local max_depth = 31000
local cells = 10
local border = 10
local cell_size = math.floor((80 - border * 2) / cells)
local cells_y = math.floor(80 / cell_size)
local dead_space = 80 - cells_y * cell_size
local dungeon_depth = -1  -- close to y / 80


local dungeon_noise = {offset = 0, scale = 1, seed = -4082, spread = {x = 7, y = 7, z = 7}, octaves = 4, persist = 1, lacunarity = 2}


if fun_caves.path then
	dofile(fun_caves.path .. "/trophies.lua")
	dofile(fun_caves.path .. "/tesseract.lua")
end


-- dungeon floor, rooms
newnode = fun_caves.clone_node("default:cobble")
newnode.description = "Dungeon Stone"
newnode.legacy_mineral = false
newnode.groups.dungeon = 1
minetest.register_node("fun_caves:dungeon_floor_1", newnode)

-- dungeon floor, halls
newnode = fun_caves.clone_node("default:cobble")
newnode.description = "Dungeon Stone"
newnode.legacy_mineral = false
newnode.groups.dungeon = 1
newnode.drop = 'default:cobble'
minetest.register_node("fun_caves:dungeon_floor_2", newnode)

-- dungeon walls, basic
newnode = fun_caves.clone_node("default:cobble")
newnode.description = "Dungeon Stone"
newnode.groups.dungeon = 1
newnode.drop = 'default:cobble'
minetest.register_node("fun_caves:dungeon_wall_1", newnode)

-- dungeon walls, type 2
newnode = fun_caves.clone_node("default:cobble")
newnode.description = "Dungeon Stone"
newnode.groups.dungeon = 1
newnode.drop = 'default:cobble'
minetest.register_node("fun_caves:dungeon_wall_2", newnode)


local treasures = {
	{  level = 1,  rarity = 10,     name = 'default:apple 10',  },
	{  level = 1,  rarity = 120,    name = 'default:bronze_ingot 10',  },
	{  level = 1,  rarity = 30,     name = 'default:coal_lump 10',  },
	{  level = 1,  rarity = 85,     name = 'default:copper_ingot 10',  },
	{  level = 1,  rarity = 155,    name = 'default:diamond 10',  },
	{  level = 1,  rarity = 155,    name = 'default:gold_ingot 10',  },
	{  level = 1,  rarity = 200,    name = 'default:mese_crystal',          },
	{  level = 1,  rarity = 240,    name = 'default:obsidian',              },
	{  level = 1,  rarity = 85,     name = 'default:obsidian_shard',        },
	{  level = 1,  rarity = 450,    name = 'default:pick_diamond',          },
	{  level = 1,  rarity = 600,    name = 'default:pick_mese',             },
	{  level = 1,  rarity = 50,     name = 'default:steel_ingot 10',  },
	{  level = 1,  rarity = 450,    name = 'default:sword_diamond',         },
	{  level = 1,  rarity = 400,    name = 'default:sword_mese',            },
	{  level = 1,  rarity = 10,     name = 'default:wood 10',  },
	{  level = 1,  rarity = 400,    name = 'fun_caves:aquamarine',          },
	{  level = 1,  rarity = 400,    name = 'fun_caves:constant_flame',      },
	{  level = 1,  rarity = 400,    name = 'fun_caves:coral_gem',           },
	{  level = 1,  rarity = 400,    name = 'fun_caves:garnet',              },
	{  level = 2,  rarity = 960,    name = 'fun_caves:metallic_ice',        },
	{  level = 2,  rarity = 120,    name = 'fun_caves:eternal_ice_crystal', },
	{  level = 1,  rarity = 480,    name = 'fun_caves:moon_glass 10',  },
	{  level = 1,  rarity = 240,    name = 'fun_caves:moon_juice 10',  },
	{  level = 1,  rarity = 400,    name = 'fun_caves:moonstone',           },
	{  level = 1,  rarity = 5000,   name = 'fun_caves:philosophers_stone',  },
	{  level = 1,  rarity = 160,    name = 'fun_caves:pure_copper',         },
	{  level = 2,  rarity = 175,    name = 'fun_caves:silver_ingot 10',  },
	{  level = 1,  rarity = 960,    name = 'fun_caves:sky_iron',            },
	{  level = 1,  rarity = 120,    name = 'fun_caves:meteorite',           },
	{  level = 1,  rarity = 5000,   name = 'fun_caves:unobtainium',         },
}


