const nest = require('depnest')
const { h, computed, map, send, when, onceTrue } = require('mutant')
const TagHelper = require('scuttle-tag')
const msgs = require('ssb-msgs')

exports.gives = nest('message.html.metas')
exports.needs = nest({
  'message.obs.likeCount': 'first',
  'sheet.profiles': 'first',
  'about.obs.name': 'first',
  'intl.sync.i18n': 'first',
  'intl.sync.i18n_n': 'first',
  'sbot.obs.connection': 'first',
  'sheet.tags.render': 'first',
  'about.html.image': 'first'
})

exports.create = function (api) {
  const i18n = api.intl.sync.i18n
  const plural = api.intl.sync.i18n_n

  return nest('message.html.metas', function likes (msg) {
    const ScuttleTag = TagHelper(api.sbot.obs.connection)

    const result = []
    if (msg.value.private) {
      result.push(h('span.private', map(msg.value.content.recps, id => {
        const feed = msgs.link(id, 'feed')
        if (!feed) return
        id = feed.link
        return h('a', {
          href: id,
          title: api.about.obs.name(id)
        }, [
          api.about.html.image(id)
        ])
      })))
    }

    if (msg.value.content && msg.value.content.channel && msg.value.content.type !== 'channel') {
      result.push(h('a.channel', { href: `#${msg.value.content.channel}` }, [`#${msg.value.content.channel}`]))
    }

    if (msg.key) {
      const likeCount = api.message.obs.likeCount(msg.key)
      result.push(
        h('div.counts', [
          when(likeCount,
            h('a.likes', {
              href: '#', 'ev-click': send(displayLikes, msg)
            }, computed(['%s likes', likeCount], plural))
          ),
          computed(ScuttleTag.obs.messageTags(msg.key), (tags) => tagCount(msg.key, tags))
        ])
      )
    }

    return result
  })

  function displayLikes (msg) {
    onceTrue(api.sbot.obs.connection, (sbot) => {
      sbot.patchwork.likes.get({ dest: msg.key }, (err, likes) => {
        if (err) return console.log(err)
        api.sheet.profiles(likes, i18n('Liked by'))
      })
    })
  }

  function tagCount (msgId, tags) {
    if (tags.length) {
      return [' ', h('a.tags', {
        title: tagList('Tags', tags),
        href: '#',
        'ev-click': send(displayTags, { msgId, tags })
      }, [`${tags.length} ${tags.length === 1 ? 'tag' : 'tags'}`])]
    }
  }

  function tagList (prefix, ids) {
    const items = map(ids, api.about.obs.name)
    return computed([prefix, items], (prefix, names) => {
      return (prefix ? (prefix + '\n') : '') + names.map((n) => `- ${n}`).join('\n')
    })
  }

  function displayTags ({ msgId, tags }) {
    api.sheet.tags.render(msgId, tags)
  }
}