+ currency config

include/parse_config.ml

@@ -205,14 +205,14 @@ let get t ~section ~field =
   | None -> fail_with (Fmt.str "option `[%s].%s` not found" section field)
   | Some v -> v
 
-let int v =
-  match int_of_string_opt v with
-  | None -> fail_with (Fmt.str "expected int value, got `%s`" v)
+let int s =
+  match int_of_string_opt s with
+  | None -> fail_with (Fmt.str "expected int value, got `%s`" s)
   | Some v -> v
 
-let float v =
-  match float_of_string_opt v with
-  | None -> fail_with (Fmt.str "expected float value, got `%s`" v)
+let float s =
+  match float_of_string_opt s with
+  | None -> fail_with (Fmt.str "expected float value, got `%s`" s)
   | Some v -> v
 
 let const_value a b =
@@ -225,19 +225,62 @@ let yes_no = function
   | "YES" -> `YES
   | s -> fail_with (Fmt.str "expected `YES`/`NO` value, got `%s`" s)
 
-let amount v = v |> Amount.of_string |> unwrap_res
-let duration v = Parse_duration.(v |> parse |> to_ptime_span)
+let amount s = s |> Amount.of_string |> unwrap_res
+let duration s = Parse_duration.(s |> parse |> to_ptime_span)
 
-let ed25519 v =
-  v
+let ed25519 s =
+  s
   |> B32.decode
   |> unwrap_res
   |> Mirage_crypto_ec.Ed25519.pub_of_octets
   |> Result.map_error (fun e -> Fmt.str "%a" Mirage_crypto_ec.pp_error e)
   |> unwrap_res
 
+module Parse_alt_unit_names = struct
+  let rm_brackets s =
+    let s = String.trim s in
+    match
+      String.starts_with ~prefix:"{" s && String.ends_with ~suffix:"}" s
+    with
+    | false -> fail_with (Fmt.str "expected json, got `%s`" s)
+    | true ->
+        let s = String.sub s 1 (String.length s - 2) in
+        s
+
+  let rm_quotes s =
+    let s = String.trim s in
+    match
+      String.starts_with ~prefix:"\"" s && String.ends_with ~suffix:"\"" s
+    with
+    | false -> fail_with (Fmt.str "expected quoted string, got `%s`" s)
+    | true ->
+        let s = String.sub s 1 (String.length s - 2) in
+        s
+
+  let parse s =
+    let s = rm_brackets s in
+    String.split_on_char ',' s
+    |> List.map (String.split_on_char ':')
+    |> List.map (function
+      | [ k; v ] -> (k, v)
+      | _ -> fail_with "invalid json key-value map")
+    |> List.map (fun (k, v) ->
+        let k = rm_quotes k in
+        let v = rm_quotes v in
+        let k =
+          match int_of_string_opt k with
+          | None ->
+              fail_with
+                (Fmt.str
+                   "invalid json key-value map, expected integer key, got `%s`"
+                   k)
+          | Some k -> k
+        in
+        (k, v))
+end
+
 module Config = struct
-  [@@@ocaml.warning "-32"]
+  [@@@ocaml.warning "-32-69"]
 
   let config =
     let read_file file = In_channel.with_open_bin file In_channel.input_all in
@@ -312,4 +355,58 @@ module Config = struct
     let max_aml_program_runtime = get "max_aml_program_runtime" |> duration
     let default_purse_limit = get "default_purse_limit" |> int
   end
+
+  module Currency = struct
+    type t = {
+      enabled: [ `YES | `NO ];
+      code: string;
+      name: string;
+      fractional_input_digits: int;
+      fractional_normal_digits: int;
+      fractional_trailing_zero_digits: int;
+      alt_unit_names: (int * string) list;
+    }
+
+    let currency_sections =
+      List.filter_map
+        (fun v ->
+          match String.starts_with ~prefix:"currency-" v.header with
+          | false -> None
+          | true -> Some v)
+        config
+
+    let parse_currency section =
+      let get field = get config ~section:section.header ~field in
+      {
+        enabled= get "enabled" |> yes_no;
+        code= get "code";
+        name= get "name";
+        fractional_input_digits= get "fractional_input_digits" |> int;
+        fractional_normal_digits= get "fractional_normal_digits" |> int;
+        fractional_trailing_zero_digits=
+          get "fractional_trailing_zero_digits" |> int;
+        alt_unit_names= get "alt_unit_names" |> Parse_alt_unit_names.parse;
+      }
+
+    let all_currencies = List.map parse_currency currency_sections
+
+    (* I think the exchange only handle one currency *)
+    let v =
+      match
+        List.find_opt (fun v -> v.code = Exchange.currency) all_currencies
+      with
+      | None ->
+          fail_with
+            (Fmt.str
+               "section `[currency-%s]` not found, currency `%s` is not defined"
+               Exchange.currency Exchange.currency)
+      | Some v -> v
+
+    (*
+    let () =
+      let pp_pair ppf (k, v) = Fmt.pf ppf "k: %d - v: %s" k v in
+      Fmt.epr "alt unit names:@\n%a@." (Fmt.list pp_pair) v.alt_unit_names;
+      ()
+      *)
+  end
 end