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// Globals

bool BootingB,    // Empty4 startup workaround in progress
     AutoScrollB; // To remember the chart's auto scroll setting as it is set to off while the Empty4 startup workaround is in progress

int EnoughBars;   // Bars sufficient for the indicator to run, allowing the Empty4 indicator booting problem workaround to exit

datetime InitTickT; // TST of the last tick at initialisation time

int OnInit() {
  ... anything which will not error on lack of account info or history can go here as usual e.g. buffer and indicator function calls.
  // Start of workaround
  BootingB  = true;
  InitTickT = TimeCurrent();
  EnoughBars = ... as requited by the indicator for the current period
  AutoScrollB = ChartGetInteger(0, CHART_AUTOSCROLL);
  if (AutoScrollB) ChartSetInteger(0, CHART_AUTOSCROLL, false); // turn off auto scroll if on
  if (EventSetTimer(1))
    Print("1 second timer started");
  else
    return InitError("EventSetTimer() failed"); // this will abort
  // Everything else is done in OwnInit() called from OnTimer() once the timer has determined that the history is ok
  return INIT_SUCCEEDED;
}

// bool OwnInit()
//      -------
// Initialisation function called from OnTimer() once Empty4 booting is complete
bool OwnInit() {
  // All the stuff which the indicator wants to do during initialisation which involves use of account info and history.
  ...
}

void OnTimer() {
  if (BootingB) {
    static int sPrevBars, sScrollsAtLastBarsChange, sScrolls, sNumNoConnection;
    if (!IsConnected()) {
      // Test for connectivity with comment to show what is happening rather than let the following code handle it with potentially a lot of log messages.
      // On the first time here on an Empty4 boot after closedown with the indi loaded the IsConnected() call gives false even when connected.
      Comment("Waiting for internet connection");
      return;
    }
    Comment("");
    PrintFormat("Empty4 indicator start workaround: Enough Bars %d, Acct# %d, Bars %d, Prev Bars %d, Scrolling %d", EnoughBars, AccountNumber(), Bars, sPrevBars, sScrolls);
    if (!AccountNumber() || Bars>sPrevBars || ((!EnoughBars || Bars<=EnoughBars) && (sScrolls-sScrollsAtLastBarsChange<3))) {
    //  Login not available (AccountNumber() serving as a check for all account info) || Bars still increasing || (not enough bars && scroll back attempt in progress)
      // Empty4 booting not complete yet
      if (AccountNumber() && Bars == sPrevBars) {
        // Login available and Bars have stopped increasing but EnoughBars haven't been reached or are still in a scroll back attempt, so scroll back in order to try to download more history
        ChartNavigate(0, CHART_BEGIN, -2000); // only does the number of bars visible on screen so this must be repeated
        sScrolls++;
      }else
        sScrollsAtLastBarsChange = sScrolls; // Used because it seemed that more than 1 second is needed to complete downloading a screen's worth of bars. 3 times was enough for all brokers I have tested this with.
      sPrevBars = Bars;
      return; // Empty4 booting not complete yet
    }
    // Empty4 booting appears to be complete
    BootingB = false;
    ChartSetInteger(0, CHART_AUTOSCROLL, AutoScrollB); // restore the auto scroll setting
    ChartNavigate(0, CHART_END, Bars); // navigate to the end of the chart
    if (!OwnInit()) return;
    if (TimeCurrent() == InitTickT) start(); // No tick has arrived since startup so call start() like Empty4 does for an indicator after running OnInit() to give weekend output
  }
  ... anything else to be done by the timer
}

void start() {
  if (BootingB) return; // Part of working around the Empty4 design fault of calling OnInit() for an indicator before history updating is complete or account information is available.
  ... rest of start() as usual
}