local function register_teleport(name, def)
	local function teleport_update_particles(pos, pname)
		local tm = math.random(10, 50) / 10
		minetest.add_particlespawner({
			amount = tm * 3,
			time = tm,
			minpos = {x = pos.x - 7/16, y = pos.y - 5/16, z = pos.z - 7/16},
			maxpos = {x = pos.x + 7/16, y = pos.y - 5/16, z = pos.z + 7/16},
			minvel = vector.new(-1, 2, -1),
			maxvel = vector.new(1, 5, 1),
			minacc = vector.new(0, -9.81, 0),
			maxacc = vector.new(0, -9.81, 0),
			--collisiondetection = true,
			--collision_removal = true,
			texture = def.tiles[1],
			playername = pname,
		})
		minetest.get_node_timer(pos):start(tm)
	end

	def.drawtype = "nodebox"
	def.node_box = {
		type = "fixed",
		fixed = {{-7/16, -1/2, -7/16, 7/16, -7/16, 7/16}},
	}
	def.paramtype = "light"
	def.groups = def.groups or {}
	def.sounds = def.sounds or sounds.metal
	def.on_construct = function(pos)
		teleport_update_particles(pos, nil)
	end
	def.on_timer = function(pos)
		teleport_update_particles(pos, nil)
	end
	def.after_box_construct = function(pos)
		teleport_update_particles(pos, nil)
	end

	minetest.register_node(name, def)
end

local context = {}

local function series_progress_reset(player, id)
	-- show a formspec to the user where they can explicitly reset
	-- series progress, and explain why they might not want to do so

	local name = player:get_player_name()
	context[name] = id

	minetest.show_formspec(name, "series:reset",
		"size[10,7]" ..
		"textlist[0.5,0.5;8.7,4.5;restettext;You have already completed this series.,," ..
		"If you want\\, you can reset your progress for this series," ..
		"and start it again from the start.,," ..
		"Or\\, you can wait for more boxes to get added to this," ..
		"series later\\, and come back regularly to check if that," ..
		"has happened.;0;0]" ..
		"button[0.6,5.5;4.4,1.5;btn_cancel;I'll come back later]" ..
		"button[5.0,5.5;4.4,1.5;btn_reset;Reset progress]"
	)
end

minetest.register_on_player_receive_fields(function(player, formname, fields)
	if formname ~= "series:reset" then
		return false
	end

	local name = player:get_player_name()
	minetest.close_formspec(name, "")

	if not context[name] then
		minetest.log("error", name .. " sends invalid formspec data")
		return true
	end

	if not fields.btn_reset then
		return true
	end

	-- reset series progress
	local id = context[name]
	local pmeta = db.player_get_meta(name)
	pmeta.series_progress[id] = nil
	db.player_set_meta(name, pmeta)

	minetest.chat_send_player(player:get_player_name(),
		"Reset progress for series " .. id)

	return true
end)

register_teleport("boxes:enter_teleport", {
	description = "Enter teleport",
	tiles = {"diamond.png"},
	on_walk_over = function(pos, node, player)
		local meta = minetest.get_meta(pos)
		local id = meta:get_int("box")
		if meta:get_int("is_series") == 1 then
			local smeta = db.series_get_meta(id)
			if not smeta then
				return
			end
			if not boxes.next_series(player, id, true) then
				--nudge player back off the teleport
				local dir = player:get_look_dir()
				dir.y = 0
				player:setpos(vector.subtract(pos, vector.normalize(dir)))
				series_progress_reset(player, id)
			end

			return
		end
		local bmeta = db.box_get_meta(id)
		if bmeta.type ~= db.BOX_TYPE then
			return
		end
		boxes.open_box(player, {0, id, 1})
	end,
	on_punch = function(pos, node, puncher, pointed_thing)
		if not puncher or not minetest.check_player_privs(puncher, "server") then
			return
		end
		local meta = minetest.get_meta(pos)
		if puncher:get_player_control().sneak then
			local is_series = meta:get_int("is_series")
			meta:set_int("is_series", 1 - is_series)
			minetest.chat_send_player(puncher:get_player_name(), "Destination is" ..
					((is_series == 0) and " " or " not ") .. "a series")
			return
		end
		local id = meta:get_int("box")
		local newid = id + 1
		if not db.box_exists(newid) then
			newid = 0
		end
		meta:set_int("box", newid)
		minetest.chat_send_player(puncher:get_player_name(), "Destination set to " .. newid)
	end,
	on_rightclick = function(pos, node, puncher, pointed_thing)
		if not puncher or not minetest.check_player_privs(puncher, "server") then
			return
		end
		local meta = minetest.get_meta(pos)
		local id = meta:get_int("box")
		local newid = id - 1
		if not db.box_exists(newid) then
			newid = db.get_last_box_id()
		end
		meta:set_int("box", newid)
		minetest.chat_send_player(puncher:get_player_name(), "Destination set to " .. newid)
	end,
})

