local S = minetest.get_translator("mcl_structures")
mcl_structures ={}
local rotations = {
	"0",
	"90",
	"180",
	"270"
}

local function ecb_place(blockpos, action, calls_remaining, param)
	if calls_remaining >= 1 then return end
	minetest.place_schematic(param.pos, param.schematic, param.rotation, param.replacements, param.force_placement, param.flags)
	if param.after_placement_callback and param.p1 and param.p2 then
		param.after_placement_callback(param.p1, param.p2, param.size, param.rotation, param.pr)
	end
end
mcl_structures.place_schematic = function(pos, schematic, rotation, replacements, force_placement, flags, after_placement_callback, pr)
	local s = loadstring(minetest.serialize_schematic(schematic, "lua", {lua_use_comments = false, lua_num_indent_spaces = 0}) .. " return(schematic)")()
	if s and s.size then
		local x, z = s.size.x, s.size.z
		if rotation then
			if rotation == "random" and pr then
				rotation = rotations[pr:next(1,#rotations)]
			end
			if rotation == "random" then
				x = math.max(x, z)
				z = x
			elseif rotation == "90" or rotation == "270" then
				x, z = z, x
			end
		end
		local p1 = {x=pos.x    , y=pos.y           , z=pos.z    }
		local p2 = {x=pos.x+x-1, y=pos.y+s.size.y-1, z=pos.z+z-1}
		minetest.log("verbose","[mcl_structures] size=" ..minetest.pos_to_string(s.size) .. ", rotation=" .. tostring(rotation) .. ", emerge from "..minetest.pos_to_string(p1) .. " to " .. minetest.pos_to_string(p2))
		local param = {pos=vector.new(pos), schematic=s, rotation=rotation, replacements=replacements, force_placement=force_placement, flags=flags, p1=p1, p2=p2, after_placement_callback = after_placement_callback, size=vector.new(s.size), pr=pr}
		minetest.emerge_area(p1, p2, ecb_place, param)
	end
end

mcl_structures.get_struct = function(file)
	local localfile = minetest.get_modpath("mcl_structures").."/schematics/"..file
	local file, errorload = io.open(localfile, "rb")
	if errorload ~= nil then
		minetest.log("error", '[mcl_structures] Could not open this struct: ' .. localfile)
		return nil
	end

	local allnode = file:read("*a")
	file:close()

	return allnode
end

-- Call on_construct on pos.
-- Useful to init chests from formspec.
local init_node_construct = function(pos)
	local node = minetest.get_node(pos)
	local def = minetest.registered_nodes[node.name]
	if def and def.on_construct then
		def.on_construct(pos)
		return true
	end
	return false
end

-- The call of Struct
mcl_structures.call_struct = function(pos, struct_style, rotation, pr)
	minetest.log("action","[mcl_structures] call_struct " .. struct_style.." at "..minetest.pos_to_string(pos))
	if not rotation then
		rotation = "random"
	end
	if struct_style == "desert_temple" then
		return mcl_structures.generate_desert_temple(pos, rotation, pr)
	elseif struct_style == "desert_well" then
		return mcl_structures.generate_desert_well(pos, rotation)
	elseif struct_style == "igloo" then
		return mcl_structures.generate_igloo(pos, rotation, pr)
	elseif struct_style == "witch_hut" then
		return mcl_structures.generate_witch_hut(pos, rotation)
	elseif struct_style == "ice_spike_small" then
		return mcl_structures.generate_ice_spike_small(pos, rotation)
	elseif struct_style == "ice_spike_large" then
		return mcl_structures.generate_ice_spike_large(pos, rotation)
	elseif struct_style == "boulder" then
		return mcl_structures.generate_boulder(pos, rotation, pr)
	elseif struct_style == "fossil" then
		return mcl_structures.generate_fossil(pos, rotation, pr)
	elseif struct_style == "end_exit_portal" then
		return mcl_structures.generate_end_exit_portal(pos, rotation)
	elseif struct_style == "end_portal_shrine" then
		return mcl_structures.generate_end_portal_shrine(pos, rotation, pr)
	elseif struct_style == "ruined_portal_large" then
		return mcl_structures.generate_ruined_portal_large(pos, rotation, pr)
	elseif struct_style == "ruined_portal_small" then
		return mcl_structures.generate_ruined_portal_small(pos, rotation, pr)
	end
end

mcl_structures.generate_desert_well = function(pos)
	local newpos = {x=pos.x,y=pos.y-2,z=pos.z}
	local path = minetest.get_modpath("mcl_structures").."/schematics/mcl_structures_desert_well.mts"
	return mcl_structures.place_schematic(newpos, path, "0", nil, true)
end