if minetest.registered_entities['mobs_monster:stone_monster'] then
	treasures[#treasures+1] = { level = 1, rarity = 400, name = 'mobs_monster:stone_monster', }
end

if minetest.registered_entities['mobs_monster:dungeon_master'] then
	treasures[#treasures+1] = { level = 1, rarity = 400, name = 'mobs_monster:dungeon_master', }
end

local chest_formspec =
	"size[8,9]" ..
	default.gui_bg ..
	default.gui_bg_img ..
	default.gui_slots ..
	"list[current_name;main;0,0.3;8,4;]" ..
	"list[current_player;main;0,4.85;8,1;]" ..
	"list[current_player;main;0,6.08;8,3;8]" ..
	"listring[current_name;main]" ..
	"listring[current_player;main]" ..
	default.get_hotbar_bg(0,4.85)

local newnode = fun_caves.clone_node("default:chest")
newnode.description = "Treasure Chest"
newnode.on_construct = nil
newnode.drop = 'default:chest'
newnode.on_rightclick = function(pos, node, clicker, itemstack, pointed_thing)
	if not pos then
		return
	end

	local meta = minetest.get_meta(pos)
	if not meta then
		return
	end
	local depth = math.max(1, math.ceil(pos.y / -2000))
	local level = math.max(1, math.floor(pos.y / -4900))

	local ready = meta:get_string('formspec')
	if treasures and ready == '' then
		if minetest.get_modpath('tnt') and math.random(20) == 1 then
			minetest.set_node(pos, {name = 'tnt:tnt_burning'})
			local timer = minetest.get_node_timer(pos)
			if timer then
				timer:start(5)
			end
			minetest.sound_play("default_dig_crumbly", {pos = pos, gain = 0.5, max_hear_distance = 10})
			return
		end

		meta:set_string("formspec", chest_formspec)
		local inv = meta:get_inventory()
		inv:set_size("main", 8*4)
		local something
		for i = 1, 100 do
			for j = 1, 5 * depth do
				for _, tre in pairs(treasures) do
					if tre.name and tre.level and tre.rarity and tre.level <= level and math.random(tre.rarity) == 1 then
						inv:add_item('main', tre.name)
						something = true
					end
				end
			end

			if something then
				break
			end
		end
	end
end
minetest.register_node("fun_caves:coffer", newnode)


fun_caves.dungeon = function(minp_in, maxp_in, data, p2data, area, node, heightmap)
	if not (minp_in and maxp_in and data and area and node and heightmap and type(data) == 'table' and type(heightmap) == 'table') then
		return
	end

	local n = minetest.get_perlin(dungeon_noise):get2d({x=minp_in.x, y=minp_in.z})
	if not (n and type(n) == 'number') then
		return
	end

	if math.floor((n * 10000) % 13) ~= 1 then
		return
	end

	local center_off = cell_size * 4 + border
	if minp_in.y > -100 then
		local minp, maxp = minp_in, maxp_in
		local stair, avg, count = nil, 0, 0
		local index = 0
		for z = minp.z, maxp.z do
			for x = minp.x, maxp.x do
				index = index + 1

				if not heightmap[index] or type(heightmap[index]) ~= 'number' then
					return
				end

				if x > minp.x + center_off and x < maxp.x - center_off and z > minp.z + center_off and z < maxp.z - center_off and heightmap[index] >= minp.y and heightmap[index] < maxp.y - 2 then
					stair = true
					avg = avg + heightmap[index]
					count = count + 1
				end
			end
		end
		avg = math.ceil(avg / count)

		if stair then
			for z = -1, (cell_size * 2) do
				for x = -1, (cell_size * 2) do
					local ivm = area:index(x + minp.x + center_off, minp.y - 8, z + minp.z + center_off)
					for y = minp.y - 8, avg do
						if y > minp.y - 4 and (x == -1 or x == (cell_size * 2) or z == -1 or z == (cell_size * 2)) then
							data[ivm] = node['default:cobble']
						elseif ((x == 2 or x == 9) and z > 1 and z < 10) or ((z == 2 or z == 9) and x > 1 and x < 10) then
							data[ivm] = node['default:cobble']
						else
							local t
							if z < 2 then
								t = x
							elseif x > 9 then
								t = z + 11
							elseif z > 9 then
								t = 33 - x
							else
								t = 44 - z
							end
							t = math.floor(t / 44 * 10 * 2 + 0.5) / 2

