import { describe, expect, it, vi } from 'vitest'
import type { FitAddon } from '@xterm/addon-fit'
import type { Terminal } from '@xterm/xterm'
import {
  isTerminalDisposed,
  markTerminalDisposed,
  safeTerminalDispose,
  safeTerminalFit,
  safeTerminalWrite,
} from '../../src/utils/safeTerminalFit'

describe('safeTerminalFit', () => {
  it('returns false without an addon', () => {
    expect(safeTerminalFit(null)).toBe(false)
  })

  it('skips fit when terminal element is detached', () => {
    const fit = vi.fn()
    const term = {
      element: { isConnected: false, parentElement: { clientWidth: 100, clientHeight: 40 } },
    } as unknown as Terminal
    expect(safeTerminalFit({ fit } as unknown as FitAddon, term)).toBe(false)
    expect(fit).not.toHaveBeenCalled()
  })

  it('skips fit when host has zero size', () => {
    const fit = vi.fn()
    const term = {
      element: { isConnected: true, parentElement: { clientWidth: 0, clientHeight: 0 } },
    } as unknown as Terminal
    expect(safeTerminalFit({ fit } as unknown as FitAddon, term)).toBe(false)
    expect(fit).not.toHaveBeenCalled()
  })

  it('swallows renderer dimension races', () => {
    const fit = vi.fn(() => {
      throw new TypeError("undefined is not an object (evaluating 'this._renderer.value.dimensions')")
    })
    const term = {
      element: { isConnected: true, parentElement: { clientWidth: 80, clientHeight: 40 } },
    } as unknown as Terminal
    expect(safeTerminalFit({ fit } as unknown as FitAddon, term)).toBe(false)
    expect(fit).toHaveBeenCalledOnce()
  })

  it('returns true on successful fit', () => {
    const fit = vi.fn()
    const term = {
      element: { isConnected: true, parentElement: { clientWidth: 80, clientHeight: 40 } },
    } as unknown as Terminal
    expect(safeTerminalFit({ fit } as unknown as FitAddon, term)).toBe(true)
  })

  it('blocks write after mark disposed', () => {
    const write = vi.fn()
    const term = { write } as unknown as Terminal
    markTerminalDisposed(term)
    expect(isTerminalDisposed(term)).toBe(true)
    safeTerminalWrite(term, 'x')
    expect(write).not.toHaveBeenCalled()
  })

  it('marks disposed and removes element before dispose', () => {
    const raf: FrameRequestCallback[] = []
    const original = globalThis.requestAnimationFrame
    globalThis.requestAnimationFrame = ((cb: FrameRequestCallback) => {
      raf.push(cb)
      return raf.length
    }) as typeof requestAnimationFrame

    const dispose = vi.fn()
    const remove = vi.fn()
    const term = {
      dispose,
      element: { remove },
    } as unknown as Terminal
    safeTerminalDispose(term)
    expect(isTerminalDisposed(term)).toBe(true)
    expect(remove).toHaveBeenCalledOnce()
    expect(dispose).not.toHaveBeenCalled()
    // Drain double-rAF queue used by safeTerminalDispose.
    while (raf.length) {
      const next = raf.shift()!
      next(0)
    }
    expect(dispose).toHaveBeenCalledOnce()
    globalThis.requestAnimationFrame = original
  })
})