mcl_structures.generate_igloo = function(pos, rotation, pr)
	-- Place igloo
	local success, rotation = mcl_structures.generate_igloo_top(pos, pr)
	-- Place igloo basement with 50% chance
	local r = pr:next(1,2)
	if r == 1 then
		-- Select basement depth
		local dim = mcl_worlds.pos_to_dimension(pos)
		local buffer = pos.y - (mcl_vars.mg_lava_overworld_max + 10)
		if dim == "nether" then
			buffer = pos.y - (mcl_vars.mg_lava_nether_max + 10)
		elseif dim == "end" then
			buffer = pos.y - (mcl_vars.mg_end_min + 1)
		elseif dim == "overworld" then
			buffer = pos.y - (mcl_vars.mg_lava_overworld_max + 10)
		else
			return success
		end
		if buffer <= 19 then
			return success
		end
		local depth = pr:next(19, buffer)
		local bpos = {x=pos.x, y=pos.y-depth, z=pos.z}
		-- trapdoor position
		local tpos
		local dir, tdir
		if rotation == "0" then
			dir = {x=-1, y=0, z=0}
			tdir = {x=1, y=0, z=0}
			tpos = {x=pos.x+7, y=pos.y-1, z=pos.z+3}
		elseif rotation == "90" then
			dir = {x=0, y=0, z=-1}
			tdir = {x=0, y=0, z=-1}
			tpos = {x=pos.x+3, y=pos.y-1, z=pos.z+1}
		elseif rotation == "180" then
			dir = {x=1, y=0, z=0}
			tdir = {x=-1, y=0, z=0}
			tpos = {x=pos.x+1, y=pos.y-1, z=pos.z+3}
		elseif rotation == "270" then
			dir = {x=0, y=0, z=1}
			tdir = {x=0, y=0, z=1}
			tpos = {x=pos.x+3, y=pos.y-1, z=pos.z+7}
		else
			return success
		end
		local set_brick = function(pos)
			local c = pr:next(1, 3) -- cracked chance
			local m = pr:next(1, 10) -- chance for monster egg
			local brick
			if m == 1 then
				if c == 1 then
					brick = "mcl_monster_eggs:monster_egg_stonebrickcracked"
				else
					brick = "mcl_monster_eggs:monster_egg_stonebrick"
				end
			else
				if c == 1 then
					brick = "mcl_core:stonebrickcracked"
				else
					brick = "mcl_core:stonebrick"
				end
			end
			minetest.set_node(pos, {name=brick})
		end
		local ladder_param2 = minetest.dir_to_wallmounted(tdir)
		local real_depth = 0
		-- Check how deep we can actuall dig
		for y=1, depth-5 do
			real_depth = real_depth + 1
			local node = minetest.get_node({x=tpos.x,y=tpos.y-y,z=tpos.z})
			local def = minetest.registered_nodes[node.name]
			if (not def) or (not def.walkable) or (def.liquidtype ~= "none") or (not def.is_ground_content) then
				bpos.y = tpos.y-y+1
				break
			end
		end
		if real_depth <= 6 then
			return success
		end
		-- Place hidden trapdoor
		minetest.set_node(tpos, {name="mcl_doors:trapdoor", param2=20+minetest.dir_to_facedir(dir)}) -- TODO: more reliable param2
		-- Generate ladder to basement
		for y=1, real_depth-1 do
			set_brick({x=tpos.x-1,y=tpos.y-y,z=tpos.z  })
			set_brick({x=tpos.x+1,y=tpos.y-y,z=tpos.z  })
			set_brick({x=tpos.x  ,y=tpos.y-y,z=tpos.z-1})
			set_brick({x=tpos.x  ,y=tpos.y-y,z=tpos.z+1})
			minetest.set_node({x=tpos.x,y=tpos.y-y,z=tpos.z}, {name="mcl_core:ladder", param2=ladder_param2})
		end
		-- Place basement
		mcl_structures.generate_igloo_basement(bpos, rotation, pr)
	end
	return success
end

mcl_structures.generate_igloo_top = function(pos, pr)
	-- FIXME: This spawns bookshelf instead of furnace. Fix this!
	-- Furnace does ot work atm because apparently meta is not set. :-(
	local newpos = {x=pos.x,y=pos.y-1,z=pos.z}
	local path = minetest.get_modpath("mcl_structures").."/schematics/mcl_structures_igloo_top.mts"
	local rotation = tostring(pr:next(0,3)*90)
	return mcl_structures.place_schematic(newpos, path, rotation, nil, true), rotation
end

local function igloo_placement_callback(p1, p2, size, orientation, pr)
	local chest_offset
	if orientation == "0" then
		chest_offset = {x=5, y=1, z=5}
	elseif orientation == "90" then
		chest_offset = {x=5, y=1, z=3}
	elseif orientation == "180" then
		chest_offset = {x=3, y=1, z=1}
	elseif orientation == "270" then
		chest_offset = {x=1, y=1, z=5}
	else
		return
	end
	local size = {x=9,y=5,z=7}
	local lootitems = mcl_loot.get_multi_loot({
	{
		stacks_min = 1,
		stacks_max = 1,
		items = {
			{ itemstring = "mcl_core:apple_gold", weight = 1 },
		}
	},
	{
		stacks_min = 2,
		stacks_max = 8,
		items = {
			{ itemstring = "mcl_core:coal_lump", weight = 15, amount_min = 1, amount_max = 4 },
			{ itemstring = "mcl_core:apple", weight = 15, amount_min = 1, amount_max = 3 },
			{ itemstring = "mcl_farming:wheat_item", weight = 10, amount_min = 2, amount_max = 3 },
			{ itemstring = "mcl_core:gold_nugget", weight = 10, amount_min = 1, amount_max = 3 },
			{ itemstring = "mcl_mobitems:rotten_flesh", weight = 10 },
			{ itemstring = "mcl_tools:axe_stone", weight = 2 },
			{ itemstring = "mcl_core:emerald", weight = 1 },
		}
	}}, pr)

	local chest_pos = vector.add(p1, chest_offset)
	init_node_construct(chest_pos)
	local meta = minetest.get_meta(chest_pos)
	local inv = meta:get_inventory()
	mcl_loot.fill_inventory(inv, "main", lootitems, pr)
end

