import fs from 'fs'
import path from 'path'
import { defineConfig } from 'vite'
import serveStatic from 'serve-static'

export default defineConfig(async ({ mode }) => {
  // const {
  //   default: { vitePrefabPlugin },
  // } = await import('@thing.js/cli-p-prefab')
  const { vitePrefabPlugin } = await import('@thing.js/cli-p-prefab')
  return {
    plugins: [
      startLocalServe(),
      transformHtml(),
      mode === 'development' &&
        vitePrefabPlugin({
          input: 'src',
          outputDir: 'dist',
          watch: true,
          reloadAfterBuild: true,
          reloadFilter: ({ file, type }) => {
            return path.basename(file) === 'prefab.json' && type !== 'unlink'
          },
        }),
    ],
  }
})

/**
 * Start packaging prefab
 */
function startLocalServe() {
  return {
    name: 'local-serve',
    async configureServer(server) {
      const app = server.middlewares
      app.use(serveStatic('dist'))
      app.use('/local-api/export-data', (req, res) => {
        const data = []
        req.on('data', (chunk) => {
          data.push(chunk)
        })
        req.on('end', () => {
          try {
            let newObj = JSON.parse(Buffer.concat(data).toString())
            let result = {}
            const tsfPath = path.resolve(__dirname, 'src/prefab.json')
            if (fs.existsSync(tsfPath)) {
              try {
                const oldObj = JSON.parse(fs.readFileSync(tsfPath, 'utf8'))
                const headers = [
                  'name',
                  'id',
                  'version',
                  'author',
                  'description',
                ]

                // Place the old header in front
                for (const key in oldObj) {
                  if (
                    headers.includes(key) &&
                    typeof oldObj[key] !== 'undefined'
                  ) {
                    result[key] = oldObj[key]
                  }
                }
              } catch (e) {
                console.error(e)
              }
            }

            for (const key in newObj) {
              result[key] = newObj[key]
            }
            fs.writeFileSync(tsfPath, JSON.stringify(result, null, 2))
            res.end()
          } catch (e) {
            console.log(e)
          }
        })
      })
    },
  }
}

/**
 * Inject export script to index.html
 */
function transformHtml() {
  return {
    name: 'transform-html',
    transformIndexHtml() {
      return [
        {
          tag: 'script',
          attrs: {
            type: 'module',
          },
          children: `
          import exportData from "./dist/index.js";
          fetch('/local-api/export-data', {method: 'POST', body: JSON.stringify(exportData(), null, 2)})
          `,
          injectTo: 'body',
        },
      ]
    },
  }
}