local S = minetest.get_translator("lzr_levels")

lzr_levels = {}

local ROOM_NODE = "lzr_core:wood"
local WINDOW_NODE = "lzr_decor:woodframed_glass"
local WINDOW_HEIGHT = 3
local WINDOW_DIST = 3

local current_level = nil

local level_data = {}
lzr_levels.LAST_LEVEL = 0

-- Mod storage for game progress
local mod_storage = minetest.get_mod_storage()

local flat_index_to_pos = function(index, size)
	local d = index-1
	local x = d % size.x
	local y = math.floor((d / size.x) % size.y)
	local z = math.floor((d / (size.x*size.y)) % size.z)
	return vector.new(x,y,z)
end

-- Read the level schematics to find out some metadata about them
-- and count the number of levels
local analyze_levels = function()
	local level_list_path = minetest.get_modpath("lzr_levels").."/data/level_data.csv"
	local level_list_file = io.open(level_list_path, "r")
	assert(level_list_file, "Could not load level_data.csv")
	
	for line in level_list_file:lines() do
		local matches = string.split(line, ",")
		assert(matches ~= nil, "Malformed level_data.csv")
		local filename = matches[1]
		local lname = matches[2]
		table.insert(level_data, {filename=filename, name=lname})
	end
	lzr_levels.LAST_LEVEL = #level_data

	-- Mark levels that contain at least 1 rotatable block
	for l=1, #level_data do
		local filename = level_data[l].filename
		local filepath = minetest.get_modpath("lzr_levels").."/schematics/"..filename
		local schem = minetest.read_schematic(filepath, {write_yslice_prob="none"})
		assert(schem, "Could not load level file: "..filename)
		level_data[l].contains_rotatable_block = false
		level_data[l].size = schem.size
		local size = level_data[l].size
		for d=1, #schem.data do
			local nodename = schem.data[d].name
			local is_rotatable = minetest.get_item_group(nodename, "rotatable") == 1
			if is_rotatable then
				level_data[l].contains_rotatable_block = true
			end
			if nodename == "lzr_teleporter:teleporter_off" then
				local start = flat_index_to_pos(d, size)
				start = vector.add(start, vector.new(0, 0.5, 0))
				level_data[l].start_pos = start
			end
		end
	end
end

local build_room = function(param)
	local pos = param.pos
	local psize = param.size
	local posses_border = {}
	local posses_window = {}
	local size = vector.add(psize, {x=1,y=1,z=1})
	for x=0,size.x do
	for z=0,size.z do
	for y=0,size.y do
		local offset = {x=x-1, y=y-1, z=z-1}
		if not ((x >= 1 and x < size.x) and
		(y >= 1 and y < size.y) and
		(z >= 1 and z < size.z)) then
			if y == WINDOW_HEIGHT and ((x >= 1 and x < size.x and x % WINDOW_DIST == 0) or (z >= 1 and z < size.z and z % WINDOW_DIST == 0)) then
				table.insert(posses_window, vector.add(pos, offset))
			else
				table.insert(posses_border, vector.add(pos, offset))
			end
		end
	end
	end
	end
	minetest.bulk_set_node(posses_border, {name=ROOM_NODE})
	minetest.bulk_set_node(posses_window, {name=WINDOW_NODE})
end

local get_singleplayer = function()
	return minetest.get_player_by_name("singleplayer")
end

local emerge_callback = function(blockpos, action, calls_remaining, param)
	minetest.log("verbose", "[lzr_levels] emerge_callback() ...")
	if action == minetest.EMERGE_ERRORED then
		minetest.log("error", "[lzr_levels] Room emerging error.")
	elseif action == minetest.EMERGE_CANCELLED then
		minetest.log("error", "[lzr_levels] Room emerging cancelled.")
	elseif calls_remaining == 0 and (action == minetest.EMERGE_GENERATED or action == minetest.EMERGE_FROM_DISK or action == minetest.EMERGE_FROM_MEMORY) then
		lzr_levels.clear_playfield(param.size)
		build_room(param)
		if param.level then
			local level_ok = lzr_levels.build_level(param.level)
			if not level_ok then
				minetest.log("error", "[lzr_levels] Room emerge callback done with error")
			else
				local player = get_singleplayer()
				if player then
					if param.spawn_pos then
						player:set_pos(param.spawn_pos)
					end
					if param.yaw then
						player:set_look_horizontal(param.yaw)
						player:set_look_vertical(0)
					end
					lzr_messages.show_message(player, lzr_levels.get_level_name(param.level), 3)
					minetest.sound_play({name = "lzr_levels_level_enter", gain = 1}, {to_player=player:get_player_name()}, true)
				end
				minetest.log("action", "[lzr_levels] Room emerge callback done")
			end
		end
	end
end

