local QBCore = exports['qb-core']:GetCoreObject()
local loadedKayaks = {}
local currentTrailer = nil

-- Function to check if a model is a kayak
local function IsKayakModel(model)
    for _, kayakModel in ipairs(Config.KayakModels) do
        if GetHashKey(kayakModel) == model then
            return true
        end
    end
    return false
end

-- Function to get nearby kayak
local function GetNearbyKayak()
    local playerPed = PlayerPedId()
    local playerCoords = GetEntityCoords(playerPed)
    
    local kayak = nil
    local minDistance = Config.InteractionRange
    
    for _, entity in ipairs(GetGamePool('CVehicle')) do
        if IsKayakModel(GetEntityModel(entity)) then
            local distance = #(playerCoords - GetEntityCoords(entity))
            if distance < minDistance then
                minDistance = distance
                kayak = entity
            end
        end
    end
    
    return kayak
end

-- Function to get nearby trailer
local function GetNearbyTrailer()
    local playerPed = PlayerPedId()
    local playerCoords = GetEntityCoords(playerPed)
    
    local trailer = nil
    local minDistance = Config.InteractionRange
    
    for _, entity in ipairs(GetGamePool('CVehicle')) do
        if GetEntityModel(entity) == GetHashKey(Config.TrailerModel) then
            local distance = #(playerCoords - GetEntityCoords(entity))
            if distance < minDistance then
                minDistance = distance
                trailer = entity
            end
        end
    end
    
    return trailer
end

-- Function to load kayak onto trailer
local function LoadKayakOntoTrailer(trailer, kayak)
    if not trailer or not kayak then return end
    
    local trailerNetId = NetworkGetNetworkIdFromEntity(trailer)
    local kayakNetId = NetworkGetNetworkIdFromEntity(kayak)
    
    -- Check if trailer already has max kayaks
    if #loadedKayaks >= Config.MaxKayaks then
        QBCore.Functions.Notify("Trailer rack is already fully loaded with kayaks", "error")
        return
    end
    
    -- Add kayak to loaded kayaks
    table.insert(loadedKayaks, kayakNetId)
    
    -- Update kayak position on trailer
    local position = Config.KayakPositions[#loadedKayaks]
    local trailerCoords = GetEntityCoords(trailer)
    local trailerHeading = GetEntityHeading(trailer)
    
    -- Calculate world position based on trailer position and offset
    local kayakX = trailerCoords.x + (math.cos(math.rad(trailerHeading)) * position.x) - (math.sin(math.rad(trailerHeading)) * position.y)
    local kayakY = trailerCoords.y + (math.sin(math.rad(trailerHeading)) * position.x) + (math.cos(math.rad(trailerHeading)) * position.y)
    local kayakZ = trailerCoords.z + position.z
    local kayakHeading = trailerHeading + position.heading
    
    -- Set kayak position and attach to trailer
    SetEntityCoords(kayak, kayakX, kayakY, kayakZ, false, false, false, false)
    SetEntityHeading(kayak, kayakHeading)
    
    -- Attach kayak to trailer
    AttachEntityToEntity(kayak, trailer, 0, position.x, position.y, position.z, 0.0, 0.0, position.heading, true, false, true, false, 0, true)
    
    -- Display which rack position was loaded
    local side = #loadedKayaks <= 3 and "left" or "right"
    local level = (#loadedKayaks - 1) % 3 + 1
    local levelNames = {"bottom", "middle", "top"}
    
    QBCore.Functions.Notify("Kayak loaded onto " .. levelNames[level] .. " rack, " .. side .. " side", "success")
    
    -- Save current trailer
    currentTrailer = trailerNetId
    
    -- Sync with server
    TriggerServerEvent('kayak_trailer:syncLoadedKayaks', trailerNetId, loadedKayaks)
end

-- Function to unload kayak from trailer
local function UnloadKayakFromTrailer(trailer)
    if not trailer or #loadedKayaks == 0 then return end
    
    local trailerNetId = NetworkGetNetworkIdFromEntity(trailer)
    
    -- Get last kayak
    local kayakNetId = loadedKayaks[#loadedKayaks]
    local kayak = NetworkGetEntityFromNetworkId(kayakNetId)
    
    -- Get position info for notification
    local side = #loadedKayaks <= 3 and "left" or "right"
    local level = (#loadedKayaks - 1) % 3 + 1
    local levelNames = {"bottom", "middle", "top"}
    
