import { execFileSync } from 'node:child_process'
import { mkdirSync, writeFileSync } from 'node:fs'
import path from 'node:path'
import type { Page } from '@stablyai/playwright-test'
import { expect, test } from './helpers/orca-app'
import { pressShortcut } from './helpers/shortcuts'
import { waitForActiveWorktree, waitForSessionReady } from './helpers/store'

// Exercise real gutter ownership and pointer tracking: the range must survive composer open without starting Monaco selection.

const BAND = '.orca-diff-comment-range-highlight'
const COMPOSER = '.orca-diff-comment-popover'
const COMPOSER_LABEL = '.orca-diff-comment-popover-label'
const COMPOSER_TEXTAREA = '.orca-diff-comment-popover-textarea'

type StoredNote = { startLine?: number; lineNumber: number; body: string }

// Commit a baseline: untracked files open without the diff gutter this gesture needs.
const SEED_BASELINE = 'export const seed = true\n'
const SEED_LINE_COUNT = 24
// Wait for the highest tested line so first-cell paint cannot hide an unloaded modified model.
const SEED_SYNC_LINE = 9

async function seedDiffFile(page: Page, worktreeId: string, relative: string): Promise<void> {
  const { worktreePath, storeRel } = await page.evaluate(
    ({ wId, rel }) => {
      const store = window.__store
      if (!store) {
        throw new Error('window.__store is not available - is the app in dev mode?')
      }
      const worktree = Object.values(store.getState().worktreesByRepo)
        .flat()
        .find((entry) => entry.id === wId)
      if (!worktree) {
        throw new Error('active worktree not found')
      }
      const separator = worktree.path.includes('\\') ? '\\' : '/'
      return { worktreePath: worktree.path, storeRel: rel.split('/').join(separator) }
    },
    { wId: worktreeId, rel: relative }
  )

  // Commit before rewriting, idempotently across reruns on the worker-scoped repo.
  const absolutePath = path.join(worktreePath, ...relative.split('/'))
  mkdirSync(path.dirname(absolutePath), { recursive: true })
  writeFileSync(absolutePath, SEED_BASELINE)
  const porcelain = execFileSync('git', ['status', '--porcelain', '--', relative], {
    cwd: worktreePath,
    encoding: 'utf8'
  })
  if (porcelain.trim() !== '') {
    execFileSync('git', ['add', '--', relative], { cwd: worktreePath, stdio: 'pipe' })
    execFileSync('git', ['commit', '-m', `e2e seed ${relative} for diff-note-range`], {
      cwd: worktreePath,
      stdio: 'pipe'
    })
  }
  const lines = Array.from(
    { length: SEED_LINE_COUNT },
    (_, index) => `export const line${String(index + 1).padStart(2, '0')} = ${index + 1}`
  )
  writeFileSync(absolutePath, `${lines.join('\n')}\n`)

  await page.evaluate(
    async ({ wId, rel }) => {
      const store = window.__store
      if (!store) {
        throw new Error('window.__store is not available - is the app in dev mode?')
      }
      const state = store.getState()
      const worktree = Object.values(state.worktreesByRepo)
        .flat()
        .find((entry) => entry.id === wId)
      if (!worktree) {
        throw new Error('active worktree not found')
      }
      const separator = worktree.path.includes('\\') ? '\\' : '/'
      // Inline view keeps modified line numbers in the gesture’s margin.
      await state.updateSettings({ diffDefaultView: 'inline' })
      state.openDiff(wId, `${worktree.path}${separator}${rel}`, rel, 'typescript', false)
    },
    { wId: worktreeId, rel: storeRel }
  )
  await expect(
    page.locator('.modified-in-monaco-diff-editor .margin .line-numbers').first(),
    'diff gutter never rendered'
  ).toBeVisible({ timeout: 20_000 })
  await expect
    .poll(async () => hasGutterLine(page, SEED_SYNC_LINE), {
      timeout: 20_000,
      message: 'modified diff content never rendered its gutter lines'
    })
    .toBe(true)
}

async function readGutterPoint(
  page: Page,
  lineNumber: number
): Promise<{ x: number; y: number } | null> {
  return page.evaluate((target: number) => {
    const editor = document.querySelector('.monaco-editor.modified-in-monaco-diff-editor')
    if (!editor) {
      return null
    }
    for (const cell of editor.querySelectorAll('.margin .line-numbers')) {
      if (Number.parseInt(cell.textContent?.trim() ?? '', 10) === target) {
        const rect = cell.getBoundingClientRect()
        return { x: Math.round(rect.x + rect.width / 2), y: Math.round(rect.y + rect.height / 2) }
      }
    }
    return null
  }, lineNumber)
}

async function hasGutterLine(page: Page, lineNumber: number): Promise<boolean> {
  return (await readGutterPoint(page, lineNumber)) !== null
}

