local Entity = Entity

local DebugRendering = false
local DebugInfos = false
local DeletedEntities = {}

--#region Local functions
local GetActiveSlices = function()
    local slices = GetSurroundingSlices(currentSlice)
    table.insert(slices, currentSlice)

    return slices
end

local AttachToEntity = function(obj, to, params)
    local attachToObj = nil

    if not params.isUtilityNet then
        attachToObj = NetworkGetEntityFromNetworkId(to)
    else
        -- Ensure that the entity is fully ready
        if UtilityNet.DoesUNetIdExist(to) then
            while not UtilityNet.IsReady(to) do
                Citizen.Wait(1)
            end
        else
                warn("AttachToEntity: trying to attach "..obj.." to "..to.." but the destination netId doesnt exist")
        end

        attachToObj = UtilityNet.GetEntityFromUNetId(to)
    end

    if attachToObj then
        if DebugInfos then
            print("Attaching", obj.." ("..GetEntityArchetypeName(obj)..")", "with", tostring(attachToObj).." ("..GetEntityArchetypeName(attachToObj)..")")
        end
        AttachEntityToEntity(obj, attachToObj, params.bone, params.pos, params.rot, false, params.useSoftPinning, params.collision, true, params.rotationOrder, params.syncRot)
    else
        warn("AttachToEntity: trying to attach "..obj.." to "..to.." but the destination entity doesnt exist")
    end
end

local FindEntity = function(coords, radius, model, uNetId, maxAttempts)
    local attempts = 0
    local obj = 0
        
    while attempts < maxAttempts and not DoesEntityExist(obj) do
        obj = GetClosestObjectOfType(coords.xyz, radius or 5.0, model)
        attempts = attempts + 1
        Citizen.Wait(500)
    end

    if attempts >= maxAttempts and not DoesEntityExist(obj) then
        warn("Failed to find object to replace, model: "..model.." coords: "..coords.." uNetId:"..uNetId)
        return
    end

    return obj
end
--#endregion

--#region Rendering functions
local busyEntities = {}
local SetNetIdBeingBusy = function(uNetId, status)
    busyEntities[uNetId] = status and true or nil
end

local IsNetIdBusy = function(uNetId)
    return busyEntities[uNetId]
end

exports("IsNetIdBusy", IsNetIdBusy)
exports("IsNetIdCreating", IsNetIdBusy)

local UnrenderLocalEntity = function(uNetId)
    local entity = UtilityNet.GetEntityFromUNetId(uNetId)

    if DoesEntityExist(entity) then
        TriggerEvent("Utility:Net:OnUnrender", uNetId, entity, GetEntityModel(entity))

        Citizen.SetTimeout(1, function()
            if not DoesEntityExist(entity) then
                if DebugInfos then
                    warn("UnrenderLocalEntity: entity with uNetId: "..uNetId.." already unrendered, skipping this call")
                end
                return
            end
    
            local state = Entity(entity).state
    
            -- Remove state change handler (currently used only for attaching)
            if state.changeHandler then
                UtilityNet.RemoveStateBagChangeHandler(state.changeHandler)
                state.changeHandler = nil
            end
    
            if state.found then
                local model = GetEntityModel(entity)
    
                -- Show map object
                RemoveModelHide(GetEntityCoords(entity), 0.1, model)
            end
    
            if state.preserved then
                SetEntityAsNoLongerNeeded(entity)
            else
                DeleteEntity(entity)
            end
    
            state.rendered = false
            EntitiesStates[uNetId] = nil
            TriggerLatentServerEvent("Utility:Net:RemoveStateListener", 5120, uNetId)
        end)
    end

    LocalEntities[uNetId] = nil
end

local RenderLocalEntity = function(uNetId, entityData)
    if IsNetIdBusy(uNetId) then
        if DebugRendering then
            warn("RenderLocalEntity: entity with uNetId: "..uNetId.." is already being created, skipping this call")
        end
        return
    end

