feat: add help command #11

- add OPUS_HELP
- if opus is invoked without arguments, default feedback is now the 'opus ls' command
- if opus is invoked with not enough arguments for the given command, help will be displayed and opus exists

Author: xNaCly

src/cli.rs

@@ -1,6 +1,7 @@
 use crate::db::Database;
 use crate::types::{ArgumentType, Cli, CliInput, ExportType, Task};
 use chrono::Utc;
+use crate::util::OPUS_HELP;
 
 pub fn parse_args(args: Vec<String>) -> Cli {
     let mut r: Cli = Cli {
@@ -11,7 +12,17 @@ pub fn parse_args(args: Vec<String>) -> Cli {
         },
     };
 
+    if args.len() == 1 {
+        r.top_level_arg = ArgumentType::List;
+        r.input.query = Some("list".to_string());
+        return r;
+    }
+
     r.top_level_arg = match args[1].as_str() {
+        "help" | "h" => {
+            println!("{}", OPUS_HELP);
+            std::process::exit(1);
+        },
         "add" | "a" => ArgumentType::Add,
         "finish" | "f" => ArgumentType::Finish,
         "delete" | "d" => ArgumentType::Delete,
@@ -71,7 +82,10 @@ pub fn parse_args(args: Vec<String>) -> Cli {
             "Unknown Argument '{}', run 'opus help' for more info on command syntax.",
             args[1]
         ),
-        ArgumentType::Notenough => panic!("Not enough Arguments."),
+        ArgumentType::Notenough => {
+            println!("{}", OPUS_HELP);
+            panic!("Not enough Arguments.");
+        }
         _ => task = args[2].trim().split(' ').collect(),
     }
 

src/util.rs

@@ -4,6 +4,15 @@ use std::fs::create_dir;
 use std::path::Path;
 
 const CONFIG_PATH: &str = "/opus/opus.db";
+pub const OPUS_HELP: &str = "Usage: opus [command] [params]
+Commands:
+    list  \t<query>
+    add   \t<task> <tag> <priority> <date>
+    finish\t<id>
+    delete\t<id>
+    export\t<format> <filename>
+    clear
+";
 
 /// Get system dependent path to config files
 ///
@@ -56,3 +65,4 @@ pub fn create_dir_if_not_exist(path: &String) -> bool {
     }
     false
 }
+