Add dicebot-roll dice expression parser

Cargo.lock

@@ -1,5 +1,14 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
+[[package]]
+name = "aho-corasick"
+version = "0.7.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8716408b8bc624ed7f65d223ddb9ac2d044c0547b6fa4b0d554f3a9540496ada"
+dependencies = [
+ "memchr",
+]
+
 [[package]]
 name = "arc-swap"
 version = "0.4.5"
@@ -16,6 +25,7 @@ checksum = "f8aac770f1885fd7e387acedd76065302551364496e46b3dd00860b2f8359b9d"
 name = "axfive-matrix-dicebot"
 version = "0.1.0"
 dependencies = [
+ "regex",
  "reqwest",
  "serde",
  "serde_json",
@@ -581,6 +591,24 @@ version = "0.1.56"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2439c63f3f6139d1b57529d16bc3b8bb855230c8efcc5d3a896c8bea7c3b1e84"
 
+[[package]]
+name = "regex"
+version = "1.3.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a6020f034922e3194c711b82a627453881bc4682166cabb07134a10c26ba7692"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-syntax",
+ "thread_local",
+]
+
+[[package]]
+name = "regex-syntax"
+version = "0.6.17"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7fe5bd57d1d7414c6b5ed48563a2c855d995ff777729dcd91c369ec7fea395ae"
+
 [[package]]
 name = "remove_dir_all"
 version = "0.5.2"
@@ -754,6 +782,15 @@ dependencies = [
  "winapi 0.3.8",
 ]
 
+[[package]]
+name = "thread_local"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d40c6d1b69745a6ec6fb1ca717914848da4b44ae29d9b3080cbee91d72a69b14"
+dependencies = [
+ "lazy_static",
+]
+
 [[package]]
 name = "time"
 version = "0.1.42"

Cargo.toml

@@ -9,7 +9,8 @@ edition = "2018"
 [dependencies]
 reqwest = "^0.10"
 serde_json = "^1"
-toml = "0.5"
+toml = "^0.5"
+regex = "^1.3"
 
 [dependencies.serde]
 version = "^1"

axfive-matrix-dicebot.code-workspace

@@ -0,0 +1,7 @@
+{
+	"folders": [
+		{
+			"path": "."
+		}
+	]
+}

src/bin/dicebot-roll.rs

@@ -0,0 +1,128 @@
+use regex::Regex;
+use std::error::Error;
+use std::fmt;
+use std::str::FromStr;
+
+#[derive(Debug)]
+struct ParseError {
+    reason: String,
+}
+
+impl fmt::Display for ParseError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "ParseError: {}", self.reason)
+    }
+}
+
+impl Error for ParseError {}
+
+#[derive(Debug)]
+struct Dice {
+    count: u32,
+    sides: u32,
+}
+
+#[derive(Debug)]
+enum Roll {
+    Dice(Dice),
+    Bonus(u32),
+}
+
+impl From<u32> for Roll {
+    fn from(value: u32) -> Roll {
+        Roll::Bonus(value)
+    }
+}
+
+impl From<Dice> for Roll {
+    fn from(value: Dice) -> Roll {
+        Roll::Dice(value)
+    }
+}
+
+impl FromStr for Roll {
+    type Err = Box<dyn Error>;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        let s = s.trim();
+        let regex = Regex::new(r"(?i)^(\d+)\s*(d\s*(\d+))?$")?;
+        let captures = match regex.captures(s) {
+            Some(captures) => captures,
+            None => {
+                return Err(ParseError {
+                    reason: format!("{:?} is not a legal Roll Part expression", s),
+                }
+                .into())
+            }
+        };
+
+        match captures.get(2) {
+            Some(_) => Ok(Dice {
+                count: captures.get(1).unwrap().as_str().parse()?,
+                sides: captures.get(3).unwrap().as_str().parse()?,
+            }
+            .into()),
+            None => Ok(Roll::Bonus(captures.get(1).unwrap().as_str().parse()?)),
+        }
+    }
+}
+
+#[derive(Debug)]
+enum Part {
+    Plus(Roll),
+    Minus(Roll),
+}
+
+impl FromStr for Part {
+    type Err = Box<dyn Error>;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        let s = s.trim();
+
+        match s.chars().next() {
+            Some('+') => Ok(Part::Plus(s[1..].parse()?)),
+            Some('-') => Ok(Part::Minus(s[1..].parse()?)),
+            Some(_) => Ok(Part::Plus(s.parse()?)),
+            None => Err(ParseError {
+                reason: format!("{:?} is not a legal Roll Part expression", s),
+            }
+            .into()),
+        }
+    }
+}
+
+#[derive(Debug)]
+struct Expression(Vec<Part>);
+
+impl FromStr for Expression {
+    type Err = Box<dyn Error>;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        let s = s.trim();
+        let validation_regex = Regex::new(
+            r"(?xi)^
+        ([-\+])?\s*(\d+)\s*(d\s*(\d+))?
+        (\s*([-\+])\s*(\d+)\s*(d\s*(\d+))?)*
+        $",
+        )?;
+        if !validation_regex.is_match(s) {
+            return Err(ParseError {
+                reason: format!("{:?} is not a legal dice expression", s),
+            }
+            .into());
+        }
+
+        let part = Regex::new(r"(?i)[-\+]?\s*\d+\s*(d\s*(\d+))?")?;
+
+        let results: Result<_, _> = part.find_iter(s).map(|p| p.as_str().parse()).collect();
+        Ok(Expression(results?))
+    }
+}
+
+fn main() -> Result<(), Box<dyn Error>> {
+    let roll_string = std::env::args().skip(1).collect::<Vec<String>>().join(" ");
+    // first regex needs to be different because the sign is mandatory for the rest
+    let expression: Expression = roll_string.parse()?;
+    println!("{:?}", expression);
+    Ok(())
+}

