--!native
--!optimize 2

local RunService = game:GetService("RunService")

if RunService:IsServer() then
	error("ClientState can only be required on the client")
end

local Players = game:GetService("Players")
local ReplicatedStorage = game:GetService("ReplicatedStorage")

local Replica = require(ReplicatedStorage.Packages.replica)

local ClientState = {}

local HOTBAR_SIZE = 10

local localPlayer = Players.LocalPlayer
local replicaForPlayer = nil
local changed = Instance.new("BindableEvent")

local function fireChanged()
	changed:Fire()
end

local function onReplicaNew(replica)
	local tags = replica.Tags or {}
	if tags.UserId ~= localPlayer.UserId and tags.Player ~= localPlayer then
		return
	end

	replicaForPlayer = replica
	replica:OnChange(fireChanged)
	fireChanged()
end

Replica.OnNew("ClientState", onReplicaNew)
Replica.RequestData()

function ClientState:IsReady(): boolean
	return replicaForPlayer ~= nil
end

function ClientState:GetReplica()
	return replicaForPlayer
end

function ClientState:GetSelectedSlot(): number?
	if not replicaForPlayer then
		return nil
	end
	return replicaForPlayer.Data.selectedSlot
end

local function getInventory()
	return replicaForPlayer and replicaForPlayer.Data.inventory or nil
end

function ClientState:GetItemInfo(blockId: any)
	if not replicaForPlayer or not blockId then
		return nil
	end
	local inv = getInventory()
	local entry = inv and inv[tostring(blockId)]
	if not entry then
		return nil
	end

	return {
		id = tostring(blockId),
		name = entry.name or tostring(blockId),
		count = entry.count,
	}
end

function ClientState:GetHotbarSlots(): {string}
	if not replicaForPlayer then
		local slots = table.create(HOTBAR_SIZE)
		for i = 1, HOTBAR_SIZE do
			slots[i] = ""
		end
		return slots
	end

	return replicaForPlayer.Data.hotbar or {}
end

function ClientState:GetSlotInfo(slot: number)
	if not replicaForPlayer then
		return nil
	end
	local hotbar = replicaForPlayer.Data.hotbar
	if not hotbar then
		return nil
	end
	local id = hotbar[slot]
	if not id then
		return nil
	end
	return ClientState:GetItemInfo(id)
end

function ClientState:GetSelectedBlock()
	if not replicaForPlayer then
		return nil
	end
	local slot = ClientState:GetSelectedSlot()
	if not slot then
		return nil
	end
	return ClientState:GetSlotInfo(slot)
end

function ClientState:SetSelectedSlot(slot: number)
	if not replicaForPlayer then
		return
	end
	local hotbar = replicaForPlayer.Data.hotbar
	if not hotbar then
		return
	end
	if slot and slot >= 1 and slot <= HOTBAR_SIZE then
		replicaForPlayer:FireServer("SelectHotbarSlot", slot)
	end
end

ClientState.Changed = changed.Event

return ClientState