use std::path::{Path, PathBuf};

use clap::{Parser, ValueEnum};

use crate::constants::{APP_NAME, CLIENTS_LIST_FILE, USERS_LIST_FILE};

#[derive(ValueEnum, Default, Debug, Clone, Eq, PartialEq)]
pub enum UsersBackend {
    #[default]
    File,
    Ldap,
}

#[derive(Debug, Clone)]
pub struct LdapConfiguration {
    server_uri: &'static str,
    bind_dn: &'static str,
    bind_password: &'static str,
    start_tls: bool,
    root_dn: &'static str,
    attr_map: &'static str,
}

/// Basic OIDC provider
#[derive(Parser, Debug, Clone)]
#[clap(author, version, about, long_about = None)]
pub struct AppConfig {
    /// Listen address
    #[clap(short, long, env, default_value = "0.0.0.0:8000")]
    pub listen_address: String,

    /// Storage path
    #[clap(short, long, env)]
    pub storage_path: String,

    /// App token token
    #[clap(short, long, env, default_value = "")]
    pub token_key: String,

    /// Website origin
    #[clap(short, long, env, default_value = "http://localhost:8000")]
    pub website_origin: String,

    /// Proxy IP, might end with a star "*"
    #[clap(short, long, env)]
    pub proxy_ip: Option<String>,

    /// IP location service API
    ///
    /// Up instance of IP location service : <https://gitlab.com/pierre42100/iplocationserver>
    ///
    /// Example: "<https://api.geoip.rs>"
    #[clap(long, short, env)]
    pub ip_location_service: Option<String>,

    /// Users source backend
    #[clap(value_enum, long, short, default_value = "file")]
    pub backend: UsersBackend,

    /// LDAP server URI
    #[clap(
        long,
        env,
        group = "ldap-server-uri",
        requires = "ldap-dn",
        requires = "ldap-password"
    )]
    pub ldap_server_uri: Option<String>,

    /// LDAP user DN to bind as to perform searches
    #[clap(long, env, group = "ldap-dn", requires = "ldap-server-uri")]
    pub ldap_dn: Option<String>,

    /// LDAP user DN to bind as to perform searches
    #[clap(long, env, group = "ldap-password", requires = "ldap-server-uri")]
    pub ldap_password: Option<String>,

    // /// The LDAP user filter, using `{0}` as the username placeholder, e.g. `(|(cn={0})(mail={0}))`;
    // /// uses standard LDAP search syntax. Default: `(uid={0})`.
    // #[clap(long, env, default_value = "uid={0}")]
    // pub ldap_search_filter: String,
    /// Set this argument to enable LDAP StartTLS support. (disabled by default)
    #[clap(long, env, default_value_t = false)]
    pub ldap_start_tls: bool,

    /// The LDAP search root DN, e.g. `dc=my,dc=domain,dc=com;` supports multiple entries in a
    /// space-delimited list, e.g. `dc=users,dc=domain,dc=com dc=admins,dc=domain,dc=com.`
    #[clap(long, env, requires = "ldap-server-uri")]
    pub ldap_root_dn: Option<String>,

    /// A mapping of user attributes to LDAP values
    #[clap(
        long,
        env,
        default_value = "first_name:givenName,last_name:sn,username:uid,email:mail"
    )]
    pub ldap_attr_map: String,
}

lazy_static::lazy_static! {
    static ref ARGS: AppConfig = {
        let mut config = AppConfig::parse();

        // In debug mode only, use dummy token
        if cfg!(debug_assertions) && config.token_key.is_empty() {
            config.token_key = String::from_utf8_lossy(&[32; 64]).to_string();
        }

        config
    };
}

impl AppConfig {
    /// Get parsed command line arguments
    pub fn get() -> &'static AppConfig {
        &ARGS
    }

    pub fn secure_cookie(&self) -> bool {
        self.website_origin.starts_with("https:")
    }

    pub fn storage_path(&self) -> &Path {
        self.storage_path.as_ref()
    }

    pub fn users_file(&self) -> PathBuf {
        self.storage_path().join(USERS_LIST_FILE)
    }

    pub fn clients_file(&self) -> PathBuf {
        self.storage_path().join(CLIENTS_LIST_FILE)
    }

    pub fn full_url(&self, uri: &str) -> String {
        if uri.starts_with('/') {
            format!("{}{}", self.website_origin, uri)
        } else {
            format!("{}/{}", self.website_origin, uri)
        }
    }

    pub fn domain_name(&self) -> &str {
        self.website_origin.split('/').nth(2).unwrap_or(APP_NAME)
    }

    /// Get LDAP configuration, if available
    pub fn ldap_config(&'static self) -> LdapConfiguration {
        assert_eq!(self.backend, UsersBackend::Ldap);
        LdapConfiguration {
            server_uri: self.ldap_server_uri.as_deref().unwrap(),
            bind_dn: self.ldap_dn.as_deref().unwrap(),
            bind_password: self.ldap_password.as_deref().unwrap(),
            start_tls: self.ldap_start_tls,
            root_dn: self.ldap_root_dn.as_deref().unwrap(),
            attr_map: self.ldap_attr_map.as_str(),
        }
    }
}

#[cfg(test)]
mod test {
    use crate::data::app_config::AppConfig;

    #[test]
    fn verify_cli() {
        use clap::CommandFactory;
        AppConfig::command().debug_assert()
    }
}