import * as path from 'path'
import * as fs from 'fs'

import { wrapper, TypeOnEveryFile, TypeToolProp, TypeToolOptions, TypeOnBody } from '@asset-toolkit/core'

export interface TypeProps extends TypeToolOptions {
  chunked?: boolean
  basePath?: string
}

/**
 * A tool to generate font face.
 *
 * @param props - { pathIn, pathOut }
 * @param options - { chunked, basePath }
 * @returns { Promise(returns) }
 */
const fontFaceGenerator: (_props: TypeToolProp, _options?: TypeProps) => Promise<unknown> = wrapper(
  ({ file, wrapperProps, next }: TypeOnEveryFile) => {
    const fontName = file.replace(path.extname(file), '')
    if (!wrapperProps.files[fontName]) wrapperProps.files[fontName] = []
    wrapperProps.files[fontName].push(file)
    next()
  },
  ({ wrapperProps, options, pathOut }: TypeOnBody) => {
    const { basePath, chunked } = options || {}

    const cssOutput = (props: { fontFamily: string; src: string; fontDisplay: string }) =>
      `@font-face {
      font-family: "${props.fontFamily}";
      src: ${props.src};
      font-display: "${props.fontDisplay}";
      }`.trim()

    const outputAll = Object.keys(wrapperProps.files).map(fontName => {
      const files = wrapperProps.files[fontName]

      const fileCssList = files
        .map((file: string) => {
          const type = path.extname(file).replace('.', '')
          return `url("${path.join(basePath || '', file)}") format("${type}")`
        })
        .join(',')

      const output = {
        fontFamily: fontName,
        src: fileCssList,
        fontDisplay: 'swap',
      }

      if (chunked) {
        fs.writeFileSync(path.join(pathOut, `${fontName}.css`), cssOutput(output))
        fs.writeFileSync(path.join(pathOut, `${fontName}.json`), JSON.stringify(output, null, 4))
      }

      return output
    })

    if (!chunked) {
      fs.writeFileSync(path.join(pathOut, `template.css`), outputAll.map((output: any) => cssOutput(output)).join('\n'))
      fs.writeFileSync(path.join(pathOut, `template.json`), JSON.stringify(outputAll, null, 4))
    }
  },
  { exts: ['woff', 'woff2', 'eot', 'ttf'], name: 'Font Face Generator', files: {} },
)

export default fontFaceGenerator