import { mount } from '@vue/test-utils'
import { describe, expect, it, vi } from 'vitest'
import { defineComponent, h } from 'vue'
import { useDragOrClick } from '@/composables/timetable/useDragOrClick'

interface ComponentInstance {
  begin: (e: Event) => void
}

function makeHost(opts: Parameters<typeof useDragOrClick>[0]) {
  return defineComponent({
    setup(_, { expose }) {
      const ctl = useDragOrClick(opts)

      expose({ begin: ctl.begin })

      return () => h('div')
    },
  })
}

function makePointerEvent(type: string, x: number, y: number, pointerId = 1): PointerEvent {
  const e = new Event(type, { bubbles: true, cancelable: true }) as PointerEvent

  Object.defineProperty(e, 'pointerId', { value: pointerId })
  Object.defineProperty(e, 'clientX', { value: x })
  Object.defineProperty(e, 'clientY', { value: y })

  return e
}

describe('useDragOrClick', () => {
  it('fires onClick when movement < threshold', async () => {
    const onClick = vi.fn()
    const onDragStart = vi.fn()
    const wrapper = mount(makeHost({ thresholdPx: 4, onClick, onDragStart }))
    const inst = wrapper.vm as unknown as ComponentInstance

    inst.begin(makePointerEvent('pointerdown', 10, 10))
    window.dispatchEvent(makePointerEvent('pointermove', 11, 11))
    window.dispatchEvent(makePointerEvent('pointerup', 11, 11))

    expect(onClick).toHaveBeenCalledTimes(1)
    expect(onDragStart).not.toHaveBeenCalled()
  })

  it('enters drag mode and emits onDragStart + onDragEnd when movement crosses threshold', async () => {
    const onClick = vi.fn()
    const onDragStart = vi.fn()
    const onDragEnd = vi.fn()
    const wrapper = mount(makeHost({ thresholdPx: 4, onClick, onDragStart, onDragEnd }))
    const inst = wrapper.vm as unknown as ComponentInstance

    inst.begin(makePointerEvent('pointerdown', 10, 10))
    window.dispatchEvent(makePointerEvent('pointermove', 50, 10))
    window.dispatchEvent(makePointerEvent('pointerup', 50, 10))

    expect(onDragStart).toHaveBeenCalledTimes(1)
    expect(onDragEnd).toHaveBeenCalledTimes(1)
    expect(onClick).not.toHaveBeenCalled()
  })

  it('Esc cancels an in-flight drag', async () => {
    const onDragEnd = vi.fn()
    const wrapper = mount(makeHost({ thresholdPx: 4, onDragEnd }))
    const inst = wrapper.vm as unknown as ComponentInstance

    inst.begin(makePointerEvent('pointerdown', 10, 10))
    window.dispatchEvent(makePointerEvent('pointermove', 50, 10))

    const esc = new KeyboardEvent('keydown', { key: 'Escape' })

    window.dispatchEvent(esc)

    expect(onDragEnd).toHaveBeenCalledWith(expect.anything(), true)
  })
})