offline-web/exp1/src/serve.rs

use std::{collections::HashMap, sync::Arc};

use axum::{extract::Path, http, response::{Html, IntoResponse}, routing::get, Json, Router};
use blake2::{Blake2b512, Digest};
use rand::Rng;

use offline_web_model::Reference;

#[derive(Debug)]
pub struct AddressableObject {
    pub address: String,
    pub content: String,
}

fn random_object() -> AddressableObject {
    let mut rng = rand::rng();
    let random_size = rng.random_range(50..=4096);
    let random_string: String = (0..random_size)
        .map(|_| rng.sample(rand::distr::Alphanumeric) as char)
        .collect();

    let mut hasher = Blake2b512::new();
    hasher.update(&random_string);
    let hash = format!("{:x}", hasher.finalize());

    AddressableObject {
        address: hash,
        content: random_string,
    }
}

fn random_references_and_objects() -> (Arc<Reference>, Arc<HashMap<String, Arc<Reference>>>, Arc<HashMap<String, AddressableObject>>) {
    let path_root = String::from("ref/0");
    let mut objects = HashMap::new();
    let mut refs = HashMap::new();
    let mut root_ref = Reference::new(
        "username:0".to_string(),
        String::from("0"),
        path_root.clone(),
    );
    let mut root_hasher = Blake2b512::new();
    for i in 1..=10 {
        let mut item_ref = Reference::new(
            format!("item:{}", i),
            format!("0:{}", i),
            format!("/item/{}", i),
        );
        let mut hasher = Blake2b512::new();
        for j in 1..=10 {
            let object = random_object();
            hasher.update(&object.content);
            let leaf_ref = Reference::new(
                format!("item:{}:subitem:{}", i, j),
                format!("{}", object.address),
                format!("/item/{}/subitem/{}", i, j),
            ).to_arc();
            item_ref = item_ref.add_dep(leaf_ref.clone());
            objects.insert(object.address.clone(), object);
            hasher.update(&leaf_ref.content_address);
            refs.insert(leaf_ref.path.clone(), leaf_ref);
        }
        let hash = format!("{:x}", hasher.finalize());
        item_ref.content_address = hash;
        root_hasher.update(&item_ref.content_address);
        let rc_ref = item_ref.to_arc();
        root_ref = root_ref.add_dep(rc_ref.clone());
        refs.insert(rc_ref.path.clone(), rc_ref);
    }
    root_ref.content_address = format!("{:x}", root_hasher.finalize());
    let rc_root = root_ref.to_arc();
    refs.insert(rc_root.path.clone(), rc_root.clone());
    dbg!(&objects);
    (rc_root, Arc::new(refs), Arc::new(objects))
}

// TODO(jeremy): Allow this to autoexpand the content_addresses?
async fn all_references(root_ref: Arc<Reference>) -> Json<Arc<Reference>> {
    Json(root_ref)
}

async fn ref_path(refs: Arc<HashMap<String, Arc<Reference>>>, Path(path): Path<String>) -> Json<Arc<Reference>> {
    let path = format!("/item/{}", path);
    match refs.get(&path) {
        Some(r) => Json(r.clone()),
        None => todo!("Return a 404?"),
    }
}

async fn object_path(objects: Arc<HashMap<String, AddressableObject>>, Path(addr): Path<String>) -> String {
    dbg!(&addr);
    match objects.get(&addr) {
        Some(o) => o.content.clone(),
        None => todo!("Return a 404?"),
    }
}

async fn get_client_js() -> impl IntoResponse {
    (
        [(http::header::CONTENT_TYPE, "application/javascript")],
        include_str!("../static/client.js"),
    )
}

pub fn endpoints(root_ref: Arc<Reference>, refs: Arc<HashMap<String, Arc<Reference>>>, objects: Arc<HashMap<String, AddressableObject>>) -> Router {
    Router::new().nest(
        "/api/v1",
        Router::new().nest(
            "/ref",
            Router::new()
                .route("/all/username", get({
                    let state = root_ref.clone();
                    move || all_references(state)
                }))
                .route("/item/{*path}", get({
                    let refs = refs.clone();
                    move |path| ref_path(refs, path)
                }))
        ).nest(
            "/object",
            Router::new()
                .route("/{addr}", get({
                        let objects = objects.clone();
                        move |addr| object_path(objects, addr)
                }))
        ),
    )
    .route("/lib/client.js", get(get_client_js))
    .route("/ui/", get(|| async { Html(include_str!("../static/index.html")).into_response() }))
}

// TODO(jwall): Javascript test script
pub async fn serve() {
    // run our app with hyper, listening globally on port 3000
    let (root_ref, refs, objects) = random_references_and_objects();
    let listener = tokio::net::TcpListener::bind("127.0.0.1:3000")
        .await
        .unwrap();
    println!("Server ui starting on http://127.0.0.1:3000/ui/");
    axum::serve(listener, endpoints(root_ref, refs, objects)).await.unwrap();
}