VoxeLibre/mods/ITEMS/mcl_farming/shared_functions.lua

function mcl_farming:add_plant(full_grown, names, interval, chance)
	minetest.register_abm({
		nodenames = names,
		interval = interval,
		chance = chance,
		action = function(pos, node)
			pos.y = pos.y-1
			if minetest.get_node(pos).name ~= "mcl_farming:soil_wet" and math.random(0, 9) > 0 then
				return
			end
			pos.y = pos.y+1
			if not minetest.get_node_light(pos) then
				return
			end
			if minetest.get_node_light(pos) < 10 then
				return
			end
			local step = nil
			for i,name in ipairs(names) do
				if name == node.name then
					step = i
					break
				end
			end
			if step == nil then
				return
			end
			local new_node = {name=names[step+1]}
			if new_node.name == nil then
				new_node.name = full_grown
			end
			minetest.set_node(pos, new_node)
		end
	})
end

function mcl_farming:place_seed(itemstack, placer, pointed_thing, plantname)
	local pt = pointed_thing
	if not pt then
		return
	end
	if pt.type ~= "node" then
		return
	end

	-- Use pointed node's on_rightclick function first, if present
	local node = minetest.get_node(pt.under)
	if placer and not placer:get_player_control().sneak then
		if minetest.registered_nodes[node.name] and minetest.registered_nodes[node.name].on_rightclick then
			return minetest.registered_nodes[node.name].on_rightclick(pt.under, node, placer, itemstack) or itemstack
		end
	end

	local pos = {x=pt.above.x, y=pt.above.y-1, z=pt.above.z}
	local farmland = minetest.get_node(pos)
	pos= {x=pt.above.x, y=pt.above.y, z=pt.above.z}
	local place_s = minetest.get_node(pos)


	if string.find(farmland.name, "mcl_farming:soil") and string.find(place_s.name, "air")  then
		minetest.add_node(pos, {name=plantname})
	else
		return
	end

	if not minetest.setting_getbool("creative_mode") then
		itemstack:take_item()
	end
	return itemstack
end


--[[ Helper function to create a gourd (e.g. melon, pumpkin), the connected stem nodes as

- full_unconnected_stem: itemstring of the full-grown but unconnceted stem node. This node must already be done
- connected_stem_basename: prefix of the itemstrings used for the 4 connected stem nodes to create
- stem_itemstring: Desired itemstring of the fully-grown unconnected stem node
- stem_def: Partial node definition of the fully-grown unconnected stem node. Many fields are already defined. You need to add `tiles` and `description` at minimum. Don't define on_construct without good reason
- stem_drop: Drop probability table for all stem
- gourd_itemstring: Desired itemstring of the full gourd node
- gourd_def: (almost) full definition of the gourd node. This function will add after_dig_node to the definition for unconnecting any connected stems
- grow_interval: Will attempt to grow a gourd periodically at this interval in seconds
- grow_chance: Chance of 1/grow_chance to grow a gourd next to the full unconnected stem after grow_interval has passed. Must be a natural number
]]

function mcl_farming:add_gourd(full_unconnected_stem, connected_stem_basename, stem_itemstring, stem_def, stem_drop, gourd_itemstring, gourd_def, grow_interval, grow_chance)

	local connected_stem_names = { 
		connected_stem_basename .. "_r",
		connected_stem_basename .. "_l",
		connected_stem_basename .. "_t",
		connected_stem_basename .. "_b",
	}

	local neighbors = {
		{ x=-1, y=0, z=0 },
		{ x=1, y=0, z=0 },
		{ x=0, y=0, z=-1 },
		{ x=0, y=0, z=1 },
	}

	-- Connect the stem at stempos to the first neighboring gourd block.
	-- No-op if not a stem or no gourd block found
	local try_connect_stem = function(stempos)
		local stem = minetest.get_node(stempos)
		if stem.name ~= full_unconnected_stem then
			return false
		end
		for n=1, #neighbors do
			local offset = neighbors[n]
			local blockpos = vector.add(stempos, offset)
			local block = minetest.get_node(blockpos)
			if block.name == gourd_itemstring then
				if offset.x == 1 then
					minetest.set_node(stempos, {name=connected_stem_names[1]})
				elseif offset.x == -1 then
					minetest.set_node(stempos, {name=connected_stem_names[2]})
				elseif offset.z == 1 then
					minetest.set_node(stempos, {name=connected_stem_names[3]})
				elseif offset.z == -1 then
					minetest.set_node(stempos, {name=connected_stem_names[4]})
				end
				return true
			end
		end
	end

	-- Register gourd
	if not gourd_def.after_dig_node then
		gourd_def.after_dig_node = function(blockpos, oldnode, oldmetadata, user)
			-- Disconnect any connected stems, turning them back to normal stems
			for n=1, #neighbors do
				local offset = neighbors[n]
				local expected_stem = connected_stem_names[n]
				local stempos = vector.add(blockpos, offset)
				local stem = minetest.get_node(stempos)
				if stem.name == expected_stem then
					minetest.add_node(stempos, {name=full_unconnected_stem})
					try_connect_stem(stempos)
				end
			end
		end
	end
	if not gourd_def.on_construct then
		gourd_def.on_construct = function(blockpos)
			-- Connect all unconnected stems at full size
			for n=1, #neighbors do
				local stempos = vector.add(blockpos, neighbors[n])
				try_connect_stem(stempos)
			end
		end
	end
	minetest.register_node(gourd_itemstring, gourd_def)

