//! Shared fixtures for the tavolo-platform test suite.
//!
//! `DummyEngine` is a tiny two-player game implementing the platform's
//! `GameEngine` contract, so every platform behaviour (lobby, store,
//! websockets, deadlines, stats) is exercised without importing any real
//! game. Its rules: the first player to reach `target` plays wins.

#![allow(dead_code)]

use std::sync::Arc;

use axum::body::Body;
use axum::http::{Request, Response, StatusCode};
use axum::Router;
use futures_util::StreamExt;
use serde_json::{json, Map, Value};
use tower::ServiceExt;

use tavolo_platform::deadlines::DeadlineScheduler;
use tavolo_platform::engine::{Deadline, GameEngine, GameSession, MatchResult, PlayerResult, Seat};
use tavolo_platform::errors::{Error, GameError, Result};
use tavolo_platform::oidc::{OidcProviderConfig, OidcProviders};
use tavolo_platform::platform::{Platform, SharedPlatform};
use tavolo_platform::registry::GameRegistry;
use tavolo_platform::session::{session_middleware, InMemorySessionStore, SharedSessionStore};
use tavolo_platform::stats::{InMemoryStatsRepo, SharedStatsRepo};
use tavolo_platform::store::{InMemoryGameStore, SharedGameStore};

#[derive(Clone, Debug, serde::Serialize, serde::Deserialize)]
pub struct DummyState {
    pub target: i64,
    pub plays: Vec<String>,
    pub started: bool,
    pub finished: bool,
    pub winner: Option<String>,
    pub deadline_in_seconds: Option<f64>,
}

pub struct DummyEngine;

fn state_of(session: &GameSession) -> Result<&DummyState> {
    session
        .state
        .as_ref()
        .and_then(|state| state.downcast_ref::<DummyState>())
        .ok_or_else(|| Error::Internal("dummy state missing".into()))
}

fn state_of_mut(session: &mut GameSession) -> Result<&mut DummyState> {
    session
        .state
        .as_mut()
        .and_then(|state| state.downcast_mut::<DummyState>())
        .ok_or_else(|| Error::Internal("dummy state missing".into()))
}

impl DummyEngine {
    fn play(session: &mut GameSession, user_sub: &str) -> Result<()> {
        let state = state_of_mut(session)?;
        state.plays.push(user_sub.to_string());
        if state.plays.len() as i64 >= state.target {
            state.finished = true;
            state.winner = Some(user_sub.to_string());
        }
        Ok(())
    }
}

impl GameEngine for DummyEngine {
    fn id(&self) -> &'static str {
        "dummy"
    }

    fn name(&self) -> &'static str {
        "Dummy game"
    }

    fn description(&self) -> &'static str {
        "A two-player toy game for testing the platform."
    }

    fn min_players(&self) -> usize {
        2
    }

    fn max_players(&self) -> usize {
        2
    }

    fn options_schema(&self) -> Value {
        json!({
            "type": "object",
            "properties": {
                "target": {
                    "type": "integer",
                    "minimum": 1,
                    "default": 3,
                    "description": "Plays needed to win the match.",
                },
                "deadline_in_seconds": {
                    "type": "number",
                    "description": "Arm a tick deadline this far in the future.",
                },
            },
        })
    }

    fn create(&self, session: &mut GameSession, options: &Map<String, Value>) -> Result<()> {
        let target = options.get("target").and_then(Value::as_i64).unwrap_or(3);
        if target < 1 || options.get("target").is_some_and(|v| v.is_boolean()) {
            return Err(GameError::illegal_move("target must be a positive integer").into());
        }
        let creator = session.players[0].clone();
        session.players[0] = Seat {
            user_sub: creator.user_sub,
            display_name: creator.display_name,
            team: Some("A".into()),
        };
        session.state = Some(Box::new(DummyState {
            target,
            plays: Vec::new(),
            started: false,
            finished: false,
            winner: None,
            deadline_in_seconds: options.get("deadline_in_seconds").and_then(Value::as_f64),
        }));
        Ok(())
    }

    fn join(&self, session: &mut GameSession, user_sub: &str, display_name: &str) -> Result<()> {
        if state_of(session)?.started {
            return Err(GameError::game_not_started("game has already started").into());
        }
        if session.seated(user_sub) {
            return Err(GameError::already_joined("already joined this game").into());
        }
        if session.players.len() >= 2 {
            return Err(GameError::lobby_full("game is full").into());
        }
        let team = if session.players.is_empty() { "A" } else { "B" };
        session.players.push(Seat {
            user_sub: user_sub.into(),
            display_name: display_name.into(),
            team: Some(team.into()),
        });
        if session.players.len() == 2 {
            state_of_mut(session)?.started = true;
        }
        Ok(())
    }

