// Run an upstream HTTP server on 127.0.0.1:8001, then request /busy, /wait and
// /fast on port 8000. The window keeps drawing while the handlers share turns.
import core::raylib;
import core::http;

record State { frames: i64, busy: bool, fast: bool, conflict: bool }

fn outbound(ctx: http::Context<string,State>, saved: i64) -> http::ServerResponse {
    let snapshot = http::snapshot_state(ctx);
    let request = http::client_request("GET", http::read_config(ctx))::value;
    let reply = http::request(request, http::client_options());
    if not reply::ok {
        return http::text_response(502, reply::error::code, "text/plain")::value;
    }
    if saved not matches 7 { return http::response(500, [])::value; }
    let published = http::replace_state_if_current(ctx, snapshot, snapshot::value)::value;
    var current = http::read_state(ctx);
    current::conflict = not published;
    http::replace_state(ctx, current);
    return http::text_response(200, "conflict", "text/plain")::value;
}

fn handler(req: http::IncomingRequest, ctx: http::Context<string,State>) -> http::ServerResponse {
    if req::path matches "/busy" {
        var state = http::read_state(ctx);
        state::busy = true;
        http::replace_state(ctx, state);
        while true {}
    }
    if req::path matches "/wait" { return outbound(ctx, 7); }
    var current = http::read_state(ctx);
    current::fast = raylib::IsWindowReady();
    http::replace_state(ctx, current);
    return http::text_response(200, "fast", "text/plain")::value;
}

fn start_main() -> i64 {
    let opened = raylib::InitWindow(480, 240, "ASPL HTTP and drawing");
    if not opened::ok { print(opened::error::code); return 1; }
    let pacing = raylib::SetTargetFPS(60);
    if not pacing::ok { return 9; }
    var server = http::server_config();
    server::listeners = [http::listener("127.0.0.1", 8000)::value];
    let routes = http::router([
        http::route("GET", "/busy", handler)::value,
        http::route("GET", "/wait", handler)::value,
        http::route("GET", "/fast", handler)::value
    ])::value;
    let started = http::start(server, routes, "http://127.0.0.1:8001/",
        State {frames: 0, busy: false, fast: false, conflict: false});
    if not started::ok { print(started::error::code); return 2; }
    let owner = started::value;
    print("ready\n");
    var budget = http::progress_budget();
    budget::max_instructions = 128;
    var frames: i32 = 0;
    while frames < 180 and not raylib::WindowShouldClose()::value {
        if not http::progress(owner, budget)::ok { return 3; }
        if not raylib::BeginDrawing()::ok { return 4; }
        if not raylib::ClearBackground(raylib::RAYWHITE)::ok { return 10; }
        var state = http::snapshot_session_state(owner)::value::value;
        state::frames = state::frames + 1;
        if not http::replace_session_state(owner, state)::ok { return 5; }
        if not raylib::DrawRectangle(frames, 90, 40, 40, raylib::BLUE)::ok { return 11; }
        if not raylib::EndDrawing()::ok { return 6; }
        frames = frames + 1;
    }
    let final = http::session_state(owner)::value;
    if not http::close_session(owner)::ok { return 7; }
    if not raylib::CloseWindow()::ok { return 8; }
    if final::busy and final::fast and final::conflict {
        print("busy fast conflict\n");
    }
    return 0;
}