#pragma semicolon 1
#include <sourcemod>
#include <sdktools>

new trigger[MAXPLAYERS+1] = 0;

public OnPluginStart() {

  HookEvent("player_spawn", player_spawn);
}

public Action:OnPlayerRunCmd(client, &buttons, &impulse, Float:vel[3], Float:angles[3], &weapon) {

  if (trigger[client] == 0) {
   if(GetClientButtons(client) & IN_DUCK) {
    CreateTimer(3.0, aTimer, client);
   }
  }
  if (trigger[client] == 1) {
   buttons &= ~IN_DUCK;  
   return Plugin_Changed;  
  }
  return Plugin_Continue;  
}

public player_spawn(Handle:event,const String:name[],bool:dontBroadcast) {

  new client = GetClientOfUserId(GetEventInt(event, "userid"));
  trigger[client] = 0;
}

public Action:aTimer(Handle:timer, any:client) {

  if (IsClientInGame(client)) trigger[client] = 1;
}