node-haxball/examples/plugins/CMD_shareFiles.js

The most powerful and lightweight API that allows you to develop your original Haxball(www.haxball.com) host, client, and standalone applications both on node.js and browser environments and also includes every possible hack and functionality that you can

module.exports = function (API) {
  const { OperationType, VariableType, ConnectionState, AllowFlags, Direction, CollisionFlags, CameraFollow, BackgroundType, GamePlayState, BanEntryType, Callback, Utils, Room, Replay, Query, Library, RoomConfig, Plugin, Renderer, Errors, Language, EventFactory, Impl } = API;
  Object.setPrototypeOf(this, Plugin.prototype);
  Plugin.call(this, "CMD_shareFiles", false, { // "CMD_shareFiles" is plugin's name, "true" means "activated just after initialization". Every plugin should have a unique name.
    version: "0.1",
    author: "abc",
    description: "This plugin allows us to send files to other players.",
    allowFlags: AllowFlags.CreateRoom // We allow this plugin to be activated on CreateRoom only.
  });

  this.defineVariable({
    name: "playerIdToSend",
    description: "Id of the player who will receive the data.",
    type: VariableType.PlayerId,
    value: 1
  });

  this.defineVariable({
    name: "dataToSend",
    description: "Data to send.",
    type: VariableType.File
  });

  this.defineVariable({
    name: "send",
    description: "Sends a file to the selected player.",
    type: VariableType.Void,
    value: ()=>{
      if (!fsEnabled[that.playerIdToSend] || !that.dataToSend)
        return;
      var {name, size} = that.dataToSend;
      if (size>10*1024*1024){
        console.warn("blocked attempt to send a file (size > 10mb)");
        return;
      }
      const reader = new FileReader();
      reader.addEventListener("load", (e) => {
        that.room.librariesMap.userInteractions?.activateInteraction(that.playerIdToSend, fileInteraction, {
          targetId: that.playerIdToSend,
          byId: 0,
          name: name,
          contents: e.target.result
        });
      });
      reader.readAsArrayBuffer(that.dataToSend);
    }
  });

  function meaningfulSize(byteLength){
    const v = (1<<10)-1, gb = (byteLength&(v<<30))>>30, mb = (byteLength&(v<<20))>>20, kb = (byteLength&(v<<10))>>10, b = byteLength&v, str = [];
    gb>0 && str.push(gb+" gb");
    mb>0 && str.push(mb+" mb");
    kb>0 && str.push(kb+" kb");
    b>0 && str.push(b+" bytes");
    return str.join(" + ");
  }

  var that = this, fileInteraction = null, fsEnabled = null;

  this.initialize = function(){
    that.room.librariesMap.commands?.add({
      name: "fs_answer",
      parameters: [{
        name: "answer",
        type: VariableType.String,
        range: {
          min: 1,
          max: 1
        }
      }],
      minParameterCount: 1,
      helpText: "Accept or reject a file.",
      callback: ({answer}, byId) => {
        if (answer=="y")
          answer=true;
        else if (answer=="n")
          answer=false;
        else
          return;
        that.room.librariesMap.userInteractions?.onInput(byId, answer, byId);
      }
    });
    that.room.librariesMap.commands?.add({
      name: "fs_allow",
      parameters: [{
        name: "value",
        type: VariableType.Boolean
      }],
      minParameterCount: 1,
      helpText: "Enables or disables file sharing.",
      callback: ({value}, byId) => {
        fsEnabled[byId] = value;
      }
    });
    fileInteraction = that.room.librariesMap.userInteractions?.createYesNoChatInteraction(({playerId, data})=>{
      return (that.room.getPlayer(data.byId)?.name || "")+" ["+data.byId+"]"+" is trying to send a file (name='"+data.name+"', size="+meaningfulSize(data.contents.byteLength)+") to you. Do you accept it? (Answer with !fs_answer [y|n])";
    }, (playerId, {targetId, byId, name, contents})=>{
      if (targetId==0)
        that.room.librariesMap.gui?.downloadFile(name, contents);
      else{
        var writer = Impl.Stream.Writer.create(name.length+contents.byteLength+8, true);
        writer.writeInt32(byId);
        writer.writeString(name);
        writer.writeArrayBuffer(contents);
        that.room.sendBinaryCustomEvent(0, writer.toUint8Array(), targetId);
      }
    }, (playerId, data)=>{
      console.log("Rejected");
    });
    fsEnabled = {};
  };

  this.finalize = function(){
    that.room.librariesMap.commands?.remove("fs_answer");
    fileInteraction = null;
    fsEnabled = null;
  };

  this.onPlayerLeave = function(playerObj, reason, isBanned, byId, customData){
    delete fsEnabled[playerObj.id];
  };

  this.onOperationReceived = function(type, msg){
    if (type!=OperationType.BinaryCustomEvent)
      return true;
    var {type, data, byId} = msg;
    if (type!=1 || byId==0)
      return true;
    var b = new Impl.Stream.Reader(new DataView(data.buffer, data.byteOffset, data.byteLength), true), targetId = b.readInt32();
    if (!fsEnabled[targetId] || !that.room.getPlayer(targetId))
      return false;
    var name = b.readString(), contents = b.readUint8Array();
    that.room.librariesMap.userInteractions?.activateInteraction(targetId, fileInteraction, {
      targetId,
      byId,
      name,
      contents
    });
  };
}