From e3b9db70b3291c04d02301de4e2b81b8b1dc98c5 Mon Sep 17 00:00:00 2001
From: Yuto Nishida <starptr@users.noreply.github.com>
Date: Sun, 16 May 2021 18:00:22 -0700
Subject: [PATCH] Improve readability

---
 src/main.rs  | 24 +++++++++++++++++-------
 src/utils.rs | 36 ++++++++++++++++++++++++++++++++----
 2 files changed, 49 insertions(+), 11 deletions(-)

diff --git a/src/main.rs b/src/main.rs
index 6a294c2..9ef6d98 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,6 +1,6 @@
 mod utils;
 use utils::*;
-use clap::{App, Arg};
+use clap::{App, Arg, ArgGroup};
 
 fn main() {
     let arg_matches = App::new("pecho")
@@ -53,14 +53,15 @@ fn main() {
         )
         .arg(
                 Arg::with_name("color")
-                    .help("Specify color using an argument. Overrides single color options")
+                    .help("Specify color using an argument")
                     .short("c")
                     .long("color")
                     .takes_value(true)
+                    .possible_values(&COLORS)
             )
         .arg(
                 Arg::with_name("colorBg")
-                    .help("Specify background color using an argument. Overrides single color options")
+                    .help("Specify background color using an argument")
                     .short("C")
                     .long("color-bg")
                     .takes_value(true)
@@ -76,7 +77,7 @@ fn main() {
         )
         .arg(
             Arg::with_name("truecolor")
-                .help("Hex color in xxxxxx format. Overrides other color options")
+                .help("Hex color in xxxxxx format")
                 .short("t")
                 .long("truecolor")
                 .takes_value(true)
@@ -84,12 +85,21 @@ fn main() {
         )
         .arg(
             Arg::with_name("truecolorBg")
-                .help("Background in hex in xxxxxx format. Overrides other color options")
+                .help("Background in hex in xxxxxx format")
                 .short("T")
                 .long("truecolor-bg")
                 .takes_value(true)
                 .value_name("hex"),
         )
+        .group(ArgGroup::with_name("specific")
+            .args(&["black", "red", "green", "yellow", "blue", "purple", "cyan", "white",
+                "blackBg", "redBg", "greenBg", "yellowBg", "blueBg", "purpleBg", "cyanBg", "whiteBg",]))
+        .group(ArgGroup::with_name("generic")
+            .args(&["color", "colorBg"])
+            .conflicts_with("specific"))
+        .group(ArgGroup::with_name("trueGeneric")
+            .args(&["truecolor", "truecolorBg"])
+            .conflicts_with_all(&["specific", "generic"]))
         .get_matches();
 
     // Concatenate input into space-separated words
@@ -98,9 +108,9 @@ fn main() {
     // Replace escaped special characters and add trailing newline if necessary
     let std_print_string = special_chars_and_newlines(input, arg_matches.is_present("noEscapes"), arg_matches.is_present("noNewline"));
 
-    let std_print_string = add_color(std_print_string, &arg_matches, false);
+    let std_print_string = add_color_fg(std_print_string, &arg_matches);
 
-    let std_print_string = add_color(std_print_string.to_string(), &arg_matches, true);
+    let std_print_string = add_color_bg(std_print_string.to_string(), &arg_matches);
 
     let std_print_string = add_style(std_print_string, &arg_matches);
 
diff --git a/src/utils.rs b/src/utils.rs
index 4df833d..11405a7 100644
--- a/src/utils.rs
+++ b/src/utils.rs
@@ -4,10 +4,30 @@ use lazy_static::*;
 use regex::Regex;
 use std::char;
 
-const COLORS: [&str; 8] = [
+enum PechoErr {
+    NoMatch,
+    InvalidHex,
+}
+
+pub const COLORS: [&str; 8] = [
     "black", "red", "green", "yellow", "blue", "purple", "cyan", "white",
 ];
 
+// convert a color string to a Color enum
+fn parse_color(s: &str) -> Result<Color, PechoErr>{
+    match s {
+        "black" => Ok(Color::Black),
+        "red" => Ok(Color::Red),
+        "green" => Ok(Color::Green),
+        "yellow" => Ok(Color::Yellow),
+        "blue" => Ok(Color::Blue),
+        "purple" => Ok(Color::Magenta),
+        "cyan" => Ok(Color::Cyan),
+        "white" => Ok(Color::White),
+        _ => Err(PechoErr::NoMatch),
+    }
+}
+
 // turn iterable of input into a string of space-separated words
 pub fn args_to_input(values: Option<Values>) -> String {
     match values {
@@ -115,18 +135,26 @@ fn is_valid_hex(s: &str) -> bool {
     RE.is_match(s)
 }
 
-pub fn hex_to_dectuple(hex: &str) -> Result<(u8, u8, u8), &str> {
+fn hex_to_dectuple(hex: &str) -> Result<(u8, u8, u8), PechoErr> {
     if is_valid_hex(&hex) {
         let first = u8::from_str_radix(&hex[0..2], 16).unwrap();
         let second = u8::from_str_radix(&hex[2..4], 16).unwrap();
         let third = u8::from_str_radix(&hex[4..6], 16).unwrap();
         Ok((first, second, third))
     } else {
-        Err("Not a valid hex")
+        Err(PechoErr::InvalidHex)
     }
 }
 
-pub fn add_color(input: String, arg_matches: &ArgMatches, is_bg: bool) -> ColoredString {
+pub fn add_color_fg(input: String, arg_matches: &ArgMatches) -> ColoredString {
+    add_color(input, arg_matches, false)
+}
+
+pub fn add_color_bg(input: String, arg_matches: &ArgMatches) -> ColoredString {
+    add_color(input, arg_matches, true)
+}
+
+fn add_color(input: String, arg_matches: &ArgMatches, is_bg: bool) -> ColoredString {
     let suffix = if is_bg { "Bg" } else { "" };
     if let Some(hex) = arg_matches.value_of("truecolor".to_owned() + suffix) {
         if let Ok(truecolor_args) = hex_to_dectuple(&hex) {