World = class("World")

-- The world is deliberately only a layout: rooms continue to own their puzzle
-- state.  Keeping the two separate lets the editor move a room without
-- rewriting its level file.
function World:initialize()
	self.width, self.height = 18, 18
	self.rooms = {}
	self.roomByName = {}
	self.previewCache = {}
	self.lastRoom = nil
	self:load()
end

function World:listRoomNames()
	local names = {}
	for _, file in ipairs(love.filesystem.getDirectoryItems("rooms")) do
		local name = file:match("^(.+)%.sav$")
		if name and name ~= "world" then table.insert(names, name) end
	end
	table.sort(names)
	return names
end

function World:load()
	local raw = readFromSource("rooms/world.sav")
	if not raw then return end
	local ok, save = pcall(TSerial.unpack, raw)
	if not ok or type(save) ~= "table" then return end
	self.lastRoom = save.lastRoom
	for _, room in ipairs(save.rooms or {}) do
		if room.name and self:isInBounds(room.x, room.y) then
			self:_putRoom(room.name, room.x, room.y)
		end
	end
end

function World:save()
	local rooms = {}
	for _, room in ipairs(self.rooms) do
		table.insert(rooms, { name = room.name, x = room.x, y = room.y })
	end
	return writeToSource("rooms/world.sav", TSerial.pack({ width = self.width, height = self.height, lastRoom = self.lastRoom, rooms = rooms }, nil, true))
end

function World:isInBounds(x, y)
	return x and y and x >= 1 and x <= self.width and y >= 1 and y <= self.height
end

function World:roomAt(x, y)
	for _, room in ipairs(self.rooms) do
		if room.x == x and room.y == y then return room.name end
	end
	return nil
end

function World:roomLocation(name)
	return self.roomByName[name]
end

function World:_putRoom(name, x, y)
	local existing = self.roomByName[name]
	if existing then
		for i = #self.rooms, 1, -1 do
			if self.rooms[i] == existing then table.remove(self.rooms, i) end
		end
	end
	for i = #self.rooms, 1, -1 do
		if self.rooms[i].x == x and self.rooms[i].y == y then
			self.roomByName[self.rooms[i].name] = nil
			table.remove(self.rooms, i)
		end
	end
	local room = { name = name, x = x, y = y }
	table.insert(self.rooms, room)
	self.roomByName[name] = room
	return room
end

function World:placeRoom(name, x, y)
	if not name or not self:isInBounds(x, y) then return false end
	self:_putRoom(name, x, y)
	return self:save()
end

function World:removeRoom(x, y)
	for i = #self.rooms, 1, -1 do
		local room = self.rooms[i]
		if room.x == x and room.y == y then
			self.roomByName[room.name] = nil
			table.remove(self.rooms, i)
			if self.lastRoom == room.name then self.lastRoom = nil end
			return self:save(), room.name
		end
	end
	return false
end

function World:renameRoom(oldName, newName)
	local room = self:roomLocation(oldName)
	if not room or oldName == newName then return false end
	self.roomByName[oldName] = nil
	room.name = newName
	self.roomByName[newName] = room
	if self.lastRoom == oldName then self.lastRoom = newName end
	self:invalidatePreview(oldName)
	self:invalidatePreview(newName)
	return self:save()
end

function World:setLastRoom(name)
	if name and self.lastRoom ~= name then
		self.lastRoom = name
		return self:save()
	end
	return true
end

function World:getNeighbor(name, exit)
	local room = self:roomLocation(name)
	if not room then return nil end
	local directions = {
		left = { x = -1, y = 0 }, right = { x = 1, y = 0 },
		top = { x = 0, y = -1 }, bottom = { x = 0, y = 1 },
	}
	local direction = directions[exit]
	if not direction then return nil end
	return self:roomAt(room.x + direction.x, room.y + direction.y)
end

function World:getCellFromMousePos(mouseX, mouseY)
	return math.floor(mouseX / (width / self.width)) + 1, math.floor(mouseY / (height / self.height)) + 1
end

function World:getRoomData(name)
	-- The current room is live: its preview reflects unsaved edits immediately.
	if currentRoom and currentRoom.name == name then return currentRoom:serialize() end
	if not self.previewCache[name] then
		local raw = readFromSource("rooms/" .. name .. ".sav")
		if not raw then return nil end
		local ok, room = pcall(TSerial.unpack, raw)
		if not ok then return nil end
		self.previewCache[name] = room
	end
	return self.previewCache[name]
end

function World:invalidatePreview(name)
	self.previewCache[name] = nil
end

function World:drawRoomPreview(name, x, y, size)
	local room = self:getRoomData(name)
	if not room then return end
	local scale = size / (gridWidth * 16)
	love.graphics.setScissor(x, y, size, size)
	for _, object in ipairs(room.objects or {}) do
		if object.class == "npc" then
			love.graphics.setColor(255, 255, 255, 255)
			love.graphics.print("?", x + (object.x - 1) * 16 * scale, y + (object.y - 1) * 16 * scale, 0, scale, scale)
		else
			local props = globalAssetProperties[object.class]
			if props and props.sprites then
				local colors
				if object.class == "door" then
					colors = object.color and { object.color } or { "red", "green", "blue" }
				else
					colors = { object.color }
				end
				for _, color in ipairs(colors) do
					local path = props.sprites[color]
					if path then
						love.graphics.setColor(gColor[color]:set())
						love.graphics.draw(loadSprite(path), x + (object.x - 1) * 16 * scale, y + (object.y - 1) * 16 * scale, 0, scale, scale)
					end
				end
			end
		end
	end
	love.graphics.setScissor()
end

function World:draw()
	local cell = width / self.width
	love.graphics.setColor(12, 12, 20, 255)
	love.graphics.rectangle("fill", 0, 0, width, height)
	for y = 1, self.height do
		for x = 1, self.width do
			local screenX, screenY = (x - 1) * cell, (y - 1) * cell
			local name = self:roomAt(x, y)
			if name then self:drawRoomPreview(name, screenX, screenY, cell) end
			love.graphics.setColor(name and 255 or 70, name and 255 or 70, name and 255 or 90, 255)
			love.graphics.rectangle("line", screenX, screenY, cell, cell)
		end
	end
end