import { createElement } from 'react'
import { act, create, type ReactTestRenderer } from 'react-test-renderer'
import { afterEach, describe, expect, it, vi } from 'vitest'
import { MobileFileExplorerPanel } from './MobileFileExplorerPanel'
import type { MobileDirEntry } from './file-tree'
import type { RpcResponse } from '../transport/types'

type MockClient = {
  sendRequest: ReturnType<typeof vi.fn>
}

const mockTransport = vi.hoisted(() => ({
  client: null as MockClient | null,
  connectionState: 'connected',
  forceReconnect: vi.fn()
}))

vi.mock('react-native', async () => {
  const React = await import('react')
  return {
    ActivityIndicator: 'ActivityIndicator',
    FlatList: (props: {
      data: unknown[]
      keyExtractor: (item: unknown, index: number) => string
      renderItem: (info: {
        item: unknown
        index: number
        separators: Record<string, never>
      }) => unknown
    }) =>
      React.createElement(
        'FlatList',
        props,
        props.data.map((item, index) =>
          React.createElement(
            'FlatListItem',
            { key: props.keyExtractor(item, index) },
            props.renderItem({ item, index, separators: {} })
          )
        )
      ),
    Pressable: 'Pressable',
    StyleSheet: {
      create: (styles: unknown) => styles,
      hairlineWidth: 1
    },
    Text: 'Text',
    View: 'View'
  }
})

vi.mock('react-native-safe-area-context', () => ({
  SafeAreaView: 'SafeAreaView'
}))

vi.mock('expo-router', () => ({
  useRouter: () => ({
    back: vi.fn(),
    push: vi.fn()
  })
}))

vi.mock('lucide-react-native', () => ({
  ChevronDown: 'ChevronDown',
  ChevronLeft: 'ChevronLeft',
  ChevronRight: 'ChevronRight',
  File: 'File',
  FileText: 'FileText',
  Folder: 'Folder',
  Image: 'Image',
  X: 'X'
}))

vi.mock('../platform/haptics', () => ({
  triggerSelection: vi.fn()
}))

vi.mock('../transport/client-context', () => ({
  useForceReconnect: () => mockTransport.forceReconnect,
  useHostClient: () => ({
    client: mockTransport.client,
    state: mockTransport.connectionState
  })
}))

function suppressReactTestRendererDeprecationWarning(): () => void {
  const originalConsoleError = console.error
  const consoleErrorSpy = vi.spyOn(console, 'error').mockImplementation((...args) => {
    const firstArg = args[0]
    if (typeof firstArg === 'string' && firstArg.includes('react-test-renderer is deprecated')) {
      return
    }
    originalConsoleError(...args)
  })
  return () => consoleErrorSpy.mockRestore()
}

function entry(name: string, isDirectory = false): MobileDirEntry {
  return { name, isDirectory }
}

function ok(result: MobileDirEntry[]): RpcResponse {
  return { id: 'response-id', ok: true, result, _meta: { runtimeId: 'runtime-id' } }
}

function createMockClient(entriesByPath: Record<string, MobileDirEntry[]>): MockClient {
  return {
    sendRequest: vi.fn(async (_method: string, params: { relativePath: string }) => {
      return ok(entriesByPath[params.relativePath] ?? [])
    })
  }
}

async function renderExplorer(): Promise<ReactTestRenderer> {
  let renderer: ReactTestRenderer | null = null
  const restoreConsoleError = suppressReactTestRendererDeprecationWarning()
  try {
    await act(async () => {
      renderer = create(
        createElement(MobileFileExplorerPanel, {
          hostId: 'host-a',
          worktreeId: 'worktree-a',
          name: 'Example Worktree',
          embedded: true
        })
      )
    })
  } finally {
    restoreConsoleError()
  }
  if (!renderer) {
    throw new Error('MobileFileExplorerPanel did not render')
  }
  return renderer
}

async function updateExplorer(renderer: ReactTestRenderer): Promise<void> {
  await act(async () => {
    renderer.update(
      createElement(MobileFileExplorerPanel, {
        hostId: 'host-a',
        worktreeId: 'worktree-a',
        name: 'Example Worktree',
        embedded: true
      })
    )
  })
}

