use crate::shell::{initialization, Init};
use colored::Colorize;

pub enum Status {
	Continue,
	Exit, // version, help, etc.
	Error,
}

pub fn handle_args(args: impl IntoIterator<Item = String>) -> Status {
	let mut iter = args.into_iter().peekable();
	let mut init = Init::new();
	if let Some(binary_path) = iter.next() {
		init.binary_path = binary_path;
	}

	if iter.peek().is_none() {
		return Status::Continue;
	}

	while let Some(arg) = iter.next() {
		match arg.as_str() {
			"-h" | "--help" => {
				print_help();
				return Status::Exit;
			}
			"-v" | "--version" => {
				print_version();
				return Status::Exit;
			}
			"-a" | "--alias" => match iter.peek() {
				Some(next_arg) if !next_arg.starts_with('-') => {
					init.alias = next_arg.to_string();
					iter.next();
				}
				_ => init.alias = String::from("f"),
			},
			"--nocnf" => init.cnf = false,
			_ => init.shell = arg,
		}
	}

	if init.shell.is_empty() {
		eprintln!("{}", t!("no-shell"));
		return Status::Error;
	}

	initialization(&mut init);
	Status::Exit
}

fn print_help() {
	println!(
		"{}",
		t!(
			"help",
			usage = "pay-respects <shell> [--alias [<alias>]] [--nocnf]",
			eval = "Bash / Zsh / Fish".bold(),
			eval_examples = r#"
eval "$(pay-respects bash)"
eval "$(pay-respects zsh)"
pay-respects fish | source
"#,
			manual = "Nushell / PowerShell".bold(),
			manual_examples = r#"
pay-respects nushell
pay-respects pwsh
"#
		)
	);
}

fn print_version() {
	println!(
		"version: {}",
		option_env!("CARGO_PKG_VERSION").unwrap_or("unknown")
	);
	let lib = option_env!("_DEF_PR_LIB").map(|dir| dir.to_string());
	if lib.is_some() {
		println!("Default lib directory: {}", lib.unwrap());
	}
}

#[cfg(test)]
mod tests {
	use super::{handle_args, Status};

	#[test]
	fn test_handle_args() {
		assert!(matches!(
			handle_args([String::from("pay-respects")]),
			Status::Continue
		));

		for args in [
			[String::new(), String::from("-h")],
			[String::new(), String::from("--help")],
			[String::new(), String::from("-v")],
			[String::new(), String::from("--version")],
			[String::new(), String::from("zsh")],
		] {
			println!("Arguments {:?} should return Exit", args);
			assert!(matches!(handle_args(args), Status::Exit));
		}

		for args in [
			[String::new(), String::from("fish"), String::from("--alias")],
			[String::new(), String::from("bash"), String::from("--nocnf")],
		] {
			println!("Arguments {:?} should return Exit", args);
			assert!(matches!(handle_args(args), Status::Exit));
		}

		for args in [
			[String::new(), String::from("-a")],
			[String::new(), String::from("--alias")],
			[String::new(), String::from("--nocnf")],
		] {
			println!("Arguments {:?} should return Error", args);
			assert!(matches!(handle_args(args), Status::Error));
		}

		for args in [
			[String::new(), String::from("-a"), String::from("--nocnf")],
			[
				String::new(),
				String::from("--alias"),
				String::from("--nocnf"),
			],
		] {
			println!("Argument {:?} should return Error", args);
			assert!(matches!(handle_args(args), Status::Error));
		}
	}
}
