From 04f31a11597f470e1ba00b56a8d51d038aa2f2aa Mon Sep 17 00:00:00 2001
From: Yohann D'ANELLO <ynerant@crans.org>
Date: Mon, 21 Dec 2020 16:04:01 +0100
Subject: [PATCH] Better terminal refresh

Signed-off-by: Yohann D'ANELLO <ynerant@crans.org>
---
 squinnondation/squinnondation.py | 48 ++++++++++++++++++++------------
 squinnondation/term_manager.py   | 10 ++-----
 2 files changed, 32 insertions(+), 26 deletions(-)

diff --git a/squinnondation/squinnondation.py b/squinnondation/squinnondation.py
index d14ad67..387fa6f 100644
--- a/squinnondation/squinnondation.py
+++ b/squinnondation/squinnondation.py
@@ -50,29 +50,21 @@ class Squinnondation:
             screen = term_manager.screen
             screen.addstr(0, 0, "Enter your nickname: ")
             nickname = screen.getstr().decode("UTF-8")
+
             squirrel = Squirrel(nickname, instance.bind_address, instance.bind_port)
+            squirrel.refresh_history()
+            squirrel.refresh_input()
 
             if not instance.args.bind_only:
                 hazelnut = Hazelnut(address=instance.client_address, port=instance.client_port)
                 squirrel.hazelnuts[(instance.client_address, instance.client_port)] = hazelnut
 
-            squirrel.history = []
-
-            def refresh() -> None:
-                screen.clear()
-                screen.refresh()
-                for i, msg in enumerate(squirrel.history[max(0, len(squirrel.history) - curses.LINES + 2):]):
-                    screen.addstr(i, 0, msg)
-
-                screen.addstr(curses.LINES - 1, 0, f"<{squirrel.nickname}> ")
-                screen.refresh()
-            squirrel.refresh = refresh
-
             Worm(squirrel).start()
 
             while True:
-                refresh()
-                msg = screen.getstr().decode("UTF-8")
+                squirrel.refresh_history()
+                squirrel.refresh_input()
+                msg = screen.getstr(curses.LINES - 1, 3 + len(squirrel.nickname)).decode("UTF-8")
                 msg = f"<{squirrel.nickname}> {msg}"
                 squirrel.history.append(msg)
 
@@ -387,8 +379,12 @@ class Squirrel(Hazelnut):
         # Bind the socket
         self.socket.bind((str(self.address), self.port))
 
+        self.history = []
+        self.history_pad = curses.newpad(curses.LINES - 2, curses.COLS)
+        self.input_pad = curses.newpad(1, curses.COLS)
+
         self.hazelnuts = dict()
-        print(f"Listening on {self.address}:{self.port}")
+        self.history.append(f"<system> Listening on {self.address}:{self.port}")
 
     def find_hazelnut(self, address: str, port: int) -> Hazelnut:
         """
@@ -426,6 +422,23 @@ class Squirrel(Hazelnut):
         """
         return self.socket.recvfrom(1024)
 
+    def refresh_history(self) -> None:
+        """
+        Rewrite the history of the messages.
+        """
+        self.history_pad.erase()
+        for i, msg in enumerate(self.history[max(0, len(self.history) - curses.LINES + 2):]):
+            self.history_pad.addstr(i, 0, msg)
+        self.history_pad.refresh(0, 0, 0, 0, curses.LINES - 2, curses.COLS)
+
+    def refresh_input(self) -> None:
+        """
+        Redraw input line. Must not be called while the message is not sent.
+        """
+        self.input_pad.erase()
+        self.input_pad.addstr(0, 0, f"<{self.nickname}> ")
+        self.input_pad.refresh(0, 0, curses.LINES - 1, 0, curses.LINES - 1, curses.COLS - 1)
+
 
 class Worm(Thread):
     """
@@ -438,12 +451,11 @@ class Worm(Thread):
         self.squirrel = squirrel
 
     def run(self) -> None:
-        self.squirrel.history = []
         while True:
             try:
                 pkt, hazelnut = self.squirrel.receive_packet()
             except ValueError as error:
-                print("An error occured while receiving a packet: ", error)
+                self.squirrel.history.append("<system> An error occured while receiving a packet: {}".format(error))
             else:
                 self.squirrel.history.append(pkt.body[0].data.decode('UTF-8'))
-                self.squirrel.refresh()
+                self.squirrel.refresh_history()
diff --git a/squinnondation/term_manager.py b/squinnondation/term_manager.py
index 1005666..aba856e 100644
--- a/squinnondation/term_manager.py
+++ b/squinnondation/term_manager.py
@@ -14,12 +14,8 @@ class TermManager:  # pragma: no cover
         self.screen = curses.initscr()
         # convert escapes sequences to curses abstraction
         self.screen.keypad(True)
-        # stop printing typed keys to the terminal
-        # curses.noecho()
-        # send keys through without having to press <enter>
-        # curses.cbreak()
         # make cursor invisible
-        # curses.curs_set(False)
+        curses.curs_set(False)
         # Catch mouse events
         curses.mousemask(True)
         # Enable colors
@@ -32,7 +28,5 @@ class TermManager:  # pragma: no cover
                  exc_traceback: TracebackType) -> None:
         # restore the terminal to its original state
         self.screen.keypad(False)
-        # curses.echo()
-        # curses.nocbreak()
-        # curses.curs_set(True)
+        curses.curs_set(True)
         curses.endwin()