src/bin/dicebot.rs

@@ -1,6 +1,6 @@
+use axfive_matrix_dicebot::bot::DiceBot;
 use tokio::select;
 use tokio::signal::unix::{signal, SignalKind};
-use axfive_matrix_dicebot::bot::DiceBot;
 
 #[tokio::main]
 async fn main() -> Result<(), Box<dyn std::error::Error>> {

src/bot.rs

@@ -1,10 +1,11 @@
-use serde::{self, Deserialize, Serialize};
-use reqwest::{Client, Url};
 use crate::matrix::SyncCommand;
-use std::path::PathBuf;
+use reqwest::{Client, Url};
+use serde::{self, Deserialize, Serialize};
 use std::fs;
+use std::path::PathBuf;
 
-const USER_AGENT: &str = "AxFive Matrix DiceBot/0.1.0 (+https://gitlab.com/Taywee/axfive-matrix-dicebot)";
+const USER_AGENT: &str =
+    "AxFive Matrix DiceBot/0.1.0 (+https://gitlab.com/Taywee/axfive-matrix-dicebot)";
 
 /// The "matrix" section of the config, which gives home server, login information, and etc.
 #[derive(Serialize, Deserialize, Debug)]
@@ -42,13 +43,17 @@ struct LoginResponse {
 
 impl DiceBot {
     /// Create a new dicebot from the given config path and config
-    pub async fn new(config_path: Option<PathBuf>, config: Config) -> Result<Self, Box<dyn std::error::Error>> {
+    pub async fn new(
+        config_path: Option<PathBuf>,
+        config: Config,
+    ) -> Result<Self, Box<dyn std::error::Error>> {
         let home_server: Url = format!("https://{}", config.matrix.home_server).parse()?;
         let client = Client::new();
         let request = serde_json::to_string(&config.matrix.login)?;
         let mut login_url = home_server.clone();
         login_url.set_path("/_matrix/client/r0/login");
-        let response = client.post(login_url)
+        let response = client
+            .post(login_url)
             .header("user-agent", USER_AGENT)
             .body(request)
             .send()
@@ -66,7 +71,9 @@ impl DiceBot {
     }
 
     /// Create a new dicebot, storing the config path to write it out  
-    pub async fn from_path<P: Into<PathBuf>>(config_path: P) -> Result<Self, Box<dyn std::error::Error>> {
+    pub async fn from_path<P: Into<PathBuf>>(
+        config_path: P,
+    ) -> Result<Self, Box<dyn std::error::Error>> {
         let config_path = config_path.into();
         let config = {
             let contents = fs::read_to_string(&config_path)?;
@@ -98,10 +105,11 @@ impl DiceBot {
 
         // TODO: handle http 429
         if let Some(since) = &self.next_batch {
-            sync_url.query_pairs_mut()
-                .append_pair("since", since);
+            sync_url.query_pairs_mut().append_pair("since", since);
         }
-        let body = self.client.get(sync_url)
+        let body = self
+            .client
+            .get(sync_url)
             .header("user-agent", USER_AGENT)
             .send()
             .await?
@@ -117,7 +125,8 @@ impl DiceBot {
     /// construction
     pub async fn logout(mut self) -> Result<(), Box<dyn std::error::Error>> {
         let logout_url = self.url("/_matrix/client/r0/logout", &[]);
-        self.client.post(logout_url)
+        self.client
+            .post(logout_url)
             .header("user-agent", USER_AGENT)
             .body("{}")
             .send()

src/lib.rs

@@ -1,2 +1,2 @@
-pub mod matrix;
 pub mod bot;
+pub mod matrix;

src/matrix.rs

@@ -5,7 +5,7 @@ use std::collections::HashMap;
 #[serde(tag = "msgtype")]
 #[serde(rename = "m.text")]
 pub struct TextMessage {
-    body: String
+    body: String,
 }
 
 // Need untagged because redactions are blank