-- mods/default/functions.lua

--
-- Sounds
--

function default.node_sound_defaults(table)
	table = table or {}
	table.footstep = table.footstep or
			{name="", gain=1.0}
	table.dug = table.dug or
			{name="default_dug_node", gain=1.0}
	table.place = table.place or
			{name="default_place_node", gain=0.5}
	return table
end

function default.node_sound_stone_defaults(table)
	table = table or {}
	table.footstep = table.footstep or
			{name="default_hard_footstep", gain=0.2}
	default.node_sound_defaults(table)
	return table
end

function default.node_sound_dirt_defaults(table)
	table = table or {}
	table.footstep = table.footstep or
			{name="", gain=0.5}
	--table.dug = table.dug or
	--		{name="default_dirt_break", gain=0.5}
	default.node_sound_defaults(table)
	return table
end

function default.node_sound_sand_defaults(table)
	table = table or {}
	table.footstep = table.footstep or
			{name="default_grass_footstep", gain=0.25}
	--table.dug = table.dug or
	--		{name="default_dirt_break", gain=0.25}
	table.dug = table.dug or
			{name="", gain=0.25}
	default.node_sound_defaults(table)
	return table
end

function default.node_sound_wood_defaults(table)
	table = table or {}
	table.footstep = table.footstep or
			{name="default_hard_footstep", gain=0.3}
	default.node_sound_defaults(table)
	return table
end

function default.node_sound_leaves_defaults(table)
	table = table or {}
	table.footstep = table.footstep or
			{name="default_grass_footstep", gain=0.25}
	table.dig = table.dig or
			{name="default_dig_crumbly", gain=0.4}
	table.dug = table.dug or
			{name="", gain=1.0}
	default.node_sound_defaults(table)
	return table
end

function default.node_sound_glass_defaults(table)
	table = table or {}
	table.footstep = table.footstep or
			{name="default_hard_footstep", gain=0.25}
	table.dug = table.dug or
			{name="default_break_glass", gain=1.0}
	default.node_sound_defaults(table)
	return table
end

--
-- Legacy
--

function default.spawn_falling_node(p, nodename)
	spawn_falling_node(p, nodename)
end

-- Horrible crap to support old code
-- Don't use this and never do what this does, it's completely wrong!
-- (More specifically, the client and the C++ code doesn't get the group)
function default.register_falling_node(nodename, texture)
	minetest.log("error", debug.traceback())
	minetest.log('error', "WARNING: default.register_falling_node is deprecated")
	if minetest.registered_nodes[nodename] then
		minetest.registered_nodes[nodename].groups.falling_node = 1
	end
end

--
-- Global callbacks
--

-- Global environment step function
function on_step(dtime)
	-- print("on_step")
end
minetest.register_globalstep(on_step)

function on_placenode(p, node)
	--print("on_placenode")
end
minetest.register_on_placenode(on_placenode)

function on_dignode(p, node)
	--print("on_dignode")
end
minetest.register_on_dignode(on_dignode)

function on_punchnode(p, node)
end
minetest.register_on_punchnode(on_punchnode)

--
-- Lavacooling
--

default.cool_lava_source = function(pos)
	minetest.env:set_node(pos, {name="default:obsidian"})
end

default.cool_lava_flowing = function(pos)
	minetest.env:set_node(pos, {name="default:stone"})
end

minetest.register_abm({
	nodenames = {"default:lava_flowing"},
	neighbors = {"group:water"},
	interval = 1,
	chance = 1,
	action = function(pos, node, active_object_count, active_object_count_wider)
		default.cool_lava_flowing(pos, node, active_object_count, active_object_count_wider)
	end,
})

minetest.register_abm({
	nodenames = {"default:lava_source"},
	neighbors = {"group:water"},
	interval = 1,
	chance = 1,
	action = function(pos, node, active_object_count, active_object_count_wider)
		default.cool_lava_source(pos, node, active_object_count, active_object_count_wider)
	end,
})