local prepare_room = function(pos, size, level, spawn_pos, yaw)
	minetest.emerge_area(pos, vector.add(pos, size), emerge_callback, {pos=pos, size=size, level=level, spawn_pos=spawn_pos, yaw=yaw})
end

function lzr_levels.clear_playfield(room_size)
	local posses_air = {}
	local posses_water = {}
	local size = lzr_globals.PLAYFIELD_SIZE
	for z=0, size.z do
	for y=0, size.y do
	for x=0, size.x do
		local pos = vector.new(x,y,z)
		pos = vector.add(pos, lzr_globals.PLAYFIELD_START)
		if pos.y <= lzr_globals.WATER_LEVEL and (x > room_size.x or z > room_size.z) then
			table.insert(posses_water, pos)
		else
			table.insert(posses_air, pos)
		end
	end
	end
	end
	minetest.bulk_set_node(posses_water, {name="lzr_core:water_source"})
	minetest.bulk_set_node(posses_air, {name="air"})
end

function lzr_levels.build_room(pos, size, level, spawn_pos, yaw)
	prepare_room(pos, size, level, spawn_pos, yaw)
end

function lzr_levels.prepare_and_build_level(level, spawn_pos, yaw)
	lzr_levels.build_room(lzr_globals.LEVEL_POS, level_data[level].size, level, spawn_pos, yaw)
end

function lzr_levels.build_level(level)
	local filepath = minetest.get_modpath("lzr_levels").."/schematics/"..level_data[level].filename
	local schem = minetest.place_schematic(lzr_globals.LEVEL_POS, filepath, "0", {}, true, "")
	if schem then
		-- Propagate lasers and check for insta-win
		lzr_laser.full_laser_update(lzr_globals.PLAYFIELD_START, lzr_globals.PLAYFIELD_END)
		local done = lzr_laser.check_level_won()
		if done and lzr_gamestate.get_state() ~= lzr_gamestate.EDITOR then
			lzr_levels.level_complete()
		end
	else
		minetest.log("error", "[lzr_levels] lzr_levels.build_level failed to build level")
	end
	return schem
end

local function clear_inventory(player)
	local inv = player:get_inventory()
	for i=1,inv:get_size("main") do
		inv:set_stack("main", i, "")
	end
end

local function reset_inventory(player, needs_rotate)
	clear_inventory(player)
	if needs_rotate then
		local inv = player:get_inventory()
		inv:add_item("main", "screwdriver2:screwdriver")
	end
end

function lzr_levels.start_level(level)
	current_level = level
	local player = get_singleplayer()
	local start_pos -- player start position, relative to level
	local size = level_data[level].size
	if level_data[level].start_pos then
		start_pos = level_data[level].start_pos
	else
		-- Fallback start pos
		start_pos = vector.new(math.floor(size.x/2), -0.5, math.floor(size.z/2))
	end
	local spawn_pos = vector.add(lzr_globals.LEVEL_POS, start_pos) -- absolute spawn position
	local yaw = 0
	if start_pos.z > size.z/2 then
		yaw = yaw + math.pi
	end
	lzr_levels.prepare_and_build_level(level, spawn_pos, yaw)
	local needs_rotate = level_data[current_level].contains_rotatable_block
	reset_inventory(player, needs_rotate)
	if lzr_gamestate.get_state() ~= lzr_gamestate.EDITOR then
		lzr_gamestate.set_state(lzr_gamestate.LEVEL)
	end
	minetest.log("action", "[lzr_levels] Starting level "..level)
end

function lzr_levels.clear_level_progress()
	mod_storage:set_string("lzr_levels:levels", "")
	minetest.log("action", "[lzr_levels] Level progress was cleared")
end