    fn handle_action(
        &self,
        session: &mut GameSession,
        user_sub: &str,
        action: &str,
        _payload: &Map<String, Value>,
    ) -> Result<()> {
        if !state_of(session)?.started {
            return Err(GameError::game_not_started("the game has not started yet").into());
        }
        if state_of(session)?.finished {
            return Err(GameError::game_finished("the match is over").into());
        }
        if !session.seated(user_sub) {
            return Err(GameError::not_your_turn("you are not seated in this game").into());
        }
        if action != "play" {
            return Err(GameError::illegal_move(format!(
                "unknown action: {}",
                tavolo_platform::http::py_repr(&Value::String(action.to_string()))
            ))
            .into());
        }
        DummyEngine::play(session, user_sub)
    }

    fn view_for(&self, session: &GameSession, user_sub: &str) -> Value {
        let state = state_of(session).expect("dummy state");
        json!({
            "started": state.started,
            "finished": state.finished,
            "winner": state.winner,
            "plays": state.plays.len(),
            "target": state.target,
            "viewer_seated": session.seated(user_sub),
        })
    }

    fn lobby_view(&self, session: &GameSession) -> Value {
        let state = state_of(session).expect("dummy state");
        json!({
            "phase": if state.started { "playing" } else { "lobby" },
            "target": state.target,
        })
    }

    fn in_lobby(&self, session: &GameSession) -> bool {
        state_of(session)
            .map(|state| !state.started)
            .unwrap_or(false)
    }

    fn is_finished(&self, session: &GameSession) -> bool {
        state_of(session)
            .map(|state| state.finished)
            .unwrap_or(false)
    }

    fn result(&self, session: &GameSession) -> Result<MatchResult> {
        let state = state_of(session)?;
        let Some(winner) = state.winner.clone() else {
            return Err(GameError::illegal_move("no result: the match is not finished").into());
        };
        let subs: Vec<String> = session
            .players
            .iter()
            .map(|seat| seat.user_sub.clone())
            .collect();
        Ok(MatchResult {
            teams: vec![vec![subs[0].clone()], vec![subs[1].clone()]],
            winner_team: subs.iter().position(|sub| *sub == winner).unwrap_or(0),
            players: session
                .players
                .iter()
                .enumerate()
                .map(|(index, seat)| PlayerResult {
                    user_sub: seat.user_sub.clone(),
                    seat: index as i64,
                    won: seat.user_sub == winner,
                    team: seat.team.clone(),
                    score: state
                        .plays
                        .iter()
                        .filter(|sub| **sub == seat.user_sub)
                        .count() as f64,
                    details: json!({
                        "plays": state.plays.iter().filter(|sub| **sub == seat.user_sub).count(),
                    }),
                })
                .collect(),
            summary: json!({
                "target": state.target,
                "plays": state.plays.len(),
                "winner": winner,
            }),
        })
    }

    fn state_to_json(&self, state: &(dyn std::any::Any + Send + Sync)) -> Result<Value> {
        let state = state
            .downcast_ref::<DummyState>()
            .ok_or_else(|| Error::Internal("dummy state missing".into()))?;
        Ok(serde_json::to_value(state)?)
    }

    fn state_from_json(&self, data: &Value) -> Result<Box<dyn std::any::Any + Send + Sync>> {
        Ok(Box::new(serde_json::from_value::<DummyState>(
            data.clone(),
        )?))
    }

    fn next_deadline(&self, session: &GameSession) -> Result<Option<Deadline>> {
        let state = state_of(session)?;
        let Some(seconds) = state.deadline_in_seconds else {
            return Ok(None);
        };
        if !state.started || state.finished {
            return Ok(None);
        }
        let due_at = tavolo_platform::datetime::now()
            + chrono::Duration::milliseconds((seconds * 1000.0) as i64);
        Ok(Some(Deadline {
            kind: "tick".into(),
            due_at,
            token: format!("tick:{}", state.plays.len()),
        }))
    }

    fn fire_deadline(&self, session: &mut GameSession, kind: &str, token: &str) -> Result<()> {
        let current = self.next_deadline(session)?;
        match current {
            Some(current) if current.kind == kind && current.token == token => {}
            _ => return Err(GameError::illegal_move("stale deadline").into()),
        }
        let user_sub = session.players[0].user_sub.clone();
        DummyEngine::play(session, &user_sub)
    }
}

fn test_oidc_config(provider: &str) -> OidcProviderConfig {
    OidcProviderConfig {
        provider: provider.into(),
        issuer: format!("http://localhost:8180/{provider}"),
        client_id: "tavolo".into(),
        client_secret: None,
        redirect_uri: format!("http://localhost:8080/auth/{provider}/callback"),
        post_login_redirect: "/".into(),
        post_logout_redirect: "/".into(),
    }
}

pub struct TestPlatform {
    pub platform: SharedPlatform,
    pub session_store: SharedSessionStore,
    pub stats: Arc<InMemoryStatsRepo>,
}