register_teleport("boxes:exit_teleport", {
	description = "Exit teleport",
	tiles = {"diamond.png"},
	on_walk_over = function(pos, node, player)
		local name = player:get_player_name()
		if not boxes.players_in_boxes[name] then
			return
		end
		local bx = boxes.players_in_boxes[name]
		local stars = 0
		for _, p in ipairs(bx.star_positions) do
			local star_node = minetest.get_node(p)
			local nodedef = minetest.registered_nodes[star_node.name]
			if nodedef and nodedef.groups and nodedef.groups.star and nodedef.groups.star > 0 then
				stars = stars + 1
			end
		end
		local icons = {}
		for _, p in ipairs(bx.category_positions) do
			local sign_node = minetest.get_node(p)
			local nodedef = minetest.registered_nodes[sign_node.name]
			if nodedef and nodedef.groups and nodedef.groups.icon and nodedef.groups.icon > 0 and
			nodedef.icon_name and nodedef.icon_name ~= "nil" then
				icons[#icons + 1] = nodedef.icon_name
			end
		end
		local ic = ""
		for i, iname in ipairs(icons) do
			if i > 1 then
				ic = ic .. ", "
			end
			ic = ic .. iname
		end
		--minetest.chat_send_all("Player " .. name .. " exited box " .. tostring(bx.box_id) ..
		--		", rating it with " .. tostring(stars) .. " stars and icons {" .. ic .. "}")

		local sid = boxes.players_in_boxes[name].in_series
		boxes.close_box(player)
		if sid then
			boxes.next_series(player, sid)
		else
			players.return_to_lobby(player)
		end
	end,
})

register_teleport("boxes:lobby_teleport", {
	description = "Lobby teleport",
	tiles = {"gold.png"},
	on_walk_over = function(pos, node, player)
		local name = player:get_player_name()
		if not boxes.players_in_boxes[name] then
			return
		end
		boxes.close_box(player)
		players.return_to_lobby(player)
	end,
})

local get_boxes = function(name)
	local is_admin = minetest.check_player_privs(name, "server")
	local boxes = {}
	for id = 0, db.get_last_box_id() do
		local meta = db.box_get_meta(id)
		if (meta.type == meta.type and meta.meta and
				meta.meta.builder and meta.meta.builder == name) or is_admin then
			table.insert(boxes, {id = id,
			                     name = meta.meta.box_name or "[Unnamed]",
			                     status = meta.meta.status,
			                     builder = meta.meta.builder})
		end
	end
	table.sort(boxes, function(box1, box2)
		return box1.status < box2.status or
			(box1.status == box2.status and box1.id > box2.id)
	end)

	return boxes
end

local get_sizes = function(player)
	--FIXME link to scoring and limit box sizes for novice builders
	return {20, 25, 30, 35, 40}
end

local do_creator_if = function(player)
	local name = player:get_player_name()
	if not context[name] then
		context[name] = {}
		context[name].boxes = get_boxes(name)
		context[name].sizes = get_sizes(name)
	end

	local counts = {
		accepted = 0,
		submitted = 0,
		editing = 0
		}

	local f =
		"size[12, 8]" ..
		"field_close_on_enter[input;false]" ..
		"textlist[0.4,0.5;7.2,7.3;boxes;"
	--list of boxes owned, or all in case of admin
	for i, v in ipairs(context[name].boxes) do
		if i > 1 then f = f .. "," end
		local text = ""
		if v.status == db.STATUS_SUBMITTED then
			text = "#FF8800"
			counts.submitted = counts.submitted + 1
		elseif v.status == db.STATUS_ACCEPTED then
			text = "#00FF00"
			counts.accepted = counts.accepted + 1
		else
			if v.builder ~= name then
				text = "#FFFFAA"
			end
			counts.editing = counts.editing + 1
		end
		text = text .. v.id .. " - " .. minetest.formspec_escape(v.name)
		if v.builder ~= name then
			text = text .. " (" .. minetest.formspec_escape(v.builder or "") .. ")"
		end
		f = f .. text
	end
	f = f .. "]"