mcl_structures.generate_igloo_basement = function(pos, orientation, pr)
	-- TODO: Add brewing stand
	-- TODO: Add monster eggs
	-- TODO: Spawn villager and zombie villager
	local path = minetest.get_modpath("mcl_structures").."/schematics/mcl_structures_igloo_basement.mts"
	mcl_structures.place_schematic(pos, path, orientation, nil, true, nil, igloo_placement_callback, pr)
end

mcl_structures.generate_boulder = function(pos, rotation, pr)
	-- Choose between 2 boulder sizes (2×2×2 or 3×3×3)
	local r = pr:next(1, 10)
	local path
	if r <= 3 then
		path = minetest.get_modpath("mcl_structures").."/schematics/mcl_structures_boulder_small.mts"
	else
		path = minetest.get_modpath("mcl_structures").."/schematics/mcl_structures_boulder.mts"
	end

	local newpos = {x=pos.x,y=pos.y-1,z=pos.z}

	return minetest.place_schematic(newpos, path) -- don't serialize schematics for registered biome decorations, for MT 5.4.0, https://github.com/minetest/minetest/issues/10995
end

local function hut_placement_callback(p1, p2, size, orientation, pr)
	if not p1 or not p2 then return end
	local legs = minetest.find_nodes_in_area(p1, p2, "mcl_core:tree")
	for i = 1, #legs do
		while minetest.get_item_group(mcl_mapgen_core.get_node({x=legs[i].x, y=legs[i].y-1, z=legs[i].z}, true, 333333).name, "water") ~= 0 do
			legs[i].y = legs[i].y - 1
			minetest.swap_node(legs[i], {name = "mcl_core:tree", param2 = 2})
		end
	end
end

mcl_structures.generate_witch_hut = function(pos, rotation, pr)
	local path = minetest.get_modpath("mcl_structures").."/schematics/mcl_structures_witch_hut.mts"
	mcl_structures.place_schematic(pos, path, rotation, nil, true, nil, hut_placement_callback, pr)
end

mcl_structures.generate_ice_spike_small = function(pos)
	local path = minetest.get_modpath("mcl_structures").."/schematics/mcl_structures_ice_spike_small.mts"
	return minetest.place_schematic(pos, path, "random", nil, false) -- don't serialize schematics for registered biome decorations, for MT 5.4.0
end

mcl_structures.generate_ice_spike_large = function(pos)
	local path = minetest.get_modpath("mcl_structures").."/schematics/mcl_structures_ice_spike_large.mts"
	return minetest.place_schematic(pos, path, "random", nil, false) -- don't serialize schematics for registered biome decorations, for MT 5.4.0
end

mcl_structures.generate_fossil = function(pos, rotation, pr)
	-- Generates one out of 8 possible fossil pieces
	local newpos = {x=pos.x,y=pos.y-1,z=pos.z}
	local fossils = {
		"mcl_structures_fossil_skull_1.mts", -- 4×5×5
		"mcl_structures_fossil_skull_2.mts", -- 5×5×5
		"mcl_structures_fossil_skull_3.mts", -- 5×5×7
		"mcl_structures_fossil_skull_4.mts", -- 7×5×5
		"mcl_structures_fossil_spine_1.mts", -- 3×3×13
		"mcl_structures_fossil_spine_2.mts", -- 5×4×13
		"mcl_structures_fossil_spine_3.mts", -- 7×4×13
		"mcl_structures_fossil_spine_4.mts", -- 8×5×13
	}
	local r = pr:next(1, #fossils)
	local path = minetest.get_modpath("mcl_structures").."/schematics/"..fossils[r]
	return mcl_structures.place_schematic(newpos, path, "random", nil, true)
end

mcl_structures.generate_end_exit_portal = function(pos)
	local path = minetest.get_modpath("mcl_structures").."/schematics/mcl_structures_end_exit_portal.mts"
	return mcl_structures.place_schematic(pos, path, "0", nil, true)
end

local function shrine_placement_callback(p1, p2, size, rotation, pr)
	-- Find and setup spawner with silverfish
	local spawners = minetest.find_nodes_in_area(p1, p2, "mcl_mobspawners:spawner")
	for s=1, #spawners do
		local meta = minetest.get_meta(spawners[s])
		mcl_mobspawners.setup_spawner(spawners[s], "mobs_mc:silverfish")
	end

	-- Shuffle stone brick types
	local bricks = minetest.find_nodes_in_area(p1, p2, "mcl_core:stonebrick")
	for b=1, #bricks do
		local r_bricktype = pr:next(1, 100)
		local r_infested = pr:next(1, 100)
		local bricktype
		if r_infested <= 5 then
			if r_bricktype <= 30 then -- 30%
				bricktype = "mcl_monster_eggs:monster_egg_stonebrickmossy"
			elseif r_bricktype <= 50 then -- 20%
				bricktype = "mcl_monster_eggs:monster_egg_stonebrickcracked"
			else -- 50%
				bricktype = "mcl_monster_eggs:monster_egg_stonebrick"
			end
		else
			if r_bricktype <= 30 then -- 30%
				bricktype = "mcl_core:stonebrickmossy"
			elseif r_bricktype <= 50 then -- 20%
				bricktype = "mcl_core:stonebrickcracked"
			end
			-- 50% stonebrick (no change necessary)
		end
		if bricktype ~= nil then
			minetest.set_node(bricks[b], { name = bricktype })
		end
	end

