use std::env::args;
use std::io::Result;
use super::available_commands;

pub struct Help;

impl Help {
    pub fn new() -> Self {
        Help
    }
}

impl super::Command for Help {
    fn before_dependencies(&self) -> Vec<Box<dyn super::Command>> {
        vec![]
    }

    fn execute(&self, _: Option<&String>) -> Result<()> {
        let arguments: Vec<String> = args().collect();
        let app_name = arguments.get(0).map_or("blog", |s| s.as_str());
        let commands = available_commands();
        println!("Usage:");
        println!("");
        for command in commands {
            print!("{} {} ", app_name, command.command());
            println!("{}", command.help());
        }
        return Ok(())
    }

    fn after_dependencies(&self) -> Vec<Box<dyn super::Command>> {
        vec![]
    }

    fn command(&self) -> &'static str {
        "help"
    }

    fn help(&self) -> &'static str {
        "\t\t\t\tPrints this help"
    }
}