Add help and ping command

Cargo.lock

@@ -498,6 +498,26 @@ dependencies = [
  "cfg-if 0.1.10",
 ]
 
+[[package]]
+name = "enum-iterator"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4eeac5c5edb79e4e39fe8439ef35207780a11f69c52cbe424ce3dfad4cb78de6"
+dependencies = [
+ "enum-iterator-derive",
+]
+
+[[package]]
+name = "enum-iterator-derive"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c134c37760b27a871ba422106eedbb8247da973a09e82558bf26d619c882b159"
+dependencies = [
+ "proc-macro2 1.0.36",
+ "quote 1.0.18",
+ "syn 1.0.92",
+]
+
 [[package]]
 name = "event-listener"
 version = "2.5.2"
@@ -1059,6 +1079,7 @@ name = "matrix-bot"
 version = "0.1.0"
 dependencies = [
  "clap 3.1.16",
+ "enum-iterator",
  "matrix-sdk",
  "serde",
  "tokio",

Cargo.toml

@@ -16,6 +16,7 @@ toml = "0.5"
 clap = { version = "3", features = ["derive"] }
 serde = { version = "1", features = ["derive"] }
 uwuify = "0.2"
+enum-iterator = "0.7"
 
 [profile.release]
 strip = true

src/main.rs

@@ -1,9 +1,12 @@
 #![warn(clippy::nursery, clippy::pedantic)]
 
+use std::fmt::Display;
 use std::path::PathBuf;
+use std::str::FromStr;
 use std::time::Duration;
 
 use clap::Parser;
+use enum_iterator::IntoEnumIterator;
 use matrix_sdk::room::{Joined, Room};
 use matrix_sdk::ruma::events::room::member::MemberEventContent;
 use matrix_sdk::ruma::events::room::message::{
@@ -163,9 +166,11 @@ async fn parse_message(event: SyncMessageEvent<MessageEventContent>, room: Joine
 
     if let Some(message) = message.strip_prefix('!') {
         let (command, args) = message.split_once(' ').unwrap_or((message, ""));
-        match command {
-            "source" => source(room).await?,
-            "uwu" => uwuify(room, args).await?,
+        match BotCommand::from_str(command).ok() {
+            Some(BotCommand::Source) => source(room).await?,
+            Some(BotCommand::Uwu) => uwuify(room, args).await?,
+            Some(BotCommand::Ping) => ping(room).await?,
+            Some(BotCommand::Help) => help(room).await?,
             _ => unsupported_command(event, room, command).await?,
         }
     }
@@ -173,6 +178,50 @@ async fn parse_message(event: SyncMessageEvent<MessageEventContent>, room: Joine
     Ok(())
 }
 
+#[derive(enum_iterator::IntoEnumIterator)]
+enum BotCommand {
+    Help,
+    Source,
+    Uwu,
+    Ping,
+}
+
+impl BotCommand {
+    const fn help_text(&self) -> &'static str {
+        match self {
+            Self::Source => "Links to the source code for this bot.",
+            Self::Uwu => "Uwuifies your message.",
+            Self::Ping => "Pong!",
+            Self::Help => "Prints this help.",
+        }
+    }
+}
+
+impl FromStr for BotCommand {
+    type Err = ();
+
+    fn from_str(s: &str) -> std::result::Result<Self, Self::Err> {
+        match s.to_lowercase().as_str() {
+            "source" => Ok(Self::Source),
+            "uwu" => Ok(Self::Uwu),
+            "ping" => Ok(Self::Ping),
+            "help" => Ok(Self::Help),
+            _ => Err(()),
+        }
+    }
+}
+
+impl Display for BotCommand {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            BotCommand::Source => write!(f, "source"),
+            BotCommand::Uwu => write!(f, "uwu"),
+            BotCommand::Ping => write!(f, "ping"),
+            BotCommand::Help => write!(f, "help"),
+        }
+    }
+}
+
 async fn source(room: Joined) -> Result<()> {
     let content = MessageEventContent::text_plain("https://git.eddie.sh/edward/matrix-bot");
     room.send(content, None).await?;
@@ -185,6 +234,25 @@ async fn uwuify(room: Joined, message: &str) -> Result<()> {
     Ok(())
 }
 
+async fn ping(room: Joined) -> Result<()> {
+    let content = MessageEventContent::text_plain("Pong!");
+    room.send(content, None).await?;
+    Ok(())
+}
+
+async fn help(room: Joined) -> Result<()> {
+    let mut msg = "List of commands:\n\n".to_owned();
+    for command in BotCommand::into_enum_iter() {
+        msg.push_str(&command.to_string());
+        msg.push_str(" - ");
+        msg.push_str(command.help_text());
+        msg.push_str("\n");
+    }
+    let content = MessageEventContent::notice_plain(msg);
+    room.send(content, None).await?;
+    Ok(())
+}
+
 async fn unsupported_command(
     original_event: SyncMessageEvent<MessageEventContent>,
     room: Joined,