/*
  This is the builder script that generates the README file.
  Run using `npm run builder`.
*/
// Load modules
const fs = require('fs-extra')
const path = require('path')
const { green, red } = require('kleur')
const util = require('./util')
const markdown = require('markdown-builder')
const { headers, misc, lists } = markdown
const config = require('../config')

// Paths (relative to package.json)
const SNIPPETS_PATH = `./${config.snippetPath}`
const STATIC_PARTS_PATH = `./${config.staticPartsPath}`

// Terminate if parent commit is a Travis build
if (util.isTravisCI() && /^Travis build: \d+/g.test(process.env['TRAVIS_COMMIT_MESSAGE'])) {
  console.log(`${green('NOBUILD')} README build terminated, parent commit is a Travis build!`)
  process.exit(0)
}

// Setup everything
let snippets = {},
  snippetsArray = [],
  startPart = '',
  endPart = '',
  output = ''
const EMOJIS = {}

console.time('Builder')

// Synchronously read all snippets from snippets folder and sort them as necessary (case-insensitive)
snippets = util.readSnippets(SNIPPETS_PATH)
snippetsArray = Object.keys(snippets).reduce((acc, key) => {
  acc.push(snippets[key])
  return acc
}, [])

// Load static parts for the README file
try {
  startPart = fs.readFileSync(path.join(STATIC_PARTS_PATH, 'README-start.md'), 'utf8')
  endPart = fs.readFileSync(path.join(STATIC_PARTS_PATH, 'README-end.md'), 'utf8')
} catch (err) {
  console.log(`${red('ERROR!')} During static part loading: ${err}`)
  process.exit(1)
}

// Create the output for the README file
try {
  const tags = util.prepTaggedData(
    Object.keys(snippets).reduce((acc, key) => {
      acc[key] = snippets[key].attributes.tags
      return acc
    }, {})
  )

  output += `${startPart}\n`

  // Loop over tags and snippets to create the table of contents
  for (const tag of tags) {
    const capitalizedTag = util.capitalize(tag, true)
    const taggedSnippets = snippetsArray.filter(snippet => snippet.attributes.tags[0] === tag)
    output += headers.h3((EMOJIS[tag] || '') + ' ' + capitalizedTag).trim()

    output +=
      misc.collapsible(
        'View contents',
        lists.ul(taggedSnippets, snippet =>
          misc.link(
            `\`${snippet.title}\``,
            `${misc.anchor(snippet.title)}${
              snippet.attributes.tags.includes('advanced') ? '-' : ''
            }`
          )
        )
      ) + '\n'
  }

  for (const tag of tags) {
    const capitalizedTag = util.capitalize(tag, true)
    const taggedSnippets = snippetsArray.filter(snippet => snippet.attributes.tags[0] === tag)

    output += misc.hr() + headers.h2((EMOJIS[tag] || '') + ' ' + capitalizedTag) + '\n'

    for (let snippet of taggedSnippets) {
      if (snippet.attributes.tags.includes('advanced'))
        output += headers.h3(snippet.title + ' ' + misc.image('advanced', '/advanced.svg')) + '\n'
      else output += headers.h3(snippet.title) + '\n'

      output += snippet.attributes.text

      output += `\`\`\`${config.secondLanguage}\n${snippet.attributes.codeBlocks.html}\n\`\`\`\n\n`
      output += `\`\`\`${config.language}\n${snippet.attributes.codeBlocks.css}\n\`\`\`\n\n`
      if (snippet.attributes.codeBlocks.js)
        output += `\`\`\`${config.optionalLanguage}\n${snippet.attributes.codeBlocks.js}\n\`\`\`\n\n`

      output += headers.h4('Explanation')
      output += snippet.attributes.explanation

      output += headers.h4('Browser support') + '\n'
      output += snippet.attributes.browserSupport.supportPercentage.toFixed(1) + '%'
      output += snippet.attributes.browserSupport.text

      output += '\n<br>' + misc.link('⬆ Back to top', misc.anchor('Contents')) + '\n'
    }
  }

  // Add the ending static part
  output += `\n${endPart}\n`
  // Write to the README file
  fs.writeFileSync('README.md', output)
} catch (err) {
  console.log(`${red('ERROR!')} During README generation: ${err}`)
  process.exit(1)
}

console.log(`${green('SUCCESS!')} README file generated!`)
console.timeEnd('Builder')