-- This module implements/replaces

-- [[Template:Lunar quadrangle]]

-- [[Template:Mars quadrangle]]

-- [[Template:Venus quadrangle]]

local p = {}



local function moonquad(lat, lon)

	local function LQ(n)

		if n < 10 then 

			return 'LQ0' .. n

		else 

			return 'LQ' .. n

		end

	end

	-- Note: requires positive longitude coordinates

	if lat > 65 then

		return LQ(1)

	elseif lat > 30 then

		if lon >= 180 then

			return LQ(2 + math.floor( (lon - 180) / 60 ) )

		else

			return LQ(5 + math.floor( lon / 60 ) )

		end

	elseif lat >= 0 then

		if lon >= 180 then

			return LQ(8 + math.floor( (lon - 180) / 45 ) )

		else

			return LQ(12 + math.floor( lon / 45 ) )

		end

	elseif lat >= -30 then

		if lon >= 180 then

			return LQ(16 + math.floor( (lon - 180) / 45 ) )

		else

			return LQ(20 + math.floor( lon / 45 ) )

		end

	elseif lat >= -65 then

		if lon >= 180 then

			return LQ(24 + math.floor( (lon - 180) / 60 ) )

		else

			return LQ(27 + math.floor( lon / 60 ) )

		end

	else

		return LQ(30)

	end



	return 'Error'

end



local function marsquad(lat, lon)

	-- Note: requires positive longitude coordinates

	if lat > 65 then 

		return 'Mare Boreum'

	elseif lat > 30 then 

		if lon < 60 then return 'Ismenius Lacus'

		elseif lon < 120 then return 'Casius'

		elseif lon < 180 then return 'Cebrenia'

		elseif lon < 240 then return 'Diacria'

		elseif lon < 300 then return 'Arcadia'

		else return 'Mare Acidalium' end

	elseif lat >= 0 then 

		if lon < 45 then return 'Arabia'

		elseif lon <  90 then return 'Syrtis Major'

		elseif lon < 135 then return 'Amenthes'

		elseif lon < 180 then return 'Elysium'

		elseif lon < 225 then return 'Amazonis'

		elseif lon < 270 then return 'Tharsis'

		elseif lon < 315 then return 'Lunae Palus'

		else return 'Oxia Palus' end

	elseif lat >= -30 then 

		if lon < 45 then return 'Sinus Sabaeus'

		elseif lon <  90 then return 'Iapygia'

		elseif lon < 135 then return 'Mare Tyrrhenum'

		elseif lon < 180 then return 'Aeolis'

		elseif lon < 225 then return 'Memnonia'

		elseif lon < 270 then return 'Phoenicis Lacus'

		elseif lon < 315 then return 'Coprates'

		else return 'Margaritifer Sinus' end

	elseif lat >= -65 then 

		if lon < 60 then return 'Noachis'

		elseif lon < 120 then return 'Hellas'

		elseif lon < 180 then return 'Eridania'

		elseif lon < 240 then return 'Phaethontis'

		elseif lon < 300 then return 'Thaumasia'

		else return 'Argyre' end

	else

		return 'Mare Australe'

	end

end



local function mercuryquad(lat, lon)

	-- Note: requires positive longitude coordinates

	if lat >= 66 then

		return 'Borealis'

	elseif lat >= 21 then

		if lon < 90 then return 'Hokusai'

		elseif lon < 180 then return 'Raditladi'

		elseif lon < 270 then return 'Shakespeare'

		else return 'Victoria' end

	elseif lat > -21 then

		if lon < 72 then return 'Derain'

		elseif lon < 144 then return 'Eminescu'

		elseif lon < 216 then return 'Tolstoj'

		elseif lon < 288 then return 'Beethoven'

		else return 'Kuiper' end

	elseif lat > -66 then

		if lon < 90 then return 'Debussy'

		elseif lon < 180 then return 'Neruda'

		elseif lon < 270 then return 'Michelangelo'

		else return 'Discovery' end

	else

		return 'Bach'

	end



	return 'Error'

end



local function venusquad(lat, lon)

	-- Note: requires positive longitude coordinates

	if lat > 57 then

		return 'Ishtar Terra'

	elseif lat >= 0 then

		if lon < 60 or lon >= 300 then return 'Sedna Planitia'

		elseif lon < 180 then return 'Niobe Planitia'

		else return 'Guinevere Planitia' end

	elseif lat >= -57 then

		if lon < 60  or lon >= 300 then return 'Lavinia Planitia'

		elseif lon < 180 then return 'Aphrodite Terra'

		else return 'Helen Planitia' end

	else

		return 'Lada Terra'

	end

end



local function quad_name(lat, lon, globe)

	-- lower case

	globe = globe:lower() or ''



	-- convert to numbers

	lat = tonumber(lat) or ''

	lon = tonumber(lon) or ''



	-- get the quad name

	if lat ~= '' and lon ~= '' and globe ~= '' then

		if lon < 0 then lon = lon + 360 end

		if lon < 0 or lon > 360 then

			return 'Error'

		end

		if globe == 'mars' then

			return marsquad(lat, lon)

		elseif globe == 'mercury' then

			return mercuryquad(lat, lon)

		elseif globe == 'moon' then

			return moonquad(lat, lon)

		elseif globe == 'venus' then

			return venusquad(lat, lon)

		end

	end



	return 'Error'

end



function p.category(frame)

	local args = frame.args

	local res = quad_name(args'lat' or '', args'lon' or '', args'globe' or '')

	

	if res ~= 'Error' then

		if args'nameonly' and args'nameonly' ~= '' then

			return res

		else

			return '[[Category:' .. res .. ' quadrangle]]'

		end

	end



	return '<span class="error">Error</span>'

end



function p.name(frame)

	local args = frame.args

	local res = quad_name(args'lat' or '', args'lon' or '', args'globe' or '')

	

	if res ~= 'Error' then

		return res

	end

	return '<span class="error">Error</span>'

end



return p