feat(tools): cli to help generate files for new problems, and problem 1 rewritten in rust

.gitignore

@@ -1 +1,2 @@
 /target
+/ignore

Cargo.toml

@@ -1,8 +1,17 @@
 [package]
 name = "euler"
-version = "0.1.0"
+version = "1.0.0"
 edition = "2021"
+default-run = "euler"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+clap = { version = "4.0.4", features = ["derive"] }
+owo-colors = "3.5.0"
+scraper = "0.14.0"
+requestty = "0.4.1"
+reqwest = "0.11"
+tokio = { version = "1.23", features = ["full"] }
+regex = "1"
+html-escape = "0.2.13"

readme.md

@@ -0,0 +1 @@
+# readme coming soon

src/bin/1.rs

@@ -0,0 +1,29 @@
+// Problem 1 - Multiples of 3 or 5
+
+// If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23. 
+// Find the sum of all the multiples of 3 or 5 below 1000. 
+
+use std::collections::HashSet;
+
+fn multiples_of(multipliers: &Vec<usize>, upper_bound: usize) -> HashSet<usize> {
+	let mut results: HashSet<usize> = HashSet::new();
+
+	// Find all of the numbers between 1 and the upper bound that are multiples of one of the numbers
+	// in the multipliers vec
+	for i in 1..upper_bound {
+		for number in multipliers {			
+			if i % number == 0 {
+				results.insert(i);
+			}
+		}
+	}
+
+	return results;
+}
+
+fn main() {
+	let multiples = multiples_of(&vec![3, 5], 1000);
+	let sum: usize = multiples.iter().sum();
+
+	println!("The sum of the multiples of 3 and 5 up until 1000 is {sum}");
+}

src/main.rs

@@ -1,3 +1,123 @@
-fn main() {
-    println!("Hello, world!");
+use clap::{Parser, Subcommand};
+use owo_colors::OwoColorize;
+use std::{fs, path::Path, io::Write};
+use scraper::{Html, Selector};
+use regex::Regex;
+
+#[derive(Parser)]
+#[clap(about, author, version)]
+struct Value {
+    #[clap(subcommand)]
+    command: Commands
+}
+
+#[derive(Subcommand)]
+enum Commands {
+    /// Handles the initialisation of a new Project Euler Problem
+    New,
+}
+
+#[tokio::main]
+async fn new() -> Result<(), Box<dyn std::error::Error>> {
+    let code_path = Path::new(env!("CARGO_MANIFEST_DIR")).join("src").join("bin");
+
+    let problem_number = requestty::prompt_one(
+        requestty::Question::int("problemNumber")
+            .message("Which problem would you like to solve?")
+            .validate(|n, _| {
+                // All numbers must be positive
+                let mut pass = n > 0;
+
+                // Ensure that the problem has not already got a file associated with it
+                let files = fs::read_dir(&code_path).unwrap();
+
+                for file in files {
+                    let file_number = file
+                        .unwrap()
+                        .file_name()
+                        .to_str()
+                        .unwrap()
+                        .split('.')
+                        .collect::<Vec<&str>>()[0]
+                        .parse::<i64>()
+                        .unwrap();
+
+                    if n == file_number && pass {
+                        pass = false;
+                    }
+                }
+
+                if pass {
+                    Ok(())
+                } else {
+                    Err("Please ensure that your input is valid!".to_owned())
+                }
+            })
+            .build()
+    ).unwrap().as_int().unwrap();
+
+    // todo: thoughts documents (?)
+    
+    // Fetch the problem information
+    let body = reqwest::get(format!("https://projecteuler.net/problem={problem_number}")).await?.text().await?;
+
+    let document = Html::parse_document(Box::leak(body.into_boxed_str()));
+    let title_selector = Selector::parse("h2")?;
+    let content_selector = Selector::parse(".problem_content")?;
+    let re = Regex::new(r"<[^>]*>").unwrap();
+
+    let mut title = document
+        .select(&title_selector)
+        .next()
+        .unwrap()
+        .text()
+        .collect::<Vec<&str>>()
+        .join("");
+
+    let mut problem = re.replace_all(
+        Box::leak(
+            document
+                .select(&content_selector)
+                .next()
+                .unwrap()
+                .inner_html()
+                .into_boxed_str()
+        ), 
+        " "
+    ).to_string();
+
+    let file_body = format!(
+        "// Problem {} - {}
+
+//{}
+
+fn main() {{
+    println!(\"Hello World!\");  
+}}", 
+        problem_number,
+        html_escape::decode_html_entities(&mut title).to_string(),
+        html_escape::decode_html_entities(&mut problem).split("\n").filter(|s| s != &"").collect::<Vec<&str>>().join("\n//")
+    );
+
+    // Create the file
+    let mut file = fs::File::create(code_path.join(format!("{problem_number}.rs"))).unwrap();
+    file.write(file_body.as_bytes()).unwrap();
+    drop(file);
+
+    // todo: update readme
+
+    // Announce completion!
+    println!("{}", "File successfully created! Good luck (:".green());
+
+    Ok(())
+}
+
+// todo: runner
+
+fn main() {
+    let value = Value::parse();
+
+    match value.command {
+        Commands::New => new().unwrap(),
+    }
 }