => {
    const withoutSender = {
      'account-uuid': { user: { id: 'account-uuid', name: 'Jane Linker' } },
    } as never
    const participant = resolveConversationParticipant(
      withoutSender,
      'guest-random-uuid',
      'linktree-official'
    )
    expect(participant?.user?.id).toBe('account-uuid')
  })

  it('returns undefined when there are no members', () => {
    expect(
      resolveConversationParticipant(undefined, 'account-uuid', 'messaging')
    ).toBeUndefined()
  })
})