// Centre of a line's number cell — the column the "+" lives in and the gesture starts from.
async function gutterPoint(page: Page, lineNumber: number): Promise<{ x: number; y: number }> {
  let point: { x: number; y: number } | null = null
  await expect
    .poll(
      async () => {
        point = await readGutterPoint(page, lineNumber)
        return point
      },
      {
        timeout: 20_000,
        message: `line ${lineNumber} is not rendered in the modified gutter`
      }
    )
    .not.toBeNull()
  if (point == null) {
    throw new Error(`line ${lineNumber} is not rendered in the modified gutter`)
  }
  return point
}

// Box of the "+" affordance, which only exists while its line is hovered.
async function revealAddButton(
  page: Page,
  lineNumber: number
): Promise<{ x: number; y: number; top: string }> {
  const line = await gutterPoint(page, lineNumber)
  await page.mouse.move(line.x + 260, line.y)
  const button = page.locator('.orca-diff-comment-add-btn')
  await expect(button, 'the "+" never appeared on the hovered line').toBeVisible()
  const box = await button.boundingBox()
  if (!box) {
    throw new Error('the "+" has no box')
  }
  const top = await button.evaluate((node) => {
    if (!(node instanceof HTMLElement)) {
      throw new Error('the add button is not an HTMLElement')
    }
    return node.style.top
  })
  return {
    x: Math.round(box.x + box.width / 2),
    y: Math.round(box.y + box.height / 2),
    top
  }
}

async function readNotes(page: Page, worktreeId: string): Promise<StoredNote[]> {
  return page.evaluate((wId: string) => {
    const worktree = Object.values(window.__store?.getState().worktreesByRepo ?? {})
      .flat()
      .find((entry) => entry.id === wId)
    return (worktree?.diffComments ?? []).map((comment) => ({
      startLine: comment.startLine,
      lineNumber: comment.lineNumber,
      body: comment.body
    }))
  }, worktreeId)
}

async function submitNote(page: Page, body: string): Promise<void> {
  await page.locator(COMPOSER_TEXTAREA).fill(body)
  await page.keyboard.press('Enter')
  await expect(page.locator(COMPOSER), 'composer stayed open after submit').toHaveCount(0, {
    timeout: 10_000
  })
}

test.describe('Diff note line range', () => {
  test.beforeEach(async ({ orcaPage }) => {
    await waitForSessionReady(orcaPage)
    await waitForActiveWorktree(orcaPage)
  })

  test('dragging the gutter selects a range, keeps it lit, and saves one ranged note', async ({
    orcaPage
  }) => {
    const worktreeId = await waitForActiveWorktree(orcaPage)
    await seedDiffFile(orcaPage, worktreeId, 'src/diff-note-range-drag.ts')

    const from = await gutterPoint(orcaPage, 4)
    const to = await gutterPoint(orcaPage, 9)

    await orcaPage.mouse.move(from.x, from.y)
    await orcaPage.mouse.down()
    await expect(orcaPage.locator(BAND)).toHaveCount(1)

    await orcaPage.mouse.move(to.x, (from.y + to.y) / 2)
    await orcaPage.mouse.move(to.x, to.y)
    await expect(
      orcaPage.locator(BAND),
      'the band did not follow the pointer while the button was held'
    ).toHaveCount(6)

    await orcaPage.mouse.up()

    await expect(orcaPage.locator(COMPOSER_LABEL)).toHaveText('Lines 4-9')
    await expect(
      orcaPage.locator(BAND),
      'the band should stay lit while the note is being written'
    ).toHaveCount(6)
    // The gutter press belongs to us, so Monaco never started a text selection under it.
    expect(await orcaPage.evaluate(() => window.getSelection()?.toString() ?? '')).toBe('')

    await submitNote(orcaPage, 'Collapse these six lines into a loop.')

    expect(await readNotes(orcaPage, worktreeId)).toEqual([
      { startLine: 4, lineNumber: 9, body: 'Collapse these six lines into a loop.' }
    ])
    const card = orcaPage.locator('.orca-diff-comment-card').first()
    await expect(card, 'saved note card did not render').toBeVisible({ timeout: 15_000 })
    await expect(card).toContainText('lines 4-9')
    await expect(orcaPage.locator(BAND)).toHaveCount(0)
  })

  // Drag upward to prove anchor/focus stay distinct and commit in document order.
  test('dragging the gutter upward commits the same range as dragging down', async ({
    orcaPage
  }) => {
    const worktreeId = await waitForActiveWorktree(orcaPage)
    await seedDiffFile(orcaPage, worktreeId, 'src/diff-note-range-drag-up.ts')

    const from = await gutterPoint(orcaPage, 9)
    const to = await gutterPoint(orcaPage, 4)

    await orcaPage.mouse.move(from.x, from.y)
    await orcaPage.mouse.down()
    await expect(orcaPage.locator(BAND)).toHaveCount(1)

    await orcaPage.mouse.move(to.x, (from.y + to.y) / 2)
    await orcaPage.mouse.move(to.x, to.y)
    await expect(
      orcaPage.locator(BAND),
      'the band did not grow upward while the button was held'
    ).toHaveCount(6)

    await orcaPage.mouse.up()

    await expect(orcaPage.locator(COMPOSER_LABEL)).toHaveText('Lines 4-9')
    expect(await orcaPage.evaluate(() => window.getSelection()?.toString() ?? '')).toBe('')

    await submitNote(orcaPage, 'Dragged bottom to top.')