    SetNetIdBeingBusy(uNetId, true)

    local obj = 0
    local stateUtility = UtilityNet.State(uNetId)
    local entityData = entityData or UtilityNet.InternalFindFromNetId(uNetId)

    -- Exit if entity data is missing
    if not entityData then
        error("UpdateLocalEntity: entity with uNetId: "..tostring(uNetId).." cant be found")
        return false
    end

    -- Set local variable (for readability)
    local coords = entityData.coords
    local model = entityData.model
    local options = entityData.options

    if not options.replace then
        if not IsModelValid(model) then
            error("RenderLocalEntity: Model "..model.." is not valid, uNetId: "..uNetId)
        end

        local start = GetGameTimer()
        while not HasModelLoaded(model) do
            if (GetGameTimer() - start) > 5000 then
                error("RenderLocalEntity: Model "..model.." failed to load, uNetId: "..uNetId)
            end

            RequestModel(model)
            Citizen.Wait(1)
        end
    end

    Citizen.CreateThread(function()
        if options.replace then
            local _obj = FindEntity(coords, options.searchDistance, model, uNetId, 5)
    
            -- Skip object creation if not found
            if not DoesEntityExist(_obj) then
                SetNetIdBeingBusy(uNetId, false)
                return
            end
    
            -- Clone object (otherwise it will be deleted when the entity is unrendered and will not respawn properly)
            local coords = GetEntityCoords(_obj)
            local rotation = GetEntityRotation(_obj)
    
            local interior = GetInteriorFromEntity(_obj)
            local room = GetRoomKeyFromEntity(_obj)
    
            obj = CreateObject(model, coords, false, false, options.door)
            SetEntityCoords(obj, coords)
            SetEntityRotation(obj, rotation)
            
            if interior ~= 0 and room ~= 0 then
                ForceRoomForEntity(obj, interior, room)
            end
    
            Entity(obj).state.found = true
    
            -- Hide map object
            local distance = options.door and 1.5 or 0.1

            if options.door and interior ~= 0 then
                -- Doors inside interiors need to be deleted
                -- If not deleted the game will be recreate them every time the interior is reloaded (player exit and then re-enter)
                -- And so there will be 2 copies of the same door
                DeleteEntity(_obj)
            else
                CreateModelHideExcludingScriptObjects(coords, distance, model)
            end
        else
            obj = CreateObject(model, coords, false, false, options.door)
            SetEntityCoords(obj, coords) -- This is required to ignore the pivot
        end
        
        local state = Entity(obj).state
    
        -- "Disable" the entity
        SetEntityVisible(obj, false)
        SetEntityCollision(obj, false, false)
        
        if options.rotation then
            SetEntityRotation(obj, options.rotation)
        end

        -- Always listen for __attached changes (attach/detach)
        state.changeHandler = UtilityNet.AddStateBagChangeHandler(uNetId, function(key, value)
            -- Exit if entity is no longer valid
            if not DoesEntityExist(obj) then
                UtilityNet.RemoveStateBagChangeHandler(state.changeHandler)
                return
            end

            if key == "__attached" then
                if value then
                    --print("Attach")
                    AttachToEntity(obj, value.object, value.params)
                else
                    --print("Detach")
                    DetachEntity(obj, true, true)
                end
            end
        end)
    
        LocalEntities[uNetId] = {obj=obj, slice=entityData.slice}
    
        -- Fetch initial state
        ServerRequestEntityStates(uNetId)
    
        -- After state has been fetched, attach if needed
        if stateUtility.__attached then
            AttachToEntity(obj, stateUtility.__attached.object, stateUtility.__attached.params)
        end

        -- "Enable" the entity, this is done after the state has been fetched to avoid props doing strange stuffs
        SetEntityVisible(obj, true)
        SetEntityCollision(obj, true, true)
    
