# Maik Justus < fg # mjustus : de >, based on bo105.nas by Melchior FRANZ, < mfranz # aon : at >

if (!contains(globals, "cprint")) {
  globals.cprint = func {};
}

var optarg   = aircraft.optarg;
var makeNode = aircraft.makeNode;

var sin      = func(a) { math.sin(a * math.pi / 180.0) }
var cos      = func(a) { math.cos(a * math.pi / 180.0) }
var pow      = func(v, w) { math.exp(math.ln(v) * w) }
var npow     = func(v, w) { math.exp(math.ln(abs(v)) * w) * (v < 0 ? -1 : 1) }
var clamp    = func(v, min = 0, max = 1) { v < min ? min : v > max ? max : v }
var normatan = func(x) { math.atan2(x, 1) * 2 / math.pi }

# timers ============================================================
var turbine_timer = aircraft.timer.new("/sim/time/hobbs/turbines", 10);
aircraft.timer.new("/sim/time/hobbs/helicopter", nil).start();

# engines/rotor =====================================================
var state                 = props.globals.getNode("sim/model/mi2/state");
var engine                = props.globals.getNode("sim/model/mi2/engine");
var rotor                 = props.globals.getNode("controls/engines/engine/magnetos");
var rotor_rpm             = props.globals.getNode("rotors/main/rpm");
var torque                = props.globals.getNode("rotors/gear/total-torque", 1);
var collective            = props.globals.getNode("controls/engines/engine[0]/throttle");
var turbine               = props.globals.getNode("sim/model/mi2/turbine-rpm-pct", 1);
var torque_pct            = props.globals.getNode("sim/model/mi2/torque-pct", 1);
var stall                 = props.globals.getNode("rotors/main/stall", 1);
var stall_filtered        = props.globals.getNode("rotors/main/stall-filtered", 1);
var torque_sound_filtered = props.globals.getNode("rotors/gear/torque-sound-filtered", 1);
var target_rel_rpm        = props.globals.getNode("controls/rotor/reltarget", 1);
var max_rel_torque        = props.globals.getNode("controls/rotor/maxreltorque", 1);
var cone                  = props.globals.getNode("rotors/main/cone-deg", 1);
var cone1                 = props.globals.getNode("rotors/main/cone1-deg", 1);
var cone2                 = props.globals.getNode("rotors/main/cone2-deg", 1);
var cone3                 = props.globals.getNode("rotors/main/cone3-deg", 1);
var cone4                 = props.globals.getNode("rotors/main/cone4-deg", 1);

# state:
# 0 off
# 1 engine startup
# 2 engine startup with small torque on rotor
# 3 engine idle
# 4 engine accel
# 5 engine sound loop

var update_state = func {
  var s = state.getValue();
  var new_state = arg[0];
  if (new_state == (s+1)) {
    state.setValue(new_state);
    if (new_state == (1)) {
      settimer(func { update_state(2) }, 2);
      interpolate(engine, 0.03, 0.1, 0.002, 0.3, 0.02, 0.1, 0.003, 0.7, 0.03, 0.1, 0.01, 0.7);
    } else {
      if (new_state == (2)) {
        settimer(func { update_state(3) }, 3);
        rotor.setValue(1);
        max_rel_torque.setValue(0.01);
        target_rel_rpm.setValue(0.002);
        interpolate(engine, 0.05, 0.2, 0.03, 1, 0.07, 0.1, 0.04, 0.9, 0.02, 0.5);
      } else {
        if (new_state == (3)) {
          if (rotor_rpm.getValue() > 100) {
            #rotor is running at high rpm, so accel. engine faster
            max_rel_torque.setValue(1);
            target_rel_rpm.setValue(1.03);
            state.setValue(5);
            interpolate(engine, 1.03, 10);
          } else {
            settimer(func { update_state(4) }, 7);
            max_rel_torque.setValue(0.05);
            target_rel_rpm.setValue(0.02);
            interpolate(engine, 0.07, 0.1, 0.03, 0.25, 0.075, 0.2, 0.08, 1, 0.06,2);
          }
        } else {
          if (new_state == (4)) {
            settimer(func { update_state(5) }, 30);
            max_rel_torque.setValue(0.25);
            target_rel_rpm.setValue(0.8);
          } else {
              if (new_state == (5)) {
              max_rel_torque.setValue(1);
              target_rel_rpm.setValue(1.03);
            }
          }
        }
      }
    }
  }
}

var engines = func {
  if (props.globals.getNode("sim/crashed",1).getBoolValue()) {
    return;
  }
  var s = state.getValue();
  if (arg[0] == 1) {
    if (s == 0) {
      update_state(1);
    }
  } else {
    rotor.setValue(0);           # engines stopped
    state.setValue(0);
    interpolate(engine, 0, 4);
  }
}

