//! Runtime validation: boot full plugin stack with real content, tick 10
//! times over TCP, assert valid ObserverSnapshot (#489).
//!
//! Separated from content_loading.rs (structural loading tests) per
//! architectural review — TCP runtime tests have different failure modes
//! and timeout characteristics.

use bevy_app::prelude::*;
use std::net::{TcpListener, TcpStream};
use std::path::PathBuf;
use std::sync::{Arc, Barrier};
use std::thread;
use std::time::Duration;

use settled_reach_server::bridge::framing::{read_framed, write_framed};
use settled_reach_server::bridge::tcp::TcpBridge;
use settled_reach_server::bridge::types::*;
use settled_reach_server::bridge::{BridgePlugin, BridgeResource};
use settled_reach_server::content::{ContentConfig, ContentPlugin};
use settled_reach_server::knowledge::registry::EntityRegistry;
use settled_reach_server::knowledge::KnowledgeGraph;
use settled_reach_server::perception::cognitive_delay::CognitiveDelay;
use settled_reach_server::perception::vision_cone::Facing;
use settled_reach_server::simulation::interaction::NearbyInteractionBuffer;
use settled_reach_server::simulation::listening::ListeningFocus;
use settled_reach_server::simulation::monologue::{
    MonologueBuffer, MonologueState, SprintAnomalyQueue,
};
use settled_reach_server::simulation::movement::{PlayerCharacter, TilePosition, WalkabilityMap};
use settled_reach_server::simulation::stance::{MovementProfile, PlayerMoveCooldown};
use settled_reach_server::simulation::SimulationPlugin;

fn content_root() -> PathBuf {
    let manifest_dir = env!("CARGO_MANIFEST_DIR");
    PathBuf::from(manifest_dir).join("../content")
}

/// Smoke test for production content. Boots the full plugin stack with real
/// content over TCP, ticks 10 times, and asserts a valid ObserverSnapshot.
/// Catches runtime panics from broken entity references, missing components,
/// or content schema issues that pass YAML validation but fail at tick time.
#[test]
fn content_runtime_boot_tick_10_snapshot() {
    use std::io::{BufReader, BufWriter};

    let root = content_root();
    if !root.join("content.yaml").exists() {
        eprintln!("Skipping: content directory not found at {:?}", root);
        return;
    }

    let listener = TcpListener::bind("127.0.0.1:0").expect("bind listener");
    let server_addr = listener.local_addr().expect("get local addr");

    // Barrier keeps the server thread alive until the client has finished
    // reading all snapshots, preventing a TCP RST race under parallel execution.
    let barrier = Arc::new(Barrier::new(2));
    let server_barrier = barrier.clone();

    // Server thread: full plugin stack with real content
    let server_handle = thread::spawn(move || {
        let bridge = TcpBridge::accept_on(listener).expect("accept connection");

        let mut app = App::new();
        app.add_plugins(SimulationPlugin);
        app.add_plugins(BridgePlugin);
        app.add_plugins(settled_reach_server::knowledge::KnowledgePlugin);
        app.add_plugins(settled_reach_server::npc::NpcPlugin);
        app.insert_resource(ContentConfig {
            content_root: root,
            ..Default::default()
        });
        app.add_plugins(ContentPlugin);
        app.insert_resource(BridgeResource::new(bridge));
        app.insert_resource(WalkabilityMap::new(32, 32, 1));

        // Spawn player with all required observer pipeline components
        let profile = MovementProfile::smuggler();
        let mut registry = EntityRegistry::new(0);
        let player = app
            .world_mut()
            .spawn((
                PlayerCharacter,
                TilePosition::new(16, 16, 0),
                Facing::default(),
                KnowledgeGraph::new(),
                NearbyInteractionBuffer::default(),
                MonologueState::default(),
                MonologueBuffer::default(),
                SprintAnomalyQueue::default(),
                CognitiveDelay::default(),
                ListeningFocus::new(TilePosition::new(16, 16, 0)),
                profile,
                profile.initial_stance(),
                PlayerMoveCooldown::default(),
            ))
            .id();
        registry.register(player);
        app.insert_resource(registry);

        // Tick 10 times — any panic here means content has a runtime bug
        for _ in 0..10 {
            app.update();
        }

        // Wait for client to finish reading before dropping the TCP socket
        server_barrier.wait();
    });

    // Client: connect with read timeout and receive 10 snapshots
    let stream = TcpStream::connect(server_addr).expect("client connect");
    stream
        .set_read_timeout(Some(Duration::from_secs(10)))
        .expect("set read timeout");
    let mut reader = BufReader::new(stream.try_clone().expect("clone for reader"));
    let mut writer = BufWriter::new(stream);

    let mut last_snapshot = None;
    for tick in 0..10 {
        let payload = read_framed(&mut reader)
            .unwrap_or_else(|e| panic!("read error at tick {}: {}", tick, e))
            .unwrap_or_else(|| panic!("unexpected EOF at tick {}", tick));

        let snapshot: ObserverSnapshot = rmp_serde::from_slice(&payload)
            .unwrap_or_else(|e| panic!("deserialization error at tick {}: {}", tick, e));

        last_snapshot = Some(snapshot);

        // Send empty input for next tick
        let empty: Vec<PlayerInput> = vec![];
        let input_payload = rmp_serde::to_vec(&empty).expect("serialize empty input");
        if write_framed(&mut writer, &input_payload).is_err() {
            // Server may have shut down after tick 10 — that's fine
            break;
        }
    }

    drop(reader);
    drop(writer);

    // Signal server thread that client is done reading
    barrier.wait();

    // Server thread must not have panicked
    server_handle.join().expect(
        "server thread panicked — content triggered a runtime error during tick processing",
    );

    // Validate final snapshot
    let snapshot = last_snapshot.expect("should have received at least one snapshot");
    assert_eq!(
        snapshot.version, PROTOCOL_VERSION,
        "snapshot protocol version mismatch"
    );
    // Content-spawned NPCs should be visible (they all spawn at 0,0,0 by default)
    // The player is at 16,16 — content NPCs are far away but the player entity itself
    // should always be in the snapshot
    assert!(
        !snapshot.entities.is_empty(),
        "snapshot should contain at least the player entity"
    );
}