import { io, Socket } from 'socket.io-client';
import type { ServerEvents, ClientEvents, WorldState, StateUpdate, PlayerJoined, PlayerLeft, PlayerInput, SuperlativesData, NarrationEvent, MemoryEvent, InventionSummary, StockpileLogEntry } from '@dflike/shared';

type TypedSocket = Socket<ServerEvents, ClientEvents>;

export class SocketClient {
  private socket: TypedSocket;
  private _playerId: string | null = null;
  private _entityId: number | null = null;

  // Event callbacks
  onWorldState: ((data: WorldState) => void) | null = null;
  onStateUpdate: ((data: StateUpdate) => void) | null = null;
  onPlayerJoined: ((data: PlayerJoined) => void) | null = null;
  onPlayerLeft: ((data: PlayerLeft) => void) | null = null;
  onSuperlativesUpdate: ((data: SuperlativesData) => void) | null = null;
  onNarrationEvent: ((data: NarrationEvent) => void) | null = null;
  onNarrationUpdate: ((data: { id: number; narration: string }) => void) | null = null;
  onNarrationHistory: ((data: NarrationEvent[]) => void) | null = null;
  onNpcThought: ((data: { entityId: number; text: string; emoji: string }) => void) | null = null;
  onMemoryEvent: ((data: { entityId: number; event: MemoryEvent }) => void) | null = null;
  onMemoryHistory: ((data: { entityId: number; events: MemoryEvent[] }) => void) | null = null;
  onInventionEvent: ((data: InventionSummary) => void) | null = null;
  onInventionHistory: ((data: InventionSummary[]) => void) | null = null;
  onStockpileEvent: ((data: StockpileLogEntry) => void) | null = null;
  onStockpileHistory: ((data: StockpileLogEntry[]) => void) | null = null;
  onStockpileSummary: ((data: Record<string, number>) => void) | null = null;

  // Buffers for history events that may arrive before handlers are registered
  private _bufferedInventionHistory: InventionSummary[] | null = null;
  private _bufferedNarrationHistory: NarrationEvent[] | null = null;
  private _bufferedStockpileHistory: StockpileLogEntry[] | null = null;
  private _bufferedStockpileSummary: Record<string, number> | null = null;

  constructor(url: string) {
    this.socket = io(url);

    this.socket.on('world-state', (data) => {
      this.onWorldState?.(data);
    });

    this.socket.on('state-update', (data) => {
      this.onStateUpdate?.(data);
    });

    this.socket.on('player-joined', (data) => {
      if (!this._playerId) {
        this._playerId = data.playerId;
        this._entityId = data.entityId;
      }
      this.onPlayerJoined?.(data);
    });

    this.socket.on('player-left', (data) => {
      this.onPlayerLeft?.(data);
    });

    this.socket.on('superlatives-update', (data) => {
      this.onSuperlativesUpdate?.(data);
    });

    this.socket.on('narration-event', (data) => this.onNarrationEvent?.(data));
    this.socket.on('narration-update', (data) => this.onNarrationUpdate?.(data));
    this.socket.on('narration-history', (data) => {
      if (this.onNarrationHistory) this.onNarrationHistory(data);
      else this._bufferedNarrationHistory = data;
    });
    this.socket.on('npc-thought', (data) => this.onNpcThought?.(data));
    this.socket.on('memory-event', (data) => this.onMemoryEvent?.(data));
    this.socket.on('memory-history', (data) => this.onMemoryHistory?.(data));
    this.socket.on('invention-event', (data) => this.onInventionEvent?.(data));
    this.socket.on('invention-history', (data) => {
      if (this.onInventionHistory) this.onInventionHistory(data);
      else this._bufferedInventionHistory = data;
    });
    this.socket.on('stockpile-event', (data) => this.onStockpileEvent?.(data));
    this.socket.on('stockpile-history', (data) => {
      if (this.onStockpileHistory) this.onStockpileHistory(data);
      else this._bufferedStockpileHistory = data;
    });
    this.socket.on('stockpile-summary', (data) => {
      if (this.onStockpileSummary) this.onStockpileSummary(data);
      else this._bufferedStockpileSummary = data;
    });
  }

  get playerId(): string | null { return this._playerId; }
  get entityId(): number | null { return this._entityId; }

  /** Flush any history events that arrived before handlers were registered */
  flushBufferedHistory(): void {
    if (this._bufferedNarrationHistory && this.onNarrationHistory) {
      this.onNarrationHistory(this._bufferedNarrationHistory);
      this._bufferedNarrationHistory = null;
    }
    if (this._bufferedInventionHistory && this.onInventionHistory) {
      this.onInventionHistory(this._bufferedInventionHistory);
      this._bufferedInventionHistory = null;
    }
    if (this._bufferedStockpileHistory && this.onStockpileHistory) {
      this.onStockpileHistory(this._bufferedStockpileHistory);
      this._bufferedStockpileHistory = null;
    }
    if (this._bufferedStockpileSummary && this.onStockpileSummary) {
      this.onStockpileSummary(this._bufferedStockpileSummary);
      this._bufferedStockpileSummary = null;
    }
  }

  sendInput(input: PlayerInput): void {
    this.socket.emit('player-input', input);
  }

  spawnNpc(x: number, y: number): void {
    this.socket.emit('spawn-npc', { x, y });
  }

  followNpc(entityId: number | null): void {
    this.socket.emit('follow-npc', { entityId });
  }


  subscribeSuperlatives(): void {
    this.socket.emit('superlatives-subscribe');
  }

  unsubscribeSuperlatives(): void {
    this.socket.emit('superlatives-unsubscribe');
  }

  disconnect(): void {
    this.socket.disconnect();
  }
}