// ---------------------------------------------------------------------------
// Network protocol shared between server and client (JSON over WebSocket)
// ---------------------------------------------------------------------------

export interface PelletData {
  id: number;
  x: number;
  y: number;
  v: number;  // food value (also drives render size)
  c: number;  // color index into PELLET_COLORS
}

export interface SnakeSnap {
  id: number;
  n: string;        // nickname
  c: number;        // color index into SNAKE_COLORS
  s: number;        // score
  p: number[];      // flat body points [x0,y0,x1,y1,...], head first
  b: boolean;       // boosting
  k: number;        // kills
  sp?: boolean;     // spawn protection active (ghost)
}

export type GameEvent =
  | { t: 'die'; id: number; x: number; y: number; c: number; s: number; p: number[] }
  | { t: 'join'; id: number; n: string }
  | { t: 'leave'; id: number };

export interface LeaderboardRow {
  id: number;
  n: string;
  s: number;
}

export interface YouState {
  score: number;
  rank: number;
  alive: boolean;
  kills: number;
  best: number;
}

// --- server -> client -------------------------------------------------------

export interface InitMsg {
  t: 'init';
  id: number;          // your snake id
  arena: number;       // arena radius
  pellets: PelletData[]; // full pellet list (deltas arrive afterwards)
}

export interface SnapMsg {
  t: 'snap';
  tick: number;
  snakes: SnakeSnap[];
  add: PelletData[];   // pellets added since last snapshot
  rem: number[];       // pellet ids removed since last snapshot
  ev: GameEvent[];     // events since last snapshot
  lb: LeaderboardRow[];
  you?: YouState;
  total: number;       // total snakes alive
}

export type ServerMsg = InitMsg | SnapMsg;

// --- client -> server -------------------------------------------------------

export interface JoinMsg { t: 'join'; name: string }
export interface InputMsg { t: 'in'; a: number; b: boolean } // angle, boosting
export interface RespawnMsg { t: 'respawn' }

export type ClientMsg = JoinMsg | InputMsg | RespawnMsg;