From 5b7f89707f0fe72f8306fa357f4369383dfb675c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C9=B4=E1=B4=8F=E1=B4=A0=E1=B4=80?=
 <146671001+ovnanova@users.noreply.github.com>
Date: Sat, 17 Feb 2024 12:01:35 -0800
Subject: [PATCH] Create didplc.ex

---
 lib/hexpds/didplc.ex | 68 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 68 insertions(+)
 create mode 100644 lib/hexpds/didplc.ex

diff --git a/lib/hexpds/didplc.ex b/lib/hexpds/didplc.ex
new file mode 100644
index 0000000..9cd4918
--- /dev/null
+++ b/lib/hexpds/didplc.ex
@@ -0,0 +1,68 @@
+defmodule Hexpds.DidPlc do
+  defmodule Operation do
+    defstruct [
+      :rotationKeys,
+      :prev,
+      :verificationMethods,
+      :alsoKnownAs,
+      :services,
+      type: "plc_operation"
+    ]
+
+    @type t :: %__MODULE__{
+            rotationKeys: [Hexpds.K256.PrivateKey.t()],
+            prev: String.t() | nil,
+            verificationMethods: VerificationMethods.t(),
+            alsoKnownAs: [String.t()],
+            services: Services.t(),
+            type: String.t()
+          }
+
+    defmodule VerificationMethods do
+      defstruct([:atproto])
+      @type t :: %__MODULE__{atproto: Hexpds.K256.PrivateKey.t()}
+    end
+
+    defmodule Services do
+      @type t :: %__MODULE__{atproto_pds: AtprotoPds.t()}
+      @derive Jason.Encoder
+      defstruct [:atproto_pds]
+
+      defmodule AtprotoPds do
+        @type t :: %__MODULE__{endpoint: String.t(), type: String.t()}
+        @derive Jason.Encoder
+        defstruct [:endpoint, type: "AtprotoPersonalDataServer"]
+      end
+    end
+
+    def genesis(
+          %Hexpds.K256.PrivateKey{} = rotationkey,
+          %Hexpds.K256.PrivateKey{} = signingkey,
+          handle,
+          pds
+        ) do
+      %__MODULE__{
+        rotationKeys: [rotationkey],
+        prev: nil,
+        verificationMethods: %Operation.VerificationMethods{atproto: signingkey},
+        alsoKnownAs: ["at://#{handle}"],
+        services: %Services{atproto_pds: %Services.AtprotoPds{endpoint: "https://#{pds}"}}
+      }
+    end
+
+    def to_json(%__MODULE__{} = operation) do
+      encodekeys = fn k ->
+        k |> Hexpds.K256.PrivateKey.to_pubkey() |> Hexpds.K256.PublicKey.to_did_key()
+      end
+
+      Jason.encode!(%{
+        "type" => operation.type,
+        "rotationKeys" => Enum.map(operation.rotationKeys, encodekeys),
+        "prev" => operation.prev,
+        "verificationMethods" => %{atproto: encodekeys.(operation.verificationMethods.atproto)},
+        "alsoKnownAs" => operation.alsoKnownAs,
+        "services" => operation.services
+      })
+    end
+  end
+end