use anyhow::*;
use log::LevelFilter;
use northstar::{
    GEMINI_PORT,
    Document,
    Request,
    Response,
    Server,
    user_management::{
        User,
        UserManagementRoutes,
    },
};

#[tokio::main]
/// An ultra-simple demonstration of authentication.
///
/// The user should be able to set a secret string that only they can see.  They should be
/// able to change this at any time to any thing.  Both the string and the user account
/// will persist across restarts.
///
/// This method sets up and starts the server
async fn main() -> Result<()> {
    // Turn on logging
    env_logger::builder()
        .filter_module("northstar", LevelFilter::Debug)
        .init();

    Server::bind(("0.0.0.0", GEMINI_PORT))

        // Add our main routes
        .add_route("/", handle_main)
        .add_route("/update", handle_update)

        // Add routes for handling user authentication
        .add_um_routes::<String>("/")

        // Start the server
        .serve()
        .await
}

/// The landing page
///
/// Displays the user's current secret string, or prompts the user to sign in if they
/// haven't.  Includes links to update your string (`/update`) or your account
/// (`/account`).  Even though we haven't added an explicit handler for `/account`, this
/// route is managed by northstar.
async fn handle_main(request: Request) -> Result<Response> {

    // Check to see if the user is signed in.  If they are, we get a copy of their data
    // (just a simple [`String`] for this demo, but this can be any serializable struct.
    if let User::SignedIn(user) = request.user::<String>()? {

        // If the user is signed in, render and return their page
        let response = Document::new()
            .add_text("Your personal secret string:")
            .add_text(user.as_ref())
            .add_blank_line()
            .add_link("/update", "Change your string")
            .add_link("/account", "Update your account")
            .into();
        Ok(response)

    } else {

        // If the user is not logged in, prompt them to go to /account
        let response = Document::new()
            .add_text("Please login to use this app.")
            .add_blank_line()
            .add_link("/account", "Login or create account")
            .into();
        Ok(response)

    }
}

/// The update endpoint
///
/// Users can update their secret string here.  Users who haven't logged in will be
/// promped to do so.
async fn handle_update(request: Request) -> Result<Response> {

    // Check if the user is signed in again
    if let User::SignedIn(mut user) = request.user::<String>()? {

        // If the user is logged in, check to see if they provided any input.  If they
        // have, we can set that input as their new string, otherwise we ask them for it
        if let Some(string) = request.input() {

            // Update the users data
            *user.as_mut() = string.to_owned();

            // Render a response
            let response = Document::new()
                .add_text("String updated!")
                .add_blank_line()
                .add_link("/", "Back")
                .into();
            Ok(response)

        } else {

            // Ask the user for some input
            Ok(Response::input_lossy("Enter your new string"))

        }
    } else {

        // The user isn't logged in, so we should ask them too
        let response = Document::new()
            .add_text("Please login to use this app.")
            .add_blank_line()
            .add_link("/account", "Login or create account")
            .into();
        Ok(response)

    }
}