	-- Also replace stairs
	local stairs = minetest.find_nodes_in_area(p1, p2, {"mcl_stairs:stair_stonebrick", "mcl_stairs:stair_stonebrick_outer", "mcl_stairs:stair_stonebrick_inner"})
	for s=1, #stairs do
		local stair = minetest.get_node(stairs[s])
		local r_type = pr:next(1, 100)
		if r_type <= 30 then -- 30% mossy
			if stair.name == "mcl_stairs:stair_stonebrick" then
				stair.name = "mcl_stairs:stair_stonebrickmossy"
			elseif stair.name == "mcl_stairs:stair_stonebrick_outer" then
				stair.name = "mcl_stairs:stair_stonebrickmossy_outer"
			elseif stair.name == "mcl_stairs:stair_stonebrick_inner" then
				stair.name = "mcl_stairs:stair_stonebrickmossy_inner"
			end
			minetest.set_node(stairs[s], stair)
		elseif r_type <= 50 then -- 20% cracky
			if stair.name == "mcl_stairs:stair_stonebrick" then
				stair.name = "mcl_stairs:stair_stonebrickcracked"
			elseif stair.name == "mcl_stairs:stair_stonebrick_outer" then
				stair.name = "mcl_stairs:stair_stonebrickcracked_outer"
			elseif stair.name == "mcl_stairs:stair_stonebrick_inner" then
				stair.name = "mcl_stairs:stair_stonebrickcracked_inner"
			end
			minetest.set_node(stairs[s], stair)
		end
		-- 50% no change
	end

	-- Randomly add ender eyes into end portal frames, but never fill the entire frame
	local frames = minetest.find_nodes_in_area(p1, p2, "mcl_portals:end_portal_frame")
	local eyes = 0
	for f=1, #frames do
		local r_eye = pr:next(1, 10)
		if r_eye == 1 then
			eyes = eyes + 1
			if eyes < #frames then
				local frame_node = minetest.get_node(frames[f])
				frame_node.name = "mcl_portals:end_portal_frame_eye"
				minetest.set_node(frames[f], frame_node)
			end
		end
	end
end

mcl_structures.generate_end_portal_shrine = function(pos, rotation, pr)
	local offset = {x=6, y=4, z=6}
	local size = {x=13, y=8, z=13}
	local newpos = { x = pos.x - offset.x, y = pos.y, z = pos.z - offset.z }

	local path = minetest.get_modpath("mcl_structures").."/schematics/mcl_structures_end_portal_room_simple.mts"
	mcl_structures.place_schematic(newpos, path, "0", nil, true, nil, shrine_placement_callback, pr)
end

