/**
 * Git worktree selection is an atomic view boundary: status, branch choices
 * and history must always come from the same checkout. A stale history row is
 * especially dangerous because its revert/cherry-pick action targets the
 * currently selected checkout.
 *
 * The status itself now comes from the shared git-status store (one snapshot
 * per session+cwd+worktree, one poller), so these tests observe the selection
 * through the rows it renders and through the scope each git call receives —
 * including the `repoRoot` a container's worktree listing must carry.
 */
// @vitest-environment jsdom
import { afterEach, describe, expect, it, vi } from 'vitest'
import { createElement } from 'react'
import { createRoot, type Root } from 'react-dom/client'
import { act } from 'react-dom/test-utils'
import { GitLens } from '../src/client/changes/GitLens.tsx'
import { createSidebarStore } from '../src/client/state.ts'
import { api, type GitLogEntry, type GitStatusResult, type GitWorktree } from '../src/client/api.ts'
import { t } from '../src/client/locales.ts'

import { setupReactAct } from './test-utils.ts'
setupReactAct()

const MAIN = 'C:/repo/main'
const AGENT = 'C:/repo/agent'
/** A second linked checkout some tests introduce on a later inventory pass. */
const AGENT_2 = 'C:/repo/agent-2'

const inventories: GitWorktree[] = [
  { path: MAIN, branch: 'main', current: true, changes: 0 },
  { path: AGENT, branch: 'agent', current: false, changes: 1 },
]

function statusFor(target?: string): GitStatusResult {
  if (target === AGENT_2) return { isRepo: true, branch: 'agent-2', entries: [{ path: 'agent-2-change.ts', xy: ' M' }] }
  return target === AGENT
    ? { isRepo: true, branch: 'agent', entries: [{ path: 'agent-change.ts', xy: ' M' }] }
    : { isRepo: true, branch: 'main', entries: [{ path: 'main-change.ts', xy: ' M' }] }
}

function logFor(target?: string, index = 0): GitLogEntry[] {
  const agent = target === AGENT
  const digit = agent ? 'a' : 'b'
  const suffix = index.toString(16).padStart(8, '0')
  return [{
    hash: `${digit.repeat(6)}${suffix.slice(-1)}`,
    hashFull: `${digit.repeat(32)}${suffix}`,
    subject: agent ? `Agent checkout commit ${index}` : `Main checkout commit ${index}`,
    author: 'Test',
    date: '2026-08-20 00:00:00 +0800',
    refs: agent ? 'HEAD -> agent' : 'HEAD -> main',
  }]
}

function deferred<T>(): { promise: Promise<T>; resolve: (value: T) => void } {
  let resolvePromise!: (value: T) => void
  const promise = new Promise<T>((resolve) => { resolvePromise = resolve })
  return { promise, resolve: resolvePromise }
}

async function flushEffects(): Promise<void> {
  // Each round drains one promise hop: the refresh chain (listing → branch/log
  // → state) is several hops deep, and a shallow flush would assert on rows
  // that are still in flight.
  for (let round = 0; round < 5; round += 1) await act(async () => { await Promise.resolve() })
}

/** Mount one GitLens. Visible by default: a hidden tab owns no live git data
 *  — the shared status store only polls/loads while a consumer is on screen. */
function mountGit(
  root: Root,
  options: { scope?: { sessionId: string; cwd?: string }; refreshTick?: number; visible?: boolean } = {},
): void {
  act(() => {
    root.render(createElement(GitLens, {
      scope: options.scope ?? { sessionId: 'session', cwd: MAIN },
      store: createSidebarStore(),
      onOpenFile: () => {},
      onPreview: () => {},
      selectedRef: null,
      visible: options.visible ?? true,
      refreshTick: options.refreshTick ?? 0,
    }))
  })
}

afterEach(() => { vi.restoreAllMocks() })