        TriggerEvent("Utility:Net:OnRender", uNetId, obj, model)
    
        state.rendered = true
        SetNetIdBeingBusy(uNetId, false)
    end)
end

local CanEntityBeRendered = function(uNetId, entityData, slices)
    -- Default values
    local entityData = entityData or UtilityNet.InternalFindFromNetId(uNetId)

    -- Exit if entity data is missing
    if not entityData then
        return false
    end

    -- Check if entity is within drawing slices (if provided)
    if slices and not slices[entityData.slice] then
        return false
    end

    local state = UtilityNet.State(uNetId)

    if DeletedEntities[uNetId] then
        return false
    end

    -- Render only if within render distance
    if not state.__attached then
        local coords = GetEntityCoords(PlayerPedId())
        local modelsRenderDistance = GlobalState.ModelsRenderDistance
        local renderDistance = modelsRenderDistance[entityData.model] or 50.0

        if #(entityData.coords - coords) > renderDistance then
            return false
        end
    end

    return true
end
--#endregion

StartUtilityNetRenderLoop = function()
    -- Wait for player full load
    local isLoading = false

    while not HasCollisionLoadedAroundEntity(player) or not NetworkIsPlayerActive(PlayerId()) do
        isLoading = true
        Citizen.Wait(100)
    end

    if isLoading then
        Citizen.Wait(1000)
    end

    Citizen.CreateThread(function()
        local lastNEntities = 0 -- Used for managing the speed of the loop based on the number of entities
        local lastSlice = currentSlice
        
        while true do
            DeletedEntities = {}
            local slices = GetActiveSlices()
            local start = GetGameTimer()

            local somethingRendered = false -- If something has been rendered, speed up the whole loop to avoid a ugly effect where everything loads slowly
            local nEntities = 0

            local sleep = (Config.UtilityNetDynamicUpdate - 700) / math.min(20, lastNEntities) -- threshold to allow a little bit of lag and split by number of entities

            -- Render/Unrender near slices entities
            UtilityNet.ForEachEntity(function(v)
                nEntities = nEntities + 1

                if not LocalEntities[v.id] and CanEntityBeRendered(v.id, v) then
                    local obj = UtilityNet.GetEntityFromUNetId(v.id) or 0
                    local state = Entity(obj).state or {}

                    if not state.rendered then
                        somethingRendered = true
                        if DebugRendering then
                            print("RenderLocalEntity", v.id, "Loop")
                        end

                        RenderLocalEntity(v.id, v)                        
                    end
                elseif LocalEntities[v.id] and not CanEntityBeRendered(v.id, v) then
                    somethingRendered = true
                    UnrenderLocalEntity(v.id)
                end

                local outOfTime = (GetGameTimer() - start) > Config.UtilityNetDynamicUpdate
                if not somethingRendered or outOfTime then
                    Citizen.Wait(sleep * (2/3))
                end
            end, slices)

            -- Unrender entities that are out of slice
            -- Run only if the slice has changed (so something can be out of the slice and need to be unrendered)
            if lastSlice ~= currentSlice then
                local entities = GlobalState.Entities

                for netId, data in pairs(LocalEntities) do
                    local entityData = entities[data.slice][netId]
                
                    if not CanEntityBeRendered(netId, entityData) then
                        UnrenderLocalEntity(netId)
                    end
    
                    Citizen.Wait(sleep * (1/3))
                end

                lastSlice = currentSlice
            end

            if DebugRendering then
                print("end", GetGameTimer() - start)
            end

            lastNEntities = nEntities
            Citizen.Wait(Config.UpdateCooldown)
        end
    end)
end

RegisterNetEvent("Utility:Net:RefreshModel", function(uNetId, model)
    local start = GetGameTimer()
    while not LocalEntities[uNetId] and (GetGameTimer() - start < 3000) do
        Citizen.Wait(1)
    end

    if LocalEntities[uNetId] then
        -- Wait for the entity to exist and be rendered (prevent missing model replace on instant model change)
        while not UtilityNet.IsReady(uNetId) or IsNetIdBusy(uNetId) do
            Citizen.Wait(100)
        end
        SetNetIdBeingBusy(uNetId, true)