local function ruined_portal_callback(p1, p2, size, rotation, pr)
	local biome_data = minetest.get_biome_data(p1)
	local biome_is_cold = (biome_data.heat < 15) or false
	local biome_name = minetest.get_biome_name(biome_data.biome)
	local biome_is_ocean = string.find(biome_name, "ocean") and true or false
	local r_boobytrapped = pr:next(1, 100)
	local nodes = minetest.find_nodes_in_area(p1, p2, {
		"mesecons_pistons:piston_normal_off",
		"mesecons_pistons:piston_sticky_off",
		"mcl_core:goldblock",
		"mcl_stairs:slab_goldblock",
		"mcl_stairs:slab_goldblock_double",
		"mcl_stairs:slab_goldblock_top",
		"mcl_stairs:stair_goldblock",
		"mcl_stairs:stair_goldblock_inner",
		"mcl_stairs:stair_goldblock_outer",
		"mcl_core:obsidian",
		"mcl_nether:netherrack",
		"mcl_core:lava_source",
		"mcl_core:stonebrick",
		"mcl_core:stonebrickcarved",
		"mcl_stairs:slab_stonebrick",
		"mcl_stairs:slab_stonebrick_top",
		"mcl_stairs:slab_stonebrick_double",
		"mcl_stairs:slab_stone",
		"mcl_stairs:slab_stone_top",
		"mcl_stairs:slab_stone_double",
		"mcl_stairs:stair_stonebrick",
		"mcl_stairs:stair_stonebrick_outer",
		"mcl_stairs:stair_stonebrick_inner",
		"mcl_walls:stonebrick",
		"mcl_walls:stonebrick_0",
		"mcl_walls:stonebrick_1",
		"mcl_walls:stonebrick_10",
		"mcl_walls:stonebrick_11",
		"mcl_walls:stonebrick_12",
		"mcl_walls:stonebrick_13",
		"mcl_walls:stonebrick_14",
		"mcl_walls:stonebrick_15",
		"mcl_walls:stonebrick_16",
		"mcl_walls:stonebrick_2",
		"mcl_walls:stonebrick_21",
		"mcl_walls:stonebrick_3",
		"mcl_walls:stonebrick_4",
		"mcl_walls:stonebrick_5",
		"mcl_walls:stonebrick_6",
		"mcl_walls:stonebrick_7",
		"mcl_walls:stonebrick_8",
		"mcl_walls:stonebrick_9"
	})
	for n=1, #nodes do
		local node = minetest.get_node(nodes[n])
		-- Rotate walls (needs to be done first)
		if rotation == "90" or rotation == "270" then
			if "mcl_walls:stonebrick_5" == node.name then
				node.name = "mcl_walls:stonebrick_10"
			elseif "mcl_walls:stonebrick_10" == node.name then
				node.name = "mcl_walls:stonebrick_5"
			end
			if "mcl_walls:stonebrick_16" == node.name then
				node.name = "mcl_walls:stonebrick_21"
			elseif "mcl_walls:stonebrick_21" == node.name then
				node.name = "mcl_walls:stonebrick_16"
			end
		end
		if (p1.y > mcl_vars.mg_overworld_min) and (p1.y < mcl_vars.mg_overworld_max) then
			local r_bricktype = pr:next(1, 100)
			-- Replace stone brick with mossy variants (30%)
			if r_bricktype <= 30 then -- 30%
				if "mcl_core:stonebrick" == node.name then
					node.name = "mcl_core:stonebrickmossy"
				elseif "mcl_stairs:slab_stonebrick" == node.name then
					node.name = "mcl_stairs:slab_stonebrickmossy"
				elseif "mcl_stairs:slab_stonebrick_top" == node.name then
					node.name = "mcl_stairs:slab_stonebrickmossy_top"
				elseif "mcl_stairs:slab_stonebrick_double" == node.name then
					node.name = "mcl_stairs:slab_stonebrickmossy_double"
				elseif "mcl_stairs:stair_stonebrick" == node.name then
					node.name = "mcl_stairs:stair_stonebrickmossy"
				elseif "mcl_stairs:stair_stonebrick_outer" == node.name then
					node.name = "mcl_stairs:stair_stonebrickmossy_outer"
				elseif "mcl_stairs:stair_stonebrick_inner" == node.name then
					node.name = "mcl_stairs:stair_stonebrickmossy_inner"
				elseif "mcl_walls:stonebrick" == node.name then
					node.name = "mcl_walls:stonebrickmossy"
				elseif "mcl_walls:stonebrick_0" == node.name then
					node.name = "mcl_walls:stonebrickmossy_0"
				elseif "mcl_walls:stonebrick_1" == node.name then
					node.name = "mcl_walls:stonebrickmossy_1"
				elseif "mcl_walls:stonebrick_10" == node.name then
					node.name = "mcl_walls:stonebrickmossy_10"
				elseif "mcl_walls:stonebrick_11" == node.name then
					node.name = "mcl_walls:stonebrickmossy_11"
				elseif "mcl_walls:stonebrick_12" == node.name then
					node.name = "mcl_walls:stonebrickmossy_12"
				elseif "mcl_walls:stonebrick_13" == node.name then
					node.name = "mcl_walls:stonebrickmossy_13"
				elseif "mcl_walls:stonebrick_14" == node.name then
					node.name = "mcl_walls:stonebrickmossy_14"
				elseif "mcl_walls:stonebrick_15" == node.name then
					node.name = "mcl_walls:stonebrickmossy_15"
				elseif "mcl_walls:stonebrick_16" == node.name then
					node.name = "mcl_walls:stonebrickmossy_16"
				elseif "mcl_walls:stonebrick_2" == node.name then
					node.name = "mcl_walls:stonebrickmossy_2"
				elseif "mcl_walls:stonebrick_21" == node.name then
					node.name = "mcl_walls:stonebrickmossy_21"
				elseif "mcl_walls:stonebrick_3" == node.name then
					node.name = "mcl_walls:stonebrickmossy_3"
				elseif "mcl_walls:stonebrick_4" == node.name then
					node.name = "mcl_walls:stonebrickmossy_4"
				elseif "mcl_walls:stonebrick_5" == node.name then
					node.name = "mcl_walls:stonebrickmossy_5"
				elseif "mcl_walls:stonebrick_6" == node.name then
					node.name = "mcl_walls:stonebrickmossy_6"
				elseif "mcl_walls:stonebrick_7" == node.name then
					node.name = "mcl_walls:stonebrickmossy_7"
				elseif "mcl_walls:stonebrick_8" == node.name then
					node.name = "mcl_walls:stonebrickmossy_8"
				elseif "mcl_walls:stonebrick_9" == node.name then
					node.name = "mcl_walls:stonebrickmossy_9"
				end
			-- Replace stone brick with cracked variants (20%)
			elseif r_bricktype <= 50 then -- 20%
				if "mcl_core:stonebrick" == node.name then
					node.name = "mcl_core:stonebrickcracked"
				elseif "mcl_stairs:slab_stonebrick" == node.name then
					node.name = "mcl_stairs:slab_stonebrickcracked"
				elseif "mcl_stairs:slab_stonebrick_top" == node.name then
					node.name = "mcl_stairs:slab_stonebrickcracked_top"
				elseif "mcl_stairs:slab_stonebrick_double" == node.name then
					node.name = "mcl_stairs:slab_stonebrickcracked_double"
				elseif "mcl_stairs:stair_stonebrick" == node.name then
					node.name = "mcl_stairs:stair_stonebrickcracked"
				elseif "mcl_stairs:stair_stonebrick_outer" == node.name then
					node.name = "mcl_stairs:stair_stonebrickcracked_outer"
				elseif "mcl_stairs:stair_stonebrick_inner" == node.name then
					node.name = "mcl_stairs:stair_stonebrickcracked_inner"
				end
			end
		end
		-- Booby trap all redstone mechanisms (20%)
		if r_boobytrapped <= 20 and (
			"mesecons_pistons:piston_normal_off" == node.name or
			"mesecons_pistons:piston_sticky_off" == node.name
		) then
