pub mod db;

use axum::{
    body::Body,
    Json, 
    response::Response,
    Router,
    routing::{get, post}
};
use crate::AppError;
use db::{get_users, User};
use http::{header::HeaderMap, StatusCode};
use mongodb::bson::{doc, oid::ObjectId};

type ApiResult = Result<Response, AppError>;

pub fn router() -> Router {
    Router::new()
        .route("/sign-in",
            get(get_sign_in)
            .post(post_sign_in)
        )
        .route("/sign-up",
            post(post_sign_up))
        .route("/sign-out",
            post(post_sign_out))
        .route("/backup",
            post(post_backup)
        )
        .route("/restore",
            get(get_restore)
        )
}

pub async fn get_sign_in(Json(body): Json<User>) -> ApiResult {
    let db = get_users().await?;
    let query = doc! {
        "$expr": { "$eq": ["$username", body.username] }
    };

    match db.find_one(query, None).await? {
        Some(user) => {  
            Ok(Response::builder()
                .status(StatusCode::CREATED)
                .body(Body::from(user.auth.unwrap().salt.unwrap()))?)
        },
        None => {
            Ok(Response::builder()
                .status(StatusCode::NOT_FOUND)
                .body(Body::from("User does not exist"))?)
        }
    }
}

pub async fn post_sign_in(Json(body): Json<User>) -> ApiResult {
    let db = get_users().await?;
    let api = ObjectId::new();
    let query = doc! {
        "$expr": {
            "$and": [
            { "$eq": ["$username", body.username]},
            { "$eq": ["$_auth._hash", body.auth.unwrap_or_default().hash]}
            ]
        }
    };
    let update = doc! {
        "$set": {
            "_auth._api": api 
        }
    };

    match db.find_one(query.clone(), None).await? {
        Some(_user) => {
            db.update_one(query, update, None).await?;

            Ok(Response::builder()
                .status(StatusCode::OK)
                .body(Body::from(api.to_string()))?)
        },
        None => {
            Ok(Response::builder()
                .status(StatusCode::UNAUTHORIZED)
                .body(Body::from("Username or password is incorrect"))?)
        },
    }
}

pub async fn post_sign_up(Json(body): Json<User>) -> ApiResult {
    let db = get_users().await?;
    let auth = body.clone().auth.unwrap_or_default();
    let query = doc! {
        "$expr": {
            "$and": [
            { "$eq": ["$username", &body.username] },
            { "$eq": ["$_auth._hash", &auth.hash]},
            { "$eq": ["$_auth._salt", &auth.salt]}
            ]
        }
    };
    
    match db.find_one(query, None).await? {
        Some(_user) => {
            Ok(Response::builder()
                .status(StatusCode::NOT_ACCEPTABLE)
                .body(Body::from("Username is already taken"))?)
        },
        None => {
            db.insert_one(body, None).await?;

            Ok(Response::builder()
                .status(StatusCode::CREATED)
                .body(Body::from("Account created successfully"))?)
        }
    }
}


pub async fn post_sign_out(headers: HeaderMap) -> ApiResult {
    let db = get_users().await?;
    let api = headers["api_key"].to_str()?;

    let query = doc! {
        "$expr": { "$eq": ["$_auth._api", ObjectId::parse_str(api)?] }
    };
    let update = doc! {
        "$unset": {
            "_auth._api": ObjectId::new()
        }
    };

    match db.find_one(query.clone(), None).await? {
        Some(_user) => {
            db.update_one(query, update, None).await?;
            Ok(Response::builder()
                .status(StatusCode::OK)
                .body(Body::from("Sign out successful"))?)
        },
        None => {
            Ok(Response::builder()
                .status(StatusCode::NOT_ACCEPTABLE)
                .body(Body::from("User does not exist"))?)
        },
    }
}

pub async fn post_backup() {} //TODO: Backup

pub async fn get_restore() {} //TODO: restore