use crate::log_level::LogLevel;
use dirs::home_dir;
use structopt::StructOpt;

#[derive(StructOpt, Debug)]
pub struct FnmConfig {
    /// https://nodejs.org/dist/ mirror
    #[structopt(
        long,
        env = "FNM_NODE_DIST_MIRROR",
        default_value = "https://nodejs.org/dist"
    )]
    pub node_dist_mirror: reqwest::Url,

    /// The root directory of fnm installations.
    #[structopt(long = "fnm-dir", env = "FNM_DIR")]
    pub base_dir: Option<std::path::PathBuf>,

    /// Where the current node version link is stored
    #[structopt(long, env = "FNM_MULTISHELL_PATH")]
    multishell_path: Option<std::path::PathBuf>,

    /// The log level of fnm commands
    #[structopt(long, env = "FNM_LOGLEVEL", default_value = "info")]
    log_level: LogLevel,
}

impl Default for FnmConfig {
    fn default() -> Self {
        Self {
            node_dist_mirror: reqwest::Url::parse("https://nodejs.org/dist/").unwrap(),
            base_dir: None,
            multishell_path: None,
            log_level: LogLevel::Info,
        }
    }
}

impl FnmConfig {
    pub fn multishell_path(&self) -> Option<&std::path::Path> {
        match &self.multishell_path {
            None => None,
            Some(v) => Some(v.as_path()),
        }
    }

    pub fn log_level(&self) -> &LogLevel {
        &self.log_level
    }

    pub fn base_dir_with_default(&self) -> std::path::PathBuf {
        ensure_exists_silently(
            (self.base_dir.clone())
                .unwrap_or_else(|| home_dir().expect("Can't get home directory").join(".fnm")),
        )
    }

    pub fn installations_dir(&self) -> std::path::PathBuf {
        ensure_exists_silently(self.base_dir_with_default().join("node-versions"))
    }

    pub fn default_version_dir(&self) -> std::path::PathBuf {
        self.aliases_dir().join("default")
    }

    pub fn aliases_dir(&self) -> std::path::PathBuf {
        ensure_exists_silently(self.base_dir_with_default().join("aliases"))
    }

    #[cfg(test)]
    pub fn with_base_dir(mut self, base_dir: Option<std::path::PathBuf>) -> Self {
        self.base_dir = base_dir;
        self
    }
}

fn ensure_exists_silently<T: AsRef<std::path::Path>>(path: T) -> T {
    std::fs::create_dir_all(path.as_ref()).ok();
    path
}