			node.name = "mcl_tnt:tnt"
		-- Replace gold with air (30%)
		elseif (
			"mcl_core:goldblock" == node.name or
			"mcl_stairs:slab_goldblock" == node.name or
			"mcl_stairs:slab_goldblock_double" == node.name or
			"mcl_stairs:slab_goldblock_top" == node.name or
			"mcl_stairs:stair_goldblock" == node.name or
			"mcl_stairs:stair_goldblock_inner" == node.name or
			"mcl_stairs:stair_goldblock_outer" == node.name
		) then
			local r_air = pr:next(1,100)
			if r_air <= 30 then
				node.name = "air"
			end
		-- Replace obsidian with crying obsidian (20%)
		elseif "mcl_core:obsidian" == node.name then
			local r_crying = pr:next(1,100)
			if r_crying <= 30 then
				node.name = "mcl_nether:crying_obsidian"
			end
		-- Replace Nether rack with magma (7% if not cold)
		elseif "mcl_nether:netherrack" == node.name then
			if not biome_is_cold then
				local r_magma = pr:next(1,100)
				if r_magma <= 7 then
					node.name = "mcl_nether:magma"
				end
			end
		-- Replace lava (underwater: 100% magma / cold: 100% Nether rack / else: 20% magma)
		elseif "mcl_core:lava_source" == node.name then
			if biome_is_ocean and nodes[n].y < 0 then -- do not replace at surface
				node.name = "mcl_nether:magma"
			elseif biome_is_cold then
				node.name = "mcl_nether:netherrack"
			else
				local r_magma = pr:next(1,100)
				if r_magma <= 20 then
					node.name = "mcl_nether:magma"
				end
			end
		end
		-- Replace stone brick variants with (red) Nether brick in the Nether
		-- TODO: Replace stone brick variants with blackstone when we have it
		if (p1.y > mcl_vars.mg_nether_min) and (p1.y < mcl_vars.mg_nether_max) then
			if "mcl_core:stonebrick" == node.name then
				node.name = "mcl_nether:nether_brick"
			elseif "mcl_core:stonebrickcarved" == node.name then
				node.name = "mcl_nether:nether_brick_carved"
			elseif "mcl_stairs:slab_stonebrick" == node.name then
				node.name = "mcl_stairs:slab_nether_brick"
			elseif "mcl_stairs:slab_stonebrick_top" == node.name then
				node.name = "mcl_stairs:slab_nether_brick_top"
			elseif "mcl_stairs:slab_stonebrick_double" == node.name then
				node.name = "mcl_stairs:slab_nether_brick_double"
			elseif "mcl_stairs:slab_stone" == node.name then
				node.name = "mcl_stairs:slab_red_nether_brick"
			elseif "mcl_stairs:slab_stone_top" == node.name then
				node.name = "mcl_stairs:slab_red_nether_brick_top"
			elseif "mcl_stairs:slab_stone_double" == node.name then
				node.name = "mcl_stairs:slab_red_nether_brick_double"
			elseif "mcl_stairs:stair_stonebrick" == node.name then
				node.name = "mcl_stairs:stair_nether_brick"
			elseif "mcl_stairs:stair_stonebrick_outer" == node.name then
				node.name = "mcl_stairs:stair_nether_brick_outer"
			elseif "mcl_stairs:stair_stonebrick_inner" == node.name then
				node.name = "mcl_stairs:stair_nether_brick_inner"
			elseif "mcl_walls:stonebrick" == node.name then
				node.name = "mcl_walls:netherbrick"
			elseif "mcl_walls:stonebrick_0" == node.name then
				node.name = "mcl_walls:netherbrick_0"
			elseif "mcl_walls:stonebrick_1" == node.name then
				node.name = "mcl_walls:netherbrick_1"
			elseif "mcl_walls:stonebrick_10" == node.name then
				node.name = "mcl_walls:netherbrick_10"
			elseif "mcl_walls:stonebrick_11" == node.name then
				node.name = "mcl_walls:netherbrick_11"
			elseif "mcl_walls:stonebrick_12" == node.name then
				node.name = "mcl_walls:netherbrick_12"
			elseif "mcl_walls:stonebrick_13" == node.name then
				node.name = "mcl_walls:netherbrick_13"
			elseif "mcl_walls:stonebrick_14" == node.name then
				node.name = "mcl_walls:netherbrick_14"
			elseif "mcl_walls:stonebrick_15" == node.name then
				node.name = "mcl_walls:netherbrick_15"
			elseif "mcl_walls:stonebrick_16" == node.name then
				node.name = "mcl_walls:netherbrick_16"
			elseif "mcl_walls:stonebrick_2" == node.name then
				node.name = "mcl_walls:netherbrick_2"
			elseif "mcl_walls:stonebrick_21" == node.name then
				node.name = "mcl_walls:netherbrick_21"
			elseif "mcl_walls:stonebrick_3" == node.name then
				node.name = "mcl_walls:netherbrick_3"
			elseif "mcl_walls:stonebrick_4" == node.name then
				node.name = "mcl_walls:netherbrick_4"
			elseif "mcl_walls:stonebrick_5" == node.name then
				node.name = "mcl_walls:netherbrick_5"
			elseif "mcl_walls:stonebrick_6" == node.name then
				node.name = "mcl_walls:netherbrick_6"
			elseif "mcl_walls:stonebrick_7" == node.name then
				node.name = "mcl_walls:netherbrick_7"
			elseif "mcl_walls:stonebrick_8" == node.name then
				node.name = "mcl_walls:netherbrick_8"
			elseif "mcl_walls:stonebrick_9" == node.name then
				node.name = "mcl_walls:netherbrick_9"
			-- Replace lava with Nether lava
			elseif "mcl_core:lava_source" == node.name then
				node.name = "mcl_nether:nether_lava_source"
			end
		end
		minetest.set_node(nodes[n], node)
	end
	-- Add loot into chests.
	local chests = minetest.find_nodes_in_area(p1, p2, {
		"mcl_chests:chest_small",
		"mcl_chests:trapped_chest_small"
	})
	for c=1, #chests do
		local lootitems = mcl_loot.get_multi_loot({
		{
			stacks_min = 4,
			stacks_max = 8,
			items = {
				{ itemstring = "mcl_core:iron_nugget", weight = 46, amount_min = 9, amount_max = 18 },
				{ itemstring = "mcl_core:flint", weight = 46, amount_min = 1, amount_max = 4 },
				{ itemstring = "mcl_core:obsidian", weight = 46, amount_min = 1, amount_max = 2 },
				{ itemstring = "mcl_fire:fire_charge", weight = 46, },
				{ itemstring = "mcl_fire:flint_and_steel", weight = 46, },
				{ itemstring = "mcl_core:gold_nugget", weight = 21, amount_min = 4, amount_max = 24 },
				{ itemstring = "mcl_core:apple_gold", weight = 21 },
				-- TODO: enchanted golden axe / hoe / pickaxe / shovel / sword / helmet / chestplate / leggings / boots
				{ itemstring = "mcl_potions:speckled_melon", weight = 7, amount_min = 4, amount_max = 12 },
				{ itemstring = "mcl_farming:carrot_item_gold", weight = 7, amount_min = 4, amount_max = 12 },
				{ itemstring = "mcl_core:gold_ingot", weight = 7, amount_min = 2, amount_max = 6 },
				{ itemstring = "mcl_clock:clock", weight = 7, },
				{ itemstring = "mobs_mc:gold_horse_armor", weight = 7, },
				{ itemstring = "mcl_core:goldblock", weight = 2, amount_min = 1, amount_max = 2 },
				{ itemstring = "mcl_core:apple_gold_enchanted", weight = 2, },
			}
		}
		}, pr)

