/* eslint-env mocha */

import { expect } from 'aegir/chai'
import sinon from 'sinon'
import { FetchService, FetchServiceInit } from '../../src/fetch/index.js'
import Peers from '../fixtures/peers.js'
import { mockRegistrar, mockUpgrader, connectionPair } from '@libp2p/interface-mocks'
import { createFromJSON } from '@libp2p/peer-id-factory'
import { Components } from '@libp2p/components'
import { DefaultConnectionManager } from '../../src/connection-manager/index.js'
import { start, stop } from '@libp2p/interfaces/startable'
import { CustomEvent } from '@libp2p/interfaces/events'
import { TimeoutController } from 'timeout-abort-controller'
import delay from 'delay'
import { pipe } from 'it-pipe'
import { PersistentPeerStore } from '@libp2p/peer-store'
import { MemoryDatastore } from 'datastore-core'

const defaultInit: FetchServiceInit = {
  protocolPrefix: 'ipfs',
  maxInboundStreams: 1,
  maxOutboundStreams: 1,
  timeout: 1000
}

async function createComponents (index: number) {
  const peerId = await createFromJSON(Peers[index])

  const components = new Components({
    peerId,
    registrar: mockRegistrar(),
    upgrader: mockUpgrader(),
    peerStore: new PersistentPeerStore(),
    datastore: new MemoryDatastore(),
    connectionManager: new DefaultConnectionManager({
      minConnections: 50,
      maxConnections: 1000,
      autoDialInterval: 1000,
      inboundUpgradeTimeout: 1000
    })
  })

  return components
}

describe('fetch', () => {
  let localComponents: Components
  let remoteComponents: Components

  beforeEach(async () => {
    localComponents = await createComponents(0)
    remoteComponents = await createComponents(1)

    await Promise.all([
      start(localComponents),
      start(remoteComponents)
    ])
  })

  afterEach(async () => {
    sinon.restore()

    await Promise.all([
      stop(localComponents),
      stop(remoteComponents)
    ])
  })

  it('should be able to fetch from another peer', async () => {
    const key = 'key'
    const value = Uint8Array.from([0, 1, 2, 3, 4])
    const localFetch = new FetchService(localComponents, defaultInit)
    const remoteFetch = new FetchService(remoteComponents, defaultInit)

    remoteFetch.registerLookupFunction(key, async (identifier) => {
      expect(identifier).to.equal(key)

      return value
    })

    await start(localFetch)
    await start(remoteFetch)

    // simulate connection between nodes
    const [localToRemote, remoteToLocal] = connectionPair(localComponents, remoteComponents)
    localComponents.getUpgrader().dispatchEvent(new CustomEvent('connection', { detail: localToRemote }))
    remoteComponents.getUpgrader().dispatchEvent(new CustomEvent('connection', { detail: remoteToLocal }))

    // Run fetch
    const result = await localFetch.fetch(remoteComponents.getPeerId(), key)

    expect(result).to.equalBytes(value)
  })

  it('should time out fetching from another peer when waiting for the record', async () => {
    const key = 'key'
    const localFetch = new FetchService(localComponents, defaultInit)
    const remoteFetch = new FetchService(remoteComponents, defaultInit)

    await start(localFetch)
    await start(remoteFetch)

    // simulate connection between nodes
    const [localToRemote, remoteToLocal] = connectionPair(localComponents, remoteComponents)
    localComponents.getUpgrader().dispatchEvent(new CustomEvent('connection', { detail: localToRemote }))
    remoteComponents.getUpgrader().dispatchEvent(new CustomEvent('connection', { detail: remoteToLocal }))

    // replace existing handler with a really slow one
    await remoteComponents.getRegistrar().unhandle(remoteFetch.protocol)
    await remoteComponents.getRegistrar().handle(remoteFetch.protocol, ({ stream }) => {
      void pipe(
        stream,
        async function * (source) {
          for await (const chunk of source) {
            // longer than the timeout
            await delay(1000)

            yield chunk
          }
        },
        stream
      )
    })

    const newStreamSpy = sinon.spy(localToRemote, 'newStream')

    // 10 ms timeout
    const timeoutController = new TimeoutController(10)

    // Run fetch, should time out
    await expect(localFetch.fetch(remoteComponents.getPeerId(), key, {
      signal: timeoutController.signal
    }))
      .to.eventually.be.rejected.with.property('code', 'ABORT_ERR')

    // should have closed stream
    expect(newStreamSpy).to.have.property('callCount', 1)
    const stream = await newStreamSpy.getCall(0).returnValue
    expect(stream).to.have.nested.property('stat.timeline.close')
  })
})