function riverdev_appletree(x, y, z, area, data)
	local c_tree = minetest.get_content_id("default:tree")
	local c_apple = minetest.get_content_id("default:apple")
	local c_appleleaf = minetest.get_content_id("riverdev:appleleaf")
	local top = 3 + math.random(2)
	for j = -2, top do
		if j == top - 1 or j == top then
			for k = -2, 2 do
				local vi = area:index(x - 2, y + j, z + k)
				local viu = area:index(x - 2, y + j - 1, z + k)
				for i = -2, 2 do
					if math.random() < 0.8 then
						data[vi] = c_appleleaf
						if j == top and math.random() < 0.04 then
							data[viu] = c_apple
						end
					end
					vi = vi + 1
					viu = viu + 1
				end
			end
		elseif j == top - 2 then
			for k = -1, 1 do
				local vi = area:index(x - 1, y + j, z + k)
				for i = -1, 1 do
					if math.abs(i) + math.abs(k) == 2 then
						data[vi] = c_tree
					end
					vi = vi + 1
				end
			end
		else
			local vi = area:index(x, y + j, z)
			data[vi] = c_tree
		end
	end
end

function riverdev_autumntree(x, y, z, area, data)
	local c_tree = minetest.get_content_id("default:tree")
	local c_yellowleaf = minetest.get_content_id("riverdev:yellowleaf")
	local c_yellowleafinit = minetest.get_content_id("riverdev:yellowleafinit")
	local top = 3 + math.random(2)
	for j = -2, top do
		if j == top - 1 or j == top then
			for k = -2, 2 do
				local vi = area:index(x - 2, y + j, z + k)
				for i = -2, 2 do
					if math.random() < 0.6 then
						data[vi] = c_yellowleaf
					end
					vi = vi + 1
				end
			end
		elseif j == top - 2 then
			for k = -1, 1 do
				local vi = area:index(x - 1, y + j, z + k)
				for i = -1, 1 do
					if math.abs(i) + math.abs(k) == 2 then
						data[vi] = c_tree
					end
					vi = vi + 1
				end
			end
		else
			local vi = area:index(x, y + j, z)
			data[vi] = c_tree
		end
	end
	local vi = area:index(x, y + top, z)
	data[vi] = c_yellowleafinit
end

function riverdev_pinetree(x, y, z, area, data)
	local c_pinetree = minetest.get_content_id("riverdev:pinetree")
	local c_needles = minetest.get_content_id("riverdev:needles")
	for j = -4, 14 do
		if j == 3 or j == 6 or j == 9 or j == 12 then
			for k = -2, 2 do
				local vi = area:index(x - 2, y + j, z + k)
				for i = -2, 2 do
					if math.abs(i) == 2 or math.abs(k) == 2 then
						data[vi] = c_needles
					end
					vi = vi + 1
				end
			end
		elseif j == 4 or j == 7 or j == 10 then
			for k = -1, 1 do
				local vi = area:index(x - 1, y + j, z + k)
				for i = -1, 1 do
					if not (i == 0 and j == 0) then
						data[vi] = c_needles
					end
					vi = vi + 1
				end
			end
		elseif j == 13 then
			for k = -1, 1 do
				local vi = area:index(x - 1, y + j, z + k)
				local via = area:index(x - 1, y + j + 1, z + k)
				for i = -1, 1 do
					if not (i == 0 and j == 0) then
						data[vi] = c_needles
						data[via] = c_needles
					end
					vi = vi + 1
					via = via + 1
				end
			end
		end
		local vi = area:index(x, y + j, z)
		data[vi] = c_pinetree
	end
	local vi = area:index(x, y + 15, z)
	local via = area:index(x, y + 16, z)
	data[vi] = c_needles
	data[via] = c_needles
end

function riverdev_flower(data, vi)
	local c_danwhi = minetest.get_content_id("flowers:dandelion_white")
	local c_danyel = minetest.get_content_id("flowers:dandelion_yellow")
	local c_rose = minetest.get_content_id("flowers:rose")
	local c_tulip = minetest.get_content_id("flowers:tulip")
	local c_geranium = minetest.get_content_id("flowers:geranium")
	local c_viola = minetest.get_content_id("flowers:viola")
	local rand = math.random(6)
	if rand == 1 then
		data[vi] = c_danwhi
	elseif rand == 2 then
		data[vi] = c_rose
	elseif rand == 3 then
		data[vi] = c_tulip
	elseif rand == 4 then
		data[vi] = c_danyel
	elseif rand == 5 then
		data[vi] = c_geranium
	else
		data[vi] = c_viola
	end
end

-- ABM

-- Appletree sapling

minetest.register_abm({
	nodenames = {"riverdev:appling"},
	interval = 31,
	chance = 5,
	action = function(pos, node)
		local x = pos.x
		local y = pos.y
		local z = pos.z
		local vm = minetest.get_voxel_manip()
		local pos1 = {x=x-2, y=y-2, z=z-2}
		local pos2 = {x=x+2, y=y+5, z=z+2}
		local emin, emax = vm:read_from_map(pos1, pos2)
		local area = VoxelArea:new({MinEdge=emin, MaxEdge=emax})
		local data = vm:get_data()

		riverdev_appletree(x, y, z, area, data)

		vm:set_data(data)
		vm:write_to_map()
		vm:update_map()
	end,
})

-- Pinetree sapling

minetest.register_abm({
	nodenames = {"riverdev:pineling"},
	interval = 29,
	chance = 5,
	action = function(pos, node)
		local x = pos.x
		local y = pos.y
		local z = pos.z
		local vm = minetest.get_voxel_manip()
		local pos1 = {x=x-2, y=y-4, z=z-2}
		local pos2 = {x=x+2, y=y+16, z=z+2}
		local emin, emax = vm:read_from_map(pos1, pos2)
		local area = VoxelArea:new({MinEdge=emin, MaxEdge=emax})
		local data = vm:get_data()

		riverdev_pinetree(x, y, z, area, data)

		vm:set_data(data)
		vm:write_to_map()
		vm:update_map()
	end,
})

-- Spawn yellow leaves on ground

minetest.register_abm({
	nodenames = {"riverdev:yellowleafinit"},
	interval = 13,
	chance = 1,
	action = function(pos, node)
		local x = pos.x
		local y = pos.y
		local z = pos.z
		local c_yellowleaf = minetest.get_content_id("riverdev:yellowleaf")
		local c_grass = minetest.get_content_id("riverdev:grass")
		local c_yellowleafgrass = minetest.get_content_id("riverdev:yellowleafgrass")

		local vm = minetest.get_voxel_manip()
		local pos1 = {x=x-3, y=y-12, z=z-3}
		local pos2 = {x=x+3, y=y, z=z+3}
		local emin, emax = vm:read_from_map(pos1, pos2)
		local area = VoxelArea:new({MinEdge=emin, MaxEdge=emax})
		local data = vm:get_data()

		local vi = area:index(x, y, z)
		data[vi] = c_yellowleaf
		for vi in area:iterp(pos1, pos2) do
			if data[vi] == c_grass then
				data[vi] = c_yellowleafgrass
			end
		end

		vm:set_data(data)
		vm:write_to_map()
		vm:update_map()
	end,
})