		local meta = minetest.get_meta(chests[c])
		init_node_construct(chests[c])
		local meta = minetest.get_meta(chests[c])
		local inv = meta:get_inventory()
		mcl_loot.fill_inventory(inv, "main", lootitems, pr)
	end
end

mcl_structures.generate_ruined_portal_large = function(pos, orientation, pr)
	-- Generates one out of 1 possible small ruined nether portals
	local newpos = {
		x = pos.x,
		y = pos.y - 10,
		z = pos.z
	}
	local portals = {
		"mcl_structures_ruined_portal_large_1.mts",
	}
	local r = pr:next(1, #portals)
	local path = minetest.get_modpath("mcl_structures") .. "/schematics/" .. portals[r]
	return mcl_structures.place_schematic(newpos, path, orientation, nil, true, nil, ruined_portal_callback, pr)
end

mcl_structures.generate_ruined_portal_small = function(pos, orientation, pr)
	-- Generates one out of 5 possible small ruined nether portals
	local newpos = {
		x = pos.x,
		y = pos.y - 4,
		z = pos.z
	}
	local portals = {
		"mcl_structures_ruined_portal_small_1.mts",
		"mcl_structures_ruined_portal_small_2.mts",
		"mcl_structures_ruined_portal_small_3.mts",
		"mcl_structures_ruined_portal_small_4.mts",
		"mcl_structures_ruined_portal_small_5.mts"
	}
	local r = pr:next(1, #portals)
	local path = minetest.get_modpath("mcl_structures") .. "/schematics/" .. portals[r]
	return mcl_structures.place_schematic(newpos, path, orientation, nil, true, nil, ruined_portal_callback, pr)
end

local function temple_placement_callback(p1, p2, size, rotation, pr)

	-- Delete cacti leftovers:
	local cactus_nodes = minetest.find_nodes_in_area_under_air(p1, p2, "mcl_core:cactus")
	if cactus_nodes and #cactus_nodes > 0 then
		for _, pos in pairs(cactus_nodes) do
			local node_below = minetest.get_node({x=pos.x, y=pos.y-1, z=pos.z})
			if node_below and node_below.name == "mcl_core:sandstone" then
				minetest.swap_node(pos, {name="air"})
			end
		end
	end

	-- Find chests.
	-- FIXME: Searching this large area just for the chets is not efficient. Need a better way to find the chests;
	-- probably let's just infer it from newpos because the schematic always the same.
	local chests = minetest.find_nodes_in_area(p1, p2, "mcl_chests:chest")

	-- Add desert temple loot into chests
	for c=1, #chests do
		local lootitems = mcl_loot.get_multi_loot({
		{
			stacks_min = 2,
			stacks_max = 4,
			items = {
				{ itemstring = "mcl_mobitems:bone", weight = 25, amount_min = 4, amount_max=6 },
				{ itemstring = "mcl_mobitems:rotten_flesh", weight = 25, amount_min = 3, amount_max=7 },
				{ itemstring = "mcl_mobitems:spider_eye", weight = 25, amount_min = 1, amount_max=3 },
				{ itemstack = mcl_enchanting.get_uniform_randomly_enchanted_book({"soul_speed"}), weight = 20, },
				{ itemstring = "mcl_mobitems:saddle", weight = 20, },
				{ itemstring = "mcl_core:apple_gold", weight = 20, },
				{ itemstring = "mcl_core:gold_ingot", weight = 15, amount_min = 2, amount_max = 7 },
				{ itemstring = "mcl_core:iron_ingot", weight = 15, amount_min = 1, amount_max = 5 },
				{ itemstring = "mcl_core:emerald", weight = 15, amount_min = 1, amount_max = 3 },
				{ itemstring = "", weight = 15, },
				{ itemstring = "mobs_mc:iron_horse_armor", weight = 15, },
				{ itemstring = "mobs_mc:gold_horse_armor", weight = 10, },
				{ itemstring = "mobs_mc:diamond_horse_armor", weight = 5, },
				{ itemstring = "mcl_core:diamond", weight = 5, amount_min = 1, amount_max = 3 },
				{ itemstring = "mcl_core:apple_gold_enchanted", weight = 2, },
			}
		},
		{
			stacks_min = 4,
			stacks_max = 4,
			items = {
				{ itemstring = "mcl_mobitems:bone", weight = 10, amount_min = 1, amount_max = 8 },
				{ itemstring = "mcl_mobitems:rotten_flesh", weight = 10, amount_min = 1, amount_max = 8 },
				{ itemstring = "mcl_mobitems:gunpowder", weight = 10, amount_min = 1, amount_max = 8 },
				{ itemstring = "mcl_core:sand", weight = 10, amount_min = 1, amount_max = 8 },
				{ itemstring = "mcl_mobitems:string", weight = 10, amount_min = 1, amount_max = 8 },
			}
		}}, pr)

