From 829dad2c5f8526dfb11f2e4c7e7afd47e46e8998 Mon Sep 17 00:00:00 2001
From: Nathan Fisher <jeang3nie@hitchhiker-linux.org>
Date: Tue, 3 Jan 2023 12:49:09 -0500
Subject: [PATCH] Added factor applet

---
 src/cmd/base32/mod.rs  |  2 +-
 src/cmd/factor/mod.rs  | 86 ++++++++++++++++++++++++++++++++++++++++++
 src/cmd/mod.rs         |  2 +
 src/cmd/shitbox/mod.rs |  4 +-
 src/lib.rs             |  4 +-
 5 files changed, 94 insertions(+), 4 deletions(-)
 create mode 100644 src/cmd/factor/mod.rs

diff --git a/src/cmd/base32/mod.rs b/src/cmd/base32/mod.rs
index 33605a6..70b8625 100644
--- a/src/cmd/base32/mod.rs
+++ b/src/cmd/base32/mod.rs
@@ -25,7 +25,7 @@ impl Cmd for Base32 {
 
     fn cli(&self) -> clap::Command {
         Command::new("base32")
-            .author("The JeanG3nie <jeang3nie@hitchhiker-linux.org>")
+            .author("Nathan Fisher")
             .about("Base32 encode/decode data and print to standard output")
             .args([
                 Arg::new("INPUT")
diff --git a/src/cmd/factor/mod.rs b/src/cmd/factor/mod.rs
new file mode 100644
index 0000000..8c258af
--- /dev/null
+++ b/src/cmd/factor/mod.rs
@@ -0,0 +1,86 @@
+use clap::{Arg, ArgMatches, Command, value_parser};
+use crate::Cmd;
+use std::{error::Error, io::{self, BufRead}};
+
+#[derive(Debug)]
+pub struct Factor {
+    name: &'static str,
+    path: Option<crate::Path>,
+}
+
+pub const FACTOR: Factor = Factor {
+    name: "factor",
+    path: Some(crate::Path::UsrBin),
+};
+
+impl Cmd for Factor {
+    fn name(&self) -> &str {
+        self.name
+    }
+
+    fn cli(&self) -> Command {
+        Command::new("factor")
+            .about("factor numbers")
+            .after_help(
+                "Print the prime factors of each specified integer NUMBER.  If none are\n\
+                specified on the command line, read them from standard input."
+            )
+            .arg(
+                Arg::new("number")
+                    .help("the numbers to factor")
+                    .num_args(0..)
+                    .value_parser(value_parser!(u64))
+            )
+    }
+
+    fn run(&self, matches: Option<&ArgMatches>) -> Result<(), Box<dyn Error>> {
+        if let Some(matches) = matches {
+            match matches.get_many::<u64>("number") {
+                Some(numbers) => {
+                    numbers.for_each(|n| print_factors(*n));
+                },
+                None => {
+                    for line in io::stdin().lock().lines() {
+                        for value in line.unwrap().split_whitespace() {
+                            let num: u64 = value.parse()?;
+                            print_factors(num);
+                        }
+                    }
+                },
+            }
+        }
+        Ok(())
+    }
+
+    fn path(&self) -> Option<crate::Path> {
+        self.path
+    }
+}
+
+fn is_prime(num: u64) -> bool {
+    match num {
+        0 | 1 => false,
+        2 | 3 | 5 | 7 | 11 | 13 => true,
+        x if x % 2 == 0 => false,
+        _ => {
+            let mut x: u64 = 2;
+            while x < num / 2 {
+                if num % x == 0 {
+                    return false;
+                }
+                x += 1;
+            }
+            true
+        }
+    }
+}
+
+fn print_factors(num: u64) {
+    print!("{num}:");
+    for n in 2..=num / 2 {
+        if num % n == 0 && is_prime(n) {
+            print!(" {n}");
+        }
+    }
+    println!();
+}
diff --git a/src/cmd/mod.rs b/src/cmd/mod.rs
index 4d9c130..13e3c9f 100644
--- a/src/cmd/mod.rs
+++ b/src/cmd/mod.rs
@@ -18,6 +18,7 @@ mod date;
 mod dd;
 pub mod dirname;
 pub mod echo;
+pub mod factor;
 pub mod r#false;
 mod getty;
 pub mod head;
@@ -41,6 +42,7 @@ pub use {
     bootstrap::{Bootstrap, BOOTSTRAP},
     dirname::{Dirname, DIRNAME},
     echo::{Echo, ECHO},
+    factor::{Factor, FACTOR},
     head::{Head, HEAD},
     nologin::{Nologin, NOLOGIN},
     r#false::{False, FALSE},
diff --git a/src/cmd/shitbox/mod.rs b/src/cmd/shitbox/mod.rs
index ebf689d..2e36137 100644
--- a/src/cmd/shitbox/mod.rs
+++ b/src/cmd/shitbox/mod.rs
@@ -1,4 +1,4 @@
-use super::{Cmd, BASE_32, BOOTSTRAP, DIRNAME, ECHO, FALSE, HEAD, HOSTNAME, NOLOGIN, SLEEP, TRUE};
+use super::{Cmd, BASE_32, BOOTSTRAP, DIRNAME, ECHO, FACTOR, FALSE, HEAD, HOSTNAME, NOLOGIN, SLEEP, TRUE};
 use clap::Command;
 use std::{
     error::Error,
@@ -35,6 +35,7 @@ impl Cmd for Shitbox {
                 DIRNAME.cli(),
                 ECHO.cli(),
                 FALSE.cli(),
+                FACTOR.cli(),
                 HEAD.cli(),
                 NOLOGIN.cli(),
                 HOSTNAME.cli(),
@@ -54,6 +55,7 @@ impl Cmd for Shitbox {
             Some(("bootstrap", matches)) => BOOTSTRAP.run(Some(matches))?,
             Some(("dirname", matches)) => DIRNAME.run(Some(matches))?,
             Some(("echo", _matches)) => ECHO.run(None)?,
+            Some(("factor", matches)) => FACTOR.run(Some(matches))?,
             Some(("false", _matches)) => FALSE.run(None)?,
             Some(("head", matches)) => HEAD.run(Some(matches))?,
             Some(("nologin", _matches)) => NOLOGIN.run(None)?,
diff --git a/src/lib.rs b/src/lib.rs
index 83920bc..bc43576 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -3,7 +3,7 @@ use std::{env, error::Error, path::PathBuf, string::ToString};
 
 pub mod cmd;
 use cmd::{
-    Cmd, Commands, BASE_32, BOOTSTRAP, DIRNAME, ECHO, FALSE, HEAD, HOSTNAME, NOLOGIN, SHITBOX, SLEEP, TRUE,
+    Cmd, Commands, BASE_32, BOOTSTRAP, DIRNAME, ECHO, FALSE, FACTOR, HEAD, HOSTNAME, NOLOGIN, SHITBOX, SLEEP, TRUE,
 };
 
 #[derive(Debug, Clone, Copy)]
@@ -39,7 +39,7 @@ pub fn run() -> Result<(), Box<dyn Error>> {
         cmd::COMMANDS
             .set(Commands {
                 items: vec![
-                    &BASE_32, &BOOTSTRAP, &DIRNAME, &ECHO, &FALSE, &HEAD, &HOSTNAME, &NOLOGIN, &TRUE, &SLEEP,
+                    &BASE_32, &BOOTSTRAP, &DIRNAME, &ECHO, &FALSE, &FACTOR, &HEAD, &HOSTNAME, &NOLOGIN, &TRUE, &SLEEP,
                     &SHITBOX,
                 ],
             })