	-- Register unconnected stem

	-- Default values for the stem definition
	if not stem_def.selection_box then
		stem_def.selection_box = {
			type = "fixed",
			fixed = {
				{-0.15, -0.5, -0.15, 0.15, 0.5, 0.15}
			},
		}
	end
	if not stem_def.paramtype then
		stem_def.paramtype = "light"
	end
	if not stem_def.drawtype then
		stem_def.drawtype = "plantlike"
	end
	if stem_def.walkable == nil then
		stem_def.walkable = false
	end
	if stem_def.sunlight_propagates == nil then
		stem_def.sunlight_propagates = true
	end
	if stem_def.drop == nil then
		stem_def.drop = stem_drop
	end
	if stem_def.groups == nil then
		stem_def.groups = {dig_immediate=3, not_in_creative_inventory=1, attached_node=1, dig_by_water=1}
	end
	if stem_def.sounds == nil then
		stem_def.sounds = mcl_sounds.node_sound_leaves_defaults()
	end

	if not stem_def.on_construct then
		stem_def.on_construct = function(stempos)
			-- Connect stem to gourd (if possible)
			try_connect_stem(stempos)
		end
	end
	minetest.register_node(stem_itemstring, stem_def)

	-- Register connected stems

	local connected_stem_tiles = {
		{ "blank.png", --top
		"blank.png", -- bottom
		"blank.png", -- right
		"blank.png", -- left
		"farming_tige_connect.png", -- back
		"farming_tige_connect.png^[transformFX90" --front
		},
		{ "blank.png", --top
		"blank.png", -- bottom
		"blank.png", -- right
		"blank.png", -- left
		"farming_tige_connect.png^[transformFX90", --back
		"farming_tige_connect.png", -- front
		},
		{ "blank.png", --top
		"blank.png", -- bottom
		"farming_tige_connect.png^[transformFX90", -- right
		"farming_tige_connect.png", -- left
		"blank.png", --back
		"blank.png", -- front
		},
		{ "blank.png", --top
		"blank.png", -- bottom
		"farming_tige_connect.png", -- right
		"farming_tige_connect.png^[transformFX90", -- left
		"blank.png", --back
		"blank.png", -- front
		}
	}
	local connected_stem_nodebox = {
		{-0.5, -0.5, 0, 0.5, 0.5, 0},
		{-0.5, -0.5, 0, 0.5, 0.5, 0},
		{0, -0.5, -0.5, 0, 0.5, 0.5},
		{0, -0.5, -0.5, 0, 0.5, 0.5},
	}
	local connected_stem_selectionbox = {
		{-0.1, -0.5, -0.1, 0.5, 0.2, 0.1},
		{-0.5, -0.5, -0.1, 0.1, 0.2, 0.1},
		{-0.1, -0.5, -0.1, 0.1, 0.2, 0.5},
		{-0.1, -0.5, -0.5, 0.1, 0.2, 0.1},
	}

	for i=1, 4 do
		minetest.register_node(connected_stem_names[i], {
			_doc_items_create_entry = false,
			paramtype = "light",
			sunlight_propagates = true,
			walkable = false,
			drop = stem_drop,
			drawtype = "nodebox",
			paramtype = "light",
			node_box = {
				type = "fixed",
				fixed = connected_stem_nodebox[i]
			},
			selection_box = {
				type = "fixed",
				fixed = connected_stem_selectionbox[i]
			},
			tiles = connected_stem_tiles[i],
			groups = {dig_immediate=3, not_in_creative_inventory=1 ,dig_by_water=1},
			sounds = mcl_sounds.node_sound_leaves_defaults(),
			_mcl_blast_resistance = 0,
		})
	end

	minetest.register_abm({
		label = "Grow gourd stem to gourd ("..full_unconnected_stem.." → "..gourd_itemstring..")",
		nodenames = {full_unconnected_stem},
		neighbors = {"air"},
		interval = grow_interval,
		chance = grow_chance,
		action = function(stempos)
			local light = minetest.get_node_light(stempos)
			if light and light > 10 then
				-- Check the four neighbors and filter out neighbors where gourds can't grow
				local neighbors = {
					{ x=-1, y=0, z=0 },
					{ x=1, y=0, z=0 },
					{ x=0, y=0, z=-1 },
					{ x=0, y=0, z=1 },
				}
				for n=#neighbors, 1, -1 do
					local offset = neighbors[n]
					local blockpos = vector.add(stempos, offset)
					local floorpos = { x=blockpos.x, y=blockpos.y-1, z=blockpos.z }
					local floor = minetest.get_node(floorpos)
					local block = minetest.get_node(blockpos)
					local soilgroup = minetest.get_item_group(floor.name, "soil")
					if not ((floor.name=="mcl_core:dirt_with_grass" or floor.name=="mcl_core:dirt" or soilgroup == 2 or soilgroup == 3) and block.name == "air") then
						table.remove(neighbors, n)
					end
				end

				-- Pumpkins need at least 1 free neighbor to grow
				if #neighbors > 0 then
					-- From the remaining neighbors, grow randomly
					local r = math.random(1, #neighbors)
					local offset = neighbors[r]
					local blockpos = vector.add(stempos, offset)
					local p2
					if offset.x == 1 then
						minetest.set_node(stempos, {name=connected_stem_names[1]})
						p2 = 3
					elseif offset.x == -1 then
						minetest.set_node(stempos, {name=connected_stem_names[2]})
						p2 = 1
					elseif offset.z == 1 then
						minetest.set_node(stempos, {name=connected_stem_names[3]})
						p2 = 2
					elseif offset.z == -1 then
						minetest.set_node(stempos, {name=connected_stem_names[4]})
						p2 = 0
					end
					if gourd_def.paramtype2 == "facedir" then
						minetest.add_node(blockpos, {name=gourd_itemstring, param2=p2})
					else
						minetest.add_node(blockpos, {name=gourd_itemstring})
					end
				end
			end
		end,
	})
end