var update_engine = func {
  if (state.getValue() > 3 ) {
    interpolate (engine,  clamp( rotor_rpm.getValue() / 235 , 0.05, target_rel_rpm.getValue() ), 0.25 );
  }
}

var update_rotor_cone_angle = func {
  r = rotor_rpm.getValue();
  #print("r  = ", r);

  var f = r / 186;
  #print("f1 = ", f);

  f = clamp (f, 0 , 1);
  #print("f2 = ", f);

  c = cone.getValue();
  #print("c  = ", c);

  cone1.setDoubleValue( (c * 1.00) + (f * c));
  cone2.setDoubleValue( (c * 0.10) + (f * c));
  cone3.setDoubleValue( (c * 0.15) + (f * c));
  cone4.setDoubleValue( (c * 0.20) + (f * c));
}

# torquemeter
var torque_val = 0;
torque.setDoubleValue(0);

var update_torque = func(dt) {
  var f = dt / (0.2 + dt);
  torque_val = torque.getValue() * f + torque_val * (1 - f);
  torque_pct.setDoubleValue(torque_val / 5300);
}

# sound =============================================================
# stall sound
var stall_val = 0;
stall.setDoubleValue(0);

var update_stall = func(dt) {
  var s = stall.getValue();
  if (s < stall_val) {
    var f = dt / (0.3 + dt);
    stall_val = s * f + stall_val * (1 - f);
  } else {
    stall_val = s;
  }
  var c = collective.getValue();
  stall_filtered.setDoubleValue(stall_val + 0.006 * (1 - c));
}


# modify sound by torque
var torque_val = 0;

var update_torque_sound_filtered = func(dt) {
  var t = torque.getValue();
  t = clamp(t * 0.000001);
  t = t*0.25 + 0.75;
  var r = clamp(rotor_rpm.getValue()*0.02-1);
  torque_sound_filtered.setDoubleValue(t*r);
}

# skid slide sound
var Skid = {
  new : func(n) {
    var m = { parents : [Skid] };
    var soundN     = props.globals.getNode("sim/sound", 1).getChild("slide", n, 1);
    var gearN      = props.globals.getNode("gear", 1).getChild("gear", n, 1);

    m.compressionN = gearN.getNode("compression-norm", 1);
    m.rollspeedN   = gearN.getNode("rollspeed-ms", 1);
    m.frictionN    = gearN.getNode("ground-friction-factor", 1);
    m.wowN         = gearN.getNode("wow", 1);
    m.volumeN      = soundN.getNode("volume", 1);
    m.pitchN       = soundN.getNode("pitch", 1);

    m.compressionN.setDoubleValue(0);
    m.rollspeedN.setDoubleValue(0);
    m.frictionN.setDoubleValue(0);
    m.volumeN.setDoubleValue(0);
    m.pitchN.setDoubleValue(0);
    m.wowN.setBoolValue(1);
    m.self         = n;
    return m;
  },
  update : func {
    me.wowN.getBoolValue() or return;
    var rollspeed = abs(me.rollspeedN.getValue());
    me.pitchN.setDoubleValue(rollspeed * 0.6);

    var s = normatan(20 * rollspeed);
    var f = clamp((me.frictionN.getValue() - 0.5) * 2);
    var c = clamp(me.compressionN.getValue() * 2);
    me.volumeN.setDoubleValue(s * f * c * 2);
    #if (!me.self) {
    #	cprint("33;1", sprintf("S=%0.3f  F=%0.3f  C=%0.3f  >>  %0.3f", s, f, c, s * f * c));
    #}
  },
};

var skid = [];
for (var i = 0; i < 3; i += 1) {
  append(skid, Skid.new(i));
}

var update_slide = func {
  forindex (var i; skid) {
    skid[i].update();
  }
}

# crash handler =====================================================
#var load = nil;
var crash = func {
  if (arg[0]) {
    # crash
    setprop("rotors/main/rpm", 0);
    setprop("rotors/main/blade[0]/flap-deg", -60);
    setprop("rotors/main/blade[1]/flap-deg", -50);
    setprop("rotors/main/blade[2]/flap-deg", -40);
    setprop("rotors/main/blade[3]/flap-deg", -30);
    setprop("rotors/main/blade[0]/incidence-deg", -30);
    setprop("rotors/main/blade[1]/incidence-deg", -20);
    setprop("rotors/main/blade[2]/incidence-deg", -50);
    setprop("rotors/main/blade[3]/incidence-deg", -55);
    setprop("rotors/tail/rpm", 0);
    strobe_switch.setValue(0);
    beacon_switch.setValue(0);
    nav_light_switch.setValue(0);
    rotor.setValue(0);
    torque_pct.setValue(torque_val = 0);
    stall_filtered.setValue(stall_val = 0);
    state.setValue(0);
  } else {
    # uncrash (for replay)
    setprop("rotors/tail/rpm", 1500);
    setprop("rotors/main/rpm", 235);
    for (i = 0; i < 4; i += 1) {
      setprop("rotors/main/blade[" ~ i ~ "]/flap-deg", 0);
      setprop("rotors/main/blade[" ~ i ~ "]/incidence-deg", 0);
    }
    strobe_switch.setValue(1);
    beacon_switch.setValue(1);
    rotor.setValue(1);
    state.setValue(5);
  }
}

