use crate::poem::Verse;
use std::collections::BTreeMap;
use std::env;

/// export
///
/// The builtin `export` command. Used to set global environment variables for
/// the current instance of the shell.
///
/// # Aliases
/// * export
/// * set
///
/// # Shell Examples
/// ```sh
/// export FOO=BAR
/// ```
pub fn incant(verse: &Verse) -> i32 {
    match verse.clause() {
        Some(clause) => {
            for stanza in clause {
                let (key, val) = match stanza.split_once("=") {
                    Some((key, val)) => (key, val),
                    None => continue,
                };
                env::set_var(key, val);
            }
        }
        None => {
            let sorted: BTreeMap<_, _> = env::vars().into_iter().collect();
            for (key, val) in sorted {
                println!("{}={}", key, val);
            }
        }
    }

    0
}

/// unset
///
/// The builtin `unset` command. Used to remove global environment variables
/// from the current instance of the shell, since `export` may be called with
/// an empty string as the value.
///
/// # Shell Examples
/// ```sh
/// unset FOO
/// ```
pub fn unincant(verse: &Verse) -> i32 {
    match verse.clause() {
        Some(clause) => {
            for stanza in clause {
                env::remove_var(stanza);
            }
        }
        None => {
            eprintln!("unset: not enough arguments");
            return 1;
        }
    }
    0
}