    expect(await readNotes(orcaPage, worktreeId)).toEqual([
      { startLine: 4, lineNumber: 9, body: 'Dragged bottom to top.' }
    ])
    await expect(orcaPage.locator('.orca-diff-comment-card').first()).toContainText('lines 4-9')
  })

  // Start on the non-Monaco + node to exercise the hit-test path that previously lost the whole drag.
  test('dragging from the "+" itself selects a range and the button rides the selection', async ({
    orcaPage
  }) => {
    const worktreeId = await waitForActiveWorktree(orcaPage)
    await seedDiffFile(orcaPage, worktreeId, 'src/diff-note-range-button-drag.ts')

    const button = await revealAddButton(orcaPage, 4)
    const to = await gutterPoint(orcaPage, 9)

    await orcaPage.mouse.move(button.x, button.y)
    await orcaPage.mouse.down()
    await orcaPage.mouse.move(button.x, (button.y + to.y) / 2)
    await orcaPage.mouse.move(button.x, to.y)

    await expect(
      orcaPage.locator(BAND),
      'the drag stalled because the pointer stayed over the "+"'
    ).toHaveCount(6)
    await expect
      .poll(
        async () =>
          orcaPage.locator('.orca-diff-comment-add-btn').evaluate((node) => {
            if (!(node instanceof HTMLElement)) {
              throw new Error('the add button is not an HTMLElement')
            }
            return node.style.top
          }),
        { message: 'the "+" did not ride the growing end of the selection' }
      )
      .not.toBe(button.top)

    await orcaPage.mouse.up()
    await expect(orcaPage.locator(COMPOSER_LABEL)).toHaveText('Lines 4-9')
    await submitNote(orcaPage, 'Dragged straight off the plus button.')

    expect(await readNotes(orcaPage, worktreeId)).toEqual([
      { startLine: 4, lineNumber: 9, body: 'Dragged straight off the plus button.' }
    ])
  })

  test('a press with no drag still saves the single-line note it always did', async ({
    orcaPage
  }) => {
    const worktreeId = await waitForActiveWorktree(orcaPage)
    await seedDiffFile(orcaPage, worktreeId, 'src/diff-note-range-click.ts')

    const point = await gutterPoint(orcaPage, 6)
    await orcaPage.mouse.move(point.x, point.y)
    await orcaPage.mouse.down()
    await orcaPage.mouse.up()

    await expect(orcaPage.locator(COMPOSER_LABEL)).toHaveText('Line 6')
    await expect(orcaPage.locator(BAND)).toHaveCount(1)

    await submitNote(orcaPage, 'Single line still works.')

    expect(await readNotes(orcaPage, worktreeId)).toEqual([
      { startLine: undefined, lineNumber: 6, body: 'Single line still works.' }
    ])
    await expect(orcaPage.locator('.orca-diff-comment-card').first()).toContainText('line 6')
  })

  test('Escape abandons a drag without opening a composer', async ({ orcaPage }) => {
    const worktreeId = await waitForActiveWorktree(orcaPage)
    await seedDiffFile(orcaPage, worktreeId, 'src/diff-note-range-escape.ts')

    const from = await gutterPoint(orcaPage, 3)
    const to = await gutterPoint(orcaPage, 8)
    await orcaPage.mouse.move(from.x, from.y)
    await orcaPage.mouse.down()
    await orcaPage.mouse.move(to.x, to.y)
    await expect(orcaPage.locator(BAND)).toHaveCount(6)

    await orcaPage.keyboard.press('Escape')
    await expect(orcaPage.locator(BAND), 'Escape left the band behind').toHaveCount(0)

    await orcaPage.mouse.up()
    await expect(
      orcaPage.locator(COMPOSER),
      'a cancelled drag must not open a composer on release'
    ).toHaveCount(0)
    expect(await readNotes(orcaPage, worktreeId)).toEqual([])
  })

  test('the Add Review Note chord turns an editor selection into a ranged note', async ({
    orcaPage
  }) => {
    const worktreeId = await waitForActiveWorktree(orcaPage)
    await seedDiffFile(orcaPage, worktreeId, 'src/diff-note-range-chord.ts')

    // Click the code column, not the gutter: Monaco still owns that side.
    const line = await gutterPoint(orcaPage, 5)
    await orcaPage.mouse.click(line.x + 220, line.y)
    await orcaPage.keyboard.press('Shift+ArrowDown')
    await orcaPage.keyboard.press('Shift+ArrowDown')

    await pressShortcut(orcaPage, 'KeyA', { shift: true })

    await expect(orcaPage.locator(COMPOSER_LABEL)).toHaveText('Lines 5-7')
    await submitNote(orcaPage, 'Range from the keyboard.')

    expect(await readNotes(orcaPage, worktreeId)).toEqual([
      { startLine: 5, lineNumber: 7, body: 'Range from the keyboard.' }
    ])
  })
})