import { Server, Socket } from 'socket.io';
import type http from 'http';
import type { ClientEvents, ServerEvents, PlayerInput, Position, Movement, PlayerControlled, Appearance, EntityId } from '@dflike/shared';
import { Direction } from '@dflike/shared';
import { generateRandomAppearance } from '../spawner/appearanceGenerator.js';
import type { GameLoop } from '../game/GameLoop.js';
import { spawnNPC } from '../game/spawner.js';
import { serializeWorldState, serializeStateUpdate } from './stateSerializer.js';
import { computeSuperlatives } from '../systems/superlativesComputer.js';
import type { BondRegistry } from '../systems/bondRegistry.js';
import type { InventionTimeline } from '../industry/inventionTimeline.js';
import type { StockpileLog } from '../industry/stockpileLog.js';
import type { StructureData } from '../systems/buildingSystem.js';

export class SocketServer {
  private io: Server<ClientEvents, ServerEvents>;
  private gameLoop: GameLoop;
  private superlativesSubscribers: Set<Socket<ClientEvents, ServerEvents>> = new Set();
  private superlativesTimer: ReturnType<typeof setInterval> | null = null;
  private followedEntities: Map<string, EntityId | null> = new Map();
  private logSubscribers: Map<string, () => void> = new Map();
  private authenticatedSockets: Set<string> = new Set();

  constructor(httpServer: http.Server, gameLoop: GameLoop) {
    this.io = new Server(httpServer, {
      cors: { origin: '*' },
    });
    this.gameLoop = gameLoop;

    this.setupBroadcast();
    this.setupConnections();
  }

  private setupBroadcast(): void {
    this.gameLoop.setBroadcastHandler(() => {
      const update = serializeStateUpdate(this.gameLoop.world, this.gameLoop.map, this.gameLoop.getTick(), this.gameLoop.getGameTime(), this.gameLoop.getDayNumber());
      this.io.emit('state-update', update);
    });

    const narrationService = this.gameLoop.narrationService;

    narrationService.onEventCreated = (event) => {
      this.io.emit('narration-event', event);
    };

    narrationService.onEventUpdated = (event) => {
      this.io.emit('narration-update', { id: event.id, narration: event.narration });
    };

    this.gameLoop.thoughtSystem.onThought = (data) => {
      this.io.emit('npc-thought', data);
    };

    this.gameLoop.onInventionCreated = (summary) => {
      this.io.emit('invention-event', summary);
    };

    this.gameLoop.onStockpileEvent = (entry) => {
      this.io.emit('stockpile-event', entry);
      this.io.emit('stockpile-summary', this.computeStockpileSummary());
    };

    this.gameLoop.eventMemoryService.onEventRecorded = (entityId, event) => {
      // Only send to clients following this NPC
      for (const [socketId, followedId] of this.followedEntities) {
        if (followedId === entityId) {
          const sock = this.io.sockets.sockets.get(socketId);
          sock?.emit('memory-event', { entityId, event });
        }
      }
    };
  }

  private setupConnections(): void {
    this.io.on('connection', (socket) => {
      const playerId = socket.id;
      console.log(`Player connected: ${playerId}`);
      this.gameLoop.logService.log('info', 'Network', `Player connected: ${playerId}`);

      // Create player entity (starts in camera mode — no avatar)
      const world = this.gameLoop.world;
      const map = this.gameLoop.map;
      const entity = world.createEntity();
      const startPos = map.getRandomWalkable();
      world.addComponent<Position>(entity, 'position', startPos);
      world.addComponent<Movement>(entity, 'movement', {
        state: 'idle', target: null, path: [], direction: Direction.DOWN, moveProgress: 0,
      });
      world.addComponent<PlayerControlled>(entity, 'playerControlled', {
        playerId, mode: 'camera',
      });
      world.addComponent<Appearance>(entity, 'appearance', generateRandomAppearance());

      // Send full world state
      socket.emit('world-state', serializeWorldState(world, map));
      socket.emit('player-joined', { playerId, entityId: entity });

      // Send narration history
      socket.emit('narration-history', this.gameLoop.narrationService.getRecentEvents());

      // Send invention history
      const inventionTimeline = this.gameLoop.world.getSingleton<InventionTimeline>('inventionTimeline');
      if (inventionTimeline) {
        socket.emit('invention-history', inventionTimeline.getSummaries());
      }

