use std::env;

pub const KEYRING_SERVICE: &str = "system-update";
pub const KEYRING_ACCOUNT: &str = "api-token";

pub fn keyring_identity() -> (&'static str, &'static str) {
    (KEYRING_SERVICE, KEYRING_ACCOUNT)
}

#[derive(Debug, Clone, PartialEq, Eq)]
pub enum TokenSource {
    CliArgument(String),
    Environment(Option<String>),
}

impl TokenSource {
    pub fn from_env() -> Self {
        Self::Environment(env::var("SYSTEM_UPDATE_TOKEN").ok())
    }

    pub fn load(self) -> Option<String> {
        match self {
            Self::CliArgument(token) => clean_token(token),
            Self::Environment(token) => token.and_then(clean_token),
        }
    }
}

fn clean_token(token: String) -> Option<String> {
    let trimmed = token.trim().to_string();
    if trimmed.is_empty() {
        None
    } else {
        Some(trimmed)
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn trims_cli_token() {
        assert_eq!(
            TokenSource::CliArgument(" su_token ".to_string()).load(),
            Some("su_token".to_string())
        );
    }

    #[test]
    fn ignores_empty_token() {
        assert_eq!(TokenSource::CliArgument(" ".to_string()).load(), None);
    }

    #[test]
    fn documents_future_keyring_identity() {
        assert_eq!(keyring_identity(), ("system-update", "api-token"));
    }
}