@lazyglobal off.
wait until ship:unpacked.
rcs off.
lock throttle to 0.

runoncepath("0:/lib/common.ks").
runoncepath("0:/lib/moonmath.ks").
runoncepath("0:/lib/stage/atlas.ks").
runoncepath("0:/lib/stage/centaur.ks").
runoncepath("0:/lib/stage/probe.ks").

local state is lex().

local function ship_volume {
    return ship:rootpart:getmodule("kosprocessor"):volume.
}

local function phase {
    switch to ship_volume().
    if not ship_volume():exists("state.json") {
        set_phase("prelaunch").
    }
    set state to readjson("state.json").
    return state["phase"].
}

local function set_phase {
    parameter new_phase.
    switch to ship_volume().
    set state["phase"] to new_phase.
    writejson(state, "state.json").
    kuniverse:quicksaveto("moon-impactor-"+new_phase).
}

if phase() = "prelaunch" {
    local target_inclination is max(moon:obt:inclination,ship:latitude).
    local target_alt is 500_000.
    set state["azimuth"] to launch_azimuth(target_inclination, target_alt).

    local launch_params is moonmath:calculate_launch(target_inclination, state["azimuth"], target_alt).
    local launch_time is launch_params:launch_time.
    set state["moon_altitude"] to launch_params:moon_altitude.
    set state["departure_ra"] to launch_params:burn_longitude.
    print "Departing for moon at " + state["departure_ra"] + " right ascension".

    wait 2.

    until launch_time - time:seconds < 10 {
        print "Not ready to launch yet, warping...".
        warpto(launch_time-9).
        wait 0.
        wait until warp = 0.
        wait until kuniverse:timewarp:issettled.
        print "Maybe done warping?".
    }
    wait until time:seconds > launch_time.

    atlas:launch(state["azimuth"], target_alt, 4).
    stage.
    set_phase("circularize").
}

if phase() = "circularize" {
    centaur:orbit(state["azimuth"]).
    centaur:power_down().

    wait 1.
    set_phase("parkingorbit").
}

local function ship_ra {
    return mod(ship:longitude + ship:body:rotationangle + 360, 360).
}

if phase() = "parkingorbit" {
    local transfer_dv is hohmann_transfer_dv(earth, ship:altitude, state["moon_altitude"]).
    local burn_time is centaur:burn_time(transfer_dv / 2).
    local burn_angle is (burn_time / ship:obt:period) * 360.
    local burn_ra is mod(state["departure_ra"] - burn_angle + 360, 360).


    // Just in case our departure point is RIGHT HERE, we want to go around at least once.
    set warpmode to "physics".
    set warp to 3.
    wait until abs(ship_ra() - burn_ra) > 16.
    set warp to 0.
    wait until kuniverse:timewarp:issettled.
    wait 1.

    // Rails warp until we're nearish to the burn point
    print "Warping to dLongitude < 15".
    set warpmode to "rails".
    set warp to 2.
    wait until abs(ship_ra() - burn_ra) < 15.
    set warp to 0.
    wait until kuniverse:timewarp:issettled.
    wait 1.

    // Physics warp until we're nearish-er
    print "Warping to dLongitude < 4".
    set warpmode to "physics".
    set warp to 3.
    wait until abs(ship_ra() - burn_ra) < 4.
    set warp to 0.
    wait until kuniverse:timewarp:issettled.
    wait 1.

    centaur:power_up().
    rcs on.
    lock steering to ship:prograde.
    wait until ship_ra() >= burn_ra.
    print "Moon altitude is: " + state["moon_altitude"].
    print "Transfer DV is: " + transfer_dv.
    centaur:transfer_burn(state["moon_altitude"]).
    wait 1.

    set_phase("pretransfer").
}

if phase() = "pretransfer" {
    rcs on.
    panels on.
    stage.
    wait 1.
    probe:power_up().
    lock steering to sun:direction.
    wait 1.
    wait until steering_locked().
    wait 1.
    rcs off.
    probe:power_down().
    wait 1.

    set_phase("transfer").
}

if phase() = "transfer" {
    set warpmode to "rails".
    warpto(eta:transition + time:seconds).
    wait until ship:obt:body = moon.
    wait until kuniverse:timewarp:issettled.

    set_phase("lunar_arrival").
}

if phase() = "lunar_arrival" {
    stage.
    probe:capture_burn().

    set_phase("lunar_deploy").
}

if phase() = "lunar_deploy" {
    probe:power_up().
    lock steering to sun:direction.
    wait 1.
    wait until steering_locked().
    wait 1.
    rcs off.
    probe:power_down().

    set_phase("done").
}


if phase() <> "done" {
    print "Phase logic failed, expected to be in phase '" + phase() + "'".
}

print "Done".