import html from '@rollup/plugin-html'
import { nodeResolve } from '@rollup/plugin-node-resolve'
import replace from '@rollup/plugin-replace'
import fs from 'fs'
import { createFilter } from '@rollup/pluginutils'
import { compileScript, compileStyleAsync, compileTemplate, parse } from '@vue/compiler-sfc'
import postcss from 'postcss'
import url from 'postcss-url'
import path from 'path'
import cssnano from 'cssnano'
import terser from '@rollup/plugin-terser'

const DEFAULT_VARIABLE = '__script__'

function isProduction () {
  return process.env.NODE_ENV === 'production'
}

function transformScript (descriptor, id) {
  if (descriptor.script === null && descriptor.scriptSetup === null) {
    return {
      bindings: {},
      code: 'export default {}',
      map: null,
      descriptor
    }
  }
  const script = compileScript(descriptor, {
    id,
    isProd: isProduction(),
    sourceMap: true,
    inlineTemplate: isProduction()
  })

  return {
    bindings: script.bindings,
    code: script.content,
    map: script.map,
    descriptor
  }
}

function transformOptions (code) {
  const newCode = code
    .replaceAll('__VUE_OPTIONS_API__', 'true')
    .replaceAll('__VUE_PROD_DEVTOOLS__', 'false')

  return {
    code: newCode,
    map: null
  }
}

function vuePostcss (options = {}) {
  const filter = createFilter(options.include, options.exclude)
  const styles = []
  const components = new Map()
  const processor = postcss(options.postcssPlugins || [])
  let cssFileName = options.cssFileName

  return {
    name: 'vue-postcss',
    renderStart (outputOptions, inputOptions) {
      if (cssFileName) {
        return
      }
      if (inputOptions.input.length === 0) {
        this.error('cssFileName should be specified or there should be at least one input file.')
      }
      cssFileName = path.basename(inputOptions.input[0], '.js') + '.css'
    },
    async load (id) {
      const [path, rawQueryString] = id.split('?')

      if (!path.endsWith('.vue') || rawQueryString === undefined) {
        return null
      }
      const queryString = new URLSearchParams(rawQueryString)
      const component = components.get(path)
      let snippet = {}

      switch (queryString.get('type')) {
        case 'template':
          snippet = compileTemplate({
            source: component.descriptor.template.content,
            id,
            filename: id,
            isProd: isProduction(),
            inMap: component.descriptor.template.map,
            compilerOptions: {
              inline: false,
              bindingMetadata: component.bindings
            }
          })
          return snippet.preamble + snippet.code
        case 'script':
          return component.code
        default:
          this.error(`Unknown vue type "${queryString.get('type')}"`)
      }
    },
    async transform (code, id) {
      if (!filter(id)) {
        return
      }
      if (id.endsWith('/node_modules/@vue/runtime-core/dist/runtime-core.esm-bundler.js')) {
        return transformOptions(code)
      }
      if (!id.endsWith('.vue')) {
        return
      }
      const parseResult = parse(code, {
        sourceMap: true,
        filename: id
      })
      // Throws an exception without location information, which is handled by
      // rollup.
      components.set(id, transformScript(parseResult.descriptor, id))

      // Each component can have multiple style tags processed with PostCSS.
      for (const style of parseResult.descriptor.styles) {
        const compiledStyle = await compileStyleAsync({
          source: style.content,
          filename: id,
          id,
          inMap: style.map,
          isProd: isProduction()
        })
        styles.push(compiledStyle.rawResult)
      }

      const source = `import { render } from '${id}?vue&type=template'\n` +
        `import ${DEFAULT_VARIABLE} from '${id}?vue&type=script'\n` +
        `${DEFAULT_VARIABLE}.render = render\n` +
        `${DEFAULT_VARIABLE}.__file = '${id}'\n` +
        `export default ${DEFAULT_VARIABLE}\n`

      return {
        code: source,
        map: components.get(id).map
      }
    },
    async generateBundle (options, bundle) {
      const root = postcss.document()

      for (const compiledStyle of styles) {
        const processedStyle = await processor.process(compiledStyle, {
          ...compiledStyle.opts,
          to: path.resolve(`${options.dir}/${cssFileName}`)
        })
        processedStyle.messages.forEach(message => {
          switch (message.type) {
            case 'warning':
              this.warn({
                message: message.text,
                loc: { column: message.column, line: message.line },
                id: processedStyle.opts.from
              })
              break
          }
        })

        root.append(processedStyle.root)
      }
      const mapName = cssFileName + '.map'
      const result = root.toResult({
        to: cssFileName,
        map: {
          annotation: mapName
        }
      })

      this.emitFile({
        type: 'asset',
        id: cssFileName,
        fileName: cssFileName,
        source: result.css
      })
      if (options.sourcemap) {
        this.emitFile({
          type: 'asset',
          id: mapName,
          fileName: mapName,
          source: result.map.toString()
        })
      }
    }
  }
}

export default {
  input: 'assets/index.js',
  output: {
    dir: 'dist',
    format: 'iife',
    sourcemap: true
  },
  plugins: [
    replace({
      values: {
        'process.env.NODE_ENV': JSON.stringify(process.env.NODE_ENV || 'development')
      },
      preventAssignment: true
    }),
    nodeResolve(),
    vuePostcss({
      postcssPlugins: [
        url({
          url: 'copy',
          basePath: path.resolve('assets'),
          assetsPath: '.',
          useHash: false
        }),
        cssnano()
      ]
    }),
    html({
      title: 'Hora Bona',
      template ({ files, publicPath, title }) {
        const contents = fs.readFileSync('assets/index.html')
          .toString()
          .replace(/<title><\/title>/, `<title>${title}</title>`)
        const scripts = files.js.map(function (file) {
          return `<script defer src="${publicPath}${file.fileName}"></script>`
        })
        const styles = files.css.map(function (file) {
          return `<link rel="stylesheet" href="${publicPath}${file.fileName}">`
        })
        const headEnd = contents.search('</head>')

        return contents.slice(0, headEnd) +
          scripts.join('\n') +
          styles.join('\n') +
          contents.slice(headEnd)
      }
    }),
    isProduction() && terser() // See: https://github.com/rollup/plugins/issues/1371
  ]
}