add paging

hn.py

@@ -89,10 +89,18 @@ class Client:
             self.cursor_pos -= 1
             if self.cursor_pos < 0:
                 self.cursor_pos = self.stories_in_a_site-1
+                # scroll up a page (:
+                self.story_pos -= self.stories_in_a_site
+                self.story_pos = 0 if self.story_pos < 0 else self.story_pos
+
         elif c == curses.KEY_DOWN:
             self.cursor_pos += 1
             if self.cursor_pos >= self.stories_in_a_site:
                 self.cursor_pos = 0
+                # scroll up down a page :)
+                self.story_pos += self.stories_in_a_site
+                self.load_more_if_needed()
+
         elif c == ord('c'):
             webbrowser.open(f'https://news.ycombinator.com/item?id={self.loadedstories[self.story_pos + self.cursor_pos].id}')
         elif c == curses.KEY_ENTER or c == 10:
@@ -101,6 +109,9 @@ class Client:
             curses.resize_term(*self.screen.getmaxyx())
             self.lines, self.cols = self.screen.getmaxyx()
             self.stories_in_a_site = self.lines - 3
+            self.load_more_if_needed()
+
+    def load_more_if_needed(self):
         if len(self.loadedstories) < self.story_pos + self.stories_in_a_site:
             # load more
             self.load_stories(len(self.loadedstories), self.story_pos + self.stories_in_a_site)