refactor/feat: add xkcd.ru, for-loop -> iter

src/main.rs

@@ -7,6 +7,8 @@ use tokio::signal::unix::{signal, SignalKind};
 const BOT_URL: &str = "https://api.telegram.org/bot";
 /// Command to search for in a message text
 const COMMAND: &str = "/xkcd";
+/// Length of the command substring
+const CMD_LEN: usize = COMMAND.len();
 /// Long polling timeout in seconds
 const POLL_TIMEOUT: &str = "300";
 /// Update types to receive (filtered out on tg backend)
@@ -58,11 +60,13 @@ struct TgChat {
     // is_forum: bool,
 }
 
-/// XKCD.com API comic info schema
+/// XKCD API comic info schema
 #[derive(Debug, Deserialize)]
 struct XkcdInfo {
-    alt: String,
-    img: String,
+    #[serde(alias = "text")] // xkcd.ru
+    alt: String, // xkcd.com
+    #[serde(alias = "image")] // xkcd.ru
+    img: String, // xkcd.com
 }
 
 #[tokio::main]
@@ -122,30 +126,43 @@ async fn handler(cfg: &Config, s: &mut State) -> Result<(), reqwest::Error> {
         .await?
         .result;
 
-    for u in &mut updates {
-        let Some(mut msg) = u.message.take() else {
-            continue;
-        };
-
-        let Some(text) = msg.text.take() else {
-            continue;
-        };
-
-        if !text.starts_with(COMMAND) {
-            continue;
-        }
-
-        let Some(comic_id) = text
-            .split_whitespace()
-            .skip(1)
-            .next()
-            .and_then(|id| id.parse::<u16>().ok())
-        else {
-            continue;
-        };
-
-        tokio::spawn(send_comic(cfg.clone(), msg, comic_id));
-    }
+    updates
+        .iter_mut()
+        .filter_map(|u| {
+            u.message.take().and_then(|mut msg| {
+                msg.text.take().and_then(|text| {
+                    // starts with our command
+                    if text.get(..CMD_LEN)? == COMMAND
+                        // check space or @ after cmd name
+                        // to ensure that our command is
+                        // not a part of any other cmd
+                        && [" ", "@"].contains(&text.get(CMD_LEN..CMD_LEN + 1)?)
+                    {
+                        let mut args = text.split_whitespace();
+                        args.next(); // skip command name
+                        match args.next()? {
+                            "ru" => {
+                                let comic_id = args.next()?.parse::<u16>().ok()?;
+                                Some((msg, format!("https://xkcd.ru/{}/?json=true", comic_id)))
+                            }
+                            "en" => {
+                                let comic_id = args.next()?.parse::<u16>().ok()?;
+                                Some((msg, format!("https://xkcd.com/{}/info.0.json", comic_id)))
+                            }
+                            comic_id => {
+                                let comic_id = comic_id.parse::<u16>().ok()?;
+                                Some((msg, format!("https://xkcd.com/{}/info.0.json", comic_id)))
+                            }
+                        }
+                    } else {
+                        None
+                    }
+                })
+            })
+        })
+        .for_each(|(msg, url)| {
+            tokio::spawn(send_comic(cfg.clone(), msg, url));
+        });
 
     if let Some(u) = updates.last() {
         s.offset = u.update_id + 1;
@@ -154,14 +171,8 @@ async fn handler(cfg: &Config, s: &mut State) -> Result<(), reqwest::Error> {
     Ok(())
 }
 
-async fn send_comic(cfg: Config, msg: TgMessage, comic_id: u16) -> Result<(), reqwest::Error> {
-    let info = cfg
-        .client
-        .get(format!("https://xkcd.com/{}/info.0.json", comic_id))
-        .send()
-        .await?
-        .json::<XkcdInfo>()
-        .await?;
+async fn send_comic(cfg: Config, msg: TgMessage, url: String) -> Result<(), reqwest::Error> {
+    let info = cfg.client.get(url).send().await?.json::<XkcdInfo>().await?;
 
     cfg.client
         .post((*cfg.send_url).clone())