describe('GitLens (changes tab, git lens) linked-worktree consistency', () => {
  it('refreshes status, branches and history together on auto and manual selection', async () => {
    vi.spyOn(api, 'gitWorktrees').mockResolvedValue(inventories)
    vi.spyOn(api, 'gitStatus').mockImplementation(async (_scope, target) => statusFor(target))
    const branch = vi.spyOn(api, 'gitBranch').mockImplementation(async (_scope, target) => ({
      current: target === AGENT ? 'agent' : 'main',
      names: target === AGENT ? ['agent'] : ['main'],
    }))
    const log = vi.spyOn(api, 'gitLog').mockImplementation(async (_scope, _count, _skip, target) => logFor(target))

    const container = document.createElement('div')
    document.body.append(container)
    const root: Root = createRoot(container)
    try {
      mountGit(root)
      await flushEffects()

      const selects = container.querySelectorAll<HTMLSelectElement>('select')
      const worktreeSelect = selects[0]!
      // A clean primary + exactly one dirty linked checkout auto-selects the
      // linked checkout and loads every target-derived surface from it.
      expect(worktreeSelect.value).toBe(AGENT)
      expect(container.textContent).toContain('agent-change.ts')
      expect(container.textContent).toContain('Agent checkout commit')
      expect(container.textContent).not.toContain('Main checkout commit')
      expect(branch).toHaveBeenCalledWith(expect.anything(), AGENT)
      expect(log).toHaveBeenCalledWith(expect.anything(), 20, 0, AGENT)

      await act(async () => {
        Object.getOwnPropertyDescriptor(HTMLSelectElement.prototype, 'value')!.set!.call(worktreeSelect, MAIN)
        worktreeSelect.dispatchEvent(new Event('change', { bubbles: true }))
      })
      await flushEffects()

      expect(worktreeSelect.value).toBe(MAIN)
      expect(container.textContent).toContain('main-change.ts')
      expect(container.textContent).toContain('Main checkout commit')
      expect(container.textContent).not.toContain('Agent checkout commit')
      expect(branch).toHaveBeenLastCalledWith(expect.anything(), MAIN)
      expect(log).toHaveBeenLastCalledWith(expect.anything(), 20, 0, MAIN)
    } finally {
      act(() => { root.unmount() })
      container.remove()
    }
  })

  it('drops a late history page when the selected worktree changes', async () => {
    const lateAgentPage = deferred<GitLogEntry[]>()
    vi.spyOn(api, 'gitWorktrees').mockResolvedValue(inventories)
    vi.spyOn(api, 'gitStatus').mockImplementation(async (_scope, target) => statusFor(target))
    vi.spyOn(api, 'gitBranch').mockImplementation(async (_scope, target) => ({
      current: target === AGENT ? 'agent' : 'main',
      names: target === AGENT ? ['agent'] : ['main'],
    }))
    vi.spyOn(api, 'gitLog').mockImplementation(async (_scope, _count, skip, target) => {
      if (target === AGENT && skip === 20) return lateAgentPage.promise
      if (target === AGENT) return Array.from({ length: 20 }, (_value, index) => logFor(AGENT, index)[0]!)
      return logFor(MAIN)
    })

    const container = document.createElement('div')
    document.body.append(container)
    const root: Root = createRoot(container)
    try {
      mountGit(root)
      await flushEffects()

      const worktreeSelect = container.querySelectorAll<HTMLSelectElement>('select')[0]!
      const loadMore = [...container.querySelectorAll<HTMLButtonElement>('button')]
        .find(button => /Load more|加载更多/.test(button.textContent ?? ''))
      expect(loadMore).not.toBeUndefined()
      await act(async () => { loadMore!.click() })

      await act(async () => {
        Object.getOwnPropertyDescriptor(HTMLSelectElement.prototype, 'value')!.set!.call(worktreeSelect, MAIN)
        worktreeSelect.dispatchEvent(new Event('change', { bubbles: true }))
      })
      await flushEffects()
      expect(container.textContent).toContain('Main checkout commit 0')

