use anyhow::Result;
use serde::Deserialize;

use crate::config::RuntimeConfig;

// This code is inspired by the Trunk crate (https://github.com/thedodd/trunk)

// This file parses the options that can be declared in the environment.
// runtime.rs applies business logic and builds RuntimeConfig structs.

/// Base configuration options
#[derive(Clone, Default, Deserialize)]
pub struct ConfigOptsBase {
  /// This node's private IP address [default: None]
  pub private_ip: Option<String>,
  /// Expiration time for IGD rules [default: 60]
  pub expiration_time: Option<u16>,
  /// Refresh time for IGD and Firewall rules [default: 300]
  pub refresh_time: Option<u16>,
  /// STUN server [default: stun.nextcloud.com:443]
  pub stun_server: Option<String>,
}

/// ACME configuration options
#[derive(Clone, Default, Deserialize)]
pub struct ConfigOptsAcme {
  /// Whether ACME is enabled [default: false]
  #[serde(default)]
  pub enable: bool,

  /// The default domain holder's e-mail [default: None]
  pub email: Option<String>,
}

/// Consul configuration options
#[derive(Clone, Default, Deserialize)]
pub struct ConfigOptsConsul {
  /// Consul's node name [default: None]
  pub node_name: Option<String>,
  /// Consul's REST URL [default: "http://127.0.0.1:8500"]
  pub url: Option<String>,
  /// Consul's CA certificate [default: None]
  pub ca_cert: Option<String>,
  /// Skip TLS verification for Consul server [default: false]
  #[serde(default)]
  pub tls_skip_verify: bool,
  /// Consul's client certificate [default: None]
  pub client_cert: Option<String>,
  /// Consul's client key [default: None]
  pub client_key: Option<String>,
}

/// Model of all potential configuration options
pub struct ConfigOpts {
  pub base: ConfigOptsBase,
  pub acme: ConfigOptsAcme,
  pub consul: ConfigOptsConsul,
}

impl ConfigOpts {
  pub fn from_env() -> Result<RuntimeConfig> {
    let base: ConfigOptsBase = envy::prefixed("DIPLONAT_").from_env()?;
    let consul: ConfigOptsConsul = envy::prefixed("DIPLONAT_CONSUL_").from_env()?;
    let acme: ConfigOptsAcme = envy::prefixed("DIPLONAT_ACME_").from_env()?;

    RuntimeConfig::new(Self {
      base: base,
      consul: consul,
      acme: acme,
    })
  }

  // Currently only used in tests
  #[cfg(test)]
  pub fn from_iter<Iter: Clone>(iter: Iter) -> Result<RuntimeConfig>
  where
    Iter: IntoIterator<Item = (String, String)>,
  {
    let base: ConfigOptsBase = envy::prefixed("DIPLONAT_").from_iter(iter.clone())?;
    let consul: ConfigOptsConsul = envy::prefixed("DIPLONAT_CONSUL_").from_iter(iter.clone())?;
    let acme: ConfigOptsAcme = envy::prefixed("DIPLONAT_ACME_").from_iter(iter.clone())?;

    RuntimeConfig::new(Self {
      base: base,
      consul: consul,
      acme: acme,
    })
  }
}