Re-add spam filtering, improve length marquee limiting

4 files changed, 95 insertions, 73 deletions

diff --git a/.gitignore b/.gitignore
index cc23a6b..7873606 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,2 @@
 firmware/gcc/*
+host/secret_sauce.py
diff --git a/host/bdf.py b/host/bdf.py
index a8fc8f3..fb4c928 100644
--- a/host/bdf.py
+++ b/host/bdf.py
@@ -40,7 +40,7 @@ class Font:
 		textw, texth = c_size_t(0), c_size_t(0)
 		res = lib.framebuffer_get_text_bounds(textbytes, self.font, byref(textw), byref(texth))
 		if res:
-			raise ValueError('Invalid text')
+			raise RuntimeError('Invalid text')
 		return textw.value, texth.value
 
 	def render_text(self, text, offset):
@@ -49,7 +49,7 @@ class Font:
 			res = lib.framebuffer_render_text(textbytes, self.font, self.cbuf,
 					config.display_width, config.display_height, offset)
 			if res:
-				raise ValueError('Invalid text')
+				raise RuntimeError('Invalid text')
 			return self.cbuf
 
 unifont = Font()
diff --git a/host/config.py b/host/config.py
index 02a047c..b76e2aa 100644
--- a/host/config.py
+++ b/host/config.py
@@ -44,3 +44,7 @@ crap_fw_addr, crap_fw_port = '127.0.0.1', 1338
 # USB Serial number of matelight to control as byte string (None for first matelight connected)
 ml_usb_serial_match = None
 
+# Maximum width allowed for marquee texts in px. For reference: Using GNU unifont, a normal (half-width) char such as ∀
+# is 8px wide, a full-width char such as 水 is 16px wide.
+max_marquee_width = 140*8
+
diff --git a/host/server.py b/host/server.py
index f83e2cd..e622d9b 100755
--- a/host/server.py
+++ b/host/server.py
@@ -4,9 +4,12 @@ import socket
 import time
 import itertools
 import sys
+import re
 from contextlib import suppress
 import asyncio
 import threading
+import functools
+import operator
 
 import config
 
@@ -14,86 +17,100 @@ import matelight
 import bdf
 import crap
 
+import secret_sauce
+
 
 def log(*args):
-	print(time.strftime('\x1B[93m[%m-%d %H:%M:%S]\x1B[0m'), ' '.join(str(arg) for arg in args), '\x1B[0m')
-	sys.stdout.flush()
+    print(time.strftime('\x1B[93m[%m-%d %H:%M:%S]\x1B[0m'), ' '.join(str(arg) for arg in args), '\x1B[0m')
+    sys.stdout.flush()
 
-class TextRenderer:
-	def __init__(self, text, title='default', font=bdf.unifont):
-		self.text = text
-		self.font = font
-		(self.width, _), _testrender  = font.compute_text_bounds(text), font.render_text(text, 0)
-		self.title = title
+def addrcolor(addr):
+    col = 16 + (functools.reduce(operator.xor, (int(e or '0') for e in re.split('[.:]', addr))) % 216)
+    return '\x1B[38;5;{}m{}\x1B[0m'.format(col, addr)
 
-	def __iter__(self):
-		for i in range(-config.display_width, self.width):
-			yield self.title, self.font.render_text(self.text, i)
-			time.sleep(0.05)
+
+class TextRenderer:
+    def __init__(self, text, title='default', checkwidth=False, font=bdf.unifont):
+        self.text = text
+        self.font = font
+        (self.width, _), _testrender  = font.compute_text_bounds(text), font.render_text(text, 0)
+        self.title = title
+        if self.width > config.max_marquee_width:
+            raise ValueError()
+
+    def __iter__(self):
+        for i in range(-config.display_width, self.width):
+            yield self.title, self.font.render_text(self.text, i)
+            time.sleep(0.05)
 
