From 0e965eccc888d307ce7974f5ad2fcd9c69347c0e Mon Sep 17 00:00:00 2001
From: swrup <swrup@protonmail.com>
Date: Mon, 23 Feb 2026 09:02:39 +0100
Subject: [PATCH]

---
 src/denomination.ml | 73 ++++++++++++++++++++++++++++++++++++++
 src/http_info.ml    | 85 ++++++++++++---------------------------------
 2 files changed, 96 insertions(+), 62 deletions(-)

diff --git a/src/denomination.ml b/src/denomination.ml
index 28622e9c..ec5f7905 100644
--- a/src/denomination.ml
+++ b/src/denomination.ml
@@ -15,3 +15,76 @@ type t = {
   h_pub: denom_hash;
   master_sig: Signatures.DenominationKeyValidity.t;
 }
+
+let make_denom_group denominations =
+  let open Syntax in
+  let ht = Hashtbl.create 0xff in
+  List.iter
+    (fun coin ->
+      let open Config.Coin in
+      assert (coin.cipher = `RSA);
+      let k =
+        ( coin.value,
+          coin.fee_withdraw,
+          coin.fee_deposit,
+          coin.fee_refresh,
+          coin.fee_refund )
+      in
+      let v = [] in
+      Hashtbl.replace ht k v)
+    Config.Coin.all_coins;
+  let+ () =
+    list_iter
+      (fun {
+             pub;
+             value;
+             stamp_start;
+             stamp_expire_withdraw;
+             stamp_expire_deposit;
+             stamp_expire_legal;
+             fee_withdraw;
+             fee_deposit;
+             fee_refresh;
+             fee_refund;
+             age_mask= _;
+             h_pub= _;
+             master_sig;
+           } ->
+        let k = (value, fee_withdraw, fee_deposit, fee_refresh, fee_refund) in
+        let v =
+          Api.RsaDenom.
+            {
+              rsa_pub= pub;
+              master_sig;
+              stamp_start;
+              stamp_expire_withdraw;
+              stamp_expire_deposit;
+              stamp_expire_legal;
+              lost= None;
+            }
+        in
+        let+ l =
+          match Hashtbl.find_opt ht k with
+          | None ->
+              Error "denomination does not match any coin in configuration"
+          | Some l -> Ok l
+        in
+        Hashtbl.replace ht k (v :: l))
+      denominations
+  in
+  Hashtbl.to_seq ht
+  |> List.of_seq
+  |> List.map
+       (fun
+         ((value, fee_withdraw, fee_deposit, fee_refresh, fee_refund), denoms)
+       ->
+         Api.DenomGroup.Rsa
+           Api.RsaDenomGroup.
+             {
+               denoms;
+               value;
+               fee_withdraw;
+               fee_deposit;
+               fee_refresh;
+               fee_refund;
+             })
diff --git a/src/http_info.ml b/src/http_info.ml
index f7043ff8..e2f5ee73 100644
--- a/src/http_info.ml
+++ b/src/http_info.ml
@@ -20,44 +20,6 @@ let config req _server _env =
   let res = Api.encode Api.ExchangeVersionResponse.jsont config in
   Respond.result res req
 
-(* TODO
-   for now we only have one item in each "denom group"
-   change this once we have denom/signkey rotation *)
-let denomgroup_of_denomdata
-    Denomination.
-      {
-        pub;
-        value;
-        stamp_start;
-        stamp_expire_withdraw;
-        stamp_expire_deposit;
-        stamp_expire_legal;
-        fee_withdraw;
-        fee_deposit;
-        fee_refresh;
-        fee_refund;
-        age_mask= _;
-        h_pub= _;
-        master_sig;
-      } =
-  let denoms =
-    [
-      RsaDenom.
-        {
-          rsa_pub= pub;
-          master_sig;
-          stamp_start;
-          stamp_expire_withdraw;
-          stamp_expire_deposit;
-          stamp_expire_legal;
-          lost= None;
-        };
-    ]
-  in
-  DenomGroup.Rsa
-    RsaDenomGroup.
-      { denoms; value; fee_withdraw; fee_deposit; fee_refresh; fee_refund }
-
 let mk_keys ~db_conn (module Keys : Keys.S) ~last_issue_date =
   let version = Api.protocol_version in
   let base_url = Config.base_url in
@@ -96,40 +58,39 @@ let mk_keys ~db_conn (module Keys : Keys.S) ~last_issue_date =
   let wallet_balance_limit_without_kyc = None in
   let hard_limits = [] in
   let zero_limits = [] in
-  let* dn_l =
-    let+ l = Keys.denominations () in
+  let* denom_l = Keys.denominations () in
+  let denom_l =
     (* reverse chronological order *)
     List.sort
       (fun a b -> Stdlib.compare b.Denomination.stamp_start a.stamp_start)
-      l
+      denom_l
   in
   let list_issue_date =
-    match dn_l with
+    match denom_l with
     | [] -> Timestamp.never
     | dn :: _ -> dn.Denomination.stamp_start
   in
-  let denominations =
+  let denom_l =
     (* if `?last_issue_date` query param does not exactly match the `stamp_start`
        of one of the denomination keys, all keys are returned *)
-    let open Denomination in
-    let l =
-      match last_issue_date with
-      | None -> dn_l
-      | Some last_issue_date -> (
-          match
-            List.find_opt
-              (fun v -> Timestamp.compare v.stamp_start last_issue_date = 0)
-              dn_l
-          with
-          | None -> dn_l
-          | Some _ ->
-              List.filter
-                (fun v ->
-                  Time.Timestamp.compare v.stamp_start last_issue_date >= 0)
-                dn_l)
-    in
-    List.map denomgroup_of_denomdata l
+    match last_issue_date with
+    | None -> denom_l
+    | Some last_issue_date -> (
+        match
+          List.find_opt
+            (fun v ->
+              Timestamp.compare v.Denomination.stamp_start last_issue_date = 0)
+            denom_l
+        with
+        | None -> denom_l
+        | Some _ ->
+            List.filter
+              (fun v ->
+                Timestamp.compare v.Denomination.stamp_start last_issue_date
+                >= 0)
+              denom_l)
   in
+  let* denominations = Denomination.make_denom_group denom_l in
 
   let* signkeys =
     let+ l = Keys.signkeys () in
@@ -151,7 +112,7 @@ let mk_keys ~db_conn (module Keys : Keys.S) ~last_issue_date =
        contatentation of all of the master_sigs (in reverse
        chronological order by group) in the arrays under "denominations". *)
     let hc =
-      dn_l
+      denom_l
       |> List.map (fun dn -> dn.Denomination.master_sig)
       |> List.map Signatures.DenominationKeyValidity.to_octets
       |> String.concat ""