import fs from 'fs'
import crypto from 'crypto'

import matter from 'gray-matter'
import glob from 'fast-glob'
import DataStore from 'nedb-promises'
import dayjs from 'dayjs'

import MakeHtml from '../src/utils/make-html'

// eslint-disable-next-line camelcase
const excerpt_separator = '<!-- excerpt_separator -->'
const db = new DataStore('assets/data.nedb')

;(async () => {
  await db.ensureIndex({ fieldName: 'h', unique: true })

  const files = await glob('**/*.md', {
    cwd: '../../data'
  })
  await Promise.all(files.map(async (f) => {
    let type = ''

    if (f.startsWith('slides/')) {
      type = 'slides'
    }

    const s = fs.readFileSync(`../../data/${f}`, 'utf8')
    const h = crypto.createHash('sha256').update(s).digest('base64')

    const { data, content, excerpt } = matter(s, {
      excerpt_separator
    })

    try {
      if (type === 'slides') {
        const slides = content.split(/\n===\n/g).map((ss) => {
          return ss.split(/\n--\n/g).map((s) => {
            const make = new MakeHtml()
            return make.parse(s)
          }).reduce((prev, c, i) => ({ ...prev, [i.toString()]: c }), {} as any)
        }).reduce((prev, c, i) => ({ ...prev, [i.toString()]: c }), {} as any)

        const computedExcerpt = slides['0']['0']

        await db.insert({
          ...data,
          date: formatDate(data.date),
          filename: f,
          h,
          excerpt: computedExcerpt,
          slides
        })
      } else {
        const make = new MakeHtml()

        let computedExcerpt = ''
        let computedContent = ''

        if (excerpt) {
          computedExcerpt = make.parse(excerpt)
          computedContent = make.parse(content.substr(excerpt.length + excerpt_separator.length))
        } else {
          computedContent = make.parse(content)
          computedExcerpt = computedContent.substr(0, 500).replace(/<[^>]*$/, '')
          computedContent = computedContent.substr(computedExcerpt.length)
        }

        if (data.date) {
          console.log(formatDate(data.date))
        }

        await db.insert({
          ...data,
          date: formatDate(data.date),
          filename: f,
          h,
          excerpt: computedExcerpt,
          remaining: computedContent
        })
      }
    } catch (e) {
      console.error(e, f)
    }
  }))
})().catch(console.error)

const tzOffset = new Date().getTimezoneOffset()

function formatDate (d?: string | Date) {
  if (d) {
    if (typeof d === 'string') {
      return dayjs(d).toDate()
    } else {
      return dayjs(d).add(tzOffset, 'minute').toDate()
    }
  }

  return d
}