index.js

import postcssImport from 'postcss-import'
import postcssNesting from 'postcss-nesting'
import postcssCustomMedia from 'postcss-custom-media'
import autoprefixer from 'autoprefixer'
import { getPackageInfo, deepMergeWith } from 'vituum/utils/common.js'

const { name } = getPackageInfo(import.meta.url)

/**
 * @type {import('@vituum/vite-plugin-postcss/types/index').PluginUserConfig}
 */
const defaultOptions = {
  import: {},
  nesting: {},
  customMedia: {},
  autoprefixer: {},
}

/**
 * @param {import('@vituum/vite-plugin-postcss/types/index').PluginUserConfig} options
 * @returns {import('vite').Plugin}
 */
const plugin = (options = {}) => {
  options = deepMergeWith(defaultOptions, options)

  const postcssPlugins = [
    postcssImport(options.import),
    postcssNesting(options.nesting),
    postcssCustomMedia(options.customMedia),
    autoprefixer(options.autoprefixer),
  ]

  return {
    name,
    enforce: 'pre',
    /** @param {import('@vituum/vite-plugin-postcss/types/viteUserConfig').ViteUserConfig} userConfig */
    config(userConfig) {
      if (!userConfig?.css?.postcss && !userConfig?.css?.postcss?.plugins) {
        userConfig.css = userConfig.css || {}
        userConfig.css.postcss = userConfig.css.postcss || {}
        userConfig.css.postcss.plugins = postcssPlugins
      }
      else if (userConfig.css.postcss.plugins) {
        userConfig.css.postcss.plugins = postcssPlugins.concat(...userConfig.css.postcss.plugins)
      }
    },
  }
}

export default plugin