import { PostResourceTransformer } from "../types"

import path from 'path'
import { promises as fs } from 'fs'
import glslx from 'glslx'

const transformer : PostResourceTransformer = {
  extension: "glsl",
  transform: async (value) => {
    const argPath = path.join(process.cwd(), 'scripts', value)
    const argContents = await fs.readFile(argPath)
    const argFileName = path.basename(value)

    const {output: glslResult, log} = glslx.compile({name: argFileName, contents: argContents.toString('utf8')})
    if (!glslResult) {
      console.error(log)
      throw new Error("Could not parse GLSL file")
    }

    const argDest = path.join(process.cwd(), '.next/static/scripts', value)
    const argDir = path.dirname(argDest)
    await fs.mkdir(argDir, { recursive: true })
    await fs.writeFile(argDest, argContents)

    return {
      type: "resource",
      name: argFileName,
      path: path.join('/_next/static/scripts', value)
    }
  }
}

export default transformer