Add submission URLs and fave toggling functions

Submission.py

@@ -27,6 +27,10 @@ class Submission:
         self._faves: int = None
         self._comments: List[Comment.Comment] = None
         self._views: int = None
+        self._preview_url: str = None
+        self._download_url: str = None
+        self._faved: bool = None
+        self._fave_url: str = None
 
     @property
     def url(self):
@@ -119,6 +123,35 @@ class Submission:
 
         return self._views
 
+    @property
+    def preview_url(self):
+        if not self._preview_url:
+            self._get_submission()
+
+        return self._preview_url
+
+    @property
+    def download_url(self):
+        if not self._download_url:
+            self._get_submission()
+
+        return self._download_url
+
+    @property
+    def faved(self):
+        if self._faved is None:
+            self._get_submission()
+
+        return self._faved
+
+    def fave(self):
+        if self.faved is False:  # Usage of the faved property is deliberate to ensure _get_submission() has run
+            self._toggle_fave()
+
+    def unfave(self):
+        if self.faved is True:  # Usage of the faved property is deliberate to ensure _get_submission() has run
+            self._toggle_fave()
+
     def _get_submission(self):
         soup = self._api.get_soup('{}/view/{}'.format(FAAPI.FA_BASE_URL, self.id))
 
@@ -134,6 +167,10 @@ class Submission:
         self._gender = soup.select('.info div:nth-of-type(3) span')[0].text.strip()
         self._faves = int(soup.select('.favorites .font-large')[0].text.strip())
         self._views = int(soup.select('.views .font-large')[0].text.strip())
+        self._preview_url = 'https:' + soup.select('#submissionImg')[0].get('data-preview-src')
+        self._download_url = 'https:' + soup.select('#submissionImg')[0].get('data-fullview-src')
+        self._faved = '-' in soup.select('.fav')[0].text
+        self._fave_url = FAAPI.FA_BASE_URL + soup.select('.fav a')[0].get('href')
 
         # Parse comments
         self._comments = []
@@ -168,5 +205,11 @@ class Submission:
 
             self._comments.append(comment)
 
+    def _toggle_fave(self):
+        soup = self._api.get_soup(self._fave_url)
+
+        self._faved = '-' in soup.select('.fav')[0].text
+        self._fave_url = FAAPI.FA_BASE_URL + soup.select('.fav a')[0].get('href')
+
     def __str__(self):
         return '{} - {} ({}/view/{})'.format(self.author, self.title, self.url)