From a6fd15c1b1907b2dcec7363e6e5789071ab8dbfb Mon Sep 17 00:00:00 2001
From: Yehowshua Immanuel <yehowshua@joyofhardware.com>
Date: Thu, 2 Jan 2025 11:33:01 -0500
Subject: [PATCH] good stopping point - backend now pushes updates to frontend
 in consistent JSON format

---
 backend/src/main.rs           | 21 +++++++++++++++++----
 frontend/src/Page/Landing.elm | 26 +++++++++-----------------
 2 files changed, 26 insertions(+), 21 deletions(-)

diff --git a/backend/src/main.rs b/backend/src/main.rs
index 56bb0ed..929de35 100644
--- a/backend/src/main.rs
+++ b/backend/src/main.rs
@@ -5,8 +5,8 @@ use actix_web_actors::ws;
 use log::info;
 use serde::{Deserialize, Serialize};
 use std::{fs, time::Duration};
+use chrono::Local;
 
-mod landing;
 
 /// Greeting API structures
 #[derive(Serialize, Deserialize)]
@@ -19,9 +19,14 @@ struct GreetingResponse {
     message: String,
 }
 
+#[derive(Serialize)]
+pub struct Landing {
+    pub time : String
+}
+
 #[derive(Serialize)]
 enum ToFrontend {
-    Landing(landing::Landing)
+    Landing(Landing)
 }
 
 async fn greet(req: web::Json<GreetingRequest>) -> impl Responder {
@@ -40,8 +45,16 @@ impl Actor for MyWebSocket {
         info!("WebSocket actor started");
         // Send messages every second
         ctx.run_interval(Duration::from_secs(1), |_, ctx| {
-            let message = format!("{{\"time\" : \"{:?}\" }}", chrono::Local::now());
-            ctx.text(message);
+            // Format the current time as HH:mm:ss
+            let current_time = Local::now().format("%H:%M:%S").to_string();
+            let message = ToFrontend::Landing(Landing { time: current_time });
+
+            // Serialize the message to JSON
+            if let Ok(json_message) = serde_json::to_string(&message) {
+                ctx.text(json_message);
+            } else {
+                info!("Failed to serialize the message");
+            }
         });
         info!("Leaving started");
     }
diff --git a/frontend/src/Page/Landing.elm b/frontend/src/Page/Landing.elm
index 1b2f048..4ad6c19 100644
--- a/frontend/src/Page/Landing.elm
+++ b/frontend/src/Page/Landing.elm
@@ -19,7 +19,7 @@ type alias Landing = {
     }
 type Msg
     = ToFrontend Landing
-    | Time String
+    | DecodeError Decode.Error
     | NoOp
 
 init : () -> Model
@@ -27,23 +27,15 @@ init flags = {
     time = "time not yet set"
     }
 
-decodeMessage : String -> String
-decodeMessage message =
+decodeToFrontend message =
     let
-        decodedMessage = Decode.decodeString (Decode.field "time" Decode.string) message
+        decodeTime = Decode.field "time" Decode.string |> Decode.map Landing
+        decodeLanding = Decode.field "Landing" decodeTime |> Decode.map ToFrontend
+        decodedMessage = Decode.decodeString decodeLanding message
     in
         case decodedMessage of
             Ok decoded -> decoded
-            Err err -> "failed to decode" ++ message
-
-decodeMessageOld : String -> String
-decodeMessageOld message =
-    let
-        decodedMessage = Decode.decodeString (Decode.field "time" Decode.string) message
-    in
-        case decodedMessage of
-            Ok decoded -> decoded
-            Err err -> "failed to decode" ++ message
+            Err err -> DecodeError err
 
 subscriptions : Model -> Sub Msg
 subscriptions model =
@@ -52,19 +44,19 @@ subscriptions model =
             (\_ -> NoOp)
             (\_ -> NoOp)
             (\_ -> NoOp)
-            (\message -> (message.data |> decodeMessageOld |> Time))
+            (\message -> (message.data |> decodeToFrontend))
             (\_ -> NoOp)
         )
 
 update : Msg -> Model -> (Model, Cmd Msg)
 update msg model =
     case msg of
-        Time time -> ( {model | time = time}, Cmd.none )
+        ToFrontend landing -> ( {model | time = landing.time}, Cmd.none )
         _ -> (model, Cmd.none)
 
 view : Model -> Element Msg
 view model =
     Element.column []
         [ Element.text "Landing",
-          Element.text <| "Time is : " ++ model.time
+          Element.text <| "Current time is : " ++ model.time
         ]