      // Send stockpile history and summary
      const stockpileLog = this.gameLoop.world.getSingleton<StockpileLog>('stockpileLog');
      if (stockpileLog) {
        socket.emit('stockpile-history', stockpileLog.getRecent());
      }
      socket.emit('stockpile-summary', this.computeStockpileSummary());

      // Notify others
      socket.broadcast.emit('player-joined', { playerId, entityId: entity });

      // Handle inputs
      socket.on('player-input', (input: PlayerInput) => {
        this.handleInput(playerId, entity, input);
      });

      // Handle NPC spawn requests
      socket.on('spawn-npc', (data: { x: number; y: number }) => {
        const npcCount = world.query('npcBrain').length;
        if (npcCount >= this.gameLoop.runtimeConstants.get('MAX_NPC_COUNT')) return;

        const target = map.findNearestWalkable(data.x, data.y, 3)
          ?? map.getRandomWalkable();
        const npcEntity = spawnNPC(world, map, target, this.gameLoop.eventMemoryService);
        this.gameLoop.generateNpcBackstory(npcEntity);
      });

      // Handle superlatives subscription
      socket.on('superlatives-subscribe', () => {
        this.superlativesSubscribers.add(socket);
        // Send immediately
        const registry = this.gameLoop.world.getSingleton<BondRegistry>('bondRegistry');
        if (registry) {
          const inventionTimeline = this.gameLoop.world.getSingleton<InventionTimeline>('inventionTimeline');
          const data = computeSuperlatives(this.gameLoop.world, registry, inventionTimeline);
          socket.emit('superlatives-update', data);
        }
        // Start timer if first subscriber
        if (!this.superlativesTimer && this.superlativesSubscribers.size === 1) {
          this.superlativesTimer = setInterval(() => {
            this.broadcastSuperlatives();
          }, 10000);
        }
      });

      socket.on('superlatives-unsubscribe', () => {
        this.superlativesSubscribers.delete(socket);
        this.stopSuperlativesTimerIfEmpty();
      });

      // Handle follow-npc
      socket.on('follow-npc', (data: { entityId: EntityId | null }) => {
        this.followedEntities.set(socket.id, data.entityId);
        this.rebuildFollowedEntityIds();

        // Send memory history when following a new NPC
        if (data.entityId !== null) {
          const events = this.gameLoop.eventMemoryService.getEvents(data.entityId);
          if (events.length > 0) {
            socket.emit('memory-history', { entityId: data.entityId, events });
          }
        }
      });

      // Admin authentication
      const ADMIN_PASSWORD = 'dwarf';

      socket.on('admin-auth', (data: { password: string }) => {
        if (data.password === ADMIN_PASSWORD) {
          this.authenticatedSockets.add(socket.id);
          socket.emit('admin-auth-result', {
            success: true,
            constants: this.gameLoop.runtimeConstants.getAll(),
          });
        } else {
          socket.emit('admin-auth-result', { success: false });
        }
      });

      socket.on('admin-update-constant', (data: { key: any; value: number }) => {
        if (!this.authenticatedSockets.has(socket.id)) return;
        const success = this.gameLoop.runtimeConstants.update(data.key, data.value);
        if (success) {
          this.io.emit('admin-constants-updated', this.gameLoop.runtimeConstants.getAll());
          this.gameLoop.logService.log('info', 'Game', `Admin updated ${data.key} to ${data.value}`);
        }
      });

      socket.on('admin-reset-defaults', () => {
        if (!this.authenticatedSockets.has(socket.id)) return;
        this.gameLoop.runtimeConstants.resetDefaults();
        this.io.emit('admin-constants-updated', this.gameLoop.runtimeConstants.getAll());
        this.gameLoop.logService.log('info', 'Game', 'Admin reset all constants to defaults');
      });

      socket.on('admin-llm-stats', () => {
        if (!this.authenticatedSockets.has(socket.id)) return;
        const stats = this.gameLoop.llmStatsService.getStats();
        socket.emit('admin-llm-stats-result', stats);
      });

      socket.on('admin-reset-llm-stats', () => {
        if (!this.authenticatedSockets.has(socket.id)) return;
        this.gameLoop.llmStatsService.resetStats();
        const stats = this.gameLoop.llmStatsService.getStats();
        socket.emit('admin-llm-stats-result', stats);
        this.gameLoop.logService.log('info', 'Game', 'Admin reset LLM stats');
      });

      socket.on('admin-toggle-llm-tracking', (data: { enabled: boolean }) => {
        if (!this.authenticatedSockets.has(socket.id)) return;
        this.gameLoop.llmStatsService.setTrackingEnabled(data.enabled);
        this.io.emit('admin-llm-tracking-toggled', { enabled: data.enabled });
        this.gameLoop.logService.log('info', 'Game', `Admin ${data.enabled ? 'enabled' : 'disabled'} LLM tracking`);
      });

