const nest = require('depnest')
const { h, when, computed, Value } = require('mutant')
var htmlEscape = require('html-escape')
const addSuggest = require('suggest-box')

exports.needs = nest({
  'book.obs.book': 'first',
  'about.html.image': 'first',
  'about.obs.name': 'first',
  'keys.sync.id': 'first',
  'emoji.async.suggest': 'first',
  'emoji.sync.url': 'first',
  'message.html': {
    'markdown': 'first'
  },
  'book.html': {
    'title': 'first',
    'authors': 'first',
    'description': 'first',
    'images': 'first'
  }
})

exports.gives = nest('book.html.layout')

exports.create = (api) => {
  return nest('book.html.layout', bookLayout)

  function renderEmoji (emoji, url) {
    if (!url) return ':' + emoji + ':'
    return `
      <img
        src="${htmlEscape(url)}"
        alt=":${htmlEscape(emoji)}:"
        title=":${htmlEscape(emoji)}:"
        class="emoji"
      >
    `
  }

  function simpleMarkdown(text) {
    if (text.startsWith(':'))
      return renderEmoji(text, api.emoji.sync.url(text.match(/:([^:]*)/)[1]))
    else
      return text
  }
  
  function ratingEdit(isEditing, value) {
    return when(isEditing,
                h('input', {'ev-input': e => value.set(e.target.value), value: value,
                            placeholder: 'your rating' }),
                h('span.text', { innerHTML: computed(value, simpleMarkdown) }))
  }

  function ratingTypeEdit(isEditing, value) {
    let getEmojiSuggestions = api.emoji.async.suggest()

    let ratingTypeInput = h('input', {'ev-input': e => value.set(e.target.value),
                                      value: value, placeholder: 'rating type' })

    let suggestWrapper = h('span.ratingType', ratingTypeInput)

    addSuggest(ratingTypeInput, (inputText, cb) => {
      if (inputText[0] === ':') {
        cb(null, getEmojiSuggestions(inputText.slice(1)))
      }
    }, {cls: 'PatchSuggest'})

    return when(isEditing, suggestWrapper,
                h('span.text', { innerHTML: computed(value, simpleMarkdown) }))
  }

  function simpleEdit(isEditing, name, value) {
    return h('div', { classList: when(computed([value, isEditing], (v, e) => { return v || e }),
                                      '-expanded', '-contracted') },
             [h('span', name + ':'),
              when(isEditing,
                   h('input', {'ev-input': e => value.set(e.target.value), value: value }),
                   h('span', value))])

  }

  function textEdit(isEditing, name, value) {
    const markdown = api.message.html.markdown
    const input = h('textarea', {'ev-input': e => value.set(e.target.value), value: value })

    return h('div', { classList: when(computed([value, isEditing], (v, e) => { return v || e }),
                                      '-expanded', '-contracted') },
             [h('div', name + ':'),
              when(isEditing, input, computed(value, markdown))])
  }

  function bookLayout (msg, opts) {
    if (!(opts.layout === undefined || opts.layout === 'detail')) return

    const { obs, isEditing, isCard } = opts

    const { title, authors, description, images } = api.book.html

    let isEditingSubjective = Value(false)
    let reviews = []

    return [h('Message -book-detail', [
      title({ title: obs.title, msg, isEditing, onUpdate: obs.title.set }),
      authors({authors: obs.authors, isEditing, onUpdate: obs.authors.set}),
      h('section.content', [
        images({images: obs.images, isEditing, onUpdate: obs.images.add }),
        h('section.description',
          description({description: obs.description, isEditing, onUpdate: obs.description.set})),
      ]),
      h('section.actions', [
        h('button.edit', { 'ev-click': () => isEditing.set(!isEditing()) },
          when(isEditing, 'Cancel', 'Edit book')),
        when(isEditing, h('button', {'ev-click': () => saveBook(obs)}, 'Update book'))
      ]),
      h('section.subjective', [
        computed(obs.subjective, subjectives => {
          let i = 0;
          Object.keys(subjectives).forEach(user => {
            if (i++ < reviews.length) return
            let subjective = obs.subjective.get(user)
            let isMe = Value(api.keys.sync.id() == user)
            let isOwnEditingSubj = computed([isEditingSubjective, isMe],
                                            (e, me) => { return e && me })
            reviews.push([
              h('section', [api.about.html.image(user),
                            when(computed([subjective.rating, isEditingSubjective],
                                          (v, e) => { return v || e }),
                                 h('span.text', [api.about.obs.name(user), ' rated '])),
                            ratingEdit(isOwnEditingSubj, subjective.rating),
                            ratingTypeEdit(isOwnEditingSubj, subjective.ratingType)]),
              simpleEdit(isOwnEditingSubj, 'Shelve', subjective.shelve),
              simpleEdit(isOwnEditingSubj, 'Genre', subjective.genre),
              textEdit(isOwnEditingSubj, 'Review', subjective.review)
            ])
          })

          return reviews
        })
      ]),
      h('section.actions', [
        h('button.subjective', { 'ev-click': () => isEditingSubjective.set(!isEditingSubjective()) },
          when(isEditingSubjective, 'Cancel', 'Edit rating')),
        when(isEditingSubjective, h('button', { 'ev-click': () => saveSubjective(obs) }, 'Update rating'))
      ]),
    ])]

    function saveBook(obs) {
      obs.amend()

      isEditing.set(false)
    }

    function saveSubjective(obs) {
      obs.updateSubjective()

      isEditingSubjective.set(false)
    }
  }
}