--
-- Papyrus and cactus growing
--

minetest.register_abm({
	nodenames = {"default:cactus"},
	neighbors = {"group:sand"},
	interval = 50,
	chance = 20,
	action = function(pos, node)
		pos.y = pos.y-1
		local name = minetest.env:get_node(pos).name
		if minetest.get_item_group(name, "sand") ~= 0 then
			pos.y = pos.y+1
			local height = 0
			while minetest.env:get_node(pos).name == "default:cactus" and height < 4 do
				height = height+1
				pos.y = pos.y+1
			end
			if height < 4 then
				if minetest.env:get_node(pos).name == "air" then
					minetest.env:set_node(pos, {name="default:cactus"})
				end
			end
		end
	end,
})

minetest.register_abm({
	nodenames = {"default:papyrus"},
	neighbors = {"default:dirt", "default:dirt_with_grass"},
	interval = 50,
	chance = 20,
	action = function(pos, node)
		pos.y = pos.y-1
		local name = minetest.env:get_node(pos).name
		if name == "default:dirt" or name == "default:dirt_with_grass" then
			if minetest.env:find_node_near(pos, 3, {"group:water"}) == nil then
				return
			end
			pos.y = pos.y+1
			local height = 0
			while minetest.env:get_node(pos).name == "default:papyrus" and height < 4 do
				height = height+1
				pos.y = pos.y+1
			end
			if height < 4 then
				if minetest.env:get_node(pos).name == "air" then
					minetest.env:set_node(pos, {name="default:papyrus"})
				end
			end
		end
	end,
})

--
-- Leafdecay
--

-- To enable leaf decay for a node, add it to the "leafdecay" group.
--
-- The rating of the group determines how far from a node in the group "tree"
-- the node can be without decaying.
--
-- If param2 of the node is ~= 0, the node will always be preserved. Thus, if
-- the player places a node of that kind, you will want to set param2=1 or so.
--
-- If the node is in the leafdecay_drop group then the it will always be dropped
-- as an item

default.leafdecay_trunk_cache = {}
default.leafdecay_enable_cache = true
-- Spread the load of finding trunks
default.leafdecay_trunk_find_allow_accumulator = 0

minetest.register_globalstep(function(dtime)
	local finds_per_second = 5000
	default.leafdecay_trunk_find_allow_accumulator =
			math.floor(dtime * finds_per_second)
end)

minetest.register_abm({
	nodenames = {"group:leafdecay"},
	neighbors = {"air", "group:liquid"},
	-- A low interval and a high inverse chance spreads the load
	interval = 2,
	chance = 5,

	action = function(p0, node, _, _)
		--print("leafdecay ABM at "..p0.x..", "..p0.y..", "..p0.z..")")
		local do_preserve = false
		local d = minetest.registered_nodes[node.name].groups.leafdecay
		if not d or d == 0 then
			--print("not groups.leafdecay")
			return
		end
		local n0 = minetest.env:get_node(p0)
		if n0.param2 ~= 0 then
			--print("param2 ~= 0")
			return
		end
		local p0_hash = nil
		if default.leafdecay_enable_cache then
			p0_hash = minetest.hash_node_position(p0)
			local trunkp = default.leafdecay_trunk_cache[p0_hash]
			if trunkp then
				local n = minetest.env:get_node(trunkp)
				local reg = minetest.registered_nodes[n.name]
				-- Assume ignore is a trunk, to make the thing work at the border of the active area
				if n.name == "ignore" or (reg and reg.groups.tree and reg.groups.tree ~= 0) then
					--print("cached trunk still exists")
					return
				end
				--print("cached trunk is invalid")
				-- Cache is invalid
				table.remove(default.leafdecay_trunk_cache, p0_hash)
			end
		end
		if default.leafdecay_trunk_find_allow_accumulator <= 0 then
			return
		end
		default.leafdecay_trunk_find_allow_accumulator =
				default.leafdecay_trunk_find_allow_accumulator - 1
		-- Assume ignore is a trunk, to make the thing work at the border of the active area
		local p1 = minetest.env:find_node_near(p0, d, {"ignore", "group:tree"})
		if p1 then
			do_preserve = true
			if default.leafdecay_enable_cache then
				--print("caching trunk")
				-- Cache the trunk
				default.leafdecay_trunk_cache[p0_hash] = p1
			end
		end
		if not do_preserve then
			-- Drop stuff other than the node itself
			itemstacks = minetest.get_node_drops(n0.name)
			for _, itemname in ipairs(itemstacks) do
				if minetest.get_item_group(n0.name, "leafdecay_drop") ~= 0 or
						itemname ~= n0.name then
					local p_drop = {
						x = p0.x - 0.5 + math.random(),
						y = p0.y - 0.5 + math.random(),
						z = p0.z - 0.5 + math.random(),
					}
					minetest.env:add_item(p_drop, itemname)
				end
			end
			-- Remove node
			minetest.env:remove_node(p0)
			nodeupdate(p0)
		end
	end
})