		local meta = minetest.get_meta(chests[c])
		init_node_construct(chests[c])
		local meta = minetest.get_meta(chests[c])
		local inv = meta:get_inventory()
		mcl_loot.fill_inventory(inv, "main", lootitems, pr)
	end

	-- Initialize pressure plates and randomly remove up to 5 plates
	local pplates = minetest.find_nodes_in_area(p1, p2, "mesecons_pressureplates:pressure_plate_stone_off")
	local pplates_remove = 5
	for p=1, #pplates do
		if pplates_remove > 0 and pr:next(1, 100) >= 50 then
			-- Remove plate
			minetest.remove_node(pplates[p])
			pplates_remove = pplates_remove - 1
		else
			-- Initialize plate
			minetest.registered_nodes["mesecons_pressureplates:pressure_plate_stone_off"].on_construct(pplates[p])
		end
	end
end

mcl_structures.generate_desert_temple = function(pos, rotation, pr)
	-- No Generating for the temple ... Why using it ? No Change
	local path = minetest.get_modpath("mcl_structures").."/schematics/mcl_structures_desert_temple.mts"
	local newpos = {x=pos.x,y=pos.y-12,z=pos.z}
	local size = {x=22, y=24, z=22}
	if newpos == nil then
		return
	end
	mcl_structures.place_schematic(newpos, path, "random", nil, true, nil, temple_placement_callback, pr)
end

local registered_structures = {}

--[[ Returns a table of structure of the specified type.
Currently the only valid parameter is "stronghold".
Format of return value:
{
	{ pos = <position>, generated=<true/false> }, -- first structure
	{ pos = <position>, generated=<true/false> }, -- second structure
	-- and so on
}

TODO: Implement this function for all other structure types as well.
]]
mcl_structures.get_registered_structures = function(structure_type)
	if registered_structures[structure_type] then
		return table.copy(registered_structures[structure_type])
	else
		return {}
	end
end

-- Register a structures table for the given type. The table format is the same as for
-- mcl_structures.get_registered_structures.
mcl_structures.register_structures = function(structure_type, structures)
	registered_structures[structure_type] = structures
end

local function dir_to_rotation(dir)
	local ax, az = math.abs(dir.x), math.abs(dir.z)
	if ax > az then
		if dir.x < 0 then
			return "270"
		end
		return "90"
	end
	if dir.z < 0 then
		return "180"
	end
	return "0"
end

-- Debug command
minetest.register_chatcommand("spawnstruct", {
	params = "desert_temple | desert_well | igloo | witch_hut | boulder | ice_spike_small | ice_spike_large | fossil | end_exit_portal | end_portal_shrine | ruined_portal_large | ruined_portal_small",
	description = S("Generate a pre-defined structure near your position."),
	privs = {debug = true},
	func = function(name, param)
		local player = minetest.get_player_by_name(name)
		if not player then return end
		local pos = player:get_pos()
		if not pos then return end
		pos = vector.round(pos)
		local dir = minetest.yaw_to_dir(player:get_look_horizontal())
		local rot = dir_to_rotation(dir)
		local pr = PseudoRandom(pos.x+pos.y+pos.z)
		local errord = false
		local message = S("Structure placed.")
		if param == "desert_temple" then
			mcl_structures.generate_desert_temple(pos, rot, pr)
		elseif param == "desert_well" then
			mcl_structures.generate_desert_well(pos, rot, pr)
		elseif param == "igloo" then
			mcl_structures.generate_igloo(pos, rot, pr)
		elseif param == "witch_hut" then
			mcl_structures.generate_witch_hut(pos, rot, pr)
		elseif param == "boulder" then
			mcl_structures.generate_boulder(pos, rot, pr)
		elseif param == "fossil" then
			mcl_structures.generate_fossil(pos, rot, pr)
		elseif param == "ice_spike_small" then
			mcl_structures.generate_ice_spike_small(pos, rot, pr)
		elseif param == "ice_spike_large" then
			mcl_structures.generate_ice_spike_large(pos, rot, pr)
		elseif param == "end_exit_portal" then
			mcl_structures.generate_end_exit_portal(pos, rot, pr)
		elseif param == "end_portal_shrine" then
			mcl_structures.generate_end_portal_shrine(pos, rot, pr)
		elseif param == "ruined_portal_large" then
			mcl_structures.generate_ruined_portal_large(pos, rot, pr)
		elseif param == "ruined_portal_small" then
			mcl_structures.generate_ruined_portal_small(pos, rot, pr)
		elseif param == "" then
			message = S("Error: No structure type given. Please use “/spawnstruct <type>”.")
			errord = true
		else
			message = S("Error: Unknown structure type. Please use “/spawnstruct <type>”.")
			errord = true
		end
		minetest.chat_send_player(name, message)
		if errord then
			minetest.chat_send_player(name, S("Use /help spawnstruct to see a list of avaiable types."))
		end
	end
})