# "manual" rotor animation for flight data recorder replay ============
var rotor_step = props.globals.getNode("sim/model/mi2/rotor-step-deg");
var blade1_pos = props.globals.getNode("rotors/main/blade[0]/position-deg", 1);
var blade2_pos = props.globals.getNode("rotors/main/blade[1]/position-deg", 1);
var blade3_pos = props.globals.getNode("rotors/main/blade[2]/position-deg", 1);
var blade4_pos = props.globals.getNode("rotors/main/blade[3]/position-deg", 1);
var rotorangle = 0;

var rotoranim_loop = func {
  i = rotor_step.getValue();
  if (i >= 0.0) {
    blade1_pos.setValue(rotorangle);
    blade2_pos.setValue(rotorangle + 60);
    blade3_pos.setValue(rotorangle + 120);
    blade4_pos.setValue(rotorangle + 180);
    rotorangle += i;
    settimer(rotoranim_loop, 0.1);
  }
}

var init_rotoranim = func {
  if (rotor_step.getValue() >= 0.0) {
    settimer(rotoranim_loop, 0.1);
  }
}

# view management ===================================================

var elapsedN  = props.globals.getNode("/sim/time/elapsed-sec", 1);
var flap_mode = 0;
var down_time = 0;
controls.flapsDown = func(v) {
  if (!flap_mode) {
    if (v < 0) {
      down_time = elapsedN.getValue();
      flap_mode = 1;
      dynamic_view.lookat(
        5,     # heading left
        -20,   # pitch up
        0,     # roll right
        0.2,   # right
        0.6,   # up
        0.85,  # back
        0.2,   # time
        55,    # field of view
      );
    } elsif (v > 0) {
      flap_mode = 2;
      var p = "/sim/view/dynamic/enabled";
      setprop(p, !getprop(p));
    }
  } else {
    if (flap_mode == 1) {
      if (elapsedN.getValue() < down_time + 0.2) {
        return;
      }
      dynamic_view.resume();
    }
    flap_mode = 0;
  }
}

# register function that may set me.heading_offset, me.pitch_offset, me.roll_offset,
# me.x_offset, me.y_offset, me.z_offset, and me.fov_offset
#
dynamic_view.register(func {
  var lowspeed = 1 - normatan(me.speedN.getValue() / 50);
  var r = sin(me.roll) * cos(me.pitch);

  me.heading_offset = (me.roll < 0 ? -50 : -30) * r * abs(r);

  me.pitch_offset = (me.pitch < 0 ? -50 : -50) * sin(me.pitch) * lowspeed + 15 * sin(me.roll) * sin(me.roll);

  me.roll_offset = -15 * r * lowspeed;
});

# main() ============================================================
var delta_time   = props.globals.getNode("/sim/time/delta-realtime-sec", 1);
var adf_rotation = props.globals.getNode("/instrumentation/adf/rotation-deg", 1);
var hi_heading   = props.globals.getNode("/instrumentation/heading-indicator/indicated-heading-deg", 1);

var main_loop = func {
  # adf_rotation.setDoubleValue(hi_heading.getValue());

  var dt = delta_time.getValue();
  update_torque(dt);
  update_stall(dt);
  update_torque_sound_filtered(dt);
  update_slide();
  update_engine();
  update_rotor_cone_angle();
  settimer(main_loop, 0);
}

var crashed       = 0;
var variant       = nil;
var doors         = nil;
var config_dialog = nil;

# initialization
setlistener("/sim/signals/fdm-initialized", func {

  init_rotoranim();
  collective.setDoubleValue(1);

  setlistener("/sim/signals/reinit", func {
    cmdarg().getBoolValue() and return;
    cprint("32;1", "reinit");
    turbine_timer.stop();
    collective.setDoubleValue(1);
    variant.scan();
    crashed = 0;
  });

  setlistener("sim/crashed", func {
    cprint("31;1", "crashed ", cmdarg().getValue());
    turbine_timer.stop();
    if (cmdarg().getBoolValue()) {
      crash(crashed = 1);
    }
  });

  setlistener("/sim/freeze/replay-state", func {
    cprint("33;1", cmdarg().getValue() ? "replay" : "pause");
    if (crashed) {
      crash(!cmdarg().getBoolValue())
    }
  });

  # the attitude indicator needs pressure
  # settimer(func { setprop("engines/engine/rpm", 3000) }, 8);

  main_loop();
});
