add favorite

1 files changed, 73 insertions, 0 deletions

diff --git a/public/javascripts/favorite.js b/public/javascripts/favorite.js
new file mode 100644
index 0000000..f10d954
--- /dev/null
+++ b/public/javascripts/favorite.js
@@ -0,0 +1,73 @@
+/* global USERS */
+
+const EventEmitter = require('events')
+
+const self = new EventEmitter()
+
+self._nodes = {
+  toggle: document.querySelector('.fav')
+}
+
+self.get = function () {
+  const localStorageUser = JSON.parse(window.localStorage.getItem('fav'))
+  if (localStorageUser == null) return
+
+  const correctedUser = USERS.filter(user =>
+      user.type === localStorageUser.type &&
+      user.value === localStorageUser.value)[0]
+  return correctedUser
+}
+
+self.set = function (user) {
+  window.localStorage.setItem('fav', JSON.stringify(user))
+  self._nodes.innerHTML = ''
+}
+
+self.delete = function () {
+  window.localStorage.removeItem('fav')
+}
+
+self.updateDom = function (isFavorite) {
+  if (isFavorite) {
+    self._nodes.toggle.innerHTML = ''
+  } else {
+    self._nodes.toggle.innerHTML = '&#xE83A'
+  }
+}
+
+self.update = function (selectedUser) {
+  const currentUser = self.get()
+
+  if (currentUser == null) {
+    self.updateDom(false)
+    return
+  }
+
+  const isEqual = currentUser.type === selectedUser.type &&
+                  currentUser.index === selectedUser.index
+
+  self.updateDom(isEqual)
+}
+
+self.toggle = function (selectedUser) {
+  const currentUser = self.get()
+  const isEqual = currentUser != null &&
+                  currentUser.type === selectedUser.type &&
+                  currentUser.index === selectedUser.index
+
+  if (isEqual) {
+    self.delete()
+    self.updateDom(false)
+  } else {
+    self.set(selectedUser)
+    self.updateDom(true)
+  }
+}
+
+self._handleClick = function () {
+  self.emit('click')
+}
+
+self._nodes.toggle.addEventListener('click', self._handleClick)
+
+module.exports = self