	local limit = tonumber(player:get_attribute("box_create_limit") or "")
	if limit == 0 then
		limit = 3
	end
	if (minetest.check_player_privs(name, "create") and counts.editing + counts.submitted <= limit) or
	   minetest.check_player_privs(name, "server") then
		context[name].cancreate = true
		f = f .. "button[8.4,1;3.4,1;new;Create new]"
	else
		minetest.chat_send_player(name, "You have too many unfinished boxes. Box creation will " ..
			"become available again once your boxes get accepted.")
	end

	if context[name].box and context[name].box.status == db.STATUS_EDITING then
		f = f .. "button[8.4,3;3.4,1;submit;Submit]"
	elseif minetest.check_player_privs(name, "server") and context[name].box and
	       context[name].box.status == db.STATUS_SUBMITTED then
		f = f .. "button[8.4,3;3.4,1;reject;Reject]"
		f = f .. "button[8.4,4;3.4,1;accept;Accept]"
	elseif context[name].box and context[name].box.status == db.STATUS_SUBMITTED then
		f = f .. "button[8.4,3;3.4,1;retract;Retract]"
	end

	if not context[name].box or context[name].box.status == db.STATUS_EDITING then
		f = f .. "button[8.4,7;3.4,1;edit;Edit]"
	elseif minetest.check_player_privs(name, "server") then
		f = f .. "button[8.4,7;3.4,1;edit;Force edit]"
	end

	if context[name].box then
		f = f .. "button[8.4,6;3.4,1;play;Play]"
	end

	minetest.show_formspec(player:get_player_name(), "boxes:create", f)
end

local do_creator_size_if = function(player)
	local name = player:get_player_name()
	assert(context[name])

	local f =
		"size[6.2, 6]" ..
		"field_close_on_enter[input;false]" ..
		"textlist[0.4,0.5;5.2,4.3;sizes;"

	for i, v in ipairs(context[name].sizes) do
		if i > 1 then f = f .. "," end
		f = f .. tostring(v)
	end
	f = f ..
		"]" ..
		"button[0.4,5;5.4,1;create;Choose selected size]"

	minetest.show_formspec(player:get_player_name(), "boxes:create", f)

end

minetest.register_on_player_receive_fields(function(player, formname, fields)
	if formname ~= "boxes:create" then
		return false
	end
	local name = player:get_player_name()

	if fields.quit then
		return true
	end

	-- minimum required permissions
	if not minetest.check_player_privs(name, "create") and
	   not minetest.check_player_privs(name, "server") then
		minetest.log("error", name .. " sends invalid formspec data")
		context[name] = nil
		return true
	end

	if not context[name] then
		context[name] = {
			sizes = {},
			boxes = {},
		}
	end

	local meta = nil

	-- makes reading the code below a bit easier
	local function box_set_status(id, status)
		if not meta then
			meta = db.box_get_meta(id)
			assert(meta.meta)
		end
		meta.meta.status = status
		db.box_set_meta(id, meta)
	end

	local function box_get_status(id)
		if not meta then
			meta = db.box_get_meta(id)
			assert(meta.meta)
		end
		return meta.meta.status
	end

	local is_admin = minetest.check_player_privs(name, "server")

	-- sadly a function, because meta may be nil
	local function is_builder(id)
		if not meta then
			meta = db.box_get_meta(id)
			assert(meta.meta)
		end
		return meta.meta.builder == name
	end