      lateAgentPage.resolve(logFor(AGENT, 99))
      await flushEffects()
      expect(container.textContent).toContain('Main checkout commit 0')
      expect(container.textContent).not.toContain('Agent checkout commit 99')
    } finally {
      act(() => { root.unmount() })
      container.remove()
    }
  })

  it('lists a selected child repository with its repoRoot, running one full refresh', async () => {
    const WS = 'C:/ws'
    const REPO_A = 'C:/ws/a'
    const REPO_B = 'C:/ws/b'
    const repoBWorktrees: GitWorktree[] = [
      { path: REPO_B, branch: 'b-main', current: true, changes: 0 },
      { path: 'C:/ws/b-agent', branch: 'b-agent', current: false, changes: 2 },
    ]
    const worktrees = vi.spyOn(api, 'gitWorktrees').mockImplementation(async (scope) => (
      scope.repoRoot === REPO_B ? repoBWorktrees : []
    ))
    const status = vi.spyOn(api, 'gitStatus').mockImplementation(async (scope) => (
      scope.cwd === REPO_B
        ? { isRepo: true, branch: 'b-main', entries: [], root: REPO_B, repositories: [REPO_B] }
        : { isRepo: true, branch: 'a-main', entries: [], root: REPO_A, repositories: [REPO_A, REPO_B] }
    ))
    vi.spyOn(api, 'gitBranch').mockImplementation(async (scope) => (
      scope.repoRoot === REPO_B ? { current: 'b-main', names: ['b-main'] } : { current: 'a-main', names: ['a-main'] }
    ))
    vi.spyOn(api, 'gitLog').mockResolvedValue([])

    const container = document.createElement('div')
    document.body.append(container)
    const root: Root = createRoot(container)
    try {
      mountGit(root, { scope: { sessionId: 'session', cwd: WS } })
      await flushEffects()

      // The workspace container's two child repositories are the repo choices.
      const repoSelect = container.querySelectorAll<HTMLSelectElement>('select')[0]!
      expect([...repoSelect.options].map(option => option.textContent)).toEqual(['a', 'b'])
      const listingsBefore = worktrees.mock.calls.length

      await act(async () => {
        Object.getOwnPropertyDescriptor(HTMLSelectElement.prototype, 'value')!.set!.call(repoSelect, REPO_B)
        repoSelect.dispatchEvent(new Event('change', { bubbles: true }))
      })
      await flushEffects()

      // The listing carries the selected repoRoot — a container's own listing
      // is empty, so the child checkout's linked worktrees only appear when the
      // selection rides along.
      expect(worktrees.mock.calls.at(-1)![0]).toMatchObject({ sessionId: 'session', cwd: WS, repoRoot: REPO_B })
      // Exactly ONE full refresh for the switch (not a burst).
      expect(worktrees.mock.calls.length).toBe(listingsBefore + 1)
      // The shared status follows the same selection.
      expect(status.mock.calls.some(([scope]) => scope.cwd === REPO_B)).toBe(true)
      const worktreeSelect = container.querySelectorAll<HTMLSelectElement>('select')[1]!
      expect(worktreeSelect.value).toBe(REPO_B)
    } finally {
      act(() => { root.unmount() })
      container.remove()
    }
  })

  it('never yanks the view off the auto-selected checkout on a later re-list', async () => {
    const LATER: GitWorktree[] = [
      { path: MAIN, branch: 'main', current: true, changes: 0 },
      { path: AGENT, branch: 'agent', current: false, changes: 0 },
      { path: AGENT_2, branch: 'agent-2', current: false, changes: 5 },
    ]
    vi.spyOn(api, 'gitWorktrees')
      .mockResolvedValueOnce(inventories)
      .mockResolvedValue(LATER)
    vi.spyOn(api, 'gitStatus').mockImplementation(async (_scope, target) => statusFor(target))
    vi.spyOn(api, 'gitBranch').mockImplementation(async (_scope, target) => ({
      current: target === AGENT ? 'agent' : 'main',
      names: target === AGENT ? ['agent'] : ['main'],
    }))
    vi.spyOn(api, 'gitLog').mockImplementation(async (_scope, _count, _skip, target) => logFor(target))

