-- jovianmoons.celx
--
-- Copyright (C) 2008, Chris Laurel, claurel@gmail.com
--
-- Script to highlight orbits of the various groups of Jovian moons
--
-- Moons without official IAU names are not included. Lists are
-- based on information from a Wikipedia article on the moons of
-- Jupiter: http://en.wikipedia.org/wiki/Moons_of_Jupiter

function intro()
   local message = [[
  Jovian Satellite Groups
  
  Use the number keys to toggle the orbits of various groups
  of Jovian satellites.

  1: Inner satellites
  2: Galilean satellites
  3: Himalia group
  4: Ananke group
  5: Carme group
  6: Pasiphae group
  ESC: End script
  
  Orbits are not shown for satellites without official IAU names
  or where the membership in a group is questionable.

  Press any key to continue...
  ]]
  celestia:print(message, 120, -1, 1, 7, -4)
end

-- Intro function from Harald Schmidt's timestepkeys script.
intro_finished = false
function end_intro()
  intro_finished = true
  celestia:print("", 0.1)
  celestia_keyboard_callback = keyhandler
end
celestia_keyboard_callback = end_intro


inner = {
   "Sol/Jupiter/Metis",
   "Sol/Jupiter/Adrastea",
   "Sol/Jupiter/Amalthea",
   "Sol/Jupiter/Thebe"
}

galilean = {
   "Sol/Jupiter/Io",
   "Sol/Jupiter/Europa",
   "Sol/Jupiter/Ganymede",
   "Sol/Jupiter/Callisto"
}

himalia = {
   "Sol/Jupiter/Himalia",
   "Sol/Jupiter/Leda",
   "Sol/Jupiter/Lysithea",
   "Sol/Jupiter/Elara"
}

ananke = {
   "Sol/Jupiter/Ananke",
   "Sol/Jupiter/Praxidike",
   "Sol/Jupiter/Iocaste",
   "Sol/Jupiter/Harpalyke",
   "Sol/Jupiter/Thyone",
   "Sol/Jupiter/Euanthe",
   "Sol/Jupiter/Euporie"
}

carme = {
   "Sol/Jupiter/Carme",
   "Sol/Jupiter/Pasithee",
   "Sol/Jupiter/Chaldene",
   "Sol/Jupiter/Arche",
   "Sol/Jupiter/Isonoe",
   "Sol/Jupiter/Erinome",
   "Sol/Jupiter/Kale",
   "Sol/Jupiter/Aitne",
   "Sol/Jupiter/Taygete",
   "Sol/Jupiter/Kalyke",
   "Sol/Jupiter/Eukelade",
   "Sol/Jupiter/Kallichore"
}

pasiphae = {
   "Sol/Jupiter/Eurydome",
   "Sol/Jupiter/Pasiphae",
   "Sol/Jupiter/Hegemone",
   "Sol/Jupiter/Sponde",
   "Sol/Jupiter/Cyllene",
   "Sol/Jupiter/Megaclite",
   "Sol/Jupiter/Callirhoe",
   "Sol/Jupiter/Sinope",
   "Sol/Jupiter/Autonoe",
   "Sol/Jupiter/Aoede",
   "Sol/Jupiter/Kore"
}


function enable_orbits(t, r, g, b)
   for i, name in ipairs(t) do
      local moon = celestia:find(name)
      if moon then
	 moon:setorbitvisibility("always")
	 moon:setorbitcoloroverridden(true)
	 moon:setorbitcolor(r, g, b)
      end
   end
end


function disable_orbits(t)
   for i, name in ipairs(t) do
      local moon = celestia:find(name)
      if moon then
	 moon:setorbitvisibility("normal")
	 moon:setorbitcoloroverridden(false)
      end
   end
end


function toggle_orbits(t, r, g, b)
   -- Test whether the orbit of the first satellite in the
   -- group has a color override and decide whether to
   -- enable or disable based on that.
   local name = t[1]
   local moon = celestia:find(name)
   if (moon:orbitcoloroverridden()) then
      disable_orbits(t)
   else
      enable_orbits(t, r, g, b)
   end
end


function keyhandler(input)
    local ch = string.sub(input, 1, 1)
    if (ch == "1") then
       celestia:flash("Inner satellites")
       toggle_orbits(inner, 1, 0.6, 0)
       return true
    elseif (ch == "2") then
       celestia:flash("Galilean satellites")
       toggle_orbits(galilean, 1, 1, 0)
       return true
    elseif (ch == "3") then
       celestia:flash("Himalia group")
       toggle_orbits(himalia, 0.2, 1, 0)
       return true
    elseif (ch == "4") then
       celestia:flash("Ananke group")
       toggle_orbits(ananke, 0.7, 1, 0.5)
       return true
    elseif (ch == "5") then
       celestia:flash("Carme group")
       toggle_orbits(carme, 0.5, 0.8, 1)
       return true
    elseif (ch == "6") then
       celestia:flash("Pasiphae group")
       toggle_orbits(pasiphae, 0.8, 0.5, 1)
       return true
    else
       return false
    end
end

function disable_all()
   disable_orbits(inner)
   disable_orbits(galilean)
   disable_orbits(himalia)
   disable_orbits(ananke)
   disable_orbits(carme)
   disable_orbits(pasiphae)
end

disable_all()

celestia:setrenderflags({orbits = true})
celestia:setorbitflags({Moon = false})

intro()
--celestia_keyboard_callback = keyhandler
celestia:requestkeyboard(true)
while true do
  wait(1)
end

disable_all()