	if fields.boxes and fields.boxes ~= "INV" then
		local s, _ = fields.boxes:gsub(".*:(.*)", "%1")
		--FIXME check for the validity of these events to avoid crash by malicious player with hacked client
		local n = tonumber(s, 10)
		if context[name].boxes[n] then
			context[name].box = context[name].boxes[n]
			do_creator_if(player)
		end
	elseif fields.play and context[name].box then
		local id = context[name].box.id
		if is_admin or box_get_status(id) == db.STATUS_ACCEPTED or is_builder(id) then
			minetest.chat_send_player(name, "Playing box " .. tostring(id))
			minetest.registered_chatcommands["enter"].func(name, tostring(id))
		else
			minetest.log("error", name .. " sends invalid formspec data")
		end
		minetest.close_formspec(name, "")
		context[name] = nil
	elseif fields.edit and context[name].box then
		local id = context[name].box.id
		if is_admin or (box_get_status(id) == db.STATUS_EDITING and is_builder(id)) then
			minetest.chat_send_player(name, "Editing box " .. tostring(id))
			minetest.registered_chatcommands["edite"].func(name, tostring(id))
		else
			minetest.log("error", name .. " sends invalid formspec data")
		end
		minetest.close_formspec(name, "")
		context[name] = nil
	elseif fields.submit and context[name].box then
		local id = context[name].box.id
		if is_admin or (box_get_status(id) == db.STATUS_EDITING and is_builder(id)) then
			minetest.chat_send_player(name, "Submitting box " .. tostring(id))
			minetest.log("action", name .. " submits box " .. tostring(id))
			box_set_status(id, db.STATUS_SUBMITTED)
		else
			minetest.log("error", name .. " sends invalid formspec data")
		end
		minetest.close_formspec(name, "")
		context[name] = nil
	elseif fields.accept and context[name].box then
		local id = context[name].box.id
		if is_admin and box_get_status(id) == db.STATUS_SUBMITTED then
			minetest.chat_send_player(name, "Accepting box " .. tostring(id))
			minetest.log("action", name .. " accepts box " .. tostring(id))
			box_set_status(id, db.STATUS_ACCEPTED)
		else
			minetest.log("error", name .. " sends invalid formspec data")
		end
		minetest.close_formspec(name, "")
		context[name] = nil
	elseif fields.retract and context[name].box then
		local id = context[name].box.id
		if is_builder(id) and box_get_status(id) == db.STATUS_SUBMITTED then
			minetest.log("action", name .. " retracts box " .. tostring(id))
			minetest.chat_send_player(name, "Retracted box " .. tostring(id))
			box_set_status(id, db.STATUS_EDITING)
		else
			minetest.log("error", name .. " sends invalid formspec data")
		end
		minetest.close_formspec(name, "")
		context[name] = nil
	elseif fields.reject and context[name].box then
		local id = context[name].box.id
		if is_admin and box_get_status(id) == db.STATUS_SUBMITTED then
			minetest.log("action", name .. " rejects box " .. tostring(id))
			minetest.chat_send_player(name, "Rejecting box " .. tostring(id))
			box_set_status(id, db.STATUS_EDITING)
		else
			minetest.log("error", name .. " sends invalid formspec data")
		end
		minetest.close_formspec(name, "")
		context[name] = nil
	elseif fields.new and context[name].cancreate then
		do_creator_size_if(player)
	elseif fields.sizes then
		local s, _ = fields.sizes:gsub(".*:(.*)", "%1")
		context[name].size = context[name].sizes[tonumber(s, 10)]
	elseif fields.create and context[name].size and context[name].cancreate then
		minetest.close_formspec(name, "")
		minetest.chat_send_player(name, "Creating a new box with size " .. context[name].size)
		minetest.log("action", name .. " creates a new box with size " .. context[name].size)
		boxes.make_new(player, context[name].size)
		context[name] = nil
	else
		minetest.log("error", name .. " sends invalid formspec data")
		context[name] = nil
	end
	return true
end)

register_teleport("boxes:creator_teleport", {
	description = "Creator teleport",
	tiles = {"emerald.png"},
	on_walk_over = function(pos, node, player)
		context[player:get_player_name()] = nil
		local dir = player:get_look_dir()
		dir.y = 0
		player:setpos(vector.subtract(pos, vector.normalize(dir)))
		do_creator_if(player)
	end,
})

minetest.register_node("boxes:nexus", {
	description = "Nexus",
	drawtype = "mesh",
	mesh = "nexus.obj",
	paramtype = "light",
	paramtype2 = "facedir",
	light_source = 6,
	tiles = {
		{
			name = "nexus.png",
			animation = {
				type = "vertical_frames",
				aspect_w = 48,
				aspect_h = 16,
				length = 6.25,
			}
		},
	},
	selection_box = {
		type = "fixed",
		fixed = {-3/8, -3/8, -3/8, 3/8, 3/8, 3/8},
	},
	collision_box = {
		type = "fixed",
		fixed = {-3/8, -3/8, -3/8, 3/8, 3/8, 3/8},
	},
	group = {node = 0, nexus = 1},
	node_placement_prediction = "",
	on_place = function(itemstack, placer, pointed_thing, param2)
		-- Can't be placed, will only trigger on_rightclick if defined
		if pointed_thing.type == "node" then
			local n = minetest.get_node(pointed_thing.under)
			local nn = n.name
			if minetest.registered_nodes[nn] and minetest.registered_nodes[nn].on_rightclick then
				return minetest.registered_nodes[nn].on_rightclick(pointed_thing.under, n,
						placer, itemstack, pointed_thing) or itemstack, false
			end
		end

