import assert from 'node:assert/strict'
import test from 'node:test'
import { ref } from 'vue'
import { useAdminMarkdownPreviewFocus } from '../composables/useAdminMarkdownPreviewFocus.js'

/**
 * 테스트용 source line DOM 대역을 만든다.
 * @param {Object} options - 줄 옵션
 * @returns {Object} 줄 DOM 대역
 */
const createSourceLineStub = (options) => {
  return {
    line: options.line,
    rect: options.rect,
    closest: (selector) => selector === '[data-source-line]' ? options.closestResult ?? null : null,
    getAttribute: (name) => name === 'data-source-line' ? String(options.line) : null,
    getBoundingClientRect: () => options.rect
  }
}

/**
 * 테스트용 미리보기 표면 상태를 만든다.
 * @param {Object} options - 테스트 옵션
 * @returns {Object} 테스트 상태
 */
const createPreviewFocusState = (options = {}) => {
  const calls = {
    focusEditableAtLine: [],
    selectAllLiveDocument: 0
  }
  const sourceLines = options.sourceLines ?? []
  const surface = {
    scrollTop: options.scrollTop ?? 80,
    contains: (element) => options.containedElements?.includes(element) ?? false,
    querySelectorAll: (selector) => selector === '[data-source-line]' ? sourceLines : [],
    getBoundingClientRect: () => options.surfaceRect ?? {
      top: 10,
      bottom: 600,
      height: 590
    }
  }
  const previewSurfaceRef = ref({
    getPreviewElement: () => surface,
    getSourceLineElement: (sourceLine) => sourceLines.find((line) => line.line === sourceLine) ?? null,
    focusEditableAtLine: (...args) => {
      calls.focusEditableAtLine.push(args)
    },
    selectAllLiveDocument: () => {
      calls.selectAllLiveDocument += 1
    }
  })
  const focusState = useAdminMarkdownPreviewFocus({
    previewSurfaceRef,
    isClient: true,
    getActiveElement: () => options.activeElement ?? null
  })

  return {
    calls,
    focusState,
    previewSurfaceRef,
    sourceLines,
    surface
  }
}

test('미리보기 표면 함수 호출을 표면 컴포넌트로 위임한다', () => {
  const line = createSourceLineStub({
    line: 3,
    rect: { top: 40, bottom: 70, height: 30 }
  })
  const state = createPreviewFocusState({
    sourceLines: [line]
  })

  assert.equal(state.focusState.getPreviewSurfaceElement(), state.surface)
  assert.equal(state.focusState.getPreviewSourceLineElement(3), line)

  state.focusState.focusPreviewEditableAtLine(3, 0, 'start')
  state.focusState.selectAllPreviewDocument()

  assert.deepEqual(state.calls.focusEditableAtLine, [[3, 0, 'start']])
  assert.equal(state.calls.selectAllLiveDocument, 1)
})

test('미리보기 상단 스크롤을 0으로 되돌린다', () => {
  const state = createPreviewFocusState()

  state.focusState.scrollPreviewToTop()

  assert.equal(state.surface.scrollTop, 0)
})

test('현재 포커스가 미리보기 줄 안에 있으면 해당 source line을 반환한다', () => {
  const focusedLine = createSourceLineStub({
    line: 7,
    rect: { top: 240, bottom: 270, height: 30 }
  })
  const activeElement = {
    closest: (selector) => selector === '[data-source-line]' ? focusedLine : null
  }
  const state = createPreviewFocusState({
    activeElement,
    containedElements: [activeElement],
    sourceLines: [focusedLine]
  })

  assert.equal(state.focusState.getCurrentPreviewSourceLine(), 7)
})

test('포커스 줄이 없으면 화면 상단 기준으로 가까운 source line을 반환한다', () => {
  const firstLine = createSourceLineStub({
    line: 1,
    rect: { top: 4, bottom: 20, height: 16 }
  })
  const secondLine = createSourceLineStub({
    line: 2,
    rect: { top: 40, bottom: 70, height: 30 }
  })
  const thirdLine = createSourceLineStub({
    line: 3,
    rect: { top: 120, bottom: 150, height: 30 }
  })
  const state = createPreviewFocusState({
    sourceLines: [thirdLine, firstLine, secondLine],
    surfaceRect: {
      top: 10,
      bottom: 500,
      height: 490
    }
  })

  assert.equal(state.focusState.getCurrentPreviewSourceLine(), 2)
})

test('클라이언트가 아니거나 표면이 없으면 현재 줄을 반환하지 않는다', () => {
  const previewSurfaceRef = ref(null)
  const focusState = useAdminMarkdownPreviewFocus({
    previewSurfaceRef,
    isClient: false
  })

  assert.equal(focusState.getCurrentPreviewSourceLine(), null)
})