    const container = document.createElement('div')
    document.body.append(container)
    const root: Root = createRoot(container)
    try {
      mountGit(root)
      await flushEffects()
      const worktreeSelect = container.querySelectorAll<HTMLSelectElement>('select')[0]!
      expect(worktreeSelect.value).toBe(AGENT)

      // A later inventory pass prefers the brand-new dirty checkout; the user
      // never chose a checkout, but the ONE automatic pass already ran.
      mountGit(root, { refreshTick: 1 })
      await flushEffects()

      expect(worktreeSelect.value).toBe(AGENT)
      expect(container.textContent).toContain('agent-change.ts')
      expect(container.textContent).not.toContain('agent-2-change.ts')
    } finally {
      act(() => { root.unmount() })
      container.remove()
    }
  })

  it('queues a manual refresh that lands while a refresh is in flight', async () => {
    const held = deferred<GitWorktree[]>()
    const worktrees = vi.spyOn(api, 'gitWorktrees')
      .mockReturnValueOnce(held.promise)
      .mockResolvedValue(inventories)
    vi.spyOn(api, 'gitStatus').mockImplementation(async (_scope, target) => statusFor(target))
    vi.spyOn(api, 'gitBranch').mockImplementation(async (_scope, target) => ({
      current: target === AGENT ? 'agent' : 'main',
      names: target === AGENT ? ['agent'] : ['main'],
    }))
    vi.spyOn(api, 'gitLog').mockImplementation(async (_scope, _count, _skip, target) => logFor(target))

    const container = document.createElement('div')
    document.body.append(container)
    const root: Root = createRoot(container)
    try {
      mountGit(root)
      await flushEffects()
      expect(worktrees).toHaveBeenCalledTimes(1)

      // The header's refresh action lands while the mount pass is in flight.
      mountGit(root, { refreshTick: 1 })
      await flushEffects()
      // Queued, not dropped and not started in parallel.
      expect(worktrees).toHaveBeenCalledTimes(1)

      held.resolve([])
      await flushEffects()
      // The queued pass ran and its listing landed: the dirty linked checkout
      // is selected and its rows are the ones on screen.
      expect(worktrees).toHaveBeenCalledTimes(2)
      expect(container.textContent).toContain('agent-change.ts')
    } finally {
      act(() => { root.unmount() })
      container.remove()
    }
  })

  it('stays quiet while hidden and catches up when the tab becomes visible', async () => {
    const worktrees = vi.spyOn(api, 'gitWorktrees').mockResolvedValue(inventories)
    const status = vi.spyOn(api, 'gitStatus').mockImplementation(async (_scope, target) => statusFor(target))
    vi.spyOn(api, 'gitBranch').mockImplementation(async (_scope, target) => ({
      current: target === AGENT ? 'agent' : 'main',
      names: target === AGENT ? ['agent'] : ['main'],
    }))
    vi.spyOn(api, 'gitLog').mockImplementation(async (_scope, _count, _skip, target) => logFor(target))

    const container = document.createElement('div')
    document.body.append(container)
    const root: Root = createRoot(container)
    try {
      // Mounted in a background pane: no fetch at all (no git processes for a
      // tab nobody is looking at).
      mountGit(root, { visible: false })
      await flushEffects()
      expect(worktrees).not.toHaveBeenCalled()
      expect(status).not.toHaveBeenCalled()