		return itemstack
	end,
	groups = {not_in_creative_inventory = 1},
})

minetest.register_node("boxes:nexus_large", {
	description = "Nexus",
	drawtype = "mesh",
	mesh = "nexus.obj",
	paramtype = "light",
	paramtype2 = "facedir",
	visual_scale = 4.0,
	tiles = {
		{
			name = "nexus.png",
			animation = {
				type = "vertical_frames",
				aspect_w = 48,
				aspect_h = 16,
				length = 6.25,
			}
		},
	},
	selection_box = {
		type = "fixed",
		fixed = {-3/8, -3/8, -3/8, 3/8, 3/8, 3/8},
	},
	collision_box = {
		type = "fixed",
		fixed = {-3/8, -3/8, -3/8, 3/8, 3/8, 3/8},
	},
	group = {node = 0},
	on_construct = function(pos)
		-- flip after 2 cycles
		minetest.get_node_timer(pos):start(12.5)
	end,
	on_timer = function(pos, node)
		-- make it self-rotate randomly
		minetest.swap_node(pos, {name = "boxes:nexus_large", param2 = math.random(24) - 1})
	end,
	groups = {not_in_creative_inventory = 1},
})


minetest.register_craftitem("boxes:set_door", {
	description = "Place or move entry and exit doors\nEntry door must be on the west wall.\n" ..
		"Exit door must be on the east wall.",
	inventory_image = "set_door_tool.png",
	on_place = function(itemstack, placer, pointed_thing)
		if pointed_thing.type ~= "node" or not placer then
			return
		end

		local name = placer:get_player_name()
		local pos = pointed_thing.under
		if not boxes.players_editing_boxes[name] then
			return
		end
		local box = boxes.players_editing_boxes[name]
		local pos1
		local pos2
		local dir
		local wallnode = {name = "nodes:marbleb"}
		if pos.x == box.minp.x then
			if pos.y <= box.minp.y or pos.y >= box.maxp.y - 2
				or pos.z <= box.minp.z or pos.z >= box.maxp.z - 2
			then
				return
			end
			pos1 = pos
			pos2 = {x = pos.x, y = pos.y, z = pos.z + 1}
			dir = 3
			for y = box.entry.y, box.entry.y + 1 do
				for z = box.entry.z, box.entry.z + 1 do
					minetest.set_node({x = pos.x, y = y, z = z}, wallnode)
				end
			end
			box.entry = {x = pos.x, y = pos.y, z = pos.z}
		elseif pos.x == box.maxp.x then
			if pos.y <= box.minp.y or pos.y >= box.maxp.y - 2
				or pos.z <= box.minp.z + 1 or pos.z >= box.maxp.z - 1
			then
				return
			end
			pos1 = pos
			pos2 = {x = pos.x, y = pos.y, z = pos.z - 1}
			dir = 1
			for y = box.exit.y, box.exit.y + 1 do
				for z = box.exit.z, box.exit.z + 1 do
					minetest.set_node({x = pos.x, y = y, z = z}, wallnode)
				end
			end
			box.exit = {x = pos.x + 1, y = pos.y, z = pos.z - 1}
		else
			return
		end
		local door_name = "doors:door_steel"
		local state1 = 0
		local state2 = 2
		local meta1 = minetest.get_meta(pos1)
		local meta2 = minetest.get_meta(pos2)
		local above1 = vector.add(pos1, {x = 0, y = 1, z = 0})
		local above2 = vector.add(pos2, {x = 0, y = 1, z = 0})
		minetest.set_node(pos1, {name = door_name .. "_a", param2 = dir})
		minetest.set_node(above1, {name = "doors:hidden", param2 = dir})
		meta1:set_int("state", state1)
		meta1:set_string("doors_owner", "boxes:door owner")
		minetest.set_node(pos2, {name = door_name .. "_b", param2 = dir})
		minetest.set_node(above2, {name = "doors:hidden", param2 = (dir + 3) % 4})
		meta2:set_int("state", state2)
		meta2:set_string("doors_owner", "boxes:door owner")
	end,
})
frame.register("boxes:set_door")