							if x < 2 or x > 9 or z < 2 or z > 9 then
								if math.floor((y - minp.y) % 10 * 2 + 0.5) / 2 == t then
									data[ivm] = node['stairs:slab_cobble']
								elseif math.floor((y - minp.y) % 10 * 2 + 0.5) / 2 == t - 0.5 then
									data[ivm] = node['default:cobble']
								else
									data[ivm] = node['air']
								end
							end
						end

						ivm = ivm + area.ystride
					end
				end
			end
		end

		return true, true
	end

	if minp_in.y > 0 then
		return
	end

	local minp = table.copy(minp_in)
	minp.x = minp.x + border
	minp.z = minp.z + border
	local maxp = table.copy(maxp_in)
	maxp.x = maxp.x - border
	maxp.z = maxp.z - border
	center_off = center_off - border
	local level = math.min(6, math.ceil(maxp.y / math.floor(max_depth / -6)))
	local inner_floor = node['fun_caves:dungeon_floor_1']
	local outer_wall = node['fun_caves:dungeon_wall_2']
	local inner_wall = node['fun_caves:dungeon_wall_1']
	local treasure_count = 0
	local leave_alone = {}
	leave_alone[node['default:cobble']] = true
	leave_alone[node['stairs:stair_cobble']] = true
	leave_alone[node['stairs:slab_cobble']] = true
	leave_alone['stairway'] = true

	for z = minp.z - 1, maxp.z + 1 do
		for y = minp.y, maxp.y + 1 do
			local ivm = area:index(minp.x - 1, y, z)
			for x = minp.x - 1, maxp.x + 1 do
				local centered_out = (z >= minp.z + center_off - 1 and z <= maxp.z - center_off + 1 and x >= minp.x + center_off - 1 and x <= maxp.x - center_off + 1)
				local centered_in = (z >= minp.z + center_off and z <= maxp.z - center_off and x >= minp.x + center_off and x <= maxp.x - center_off)
				if y > maxp.y - dead_space then
					if centered_out and (x == minp.x + center_off - 1 or x == maxp.x - center_off + 1 or z == minp.z + center_off - 1 or z == maxp.z - center_off + 1) then
						data[ivm] = node['fun_caves:dungeon_wall_1']
					elseif not centered_out and y <= maxp.y then
						data[ivm] = node['default:stone']
					elseif y <= maxp.y and not leave_alone[data[ivm]] then
						data[ivm] = node['air']
					end
				elseif x == minp.x - 1 or x == maxp.x + 1 or z == minp.z - 1 or z == maxp.z + 1 then
					data[ivm] = node['fun_caves:dungeon_wall_1']
				elseif (y == minp.y or y == maxp.y - dead_space) and not centered_in then
					data[ivm] = node['fun_caves:dungeon_floor_1']
				end
				ivm = ivm + 1
			end
		end
	end

	local content = {}
	for cx = 0, (cells - 1) do
		content[cx] = {}
		for cy = 0, (cells_y - 1) do
			content[cx][cy] = {}
			for cz = 0, (cells - 1) do
				if cy == (cells_y - 1) and (cz == 4 or cz == 5) and (cx == 4 or cx == 5) then
					content[cx][cy][cz] = 'room'
				elseif cy == 0 and (cz == 4 or cz == 5) and (cx == 4 or cx == 5) then
					content[cx][cy][cz] = 'room'
				else
					content[cx][cy][cz] = '4way'
				end
			end
		end
	end

	for cy = 0, (cells_y - 2) do
		local x, z = math.random(1,8), math.random(0,(cells - 1))
		while cy == (cells_y - 1) and (z == 4 or z == 5) and (x == 4 or x == 5) do
			x, z = math.random(1,8), math.random(0,(cells - 1))
		end

		content[x][cy][z] = 'stair1'
		content[x - 1][cy][z] = 'room'
		if cy < (cells_y - 1) then
			content[x][cy + 1][z] = 'room'
			content[x + 1][cy + 1][z] = 'room'
		end

		x, z = math.random(0,(cells - 1)), math.random(1,8)
		while cy == (cells_y - 1) and (z == 4 or z == 5) and (x == 4 or x == 5) do
			x, z = math.random(0,(cells - 1)), math.random(1,8)
		end
		content[x][cy][z] = 'stair0'
		content[x][cy][z - 1] = 'room'
		if cy < (cells_y - 1) then
			content[x][cy + 1][z] = 'room'
			content[x][cy + 1][z + 1] = 'room'
		end
	end

	for cx = 0, (cells - 1) do
		for cy = 0, (cells_y - 1) do
			for cz = 0, (cells - 1) do
				if content[cx][cy][cz] == '4way' and math.random(2) == 1 then
					content[cx][cy][cz] = 'room'
				end
			end
		end
	end