      // Bringing the tab on screen loads the lens through one pass.
      mountGit(root, { visible: true })
      await flushEffects()
      expect(worktrees).toHaveBeenCalledTimes(1)
      expect(status).toHaveBeenCalled()
      expect(container.textContent).toContain('agent-change.ts')
      expect(container.textContent).toContain('Agent checkout commit')
    } finally {
      act(() => { root.unmount() })
      container.remove()
    }
  })

  it('hands the inventory poll its AbortSignal and stops it when hidden', async () => {
    vi.useFakeTimers()
    const worktrees = vi.spyOn(api, 'gitWorktrees').mockResolvedValue(inventories)
    vi.spyOn(api, 'gitStatus').mockImplementation(async (_scope, target) => statusFor(target))
    vi.spyOn(api, 'gitBranch').mockImplementation(async (_scope, target) => ({
      current: target === AGENT ? 'agent' : 'main',
      names: target === AGENT ? ['agent'] : ['main'],
    }))
    vi.spyOn(api, 'gitLog').mockImplementation(async (_scope, _count, _skip, target) => logFor(target))

    const container = document.createElement('div')
    document.body.append(container)
    const root: Root = createRoot(container)
    try {
      mountGit(root)
      await flushEffects()
      expect(worktrees).toHaveBeenCalledTimes(1)

      // The 30s inventory cadence fires and carries the poller's signal.
      await act(async () => { await vi.advanceTimersByTimeAsync(30_000) })
      await flushEffects()
      expect(worktrees.mock.calls.length).toBe(2)
      const signal = worktrees.mock.calls[1]![1]
      expect(signal).toBeInstanceOf(AbortSignal)

      // Hiding the tab tears the poll down and aborts its signal: a slow host
      // answer can no longer publish state.
      mountGit(root, { visible: false })
      await flushEffects()
      expect((signal as AbortSignal).aborted).toBe(true)
      const callsWhileHidden = worktrees.mock.calls.length
      await act(async () => { await vi.advanceTimersByTimeAsync(120_000) })
      expect(worktrees.mock.calls.length).toBe(callsWhileHidden)
    } finally {
      act(() => { root.unmount() })
      container.remove()
      vi.useRealTimers()
    }
  })

  it('keeps branch switch and history failures out of the commit bar', async () => {
    vi.spyOn(api, 'gitWorktrees').mockResolvedValue([
      { path: MAIN, branch: 'main', current: true, changes: 1 },
    ])
    vi.spyOn(api, 'gitStatus').mockResolvedValue({
      isRepo: true, branch: 'main', entries: [{ path: 'src/a.ts', xy: ' M' }],
    })
    vi.spyOn(api, 'gitBranch').mockResolvedValue({ current: 'main', names: ['main', 'feature'] })
    vi.spyOn(api, 'gitLog').mockResolvedValue([])
    vi.spyOn(api, 'gitCheckout').mockRejectedValue(new Error('dirty worktree'))

    const container = document.createElement('div')
    document.body.append(container)
    const root: Root = createRoot(container)
    try {
      mountGit(root)
      await flushEffects()

      const branchSelect = container.querySelectorAll<HTMLSelectElement>('select')[0]!
      await act(async () => {
        Object.getOwnPropertyDescriptor(HTMLSelectElement.prototype, 'value')!.set!.call(branchSelect, 'feature')
        branchSelect.dispatchEvent(new Event('change', { bubbles: true }))
      })
      await flushEffects()

      const banner = [...container.querySelectorAll<HTMLElement>('[role="alert"]')]
        .find(node => (node.textContent ?? '').includes(`${t('checkoutError')}: dirty worktree`))
      expect(banner).toBeDefined()
      const input = container.querySelector(`input[placeholder="${t('commitPlaceholder')}"]`)
      expect(input).not.toBeNull()
      // The commit bar owns only its own status line: the branch failure is
      // rendered ABOVE it, never under the commit input.
      expect(banner!.compareDocumentPosition(input!) & Node.DOCUMENT_POSITION_FOLLOWING).toBeTruthy()
    } finally {
      act(() => { root.unmount() })
      container.remove()
    }
  })
})