use std::time::SystemTime;

use axum::{
    debug_handler,
    extract::State,
    response::{IntoResponse, Response},
};
use http::{HeaderMap, StatusCode};

use crate::{
    models::{ApiResponse, AppError, Session},
    requests::AppState,
    services::{
        auth_token::{self, generate_session_token, get_if_auth_token_exists, verify_token},
        user_session,
    },
};

use super::models::AuthSessionResponse;

#[debug_handler]
pub async fn auth_session_get_handler(
    State(state): State<AppState>,
    headers: HeaderMap,
) -> Result<Response, AppError> {
    let cache_pool = state.cache_pool();
    let token_key = state.env().token_key();

    let auth_token_str = auth_token::extract_token_string_from_http_headers(&headers)?;
    let auth_token = verify_token(token_key, auth_token_str, None)?;

    let user_id = auth_token
        .payload_claims()
        .and_then(|claims| claims.get_claim("sub"))
        .and_then(|user_id| user_id.as_str())
        .ok_or(AppError::invalid_token())
        .and_then(|user_id| {
            user_id
                .parse::<i32>()
                .map_err(|_| AppError::invalid_token())
        })
        .unwrap();

    let auth_token_exists =
        get_if_auth_token_exists(cache_pool, user_id, auth_token_str.to_string().as_str()).await?;

    if !auth_token_exists {
        return Err(AppError::no_session_found());
    }

    let (session_token, session_token_id, session_token_expiration) =
        generate_session_token(token_key, user_id);

    let expiration = session_token_expiration
        .duration_since(SystemTime::now())
        .unwrap();

    let new_session = Session {
        user_id,
        created_at: SystemTime::now(),
        expires_at: session_token_expiration,
    };

    user_session::store_user_session(cache_pool, session_token_id, new_session, Some(expiration))
        .await?;

    Ok((
        StatusCode::CREATED,
        ApiResponse::new(AuthSessionResponse {
            token: session_token,
            expiration: session_token_expiration,
        })
        .into_json_response(),
    )
        .into_response())
}