import type { Processor } from '../types'
import type { RangeProcessorOptions } from '../utils/create-range-processor'

import { createRangeProcessor } from '../utils/create-range-processor'
import { addClass } from '../utils'

export interface DiffProcessorOptions extends RangeProcessorOptions {
  commonDiffClass?: string
  removedLinesClasses?: string[]
  addedLinesClasses?: string[]
  removeLineTag?: string
  addLineTag?: string
  hasDiffClass?: string
}

export function createDiffProcessor(options: DiffProcessorOptions = {}): Processor {
  const commonDiffClass = options.commonDiffClass ?? 'diff'
  const removedLinesClasses = options.removedLinesClasses ?? ['remove']
  const addedLinesClasses = options.addedLinesClasses ?? ['add']
  const removeLineTag = options.removeLineTag ?? '--'
  const addLineTag = options.addLineTag ?? '++'
  const hasDiffClass = options.hasDiffClass ?? 'has-diff'
  return {
    name: 'diff',
    handler: createRangeProcessor(
      {
        [removeLineTag]: [commonDiffClass, ...removedLinesClasses],
        [addLineTag]: [commonDiffClass, ...addedLinesClasses]
      },
      options
    ),
    postProcess: ({ code }) => {
      if (!code.includes(commonDiffClass)) {
        return code
      }

      return addClass(code, hasDiffClass, 'pre')
    }
  }
}