Update clawing of bears when a player claws

Whenever a player claws, a timer of 1000ms is set and every 50ms it will
decrease with 50ms until it becomes 0. During this time the bear's
'claw' will be true and it will be nil when it reaches 0. This is needed
to temporarily set a 'clawing' class on bears in the game.

apps/bear_necessities_web/lib/bear_necessities_web/live/game.ex

@@ -88,12 +88,16 @@ defmodule BearNecessitiesWeb.Game do
 
   def handle_event("key_up", key, %{id: id} = socket)
       when key in @arrow_keys do
-     Bear.stop(id)
+    Bear.stop(id)
     {:noreply, socket}
   end
 
   def handle_event("key_up", " ", %{id: id} = socket) do
-    Player.claw(id)
+    socket =
+      socket
+      |> assign(:bear, Player.claw(id))
+      |> assign(:viewport, ViewPort.get_viewport(id))
+
     {:noreply, socket}
   end
 
@@ -162,7 +166,7 @@ defmodule BearNecessitiesWeb.Game do
   def set_updates(false), do: nil
 
   def set_updates(true) do
-    {:ok, {:interval, ref}} = :timer.send_interval(50, self(), :update)
+    {:ok, ref} = :timer.send_interval(50, self(), :update)
     ref
   end
 

apps/game/lib/bear.ex

@@ -7,7 +7,8 @@ defmodule Bear do
             display_name: nil,
             started: false,
             direction: :down,
-            moving: false
+            moving: false,
+            clawing: false
 
   def create_bear(%{height: height, width: width}, id, display_name, started) do
     pos_x = Enum.random(0..height)

apps/game/lib/game.ex → apps/game/lib/game_server.ex

@@ -112,7 +112,7 @@ defmodule Game do
   @impl true
   def handle_call({:stop, id}, _pid, %{bears: bears} = state) do
     bear = get_bear_from_list(id, bears)
-    bear = %{bear | moving: false}
+    bear = %{bear | moving: false, clawing: false}
     state = update_state_with(state, bear)
 
     {:reply, bear, state}
@@ -124,6 +124,8 @@ defmodule Game do
         _pid,
         state
       ) do
+    bear = %{bear | clawing: true}
+
     {bear, state} =
       case target(direction, x, y, state) do
         %Tree{honey: tree_honey} = tree when tree_honey > 0 ->
@@ -153,13 +155,13 @@ defmodule Game do
           {new_bear, new_state}
 
         %Tree{honey: 0} ->
-          {bear, state}
+          {bear, update_state_with(state, bear)}
 
         %Bear{honey: 0} ->
-          {bear, state}
+          {bear, update_state_with(state, bear)}
 
         _ ->
-          {bear, state}
+          {bear, update_state_with(state, bear)}
       end
 
     {:reply, bear, state}

apps/game/lib/player.ex

@@ -2,19 +2,22 @@ defmodule Player do
   use GenServer
   require Logger
 
-  defstruct [:display_name, :score, :bear]
+  @claw_time_ms 1000
+
+  @enforce_keys [:id]
+  defstruct [:id, :claw, :timer_pid]
 
   def start_link(default) when is_list(default) do
     GenServer.start_link(__MODULE__, default, name: __MODULE__)
   end
 
   @impl true
-  def init([]) do
-    {:ok, []}
+  def init(id: id) do
+    {:ok, %Player{id: id}}
   end
 
   @impl true
-  def handle_call({:action, user_input, id}, _pid, _) do
+  def handle_call({:action, user_input, id}, _pid, state) do
     bear =
       case user_input do
         :up_arrow ->
@@ -30,14 +33,43 @@ defmodule Player do
           Bear.move(id, :right)
       end
 
-    {:reply, bear, []}
+    {:reply, bear, state}
   end
 
-  @imp true
-  def handle_call({:claw, id}, _pid, _) do
+  @impl true
+  def handle_call({:claw, id}, _pid, state) do
     bear = Bear.claw(id)
+    {:ok, timer_pid} = :timer.send_interval(50, self(), :update_claw)
+    state = %{state | claw: @claw_time_ms, timer_pid: timer_pid}
+
+    {:reply, bear, state}
+  end
+
+  @impl true
+  def handle_info(:update_claw, %{claw: nil} = state) do
+    {:noreply, state}
+  end
+
+  @impl true
+  def handle_info(:update_claw, %{claw: claw_time} = state) when claw_time > 0 do
+    state = %{state | claw: claw_time - 50}
+
+    {:noreply, state}
+  end
+
+  @impl true
+  def handle_info(:update_claw, %{id: id, claw: claw_time, timer_pid: timer_pid} = state)
+      when claw_time < 1 do
+    :timer.cancel(timer_pid)
+    state = %{state | claw: nil, timer_pid: nil}
+    Bear.stop(id)
+
+    {:noreply, state}
+  end
 
-    {:reply, bear, []}
+  @impl true
+  def handle_info(:update_claw, state) do
+    {:noreply, state}
   end
 
   def move(player_id, way) do
@@ -49,7 +81,7 @@ defmodule Player do
   end
 
   def start(display_name, id) do
-    Player.start_link([])
+    Player.start_link(id: id)
     Game.create_bear(display_name: display_name, id: id, started: true)
   end
 end