async function pressByLabel(
  renderer: ReactTestRenderer,
  accessibilityLabel: string
): Promise<void> {
  const pressable = renderer.root
    .findAllByType('Pressable')
    .find((node) => node.props.accessibilityLabel === accessibilityLabel)
  if (!pressable) {
    throw new Error(`Unable to find pressable: ${accessibilityLabel}`)
  }
  await act(async () => {
    pressable.props.onPress()
  })
}

function renderedText(renderer: ReactTestRenderer): string {
  return renderer.root
    .findAllByType('Text')
    .flatMap((node) => node.props.children)
    .join(' ')
}

describe('MobileFileExplorerPanel', () => {
  afterEach(() => {
    vi.restoreAllMocks()
    mockTransport.client = null
    mockTransport.connectionState = 'connected'
    mockTransport.forceReconnect = vi.fn()
  })

  it('loads directories lazily and reuses cached children when reopened', async () => {
    const client = createMockClient({
      '': [entry('src', true), entry('README.md')],
      src: [entry('app.ts'), entry('components', true)]
    })
    mockTransport.client = client

    const renderer = await renderExplorer()

    expect(client.sendRequest).toHaveBeenCalledTimes(1)
    expect(client.sendRequest).toHaveBeenLastCalledWith('files.readDir', {
      worktree: 'id:worktree-a',
      relativePath: ''
    })

    await pressByLabel(renderer, 'Open folder src')
    await vi.waitFor(() => expect(client.sendRequest).toHaveBeenCalledTimes(2))
    expect(client.sendRequest).toHaveBeenLastCalledWith('files.readDir', {
      worktree: 'id:worktree-a',
      relativePath: 'src'
    })
    expect(renderedText(renderer)).toContain('app.ts')

    await pressByLabel(renderer, 'Open folder src')
    await pressByLabel(renderer, 'Open folder src')

    expect(client.sendRequest).toHaveBeenCalledTimes(2)
  })

  it('keeps the loaded tree visible during a transient disconnect', async () => {
    const client = createMockClient({
      '': [entry('src', true), entry('README.md')]
    })
    mockTransport.client = client

    const renderer = await renderExplorer()
    expect(renderedText(renderer)).toContain('src')

    mockTransport.client = null
    mockTransport.connectionState = 'disconnected'
    await updateExplorer(renderer)

    expect(client.sendRequest).toHaveBeenCalledTimes(1)
    expect(renderedText(renderer)).toContain('src')
    expect(renderedText(renderer)).toContain('README.md')
    expect(renderedText(renderer)).not.toContain('Waiting for desktop...')
  })

  it('refreshes the root in the background after reconnect without blanking the tree', async () => {
    const client = createMockClient({
      '': [entry('src', true), entry('README.md')]
    })
    mockTransport.client = client

    const renderer = await renderExplorer()
    expect(renderedText(renderer)).toContain('README.md')

    mockTransport.client = null
    mockTransport.connectionState = 'disconnected'
    await updateExplorer(renderer)

    let resolveReload: ((response: RpcResponse) => void) | undefined
    const reconnectedClient: MockClient = {
      sendRequest: vi.fn(
        () =>
          new Promise<RpcResponse>((resolve) => {
            resolveReload = resolve
          })
      )
    }
    mockTransport.client = reconnectedClient
    mockTransport.connectionState = 'connected'
    await updateExplorer(renderer)

    expect(reconnectedClient.sendRequest).toHaveBeenCalledTimes(1)
    expect(renderedText(renderer)).toContain('src')
    expect(renderedText(renderer)).toContain('README.md')

    await act(async () => {
      resolveReload?.(ok([entry('src', true), entry('README.md'), entry('CHANGELOG.md')]))
    })
    expect(renderedText(renderer)).toContain('CHANGELOG.md')
  })

  it('keeps the cached tree when a post-reconnect root refresh fails', async () => {
    const client = createMockClient({
      '': [entry('src', true), entry('README.md')]
    })
    mockTransport.client = client

