class Markup {
  forceReply (value = true) {
    this.force_reply = value
    return this
  }

  removeKeyboard (value = true) {
    this.remove_keyboard = value
    return this
  }

  inputFieldPlaceholder (placeholder) {
    this.input_field_placeholder = placeholder
    return this
  }

  selective (value = true) {
    this.selective = value
    return this
  }

  extra (options) {
    return {
      reply_markup: { ...this },
      ...options
    }
  }

  keyboard (buttons, options) {
    const keyboard = buildKeyboard(buttons, { columns: 1, ...options })
    if (keyboard && keyboard.length > 0) {
      this.keyboard = keyboard
    }
    return this
  }

  resize (value = true) {
    this.resize_keyboard = value
    return this
  }

  oneTime (value = true) {
    this.one_time_keyboard = value
    return this
  }

  inlineKeyboard (buttons, options) {
    const keyboard = buildKeyboard(buttons, { columns: buttons.length, ...options })
    if (keyboard && keyboard.length > 0) {
      this.inline_keyboard = keyboard
    }
    return this
  }

  button (text, hide) {
    return Markup.button(text, hide)
  }

  contactRequestButton (text, hide) {
    return Markup.contactRequestButton(text, hide)
  }

  locationRequestButton (text, hide) {
    return Markup.locationRequestButton(text, hide)
  }

  pollRequestButton (text, type, hide) {
    return Markup.pollRequestButton(text, type, hide)
  }

  urlButton (text, url, hide) {
    return Markup.urlButton(text, url, hide)
  }

  callbackButton (text, data, hide) {
    return Markup.callbackButton(text, data, hide)
  }

  switchToChatButton (text, value, hide) {
    return Markup.switchToChatButton(text, value, hide)
  }

  switchToCurrentChatButton (text, value, hide) {
    return Markup.switchToCurrentChatButton(text, value, hide)
  }

  gameButton (text, hide) {
    return Markup.gameButton(text, hide)
  }

  payButton (text, hide) {
    return Markup.payButton(text, hide)
  }

  loginButton (text, url, opts, hide) {
    return Markup.loginButton(text, url, opts, hide)
  }

  static removeKeyboard (value) {
    return new Markup().removeKeyboard(value)
  }

  static forceReply (value) {
    return new Markup().forceReply(value)
  }

  static keyboard (buttons, options) {
    return new Markup().keyboard(buttons, options)
  }

  static inlineKeyboard (buttons, options) {
    return new Markup().inlineKeyboard(buttons, options)
  }

  static resize (value = true) {
    return new Markup().resize(value)
  }

  static inputFieldPlaceholder (placeholder) {
    return new Markup().inputFieldPlaceholder(placeholder)
  }

  static selective (value = true) {
    return new Markup().selective(value)
  }

  static oneTime (value = true) {
    return new Markup().oneTime(value)
  }

  static button (text, hide = false) {
    return { text: text, hide: hide }
  }

  static contactRequestButton (text, hide = false) {
    return { text: text, request_contact: true, hide: hide }
  }

  static locationRequestButton (text, hide = false) {
    return { text: text, request_location: true, hide: hide }
  }

  static pollRequestButton (text, type, hide = false) {
    return { text: text, request_poll: { type }, hide: hide }
  }

  static urlButton (text, url, hide = false) {
    return { text: text, url: url, hide: hide }
  }

  static callbackButton (text, data, hide = false) {
    return { text: text, callback_data: data, hide: hide }
  }

  static switchToChatButton (text, value, hide = false) {
    return { text: text, switch_inline_query: value, hide: hide }
  }

  static switchToCurrentChatButton (text, value, hide = false) {
    return { text: text, switch_inline_query_current_chat: value, hide: hide }
  }

  static gameButton (text, hide = false) {
    return { text: text, callback_game: {}, hide: hide }
  }

  static payButton (text, hide = false) {
    return { text: text, pay: true, hide: hide }
  }

  static loginButton (text, url, opts = {}, hide = false) {
    return {
      text: text,
      login_url: { ...opts, url: url },
      hide: hide
    }
  }

  static formatHTML (text = '', entities = []) {
    const available = [...entities]
    const opened = []
    const result = []
    for (let offset = 0; offset < text.length; offset++) {
      while (true) {
        const index = available.findIndex((entity) => entity.offset === offset)
        if (index === -1) {
          break
        }
        const entity = available[index]
        switch (entity.type) {
          case 'bold':
            result.push('<b>')
            break
          case 'italic':
            result.push('<i>')
            break
          case 'code':
            result.push('<code>')
            break
          case 'pre':
            if (entity.language) {
              result.push(`<pre><code class="language-${entity.language}">`)
            } else {
              result.push('<pre>')
            }
            break
          case 'strikethrough':
            result.push('<s>')
            break
          case 'underline':
            result.push('<u>')
            break
          case 'text_mention':
            result.push(`<a href="tg://user?id=${entity.user.id}">`)
            break
          case 'text_link':
            result.push(`<a href="${entity.url}">`)
            break
        }
        opened.unshift(entity)
        available.splice(index, 1)
      }

      result.push(escapeHTML(text[offset]))

      while (true) {
        const index = opened.findIndex((entity) => entity.offset + entity.length - 1 === offset)
        if (index === -1) {
          break
        }
        const entity = opened[index]
        switch (entity.type) {
          case 'bold':
            result.push('</b>')
            break
          case 'italic':
            result.push('</i>')
            break
          case 'code':
            result.push('</code>')
            break
          case 'pre':
            if (entity.language) {
              result.push('</code></pre>')
            } else {
              result.push('</pre>')
            }
            break
          case 'strikethrough':
            result.push('</s>')
            break
          case 'underline':
            result.push('</u>')
            break
          case 'text_mention':
          case 'text_link':
            result.push('</a>')
            break
        }
        opened.splice(index, 1)
      }
    }
    return result.join('')
  }
}

const escapedChars = {
  '"': '&quot;',
  '&': '&amp;',
  '<': '&lt;',
  '>': '&gt;'
}

function escapeHTML (string) {
  const chars = [...string]
  return chars.map(char => escapedChars[char] || char).join('')
}

function buildKeyboard (buttons, options) {
  const result = []
  if (!Array.isArray(buttons)) {
    return result
  }
  if (buttons.find(Array.isArray)) {
    return buttons.map(row => row.filter((button) => !button.hide))
  }
  const wrapFn = options.wrap
    ? options.wrap
    : (btn, index, currentRow) => currentRow.length >= options.columns
  let currentRow = []
  let index = 0
  for (const btn of buttons.filter((button) => !button.hide)) {
    if (wrapFn(btn, index, currentRow) && currentRow.length > 0) {
      result.push(currentRow)
      currentRow = []
    }
    currentRow.push(btn)
    index++
  }
  if (currentRow.length > 0) {
    result.push(currentRow)
  }
  return result
}

module.exports = Markup