lab 02 Q1

labs/02/card_server.ex

@@ -0,0 +1,71 @@
+defmodule CardServer do
+  # --- Server Implementation ---
+  def start() do
+    spawn(fn -> loop(new()) end)
+  end
+
+  defp new() do
+    values = Enum.map(2..10, &Integer.to_string/1) ++ ["J", "Q", "K", "A"]
+    suits  = ["\u2663", "\u2666", "\u2665", "\u2660"]
+
+    for v <- values, f <- suits, do: v <> f
+  end
+
+  defp deal(from, deck, n) do
+    case n do
+      _ when n < 0 ->
+        send(from, {:error, "Cannot deal negative number of cards"})
+        deck
+
+      _ when n > length(deck) ->
+        send(from, {:error, "Insufficient cards in deck to deal"})
+        deck
+
+      _ ->
+        {d, r} = Enum.split(deck, n)
+        send(from, {:ok, d})
+        r
+    end
+  end
+
+  defp loop(deck) do
+    receive do
+      :new ->
+        loop(new())
+
+      :shuffle ->
+        loop(Enum.shuffle(deck))
+
+      {from, :count} ->
+        send(from, length(deck))
+        loop(deck)
+
+      {from, :deal, n} ->
+        remaining = deal(from, deck, n)
+        loop(remaining)
+    end
+  end
+
+  # --- Client API ---
+  def new(pid) do
+    send(pid, :new)
+  end
+
+  def shuffle(pid) do
+    send(pid, :shuffle)
+  end
+
+  def count(pid) do
+    send(pid, {self(), :count})
+    receive do
+      x -> x
+    end
+  end
+
+  def deal(pid, n \\ 1) do
+    send(pid, {self(), :deal, n})
+    receive do
+      x -> x
+    end
+  end
+end