feat: first entities in database

lib/bds/types/string_list.ex

@@ -0,0 +1,45 @@
+defmodule BDS.Types.StringList do
+  @moduledoc false
+
+  use Ecto.Type
+
+  def type, do: :string
+
+  def cast(value) when is_list(value) do
+    if Enum.all?(value, &is_binary/1) do
+      {:ok, value}
+    else
+      :error
+    end
+  end
+
+  def cast(nil), do: {:ok, []}
+  def cast(_value), do: :error
+
+  def load(nil), do: {:ok, []}
+
+  def load(value) when is_binary(value) do
+    case Jason.decode(value) do
+      {:ok, decoded} ->
+        if is_list(decoded) and Enum.all?(decoded, &is_binary/1) do
+          {:ok, decoded}
+        else
+          :error
+        end
+
+      _ -> :error
+    end
+  end
+
+  def dump(nil), do: {:ok, "[]"}
+
+  def dump(value) when is_list(value) do
+    if Enum.all?(value, &is_binary/1) do
+      {:ok, Jason.encode!(value)}
+    else
+      :error
+    end
+  end
+
+  def dump(_value), do: :error
+end