function lzr_levels.mark_level_as_complete(level)
	local levels = minetest.deserialize(mod_storage:get_string("lzr_levels:levels"))
	if not levels then
		levels = {}
	end
	levels[level] = true
	mod_storage:set_string("lzr_levels:levels", minetest.serialize(levels))
end

function lzr_levels.get_completed_levels()
	local levels = minetest.deserialize(mod_storage:get_string("lzr_levels:levels"))
	if not levels then
		levels = {}
	end
	return levels
end

function lzr_levels.level_complete()
	if lzr_gamestate.get_state() == lzr_gamestate.LEVEL_COMPLETE then
		return false
	end
	lzr_levels.mark_level_as_complete(current_level)
	local player = get_singleplayer()
	lzr_messages.show_message(player, S("@1 complete!", lzr_levels.get_level_name(current_level)), 3)
	minetest.log("action", "[lzr_levels] Level "..current_level.." completed")
	minetest.sound_play({name = "lzr_levels_level_complete", gain = 1}, {to_player=player:get_player_name()}, true)
	lzr_gamestate.set_state(lzr_gamestate.LEVEL_COMPLETE)
	minetest.after(3, function(completed_level)
		if lzr_gamestate.get_state() == lzr_gamestate.LEVEL_COMPLETE and current_level == completed_level then
			lzr_levels.next_level()
		end
	end, current_level)
end

function lzr_levels.next_level()
	local player = get_singleplayer()
	current_level = current_level + 1
	if current_level > lzr_levels.LAST_LEVEL then
		lzr_messages.show_message(player, S("Final level completed!"), 5)
		lzr_levels.leave_level()
	else
		lzr_levels.start_level(current_level)
	end
end

function lzr_levels.leave_level()
	local player = get_singleplayer()
	current_level = nil
	clear_inventory(player)
	player:set_pos(vector.add(lzr_globals.MENU_SHIP_POS, lzr_globals.MENU_SHIP_PLAYER_SPAWN_OFFSET))
	player:set_look_horizontal(0)
	player:set_look_vertical(0)
	lzr_gamestate.set_state(lzr_gamestate.MENU)
end

function lzr_levels.get_current_level()
	return current_level
end

function lzr_levels.get_level_name(level)
	local name = level_data[level].name
	if name then
		return level_data[level].name
	else
		return S("Level @1", level)
	end
end

function lzr_levels.restart_level()
	local state = lzr_gamestate.get_state()
	if state == lzr_gamestate.LEVEL or state == lzr_gamestate.EDITOR then
		lzr_levels.start_level(current_level)
		return true
	else
		return false
	end
end

minetest.register_chatcommand("restart", {
	privs = {},
	params = "",
	description = S("Restart current level"),
	func = function(name, param)
		local state = lzr_gamestate.get_state()
		if state == lzr_gamestate.LEVEL or state == lzr_gamestate.EDITOR then
			lzr_levels.restart_level()
			return true
		elseif state == lzr_gamestate.LEVEL_COMPLETE then
			return false, S("Can’t restart level right now.")
		else
			return false, S("Not playing in a level!")
		end
	end,
})

minetest.register_chatcommand("leave", {
	privs = {},
	params = "",
	description = S("Leave current level"),
	func = function(name, param)
		if lzr_gamestate.get_state() == lzr_gamestate.LEVEL or lzr_gamestate.get_state() == lzr_gamestate.LEVEL_COMPLETE then
			lzr_levels.leave_level(current_level)
			return true
		else
			return false, S("Not playing in a level!")
		end
	end,
})

minetest.register_chatcommand("reset_progress", {
	privs = {},
	params = "yes",
	description = S("Reset level progress"),
	func = function(name, param)
		if param == "yes" then
			lzr_levels.clear_level_progress()
			return true, S("Level progress resetted.")
		else
			return false, S("To reset level progress, use “/reset_progress yes”")
		end
	end,
})



lzr_gamestate.register_on_enter_state(function(state)
	if state == lzr_gamestate.LEVEL then
		local player = minetest.get_player_by_name("singleplayer")
		lzr_player.set_play_inventory(player)
		lzr_gui.set_play_gui(player)
		lzr_laser.full_laser_update(lzr_globals.PLAYFIELD_START, lzr_globals.PLAYFIELD_END)
	end
end)


analyze_levels()