feat: add get_feed_config function in templates

src/template_engine.rs

@@ -4,9 +4,10 @@ use crate::Config;
 use anyhow::Result;
 use camino::Utf8Path;
 use feed_rs::model::Feed;
-use std::collections::HashMap;
+use std::collections::{BTreeMap, HashMap};
 use std::fs::{copy, create_dir_all, File};
 use tera::{from_value, Tera};
+use url::Url;
 
 pub fn build(config: &Config, feed_store: &mut FeedStore) -> Result<()> {
     let mut tera = if let Some(theme) = &config.theme {
@@ -27,6 +28,9 @@ pub fn build(config: &Config, feed_store: &mut FeedStore) -> Result<()> {
     context.insert("PKG_NAME", env!("CARGO_PKG_NAME"));
     context.insert("PKG_VERSION", env!("CARGO_PKG_VERSION"));
     tera.register_function("get_author", GetAuthorFunction { feeds });
+    tera.register_function("get_feed_config", GetFeedConfigFunction {
+        feeds: config.feeds.iter().map(|feed| (feed.url.clone(), feed.clone())).collect()
+    });
 
     for name in tera.get_template_names() {
         debug!("Processing template {name}");
@@ -73,6 +77,31 @@ fn create_tera(templates_dir: &Utf8Path) -> Result<Tera> {
     Ok(tera)
 }
 
+struct GetFeedConfigFunction {
+    feeds: BTreeMap<Url, super::FeedConfig>,
+}
+
+impl tera::Function for GetFeedConfigFunction {
+    fn call(&self, args: &HashMap<String, tera::Value>) -> Result<tera::Value, tera::Error> {
+        let feed: Url = match args.get("feed") {
+            None => {
+                return Err(tera::Error::msg(
+                    "No argument of name 'feed' given to function.",
+                ))
+            }
+            Some(val) => from_value(val.clone())?,
+        };
+
+        if let Some(feed_config) = self.feeds.get(&feed) {
+            Ok(tera::to_value(feed_config)?)
+        } else {
+            Err(tera::Error::msg(
+                format!("Invalid feed URL: {}", feed),
+            ))
+        }
+    }
+}
+
 struct GetAuthorFunction {
     feeds: HashMap<String, Feed>,
 }