From b7ec2f599e93d402130bc3edd48ee31724b2ee86 Mon Sep 17 00:00:00 2001
From: Ashlynne Mitchell <ovy@ovyerus.com>
Date: Wed, 11 Mar 2026 23:15:17 +1100
Subject: [PATCH] feat(deflexicon): wip

---
 CHANGELOG.md        |  2 ++
 lib/atex/lexicon.ex | 38 ++++++++++++++++++++++++++++++++++++--
 2 files changed, 38 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 99112c9..4052c18 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -37,6 +37,8 @@ and this project adheres to
 - Various improvements to `Atex.Did.Document`
   - Add `Atex.DID.Document.Service` and `Atex.DID.Document.VerificationMethod` sub-structs.
   - Add `to_json/1` methods and `JSON.Encoder` protocols for easy conversion to camelCase JSON.
+- `deflexicon` now emits `content_type/0` functions (on `Input` submodules for typed JSON bodies,
+  otherwise on the root module) for procedures.
 
 ### Fixed
 
diff --git a/lib/atex/lexicon.ex b/lib/atex/lexicon.ex
index 6da755e..75e7e90 100644
--- a/lib/atex/lexicon.ex
+++ b/lib/atex/lexicon.ex
@@ -347,8 +347,26 @@ defmodule Atex.Lexicon do
 
     input =
       if def[:input] && def.input[:schema] do
-        [schema] = def_to_schema(nsid, "input", def.input.schema)
-        schema
+        encoding = def.input[:encoding]
+
+        [{key, quoted_schema, quoted_type, quoted_struct}] =
+          def_to_schema(nsid, "input", def.input.schema)
+
+        quoted_struct =
+          quote do
+            unquote(quoted_struct)
+
+            @spec content_type() :: String.t()
+            def content_type, do: unquote(encoding)
+          end
+
+        {key, quoted_schema, quoted_type, quoted_struct}
+      end
+
+    # Add `content_type/0` to the root module if the lexicon defines a type without a schema.
+    raw_input_encoding =
+      if is_nil(input) && def[:input] do
+        def.input[:encoding]
       end
 
     # Root struct containing `input`, `raw_input`, and `params`
@@ -388,6 +406,22 @@ defmodule Atex.Lexicon do
               defstruct input: nil
             end
 
+          params && raw_input_encoding ->
+            quote do
+              defstruct raw_input: nil, params: nil
+
+              @spec content_type() :: String.t()
+              def content_type, do: unquote(raw_input_encoding)
+            end
+
+          raw_input_encoding ->
+            quote do
+              defstruct raw_input: nil
+
+              @spec content_type() :: String.t()
+              def content_type, do: unquote(raw_input_encoding)
+            end
+
           params ->
             quote do
               defstruct raw_input: nil, params: nil
-- 
2.51.2