Dynamically sized article lookup

firmware/src/article.rs

@@ -1,4 +1,6 @@
+use alloc::collections::BTreeMap;
 use alloc::string::String;
+use alloc::vec::Vec;
 
 /// Article id
 /// Equivalent to the Vereinsflieger `articleid` attribute
@@ -18,52 +20,46 @@ pub struct Article {
 /// list of article ids is given on initialization (from static system configuration), while
 /// article information is fetched later from Vereinsflieger.
 #[derive(Debug)]
-pub struct Articles<const N: usize> {
-    ids: [ArticleId; N],
-    articles: [Option<Article>; N],
+pub struct Articles {
+    /// Look up index to article id
+    ids: Vec<ArticleId>,
+    /// Look up article id to article information
+    articles: BTreeMap<ArticleId, Article>,
 }
 
-impl<const N: usize> Articles<N> {
+impl Articles {
     /// Create new article lookup table
-    pub fn new(ids: [ArticleId; N]) -> Self {
+    pub fn new(ids: Vec<ArticleId>) -> Self {
         Self {
             ids,
-            articles: [const { None }; N],
+            articles: BTreeMap::new(),
         }
     }
 
     /// Clear all article information
     pub fn clear(&mut self) {
-        self.articles = [const { None }; N];
+        self.articles.clear();
     }
 
     /// Update article with given article id. Ignores article ids not in list.
     pub fn update(&mut self, id: &ArticleId, name: String, price: f32) {
-        if let Some(idx) = self.find(id) {
-            self.articles[idx] = Some(Article { name, price });
+        if self.ids.contains(id) {
+            self.articles.insert(id.clone(), Article { name, price });
         }
     }
 
     /// Number of articles
     pub fn count(&self) -> usize {
-        self.articles.iter().filter(|a| a.is_some()).count()
-    }
-
-    /// Find index of article with given id
-    pub fn find(&self, id: &ArticleId) -> Option<usize> {
-        self.ids.iter().position(|i| i == id)
+        self.articles.len()
     }
 
     /// Look up id of article at given index
     pub fn id(&self, index: usize) -> Option<&ArticleId> {
         self.ids.get(index)
     }
 
-    /// Look up article information at given index
-    pub fn get(&self, index: usize) -> Option<&Article> {
-        match self.articles.get(index) {
-            Some(Some(article)) => Some(article),
-            _ => None,
-        }
+    /// Look up article by article id
+    pub fn get(&self, id: &ArticleId) -> Option<&Article> {
+        self.articles.get(id)
     }
 }

firmware/src/main.rs

@@ -137,7 +137,7 @@ async fn main(spawner: Spawner) {
     let config = config::Config::read().await;
 
     // Initialize article and user look up tables
-    let mut articles = article::Articles::new([config.vf_article_ids[0].clone()]);
+    let mut articles = article::Articles::new(config.vf_article_ids);
     let mut users = user::Users::new();
 
     // Initialize I2C controller

firmware/src/ui.rs

@@ -48,7 +48,7 @@ pub struct Ui<'a, RNG, I2C, IRQ> {
     wifi: &'a Wifi,
     http: &'a mut Http<'a>,
     vereinsflieger: &'a mut Vereinsflieger<'a>,
-    articles: &'a mut Articles<1>,
+    articles: &'a mut Articles,
     users: &'a mut Users,
     telemetry: &'a mut Telemetry<'a>,
     schedule: &'a mut Daily,
@@ -66,7 +66,7 @@ impl<'a, RNG: RngCore, I2C: I2c, IRQ: Wait<Error = Infallible>> Ui<'a, RNG, I2C,
         wifi: &'a Wifi,
         http: &'a mut Http<'a>,
         vereinsflieger: &'a mut Vereinsflieger<'a>,
-        articles: &'a mut Articles<1>,
+        articles: &'a mut Articles,
         users: &'a mut Users,
         telemetry: &'a mut Telemetry<'a>,
         schedule: &'a mut Daily,
@@ -261,7 +261,10 @@ impl<'a, RNG: RngCore, I2C: I2c, IRQ: Wait<Error = Infallible>> Ui<'a, RNG, I2C,
                 .id(0)
                 .ok_or(ErrorKind::ArticleNotFound)?
                 .clone();
-            let article = self.articles.get(0).ok_or(ErrorKind::ArticleNotFound)?;
+            let article = self
+                .articles
+                .get(&article_id)
+                .ok_or(ErrorKind::ArticleNotFound)?;
 
             // Calculate total price. It's ok to cast num_drinks to f32 as it's always a small number.
             #[allow(clippy::cast_precision_loss)]

firmware/src/user.rs

@@ -29,7 +29,7 @@ pub struct User {
 pub struct Users {
     /// Look up NFC uid to user id
     uids: BTreeMap<Uid, UserId>,
-    /// Look up user id to user details
+    /// Look up user id to user information
     users: BTreeMap<UserId, User>,
 }
 

firmware/src/vereinsflieger/mod.rs

@@ -148,10 +148,7 @@ impl Connection<'_> {
     }
 
     /// Fetch list of articles and update article lookup table
-    pub async fn refresh_articles<const N: usize>(
-        &mut self,
-        articles: &mut Articles<N>,
-    ) -> Result<(), Error> {
+    pub async fn refresh_articles(&mut self, articles: &mut Articles) -> Result<(), Error> {
         use proto_articles::{ArticleListRequest, ArticleListResponse};
 
         debug!("Vereinsflieger: Refreshing articles...");
@@ -172,7 +169,7 @@ impl Connection<'_> {
         articles.clear();
         let articles = RefCell::new(articles);
 
-        let response: ArticleListResponse<N> =
+        let response: ArticleListResponse =
             with_timeout(FETCH_TIMEOUT, json.read_object_with_context(&articles))
                 .await?
                 .map_err(http::Error::MalformedResponse)

firmware/src/vereinsflieger/proto_articles.rs

@@ -30,17 +30,17 @@ impl ToJson for ArticleListRequest<'_> {
 
 /// `articles/list` response
 #[derive(Debug, Default)]
-pub struct ArticleListResponse<const N: usize> {
+pub struct ArticleListResponse {
     // pub *: Article,
     // pub httpstatuscode: u16,
     //
     /// Total number of articles
     pub total_articles: u32,
 }
 
-impl<const N: usize> FromJsonObject for ArticleListResponse<N> {
+impl FromJsonObject for ArticleListResponse {
     // Mutable reference to article lookup table
-    type Context<'ctx> = RefCell<&'ctx mut Articles<N>>;
+    type Context<'ctx> = RefCell<&'ctx mut Articles>;
 
     async fn read_next<R: BufRead>(
         &mut self,