use std::cell::RefCell;
use std::collections::HashMap;

use light_openid::primitives::{OpenIDConfig, OpenIDTokenResponse, OpenIDUserInfo};

use crate::actors::providers_states_actor::ProviderLoginState;
use crate::constants::OIDC_PROVIDERS_LIFETIME;
use crate::data::app_config::AppConfig;

use crate::data::provider::Provider;
use crate::utils::err::Res;
use crate::utils::time::time;

/// Provider configuration
#[derive(Debug, Clone)]
pub struct ProviderConfiguration {
    pub discovery: OpenIDConfig,
    pub expire: u64,
}

impl ProviderConfiguration {
    /// Get the URL where a user should be redirected to authenticate
    pub fn auth_url(&self, provider: &Provider, state: &ProviderLoginState) -> String {
        let authorization_url = &self.discovery.authorization_endpoint;
        let client_id = urlencoding::encode(&provider.client_id).to_string();
        let state = urlencoding::encode(&state.state_id).to_string();
        let callback_url = AppConfig::get().oidc_provider_redirect_url();

        format!("{authorization_url}?response_type=code&scope=openid%20profile%20email&client_id={client_id}&state={state}&redirect_uri={callback_url}")
    }

    /// Retrieve the authorization token after a successful authentication, using an authorization code
    pub async fn get_token(
        &self,
        provider: &Provider,
        authorization_code: &str,
    ) -> Res<OpenIDTokenResponse> {
        let (token, _) = self
            .discovery
            .request_token(
                &provider.client_id,
                &provider.client_secret,
                authorization_code,
                &AppConfig::get().oidc_provider_redirect_url(),
            )
            .await?;

        Ok(token)
    }

    /// Retrieve information about the user, using a given [OpenIDTokenResponse]
    pub async fn get_userinfo(&self, token: &OpenIDTokenResponse) -> Res<OpenIDUserInfo> {
        Ok(self.discovery.request_user_info(token).await?.0)
    }
}

thread_local! {
    static THREAD_CACHE: RefCell<HashMap<String, ProviderConfiguration>> = RefCell::new(Default::default());
}

pub struct ProviderConfigurationHelper {}

impl ProviderConfigurationHelper {
    /// Get or refresh the configuration for a provider
    pub async fn get_configuration(provider: &Provider) -> Res<ProviderConfiguration> {
        let config = THREAD_CACHE.with(|i| i.borrow().get(&provider.configuration_url).cloned());

        // Refresh config cache if needed
        if config.is_none() || config.as_ref().unwrap().expire < time() {
            let conf = Self::fetch_configuration(provider).await?;

            THREAD_CACHE.with(|i| {
                i.borrow_mut()
                    .insert(provider.configuration_url.clone(), conf.clone())
            });

            return Ok(conf);
        }

        // We can return immediately previously extracted value
        Ok(config.unwrap())
    }

    /// Get fresh configuration from provider
    async fn fetch_configuration(provider: &Provider) -> Res<ProviderConfiguration> {
        Ok(ProviderConfiguration {
            discovery: OpenIDConfig::load_from_url(&provider.configuration_url).await?,
            expire: time() + OIDC_PROVIDERS_LIFETIME,
        })
    }
}