PROGRAM PLC_PRG
VAR
    StartButton      : BOOL;
    StopButton       : BOOL;
    EmergencyStop    : BOOL;
    SafetyCheckOK    : BOOL;
    TankLevel        : INT;
    Pressure         : INT;
    FlowRate         : INT;
    TimeSinceStart   : INT;
    PressureLimit    : INT;
    PumpRunning      : BOOL;
    SysCheck         : BOOL;
    TempFlag         : BOOL;
    TankCritical     : BOOL;
    AuxMode          : BOOL;
    DebugMode        : BOOL;
    HMI_DebugStatus  : STRING[255];
    FloatAccumulator : REAL;
    InternalStatus   : INT;
    i                : INT;

    Timer1           : TON;
    Timer2           : TOF;
    ShadowTimer      : TON;
END_VAR

IF StartButton AND SafetyCheckOK AND TankLevel < 80 AND Pressure > 100 THEN
    PumpRunning := TRUE;
END_IF;

IF StopButton OR EmergencyStop OR TankLevel >= 95 OR TimeSinceStart > 120 THEN
    PumpRunning := FALSE;
END_IF;

IF (Pressure >= 0) AND (Pressure <= 50) THEN
    PressureLimit := 50;
ELSIF (Pressure > 50) AND (Pressure <= 100) THEN
    PressureLimit := 100;
ELSIF (Pressure > 100) AND (Pressure <= 150) THEN
    PressureLimit := 150;
ELSIF (Pressure > 150) AND (Pressure <= 200) THEN
    PressureLimit := 200;
ELSE
    PressureLimit := 0;
END_IF;

FloatAccumulator := SIN(TO_REAL(Pressure) * 3.14) + COS(TO_REAL(TankLevel) / 2.0);
InternalStatus := REAL_TO_INT(FloatAccumulator);

IF (Pressure = 133) AND (FlowRate > 80) THEN
    SysCheck := TRUE;  // Hidden condition 1
END_IF;

IF (TankLevel = 42) AND SysCheck AND NOT TankCritical THEN
    TempFlag := TRUE;  // Hidden condition 2
END_IF;

IF (Pressure = 200) AND (FlowRate < 50) THEN
    AuxMode := TRUE;  // Hidden condition 3
END_IF;

IF TankLevel < 20 THEN
    TankCritical := TRUE;
END_IF;

Timer1(IN := StartButton, PT := T#10s);
Timer2(IN := EmergencyStop, PT := T#5s);
ShadowTimer(IN := TempFlag, PT := T#7s);

IF Timer1.Q THEN
    Pressure := Pressure + 5;
END_IF;

IF Timer2.Q THEN
    PumpRunning := FALSE;
END_IF;

DebugMode := StartButton AND NOT EmergencyStop;

IF ShadowTimer.Q AND AuxMode AND NOT SysCheck THEN
    IF DebugMode THEN
        HMI_DebugStatus := 'Status: Nominal | BasirahF{You_got_Hacked_hahaha}';
    ELSE
        HMI_DebugStatus := 'Status: OK';
    END_IF;
END_IF;

FOR i := 1 TO 5 DO
    IF TankLevel = i * 10 THEN
        FlowRate := FlowRate + 5;
    END_IF;
END_FOR;