import * as babel from "@babel/core"
import type { PluginOption, TransformResult } from "vite"

const sourceRegex = /\.(j|t)sx?$/

export default function macrosPlugin(): PluginOption {
  return {
    name: "babel-macros",
    enforce: "pre",
    transform(source: string, filename: string) {
      if (filename.includes("node_modules")) {
        return undefined
      }
      if (!sourceRegex.test(filename)) {
        return
      }
      const hasBabelMacro = source.includes('.macro"')
      const hasEmotion = source.includes("@emotion")
      if (!hasBabelMacro && !hasEmotion) {
        return undefined
      }
      const result = babel.transformSync(source, {
        filename,
        parserOpts: {
          plugins: ["jsx", "typescript", "decorators-legacy"],
        },
        plugins: [
          hasBabelMacro && require.resolve("babel-plugin-macros"),
          hasEmotion && require.resolve("@emotion/babel-plugin"),
        ].filter(Boolean),
        generatorOpts: {
          decoratorsBeforeExport: true,
        },
        babelrc: false,
        configFile: false,
        sourceMaps: true,
      })
      return result as TransformResult | null
    },
  }
}