    const renderer = await renderExplorer()
    expect(renderedText(renderer)).toContain('README.md')

    mockTransport.client = null
    mockTransport.connectionState = 'disconnected'
    await updateExplorer(renderer)

    const failingClient: MockClient = {
      sendRequest: vi.fn(async () => {
        throw new Error('refresh failed')
      })
    }
    mockTransport.client = failingClient
    mockTransport.connectionState = 'connected'
    await updateExplorer(renderer)

    expect(failingClient.sendRequest).toHaveBeenCalledTimes(1)
    expect(renderedText(renderer)).toContain('src')
    expect(renderedText(renderer)).toContain('README.md')
    expect(renderedText(renderer)).not.toContain('refresh failed')
  })

  it('falls back to the capped files.list against desktops without files.readDir', async () => {
    const legacyClient: MockClient = {
      sendRequest: vi.fn(async (method: string): Promise<RpcResponse> => {
        if (method === 'files.readDir') {
          return {
            id: 'response-id',
            ok: false,
            error: {
              code: 'forbidden',
              message: "Method 'files.readDir' is not available to mobile clients"
            },
            _meta: { runtimeId: 'runtime-id' }
          }
        }
        return {
          id: 'response-id',
          ok: true,
          result: {
            files: [
              { relativePath: 'src/app.ts', basename: 'app.ts', kind: 'text' },
              { relativePath: 'README.md', basename: 'README.md', kind: 'text' }
            ],
            totalCount: 2,
            truncated: false
          },
          _meta: { runtimeId: 'runtime-id' }
        }
      })
    }
    mockTransport.client = legacyClient

    const renderer = await renderExplorer()

    expect(legacyClient.sendRequest).toHaveBeenCalledWith('files.list', {
      worktree: 'id:worktree-a'
    })
    expect(renderedText(renderer)).toContain('src')
    expect(renderedText(renderer)).toContain('README.md')

    await pressByLabel(renderer, 'Open folder src')
    expect(renderedText(renderer)).toContain('app.ts')
    // Every directory comes from the synthesized cache: one readDir attempt
    // plus one files.list call total, no per-directory RPCs afterwards.
    expect(legacyClient.sendRequest).toHaveBeenCalledTimes(2)
  })

  it('surfaces the legacy cap note when the files.list fallback is truncated', async () => {
    const legacyClient: MockClient = {
      sendRequest: vi.fn(async (method: string): Promise<RpcResponse> => {
        if (method === 'files.readDir') {
          return {
            id: 'response-id',
            ok: false,
            error: { code: 'method_not_found', message: 'Unknown method' },
            _meta: { runtimeId: 'runtime-id' }
          }
        }
        return {
          id: 'response-id',
          ok: true,
          result: {
            files: [{ relativePath: 'README.md', basename: 'README.md', kind: 'text' }],
            totalCount: 6000,
            truncated: true
          },
          _meta: { runtimeId: 'runtime-id' }
        }
      })
    }
    mockTransport.client = legacyClient

    const renderer = await renderExplorer()

    expect(renderedText(renderer)).toContain('README.md')
    expect(renderedText(renderer)).toContain('Showing first 5000')
  })

  it('reports the files.list failure when the fallback itself fails', async () => {
    const legacyClient: MockClient = {
      sendRequest: vi.fn(async (method: string): Promise<RpcResponse> => {
        if (method === 'files.readDir') {
          return {
            id: 'response-id',
            ok: false,
            error: {
              code: 'forbidden',
              message: "Method 'files.readDir' is not available to mobile clients"
            },
            _meta: { runtimeId: 'runtime-id' }
          }
        }
        return {
          id: 'response-id',
          ok: false,
          error: { code: 'internal', message: 'legacy list failed' },
          _meta: { runtimeId: 'runtime-id' }
        }
      })
    }
    mockTransport.client = legacyClient

    const renderer = await renderExplorer()

    expect(renderedText(renderer)).toContain('legacy list failed')
    expect(renderedText(renderer)).not.toContain('not available to mobile clients')
  })
})