Add /reminder command

Cargo.lock

@@ -772,6 +772,12 @@ dependencies = [
  "unicase",
 ]
 
+[[package]]
+name = "minimal-lexical"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "68354c5c6bd36d73ff3feceb05efa59b6acb7626617f4962be322a825e61f79a"
+
 [[package]]
 name = "miniz_oxide"
 version = "0.7.4"
@@ -815,6 +821,16 @@ version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c96aba5aa877601bb3f6dd6a63a969e1f82e60646e81e71b14496995e9853c91"
 
+[[package]]
+name = "nom"
+version = "7.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d273983c5a657a70a3e8f2a01329822f3b8c8172b73826411a55751e404a0a4a"
+dependencies = [
+ "memchr",
+ "minimal-lexical",
+]
+
 [[package]]
 name = "num-traits"
 version = "0.2.19"
@@ -893,6 +909,17 @@ dependencies = [
  "vcpkg",
 ]
 
+[[package]]
+name = "parse_datetime"
+version = "0.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a8720474e3dd4af20cea8716703498b9f3b690f318fa9d9d9e2e38eaf44b96d0"
+dependencies = [
+ "chrono",
+ "nom",
+ "regex",
+]
+
 [[package]]
 name = "percent-encoding"
 version = "2.3.1"
@@ -1124,8 +1151,11 @@ dependencies = [
  "diesel",
  "log",
  "micronfig",
+ "once_cell",
+ "parse_datetime",
  "pretty_env_logger",
  "rand",
+ "regex",
  "teloxide",
  "tokio",
 ]

Cargo.toml

@@ -12,4 +12,7 @@ micronfig = "0.3.0"
 pretty_env_logger = "0.5.0"
 rand = { version = "0.8.5", features = ["small_rng"] }
 teloxide = { version = "0.12.2", features = ["ctrlc_handler", "native-tls", "macros"], default-features = false }
-tokio = { version = "1.38.0", features = ["macros", "rt-multi-thread"] }
+tokio = { version = "1.38.0", features = ["macros", "rt-multi-thread", "time"] }
+parse_datetime = "0.6.0"
+regex = "1.10.5"
+once_cell = "1.19.0"

src/main.rs

@@ -2,6 +2,7 @@ use anyhow::Result;
 use crate::telegram::DispatchWithResult;
 
 pub(crate) mod database;
+pub(crate) mod utils;
 mod telegram;
 
 #[tokio::main]

src/telegram/commands/mod.rs

@@ -16,6 +16,7 @@ mod echo;
 mod help;
 mod whoami;
 mod answer;
+mod reminder;
 
 #[derive(Debug, Clone, PartialEq, Eq, BotCommands)]
 #[command(rename_rule = "lowercase")]
@@ -32,6 +33,8 @@ enum Command {
 	WhoAmI,
 	#[command(description = "Rispondi ad una domanda.")]
 	Answer(String),
+	#[command(description = "Ricorda la chat di qualcosa che avverrà in futuro.")]
+	Reminder(reminder::ReminderArgs),
 }
 
 async fn handle_command(bot: Bot, command: Command, message: Message) -> CommandResult {
@@ -47,6 +50,7 @@ async fn handle_command(bot: Bot, command: Command, message: Message) -> Command
 		Command::Echo(text) => echo::handler(&bot, &message, &text).await,
 		Command::WhoAmI => whoami::handler(&bot, &message).await,
 		Command::Answer(_) => answer::handler(&bot, &message).await,
+		Command::Reminder(args) => reminder::handler(&bot, &message, args).await,
 	};
 
 	if result.is_ok() {

src/telegram/commands/reminder.rs

@@ -0,0 +1,88 @@
+use std::str::FromStr;
+use anyhow::Context;
+use teloxide::Bot;
+use teloxide::payloads::SendMessageSetters;
+use teloxide::requests::Requester;
+use teloxide::types::{Message};
+use parse_datetime::parse_datetime_at_date;
+use once_cell::sync::Lazy;
+use regex::Regex;
+use super::{CommandResult};
+
+
+fn determine_wait(target_chrono: chrono::DateTime<chrono::Local>) -> tokio::time::Duration {
+	let now_chrono = chrono::Local::now();
+
+	let duration_chrono = target_chrono.signed_duration_since(now_chrono);
+	let seconds = duration_chrono.num_seconds();
+
+	tokio::time::Duration::from_secs(seconds as u64)
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct ReminderArgs {
+	target: chrono::DateTime<chrono::Local>,
+	reminder: String,
+}
+
+impl FromStr for ReminderArgs {
+	type Err = anyhow::Error;
+
+	fn from_str(s: &str) -> Result<Self, Self::Err> {
+		static REGEX: Lazy<Regex> = Lazy::new(|| Regex::new(r"\[(?<target>.*)]\s*(?<reminder>.+)$").unwrap());
+
+		let captures = REGEX.captures(s)
+			.context("Sintassi del comando incorretta.")?;
+
+		let target = captures.name("target")
+			.unwrap()
+			.as_str();
+
+		let reminder = captures.name("reminder")
+			.unwrap()
+			.as_str()
+			.to_string();
+
+		let target = parse_datetime_at_date(chrono::Local::now(), target)
+			.context("Impossibile determinare la data in cui l'attesa avrà termine.")?
+			.with_timezone(&chrono::Local);
+
+		Ok(
+			ReminderArgs { target, reminder }
+		)
+	}
+}
+
+pub async fn handler(bot: &Bot, message: &Message, ReminderArgs { target, reminder}: ReminderArgs) -> CommandResult {
+	let text = format!(
+		"🕒 Promemoria per {} impostato\n\
+		{}",
+		target.format("%c"),
+		reminder
+	);
+
+	let _reply = bot
+		.send_message(message.chat.id, text)
+		.reply_to_message_id(message.id)
+		.await
+		.context("Non è stato possibile inviare la conferma.")?;
+
+	let wait_duration = determine_wait(target);
+
+	tokio::time::sleep(wait_duration).await;
+
+	let text = format!(
+		"🕒 Promemoria per {} attivato\n\
+		{}",
+		target.format("%c"),
+		reminder
+	);
+
+	let _reply = bot
+		.send_message(message.chat.id, text)
+		.reply_to_message_id(message.id)
+		.await
+		.context("Non è stato possibile inviare il promemoria.")?;
+
+	Ok(())
+}

src/utils/mod.rs

@@ -0,0 +1 @@
+pub mod time;