use super::{
    Request,
    error,
    token,
    auth,
};
use crate::utils::Bool;

#[async_trait::async_trait]
trait Interface {
    fn client(&self) -> &reqwest::Client;
    fn url(&self, endpoint: &str) -> Result<reqwest::Url, url::ParseError>;
    fn current_token(&self) -> Option<std::sync::Arc<token::Token>>;
    async fn refresh_token(&self, api: Api) -> Result<Option<std::sync::Arc<token::Token>>, error::Token>;
}

#[derive(Debug)]
struct Internal<T: token::Provider> {
    client: reqwest::Client,
    base: reqwest::Url,
    token_provider: T,
}

impl<T: token::Provider> Internal<T> {
    fn new(client: reqwest::Client, base: reqwest::Url, token_provider: T)
        -> std::sync::Arc<Self> {
        std::sync::Arc::new(Self { client, base, token_provider })
    }

    #[tracing::instrument(skip_all, fields(endpoint=request.endpoint(), request, token))]
    async fn call<R: Request + Sized>(&self, request: &R, token: Option<&token::Token>) -> Result<R::Response, error::Api>
    {
        let url = self.base.join(request.endpoint()).map_err(error::Api::Url)?;
        let builder = self.client.request(R::METHOD, url);
        let builder = if let Some(token) = token {
            token.r#use(builder)
        } else {
            builder
        };
    
        let response = builder.json(request)
            .send()
            .await
            .map_err(error::Api::Reqwest)?;
    
        match response.status() {
            reqwest::StatusCode::OK => (),
            status => return Err(error::Api::Http(status)),
        }
        let result: R::Response = response.json().await?;
        Ok(result)
    }
}

async fn deserialize<R: Request>(response: reqwest::Response) -> Result<R::Response, error::Api>
{
    let response: R::Response = response.json().await.map_err(error::Api::Reqwest)?;
    Ok(response)
}

#[tracing::instrument(skip_all, fields(url, request, token))]
async fn call<R: Request>(client: &reqwest::Client, url: reqwest::Url, request: &R, token: Option<&token::Token>) -> Result<R::Response, error::Api> {
    let builder = client.request(R::METHOD, url);
    let builder = if let Some(token) = token {
        builder.bearer_auth(token.as_ref())
    } else {
        builder
    };
    let response = builder.json(request)
        .send()
        .await
        .map_err(error::Api::Reqwest)?;

    match response.status() {
        reqwest::StatusCode::OK =>
            deserialize::<R>(response).await,
        status => Err(error::Api::Http(status)),
    }
}

#[async_trait::async_trait]
impl<T: token::Provider> Interface for Internal<T> {
    fn client(&self) -> &reqwest::Client {
        &self.client
    }

    fn url(&self, endpoint: &str) -> Result<reqwest::Url, url::ParseError> {
        self.base.join(endpoint)
    }

    fn current_token(&self) -> Option<std::sync::Arc<token::Token>> {
        self.token_provider.current()
    }

    async fn refresh_token(&self, api: Api) -> Result<Option<std::sync::Arc<token::Token>>, error::Token> {
        self.token_provider.refresh(api).await
    }
}

#[derive(Debug)]
struct NoToken;

#[async_trait::async_trait]
impl token::Provider for NoToken {
    fn current(&self) -> Option<std::sync::Arc<token::Token>> {
        None
    }

    async fn refresh(&self, _api: Api) -> Result<Option<std::sync::Arc<token::Token>>, error::Token> {
        Ok(None)
    }
}

#[derive(Clone)]
pub struct Api(std::sync::Arc<dyn Interface + Sync + Send>);

impl Api {
    pub async fn new<A: auth::Provider>(auth: A) -> Result<Self, error::Api>
    {
        Self::new_with_base("https://api.spond.com", auth).await
    }

    pub async fn new_with_base<A: auth::Provider>(base: &str, auth: A) -> Result<Self, error::Api> {
        let base = reqwest::Url::parse(base)?;
        let host = base.host_str().unwrap().to_owned();

        let client = reqwest::Client::builder()
            //.https_only(true)
            .redirect(reqwest::redirect::Policy::limited(1))
            .retry(reqwest::retry::for_host(host)
                .max_retries_per_request(2)
                .classify_fn(|req_rep| {
                    use reqwest::StatusCode;
                    match req_rep.status() {
                        Some(StatusCode::UNAUTHORIZED) => req_rep.retryable(),
                        _ => req_rep.success(),
                    }
                }))
            // TODO
            //.cookie_store(true)
            .user_agent("spond-selection-bot")
            .read_timeout(std::time::Duration::from_secs(5))
            .connect_timeout(std::time::Duration::from_secs(15))
            .connection_verbose(true)
            .build()?;

        let api = Api(Internal::new(client.clone(), base.clone(), NoToken));
        let provider = auth.authenticate(api).await?;

        tracing::info!("{:?}", provider);
        let api = Api(Internal::new(client, base, provider));
        Ok(api)
    }


    pub async fn call<R: Request + Sized>(&self, request: &R) -> Result<R::Response, error::Api>
    {
        //async fn call<C: Call + ?Sized>(&self, api: &Api, call: &C, request: &C::Request) -> Result<C::Response, error::Call::<C>> {
        //    let mut token = self.token_provider.current();
        //    loop {
        //        match self.common.call(call, request, &token) {
        //            Err(error::Call::<C>::Http(reqwest::StatusCode::UNAUTHORIZED)) if token.is_some_and(|token|token.expired())
        //                => token = self.token_provider.refresh(api).map_err(error::Call::<C>::Token)?,
        //            result => return result,
        //        }
        //    }
        //}

        let client = self.0.client();
    
        if R::Authorization::VALUE == false {
            let url = self.0.url(request.endpoint())?;
            call(client, url, request, None).await
        } else {
            let mut current = self.0.current_token();
            loop {
                use std::ops::Deref;
                let token = if let Some(ref token) = current {
                    Some(token.deref())
                } else {
                    None
                };
                let url = self.0.url(request.endpoint())?;
                current = match call(client, url, request, token).await {
                    Err(error::Api::Http(reqwest::StatusCode::UNAUTHORIZED)) if current.is_some_and(|t|t.expired())
                        => self.0.refresh_token(self.clone()).await?,
                    result => break result,
                }
            }
        }
    }
}

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

    #[tokio::test]
    async fn mock() {}
}