import time
import krpc

conn = krpc.connect(name="Sub-orbital flight")

vessel = conn.space_center.active_vessel

vessel.auto_pilot.target_pitch_and_heading(90, 90)
vessel.auto_pilot.engaged = True
vessel.control.throttle = 1
time.sleep(1)

print("Launch!")
vessel.control.activate_next_stage()

fuel_amount = conn.get_call(vessel.resources.amount, "SolidFuel")
expr = conn.krpc.Expression.less_than(
    conn.krpc.Expression.call(fuel_amount), conn.krpc.Expression.constant_float(0.1)
)
event = conn.krpc.add_event(expr)
with event.condition:
    event.wait()
print("Booster separation")
vessel.control.activate_next_stage()

mean_altitude = conn.get_call(getattr, vessel.flight(), "mean_altitude")
expr = conn.krpc.Expression.greater_than(
    conn.krpc.Expression.call(mean_altitude),
    conn.krpc.Expression.constant_double(10000),
)
event = conn.krpc.add_event(expr)
with event.condition:
    event.wait()

print("Gravity turn")
vessel.auto_pilot.target_pitch_and_heading(60, 90)

apoapsis_altitude = conn.get_call(getattr, vessel.orbit, "apoapsis_altitude")
expr = conn.krpc.Expression.greater_than(
    conn.krpc.Expression.call(apoapsis_altitude),
    conn.krpc.Expression.constant_double(100000),
)
event = conn.krpc.add_event(expr)
with event.condition:
    event.wait()

print("Launch stage separation")
vessel.control.throttle = 0
time.sleep(1)
vessel.control.activate_next_stage()
vessel.auto_pilot.engaged = False

srf_altitude = conn.get_call(getattr, vessel.flight(), "surface_altitude")
expr = conn.krpc.Expression.less_than(
    conn.krpc.Expression.call(srf_altitude), conn.krpc.Expression.constant_double(1000)
)
event = conn.krpc.add_event(expr)
with event.condition:
    event.wait()

vessel.control.activate_next_stage()

while vessel.flight(vessel.orbit.body.reference_frame).vertical_speed < -0.1:
    print("Altitude = %.1f meters" % vessel.flight().surface_altitude)
    time.sleep(1)
print("Landed!")