 class MatelightTCPServer:
-	def __init__(self, ip, port, loop):
-		coro = asyncio.start_server(self.handle_conn, ip, port, loop=loop)
-		server = loop.run_until_complete(coro)
-		self.renderqueue = []
-		self.close = server.close
-
-	def __iter__(self):
-		q, self.renderqueue = self.renderqueue, []
-		for title, frame in itertools.chain(*q):
-			yield title, frame
-
-	async def handle_conn(self, reader, writer):
-		line = (await reader.read(1024)).decode('UTF-8').strip()
-		if len(line) > 140: # Unicode string length, *not* byte length of encoded UTF-8
-			writer.write(b'TOO MUCH INFORMATION!\n')
-		else:
-			addr,*rest = writer.get_extra_info('peername')
-			log('\x1B[95mText from\x1B[0m {}: {}\x1B[0m'.format(addr, line))
-			try:
-				self.renderqueue.append(TextRenderer(line, title='tcp:'+addr))
-			except:
-				writer.write(b'STAHPTROLLINK?\n')
-			else:
-				writer.write(b'KTHXBYE!\n')
-		await writer.drain()
-		writer.close()
+    def __init__(self, ip, port, loop):
+        coro = asyncio.start_server(self.handle_conn, ip, port, loop=loop)
+        server = loop.run_until_complete(coro)
+        self.renderqueue = []
+        self.close = server.close
+
+    def __iter__(self):
+        q, self.renderqueue = self.renderqueue, []
+        for title, frame in itertools.chain(*q):
+            yield title, frame
+
+    async def handle_conn(self, reader, writer):
+        line = (await reader.read(1024)).decode('UTF-8').strip()
+        addr,*rest = writer.get_extra_info('peername')
+
+        log('\x1B[95mText from\x1B[0m {}: {}\x1B[0m'.format(addrcolor(addr), line))
+        try:
+            secret_sauce.check_spam(str(addr), line)
+            renderer = TextRenderer(line, title='tcp:'+addr, checkwidth=True)
+        except secret_sauce.SpamError as err:
+            log('\x1B[91mMessage rejected from {}: {}'.format(addrcolor(addr), err))
+            writer.write(b'BLERGH!\n')
+        except ValueError: # Text too long
+            writer.write(b'TOO MUCH INFORMATION!\n')
+        except RuntimeError: # Invalid escape etc.
+            writer.write(b'STAHPTROLLINK?\n')
+        else:
+            self.renderqueue.append(renderer)
+            writer.write(b'KTHXBYE!\n')
+        await writer.drain()
+        writer.close()
 
 def _fallbackiter(it, fallback):
-	for fel in fallback:
-		for el in it:
-			yield el
-		yield fel
+    for fel in fallback:
+        for el in it:
+            yield el
+        yield fel
 
 def defaulttexts(filename='default.lines'):
-	with open(filename) as f:
-		return itertools.chain.from_iterable(( TextRenderer(l[:-1].replace('\\x1B', '\x1B')) for l in f.readlines() ))
+    with open(filename) as f:
+        return itertools.chain.from_iterable(( TextRenderer(l[:-1].replace('\\x1B', '\x1B')) for l in f.readlines() ))
 
 if __name__ == '__main__':
-	try:
-		ml = matelight.Matelight(config.ml_usb_serial_match)
-	except ValueError as e:
-		print(e, 'Starting in headless mode.', file=sys.stderr)
-		ml = None
-
-	loop = asyncio.get_event_loop()
-
-	tcp_server = MatelightTCPServer(config.tcp_addr, config.tcp_port, loop)
-	udp_server = crap.CRAPServer(config.udp_addr, config.udp_port)
-	forwarder  = crap.CRAPClient(config.crap_fw_addr, config.crap_fw_port) if config.crap_fw_addr is not None else None
-
-	async_thr = threading.Thread(target=loop.run_forever)
-	async_thr.daemon = True
-	async_thr.start()
-
-	with suppress(KeyboardInterrupt):
-		while True:
-			for title, frame in _fallbackiter(udp_server, _fallbackiter(tcp_server, defaulttexts())):
-				if ml:
-					ml.sendframe(frame)
-				if forwarder:
-					forwarder.sendframe(frame)
-
-	tcp_server.close()
-	udp_server.close()
-	forwarder.close()
+    try:
+        ml = matelight.Matelight(config.ml_usb_serial_match)
+    except ValueError as e:
+        print(e, 'Starting in headless mode.', file=sys.stderr)
+        ml = None
+
+    loop = asyncio.get_event_loop()
+
+    tcp_server = MatelightTCPServer(config.tcp_addr, config.tcp_port, loop)
+    udp_server = crap.CRAPServer(config.udp_addr, config.udp_port)
+    forwarder  = crap.CRAPClient(config.crap_fw_addr, config.crap_fw_port) if config.crap_fw_addr is not None else None
+
+    async_thr = threading.Thread(target=loop.run_forever)
+    async_thr.daemon = True
+    async_thr.start()
+
+    with suppress(KeyboardInterrupt):
+        while True:
+            for title, frame in _fallbackiter(udp_server, _fallbackiter(tcp_server, defaulttexts())):
+                if ml:
+                    ml.sendframe(frame)
+                if forwarder:
+                    forwarder.sendframe(frame)
+
+    tcp_server.close()
+    udp_server.close()
+    forwarder.close()