      // Log streaming
      socket.on('log-subscribe', () => {
        // Send history first
        socket.emit('log-history', this.gameLoop.logService.getRecent());
        // Subscribe to new entries
        const unsub = this.gameLoop.logService.subscribe((entry) => {
          socket.emit('log-entry', entry);
        });
        this.logSubscribers.set(socket.id, unsub);
      });

      socket.on('log-unsubscribe', () => {
        const unsub = this.logSubscribers.get(socket.id);
        if (unsub) {
          unsub();
          this.logSubscribers.delete(socket.id);
        }
      });

      // Handle disconnect
      socket.on('disconnect', () => {
        console.log(`Player disconnected: ${playerId}`);
        this.gameLoop.logService.log('info', 'Network', `Player disconnected: ${playerId}`);
        this.authenticatedSockets.delete(socket.id);
        this.superlativesSubscribers.delete(socket);
        this.stopSuperlativesTimerIfEmpty();
        this.followedEntities.delete(socket.id);
        this.rebuildFollowedEntityIds();
        const logUnsub = this.logSubscribers.get(socket.id);
        if (logUnsub) {
          logUnsub();
          this.logSubscribers.delete(socket.id);
        }
        world.removeEntity(entity);
        this.io.emit('player-left', { playerId });
      });
    });
  }

  private computeStockpileSummary(): Record<string, number> {
    const summary: Record<string, number> = {};
    for (const entity of this.gameLoop.world.query('structure')) {
      const s = this.gameLoop.world.getComponent<StructureData>(entity, 'structure')!;
      if (s.type !== 'stockpile' || s.buildProgress !== undefined) continue;
      for (const [itemId, qty] of s.inventory) {
        summary[itemId] = (summary[itemId] ?? 0) + qty;
      }
    }
    return summary;
  }

  private broadcastSuperlatives(): void {
    if (this.superlativesSubscribers.size === 0) return;
    const registry = this.gameLoop.world.getSingleton<BondRegistry>('bondRegistry');
    if (!registry) return;
    const inventionTimeline = this.gameLoop.world.getSingleton<InventionTimeline>('inventionTimeline');
    const data = computeSuperlatives(this.gameLoop.world, registry, inventionTimeline);
    for (const socket of this.superlativesSubscribers) {
      socket.emit('superlatives-update', data);
    }
  }

  private stopSuperlativesTimerIfEmpty(): void {
    if (this.superlativesSubscribers.size === 0 && this.superlativesTimer) {
      clearInterval(this.superlativesTimer);
      this.superlativesTimer = null;
    }
  }

  private rebuildFollowedEntityIds(): void {
    this.gameLoop.followedEntityIds.clear();
    for (const [, entityId] of this.followedEntities) {
      if (entityId !== null) this.gameLoop.followedEntityIds.add(entityId);
    }
  }

  private handleInput(playerId: string, entityId: number, input: PlayerInput): void {
    const world = this.gameLoop.world;
    const pc = world.getComponent<PlayerControlled>(entityId, 'playerControlled');
    if (!pc) return;

    switch (input.type) {
      case 'toggle-mode': {
        pc.mode = pc.mode === 'avatar' ? 'camera' : 'avatar';
        break;
      }
      case 'move': {
        if (pc.mode !== 'avatar' || !input.direction) break;
        const pos = world.getComponent<Position>(entityId, 'position');
        const mov = world.getComponent<Movement>(entityId, 'movement');
        if (!pos || !mov) break;

        const newX = pos.x + input.direction.dx;
        const newY = pos.y + input.direction.dy;
        if (this.gameLoop.map.isWalkable(newX, newY)) {
          pos.x = newX;
          pos.y = newY;

          const { dx, dy } = input.direction;
          if (Math.abs(dx) > Math.abs(dy)) {
            mov.direction = dx > 0 ? Direction.RIGHT : Direction.LEFT;
          } else {
            mov.direction = dy > 0 ? Direction.DOWN : Direction.UP;
          }
        }
        break;
      }
    }
  }
}