import { readFileSync, writeFileSync, readdirSync } from 'node:fs'
import { fileURLToPath } from 'node:url'
import { dirname, join, relative } from 'node:path'

const __filename = fileURLToPath(import.meta.url)
const __dirname = dirname(__filename)

const buildDir = join(__dirname, '..', 'build')
const files = (await readdirSync(buildDir, { recursive: true }))
  .filter(file => file.endsWith('.js'))
  .map(file => join(buildDir, file))

for (const file of files) {
  reflectType(file, { debug: true })
}

function reflectType(srcFile, options = { debug: false }) {
  log(`Reflecting file "${relative(__dirname, srcFile)}"`)

  const defFile = srcFile.replace(/.js$/, '.d.ts')
  const src = String(readFileSync(srcFile))
  const defs = String(readFileSync(defFile))

  if (src.includes('.reflectedType5')) {
    log('  Source file already contains reflected types and will be ignored')
    return
  }

  const matches = Array.from(src.matchAll(/[^\n](export +)?const +([\w$]+) += +implementations\b/g))

  if (matches.length === 0) {
    log(`  No implementations found`)
    return
  }

  for (const match of matches) {
    const name = match[2]
    log(`  Found an implementations definition: "${name}"`)

    const def = new RegExp(`export declare const ${name}: {(?:(?!\n}).)+\n}`, 's').exec(defs)

    if (def) {
      log(`  Injected type definitions for "${name}"`)

      const srcReflected = `${src}\n${name}.reflectedType5 = \`${def}\`\n`

      writeFileSync(srcFile, srcReflected)
    } else {
      log(`  No type definitions found for "${name}"`)
    }
  }

  function log(...args) {
    if (options.debug) {
      console.log(...args)
    }
  }
}