impl TestPlatform {
    pub fn router(&self) -> Router {
        Router::new()
            .merge(
                tavolo_platform::routes::router(&["default".to_string()])
                    .with_state(self.platform.clone()),
            )
            .layer(axum::middleware::from_fn_with_state(
                self.session_store.clone(),
                session_middleware,
            ))
    }
}

pub fn make_platform(heartbeat_ms: u64) -> TestPlatform {
    let mut registry = GameRegistry::new();
    registry
        .register(Arc::new(DummyEngine))
        .expect("register dummy");
    let registry = Arc::new(registry);
    let game_store: SharedGameStore = Arc::new(InMemoryGameStore::new(registry.clone()));
    let session_store: SharedSessionStore = Arc::new(InMemorySessionStore::new());
    let stats = Arc::new(InMemoryStatsRepo::new());
    let stats_repo: SharedStatsRepo = stats.clone();
    let oidc =
        Arc::new(OidcProviders::new(vec![test_oidc_config("default")]).expect("oidc providers"));
    let scheduler = DeadlineScheduler::new(
        game_store.clone(),
        registry.clone(),
        stats_repo.clone(),
        heartbeat_ms,
        20,
    );
    scheduler.start();
    let platform = Arc::new(Platform {
        registry,
        game_store,
        scheduler,
        oidc,
        stats: stats_repo,
    });
    TestPlatform {
        platform,
        session_store,
        stats,
    }
}

/// Persist a logged-in session and return the `Cookie` header value for it.
pub async fn login_cookie(
    store: &SharedSessionStore,
    provider: &str,
    sub: &str,
    name: &str,
) -> String {
    let id = format!("session-{sub}");
    let mut data = Map::new();
    data.insert(
        format!("oidc:{provider}:user"),
        json!({"sub": sub, "preferred_username": name}),
    );
    store
        .save(&id, &data, Some(3600))
        .await
        .expect("save session");
    format!("session_id={id}")
}

pub async fn call(router: &Router, request: Request<Body>) -> Response<axum::body::Body> {
    router.clone().oneshot(request).await.expect("request")
}

pub async fn body_json(response: Response<Body>) -> Value {
    let bytes = axum::body::to_bytes(response.into_body(), usize::MAX)
        .await
        .expect("body");
    serde_json::from_slice(&bytes).expect("json body")
}

pub fn get(uri: &str, cookie: Option<&str>) -> Request<Body> {
    let mut builder = Request::builder().method("GET").uri(uri);
    if let Some(cookie) = cookie {
        builder = builder.header("cookie", cookie);
    }
    builder.body(Body::empty()).expect("request")
}

pub fn post_json(uri: &str, cookie: Option<&str>, body: &Value) -> Request<Body> {
    let mut builder = Request::builder()
        .method("POST")
        .uri(uri)
        .header("content-type", "application/json");
    if let Some(cookie) = cookie {
        builder = builder.header("cookie", cookie);
    }
    builder
        .body(Body::from(serde_json::to_vec(body).expect("json")))
        .expect("request")
}

pub async fn read_text(
    mut socket: tokio_tungstenite::WebSocketStream<
        tokio_tungstenite::MaybeTlsStream<tokio::net::TcpStream>,
    >,
) -> String {
    let message = socket
        .next()
        .await
        .expect("some message")
        .expect("ok message");
    match message {
        tokio_tungstenite::tungstenite::Message::Text(text) => text.to_string(),
        other => panic!("expected text message, got {other:?}"),
    }
}

pub async fn read_json(
    socket: &mut tokio_tungstenite::WebSocketStream<
        tokio_tungstenite::MaybeTlsStream<tokio::net::TcpStream>,
    >,
) -> Value {
    let message = socket
        .next()
        .await
        .expect("some message")
        .expect("ok message");
    match message {
        tokio_tungstenite::tungstenite::Message::Text(text) => {
            serde_json::from_str(&text).expect("json message")
        }
        other => panic!("expected text message, got {other:?}"),
    }
}

pub fn ws_request(addr: std::net::SocketAddr, game_id: &str, cookie: Option<&str>) -> Request<()> {
    use tokio_tungstenite::tungstenite::client::IntoClientRequest;
    let url = format!("ws://{addr}/ws/games/{game_id}");
    let mut request = url.into_client_request().expect("websocket client request");
    if let Some(cookie) = cookie {
        request.headers_mut().insert(
            "cookie",
            axum::http::HeaderValue::from_str(cookie).expect("cookie header"),
        );
    }
    request
}

pub async fn start_server(router: Router) -> std::net::SocketAddr {
    let listener = tokio::net::TcpListener::bind("127.0.0.1:0")
        .await
        .expect("bind");
    let addr = listener.local_addr().expect("addr");
    tokio::spawn(async move {
        let _ = axum::serve(listener, router).await;
    });
    addr
}

pub fn json_status(response: &Response<Body>) -> StatusCode {
    response.status()
}