	for cz = 0, (cells - 1) do
		local oz = minp.z + cz * cell_size
		for cy = 0, (cells_y - 1) do
			local oy = minp.y + cy * cell_size
			for cx = 0, (cells - 1) do
				local ox = minp.x + cx * cell_size
				local centered_in = ((cx == 4 or cx == 5) and (cz == 4 or cz == 5))

				if content[cx][cy][cz] == 'stair0' then
					for rz = 0, cell_size do
						for ry = 0, 9 do
							local ivm = area:index(ox, oy + ry, oz + rz)

							for rx = 0, (cell_size - 1) do
								if ry == rz + 1 and (rx == 2 or rx == 3) and (cy == (cells_y - 1) or rz < cell_size) then
									data[ivm] = node['stairs:stair_cobble']
									p2data[ivm] = 0
								elseif (ry >= rz + 1 and ry <= rz + 5) and (rx == 2 or rx == 3) then
									data[ivm] = 'stairway'
								elseif ry == rz and (rx == 2 or rx == 3) then
									data[ivm] = node['fun_caves:dungeon_floor_1']
								elseif rz < cell_size and ry == 0 then
									data[ivm] = node['fun_caves:dungeon_floor_1']
								elseif ry < cell_size and rz < cell_size then
									data[ivm] = node['fun_caves:dungeon_wall_1']
								end

								ivm = ivm + 1
							end
						end
					end
				elseif content[cx][cy][cz] == 'stair1' then
					for rz = 0, (cell_size - 1) do
						for ry = 0, 9 do
							local ivm = area:index(ox, oy + ry, oz + rz)

							for rx = 0, cell_size do
								if ry == rx + 1 and (rz == 2 or rz == 3) and (cy == (cells_y - 1) or rx < cell_size) then
									data[ivm] = node['stairs:stair_cobble']
									p2data[ivm] = 1
								elseif (ry >= rx + 1 and ry <= rx + 5) and (rz == 2 or rz == 3) then
									data[ivm] = 'stairway'
								elseif ry == rx and (rz == 2 or rz == 3) then
									data[ivm] = node['fun_caves:dungeon_floor_1']
								elseif rx < cell_size and ry == 0 then
									data[ivm] = node['fun_caves:dungeon_floor_1']
								elseif ry < cell_size and rx < cell_size then
									data[ivm] = node['fun_caves:dungeon_wall_1']
								end

								ivm = ivm + 1
							end
						end
					end
				else
					for rz = 0, (cell_size - 1) do
						for ry = 0, (cell_size - 1) do
							local ivm = area:index(ox, oy + ry, oz + rz)

							for rx = 0, (cell_size - 1) do
								if not leave_alone[data[ivm]] then
									if ry == 0 and (cy > 0 or not centered_in) then
										if content[cx][cy][cz] == 'room' then
											local r = math.random(5000)
											if r == 1 then
												data[ivm] = node['fun_caves:stone_with_gold_trap']
											elseif r == 2 then
												data[ivm] = node['fun_caves:stone_with_coal_trap']
											elseif r == 3 then
												data[ivm] = node['fun_caves:stone_with_iron_trap']
											elseif r == 4 then
												data[ivm] = node['fun_caves:stone_with_diamond_trap']
											else
												data[ivm] = node['fun_caves:dungeon_floor_1']
											end
										else
											data[ivm] = node['fun_caves:dungeon_floor_2']
										end
									elseif ry == (cell_size - 1) and (cy < (cells_y - 1) or not centered_in) then
										data[ivm] = node['fun_caves:dungeon_floor_2']
									elseif content[cx][cy][cz] == 'room' then
										data[ivm] = node['air']
									elseif content[cx][cy][cz] == '4way' and ry <= 2 and (rz == 2 or rz == 3 or rx == 2 or rx == 3) and (ox + rx >= minp.x + 2 and ox + rx <= maxp.x - 2 and oz + rz >= minp.z + 2 and oz + rz <= maxp.z - 2) then
										data[ivm] = node['air']
									elseif ry > 0 and content[cx][cy][cz] == '4way' then
										data[ivm] = node['fun_caves:dungeon_wall_1']
									end
								end

								ivm = ivm + 1
							end
						end
					end
				end
			end
		end
	end

	for i = 0, #data do
		if data[i] == 'stairway' then
			data[i] = node['air']
		end
	end

	return true, true, true
end