    -- Remove from loaded kayaks
    table.remove(loadedKayaks, #loadedKayaks)
    
    -- Detach kayak from trailer
    DetachEntity(kayak, true, true)
    
    -- Place kayak behind trailer
    local trailerCoords = GetEntityCoords(trailer)
    local trailerHeading = GetEntityHeading(trailer)
    local offsetX = -3.0 -- 3 meters behind trailer
    
    local kayakX = trailerCoords.x - (math.cos(math.rad(trailerHeading)) * offsetX)
    local kayakY = trailerCoords.y - (math.sin(math.rad(trailerHeading)) * offsetX)
    local kayakZ = trailerCoords.z
    
    SetEntityCoords(kayak, kayakX, kayakY, kayakZ, false, false, false, false)
    SetEntityHeading(kayak, trailerHeading)
    
    QBCore.Functions.Notify("Kayak unloaded from " .. levelNames[level] .. " rack, " .. side .. " side", "success")
    
    -- Sync with server
    TriggerServerEvent('kayak_trailer:syncLoadedKayaks', trailerNetId, loadedKayaks)
end

-- Initialize qb-target
Citizen.CreateThread(function()
    -- Target for loading kayaks onto trailer
    exports['qb-target']:AddTargetModel(Config.TrailerModel, {
        options = {
            {
                type = "client",
                event = "kayak_trailer:loadKayak",
                icon = "fas fa-truck-loading",
                label = "Load Kayak to Rack",
                canInteract = function()
                    local kayak = GetNearbyKayak()
                    return kayak ~= nil and #loadedKayaks < Config.MaxKayaks
                end
            },
            {
                type = "client",
                event = "kayak_trailer:unloadKayak",
                icon = "fas fa-dolly",
                label = "Unload Kayak from Rack",
                canInteract = function()
                    return #loadedKayaks > 0
                end
            }
        },
        distance = Config.InteractionRange
    })
    
    -- Target for kayaks
    for _, model in ipairs(Config.KayakModels) do
        exports['qb-target']:AddTargetModel(model, {
            options = {
                {
                    type = "client",
                    event = "kayak_trailer:loadKayak",
                    icon = "fas fa-truck-loading",
                    label = "Load onto Trailer Rack",
                    canInteract = function()
                        local trailer = GetNearbyTrailer()
                        return trailer ~= nil and #loadedKayaks < Config.MaxKayaks
                    end
                }
            },
            distance = Config.InteractionRange
        })
    end
end)

-- Event handlers
RegisterNetEvent('kayak_trailer:loadKayak', function()
    local trailer = GetNearbyTrailer()
    local kayak = GetNearbyKayak()
    
    if trailer and kayak then
        LoadKayakOntoTrailer(trailer, kayak)
    else
        QBCore.Functions.Notify("No trailer or kayak nearby", "error")
    end
end)

RegisterNetEvent('kayak_trailer:unloadKayak', function()
    local trailer = GetNearbyTrailer()
    
    if trailer then
        UnloadKayakFromTrailer(trailer)
    else
        QBCore.Functions.Notify("No trailer nearby", "error")
    end
end)

-- Sync loaded kayaks from server
RegisterNetEvent('kayak_trailer:syncLoadedKayaksClient', function(trailerNetId, kayakList)
    if NetworkDoesNetworkIdExist(trailerNetId) then
        local trailer = NetworkGetEntityFromNetworkId(trailerNetId)
        
        -- Clear existing kayaks
        for _, kayakNetId in ipairs(loadedKayaks) do
            if NetworkDoesNetworkIdExist(kayakNetId) then
                local kayak = NetworkGetEntityFromNetworkId(kayakNetId)
                if DoesEntityExist(kayak) then
                    DetachEntity(kayak, true, true)
                end
            end
        end
        
        -- Update loaded kayaks
        loadedKayaks = kayakList
        
        -- Reattach kayaks
        for i, kayakNetId in ipairs(loadedKayaks) do
            if NetworkDoesNetworkIdExist(kayakNetId) then
                local kayak = NetworkGetEntityFromNetworkId(kayakNetId)
                if DoesEntityExist(kayak) then
                    local position = Config.KayakPositions[i]
                    AttachEntityToEntity(kayak, trailer, 0, position.x, position.y, position.z, 0.0, 0.0, position.heading, true, false, true, false, 0, true)
                end
            end
        end
        
        currentTrailer = trailerNetId
    end
end)