        -- Preserve the old object so that it does not flash (delete and instantly re-render)
        local oldObj = LocalEntities[uNetId].obj
        local _state = Entity(oldObj).state
        _state.preserved = true

        UnrenderLocalEntity(uNetId)

        -- Tamper with the entity model and render again
        local entityData = UtilityNet.InternalFindFromNetId(uNetId)

        if not entityData then
            error("RefreshModel: entity with uNetId: "..tostring(uNetId).." cant be found")
            return
        end

        entityData.model = model

        SetNetIdBeingBusy(uNetId, false)
        RenderLocalEntity(uNetId, entityData)

        local time = GetGameTimer()
        -- Wait for the entity to exist and be rendered
        while not UtilityNet.IsReady(uNetId) do
            if GetGameTimer() - time > 3000 then
                break
            end

            Citizen.Wait(1)
        end

        -- Delete the old object after the new one is rendered (so that it does not flash)
        DeleteEntity(oldObj)
    end
end)

RegisterNetEvent("Utility:Net:RefreshCoords", function(uNetId, coords)
    local start = GetGameTimer()
    while not LocalEntities[uNetId] and (GetGameTimer() - start < 3000) do
        Citizen.Wait(1)
    end
    
    if LocalEntities[uNetId] then
        while not UtilityNet.IsReady(uNetId) or IsNetIdBusy(uNetId) do
            Citizen.Wait(100)
        end

        SetNetIdBeingBusy(uNetId, true)
        SetEntityCoords(LocalEntities[uNetId].obj, coords)
        SetNetIdBeingBusy(uNetId, false)
    end
end)

RegisterNetEvent("Utility:Net:RefreshRotation", function(uNetId, rotation)
    local start = GetGameTimer()
    while not LocalEntities[uNetId] and (GetGameTimer() - start < 3000) do
        Citizen.Wait(1)
    end

    if LocalEntities[uNetId] then
        while not UtilityNet.IsReady(uNetId) or IsNetIdBusy(uNetId) do
            Citizen.Wait(100)
        end

        SetNetIdBeingBusy(uNetId, true)
        SetEntityRotation(LocalEntities[uNetId].obj, rotation)
        SetNetIdBeingBusy(uNetId, false)
    end
end)

RegisterNetEvent("Utility:Net:EntityCreated", function(_callId, uNetId)
    local attempts = 0

    while not UtilityNet.DoesUNetIdExist(uNetId) do
        attempts = attempts + 1

        if attempts > 5 then
            if DebugRendering then
                error("EntityCreated", uNetId, "id not found after 10 attempts")
            end
            return
        end
        Citizen.Wait(100)
    end

    if CanEntityBeRendered(uNetId) then
        if DebugRendering then
            print("RenderLocalEntity", uNetId, "EntityCreated")
        end

        RenderLocalEntity(uNetId)
    end
end)

RegisterNetEvent("Utility:Net:RequestDeletion", function(uNetId)
    if LocalEntities[uNetId] then
        DeletedEntities[uNetId] = true
        UnrenderLocalEntity(uNetId)
    end
end)

Citizen.CreateThread(function()
    while DebugRendering do
        DrawText3Ds(GetEntityCoords(PlayerPedId()), "Rendering Requested Entities: ".. #busyEntities)
        Citizen.Wait(1)
    end
end)

-- Exports
UtilityNet.GetEntityFromUNetId = function(uNetId)
    return LocalEntities[uNetId]?.obj
end

UtilityNet.GetUNetIdFromEntity = function(entity)
    for k, v in pairs(LocalEntities) do
        if v.obj == entity then
            return k
        end
    end
end

exports("GetEntityFromUNetId", UtilityNet.GetEntityFromUNetId)
exports("GetUNetIdFromEntity", UtilityNet.GetUNetIdFromEntity)
exports("GetRenderedEntities", function() return LocalEntities end)