use diesel::r2d2;
use diesel::prelude::*;
use diesel::pg::PgConnection;

use crate::models::*;

type ConnectionPool = r2d2::Pool<r2d2::ConnectionManager<PgConnection>>;

pub trait DataAccess {
    fn get_user_by_id(&self, id: u32) -> Option<UserAccount> {
        unimplemented!();
    }

    fn get_user_by_name(&self, username: String) -> Option<UserAccount> {
        unimplemented!();
    }
}

#[derive(Clone)]
pub struct DBAccess {
    connection_pool: ConnectionPool,
}

impl DBAccess {
    pub fn new(pool: ConnectionPool) -> DBAccess {
        DBAccess {
            connection_pool: pool,
        }
    }
}


impl DataAccess for DBAccess {
    fn get_user_by_name(&self, name: String) -> Option<UserAccount> {
        use elseware::schema::user_accounts::dsl::{user_accounts, username};
        self.connection_pool.get()
            .map(|conn| {
                user_accounts.filter(username.eq(name)).load::<UserAccount>(&conn)
                    .map(|mut user| user.pop()).unwrap_or(None)
            })
            .unwrap_or(None)
    }
}


/*impl DataAccess for DatabaseAccess {
}*/