From fff2e9efb0d0c6d14e91e8e0ec2b2cf28bd1835f Mon Sep 17 00:00:00 2001
From: ChillerDragon <ChillerDragon@gmail.com>
Date: Sun, 6 Nov 2022 20:08:32 +0100
Subject: [PATCH] First draft of sending inputs

Thanks a lot to @Swarfey for his tw-chatonly typescript package
https://www.npmjs.com/package/teeworlds

His simple calculation of the pred time was saving me a lot of time!
---
 lib/chunk.rb            | 15 ++++++++++
 lib/game_client.rb      | 41 +++++++++++++++++++++++++-
 lib/teeworlds-client.rb | 64 ++++++++++++++++++++++++++++++-----------
 3 files changed, 103 insertions(+), 17 deletions(-)

diff --git a/lib/chunk.rb b/lib/chunk.rb
index 750dcfd..a8f7917 100644
--- a/lib/chunk.rb
+++ b/lib/chunk.rb
@@ -34,6 +34,21 @@ class NetChunk
       "  data: #{str_hex(data)}"
   end
 
+  def self.create_non_vital_header(data = { size: 0 })
+    flag_bits = '00'
+    unused_bits = '00'
+
+    size_bits = data[:size].to_s(2).rjust(12, '0')
+    header_bits =
+      flag_bits +
+      size_bits[0..5] +
+      unused_bits +
+      size_bits[6..]
+    header_bits.chars.groups_of(8).map do |eigth_bits|
+      eigth_bits.join.to_i(2)
+    end
+  end
+
   ##
   # Create int array ready to be send over the network
   #
diff --git a/lib/game_client.rb b/lib/game_client.rb
index 12193ae..ce1cc3b 100644
--- a/lib/game_client.rb
+++ b/lib/game_client.rb
@@ -33,11 +33,13 @@ class Context
 end
 
 class GameClient
-  attr_accessor :players
+  attr_accessor :players, :pred_game_tick, :ack_game_tick
 
   def initialize(client)
     @client = client
     @players = {}
+    @ack_game_tick = -1
+    @pred_game_tick = 0
   end
 
   def on_client_info(chunk)
@@ -115,6 +117,43 @@ class GameClient
     @client.hooks[:rcon_line]&.call(context)
   end
 
+  def on_snapshot(chunk)
+    u = Unpacker.new(chunk.data)
+    u.get_int
+    # msg = u.get_int
+    # msg >>= 1
+
+    # num_parts = 1
+    # part = 0
+    game_tick = u.get_int
+    # delta_tick = u.get_int
+    # part_size = 0
+    # crc = 0
+    # complete_size = 0
+    # data = nil
+
+    # TODO: state check
+
+    # if msg == NETMSG_SNAP
+    #   num_parts = u.get_int
+    #   part = u.get_int
+    # end
+
+    # unless msg == NETMSG_SNAPEMPTY
+    #   crc = u.get_int
+    #   part_size = u.get_int
+    # end
+
+    # TODO: add get_raw(size)
+    # data = u.get_raw
+
+    # ack every snapshot no matter how broken
+    @ack_game_tick = game_tick
+    return unless (@pred_game_tick - @ack_game_tick).abs > 10
+
+    @pred_game_tick = @ack_game_tick + 1
+  end
+
   def on_emoticon(chunk); end
 
   def on_map_change(chunk)
diff --git a/lib/teeworlds-client.rb b/lib/teeworlds-client.rb
index 1cd28a8..b0299ff 100755
--- a/lib/teeworlds-client.rb
+++ b/lib/teeworlds-client.rb
@@ -77,6 +77,10 @@ class TeeworldsClient
     @hooks[:rcon_line] = block
   end
 
+  def on_on_snapshot(&block)
+    @hooks[:snapshot] = block
+  end
+
   def send_chat(str)
     @netbase.send_packet(
       NetChunk.create_vital_header({ vital: true }, 4 + str.length) +
@@ -256,18 +260,37 @@ class TeeworldsClient
   end
 
   def send_input
-    header = [0x10, 0x0A, 0o1] + str_bytes(@token)
-    random_compressed_input = [
-      0x4D, 0xE9, 0x48, 0x13, 0xD0, 0x0B, 0x6B, 0xFC, 0xB7, 0x2B, 0x6E, 0x00, 0xBA
-    ]
-    # this wont work we need to ack the ticks
-    # and then compress it
-    # CMsgPacker Msg(NETMSG_INPUT, true);
-    # Msg.AddInt(m_AckGameTick);
-    # Msg.AddInt(m_PredTick);
-    # Msg.AddInt(Size);
-    msg = header + random_compressed_input
-    @s.send(msg.pack('C*'), 0, @ip, @port)
+    inp = {
+      direction: -1,
+      target_x: 10,
+      target_y: 10,
+      jump: rand(0..1),
+      fire: 0,
+      hook: 0,
+      player_flags: 0,
+      wanted_weapon: 0,
+      next_weapon: 0,
+      prev_weapon: 0
+    }
+
+    data = []
+    data += Packer.pack_int(@game_client.ack_game_tick)
+    data += Packer.pack_int(@game_client.pred_game_tick)
+    data += Packer.pack_int(40) # magic size 40
+    data += Packer.pack_int(inp[:direction])
+    data += Packer.pack_int(inp[:target_x])
+    data += Packer.pack_int(inp[:target_y])
+    data += Packer.pack_int(inp[:jump])
+    data += Packer.pack_int(inp[:fire])
+    data += Packer.pack_int(inp[:hook])
+    data += Packer.pack_int(inp[:player_flags])
+    data += Packer.pack_int(inp[:wanted_weapon])
+    data += Packer.pack_int(inp[:next_weapon])
+    data += Packer.pack_int(inp[:prev_weapon])
+    msg = NetChunk.create_non_vital_header(size: data.size + 1) +
+          [pack_msg_id(NETMSG_INPUT, system: true)] +
+          data
+    @netbase.send_packet(msg, 1)
   end
 
   def on_msg_token(data)
@@ -331,6 +354,8 @@ class TeeworldsClient
       # should we be in alert here?
     when NETMSG_RCON_LINE
       @game_client.on_rcon_line(chunk)
+    when NETMSG_SNAP, NETMSG_SNAPSINGLE, NETMSG_SNAPEMPTY
+      @game_client.on_snapshot(chunk)
     else
       puts "Unsupported system msg: #{chunk.msg}"
       exit(1)
@@ -385,11 +410,18 @@ class TeeworldsClient
       process_server_packet(packet)
     end
 
-    @ticks += 1
     send_ctrl_keepalive if (@ticks % 8).zero?
-    # if @ticks % 20 == 0
-    #   send_chat("hello world")
-    # end
+    if @game_client.ack_game_tick.positive?
+      now = Time.now
+      @@last_pred ||= now
+      diff = now - @@last_pred
+      # @Swarfey does js setInterval(20) in his lib
+      # not sure if it makes sense to do a diff > 0.2 here then xd
+      @game_client.pred_game_tick += 1 if diff > 0.2
+    end
+
+    @ticks += 1
+    send_input if (@ticks % 20).zero?
   end
 
   def connection_loop