if not TowBarMod then TowBarMod = {} end
if not TowBarMod.Hook then TowBarMod.Hook = {} end

local TowBarTowMass = 200
local AutoReattachCooldownHours = 1 / 7200 -- 0.5 seconds
TowBarMod.Hook.lastAutoReattachAtByVehicle = TowBarMod.Hook.lastAutoReattachAtByVehicle or {}
local AutoReattachPlayerCooldownHours = 1 / 14400 -- 0.25 seconds
TowBarMod.Hook.lastAutoReattachAtByPlayer = TowBarMod.Hook.lastAutoReattachAtByPlayer or {}

local function isTowBarTowPair(towingVehicle, towedVehicle)
    if not towingVehicle or not towedVehicle then return false end

    local towingModData = towingVehicle:getModData()
    local towedModData = towedVehicle:getModData()
    if not towingModData or not towedModData then return false end

    if towingModData["isTowingByTowBar"] and towedModData["isTowingByTowBar"] and towedModData["towed"] then
        return true
    end

    -- Rejoin fallback: original towbar state on the towed vehicle is enough to reapply rigid spacing.
    if towedModData.towBarOriginalScriptName ~= nil then
        return true
    end

    return false
end

local function getTowBarItem(playerObj)
    if not playerObj then return nil end
    local inventory = playerObj:getInventory()
    if not inventory then return nil end
    return inventory:getItemFromTypeRecurse("TowBar.TowBar")
end

local function setTowBarModelVisible(vehicle, isVisible)
    if not vehicle then return end

    local part = vehicle:getPartById("towbar")
    if part == nil then return end

    for j = 0, 23 do
        part:setModelVisible("towbar" .. j, false)
    end

    if not isVisible then
        vehicle:doDamageOverlay()
        return
    end

    local script = vehicle:getScript()
    if not script then
        vehicle:doDamageOverlay()
        return
    end

    local scale = script:getModelScale()
    if scale >= 1.5 and scale <= 2 then
        local z = script:getPhysicsChassisShape():z()/2 - 0.1
        part:setModelVisible("towbar" .. math.floor((z*2/3 - 1)*10), true)
    end

    vehicle:doDamageOverlay()
end

function TowBarMod.Hook.setVehiclePostAttach(playerObj, towedVehicle)
    if not towedVehicle then return end

    local towedModData = towedVehicle:getModData()
    if towedModData and towedModData.towBarOriginalScriptName then
        towedVehicle:setScriptName(towedModData.towBarOriginalScriptName)
    end

    towedVehicle:setMass(TowBarTowMass)
    towedVehicle:setBrakingForce(0)
    towedVehicle:constraintChanged()
    towedVehicle:updateTotalMass()
end

function TowBarMod.Hook.performAttachTowBar(playerObj, towingVehicle, towedVehicle, attachmentA, attachmentB)
    if playerObj == nil or towingVehicle == nil or towedVehicle == nil then return end
    if #(TowBarMod.Utils.getHookTypeVariants(towingVehicle, towedVehicle, true)) == 0 then return end

    local towBarItem = getTowBarItem(playerObj)
    if towBarItem ~= nil then
        sendClientCommand(playerObj, "towbar", "consumeTowBar", { itemId = towBarItem:getID() })
    end
    playerObj:setPrimaryHandItem(nil)

    TowBarMod.Utils.updateAttachmentsForRigidTow(towingVehicle, towedVehicle, attachmentA, attachmentB)

    local towingModData = towingVehicle:getModData()
    local towedModData = towedVehicle:getModData()

    towedModData.towBarOriginalScriptName = towedVehicle:getScriptName()
    towedModData.towBarOriginalMass = towedVehicle:getMass()
    towedModData.towBarOriginalBrakingForce = towedVehicle:getBrakingForce()

    towingModData["isTowingByTowBar"] = true
    towedModData["isTowingByTowBar"] = true
    towedModData["towed"] = true
    towingVehicle:transmitModData()
    towedVehicle:transmitModData()

    setTowBarModelVisible(towedVehicle, true)

    -- Match the known-good rigid tow path: fake trailer + vanilla attach command.
    towedVehicle:setScriptName("notTowingA_Trailer")

    local args = {
        vehicleA = towingVehicle:getId(),
        vehicleB = towedVehicle:getId(),
        attachmentA = attachmentA,
        attachmentB = attachmentB
    }
    sendClientCommand(playerObj, "vehicle", "attachTrailer", args)
    ISTimedActionQueue.add(TowBarScheduleAction:new(playerObj, 10, TowBarMod.Hook.setVehiclePostAttach, towedVehicle))
end

function TowBarMod.Hook.performDetachTowBar(playerObj, towingVehicle, towedVehicle)
    if playerObj == nil or towingVehicle == nil or towedVehicle == nil then return end

    TowBarMod.Utils.updateAttachmentsOnDefaultValues(towingVehicle, towedVehicle)

    local args = { towingVehicle = towingVehicle:getId(), vehicle = towedVehicle:getId() }
    sendClientCommand(playerObj, "towbar", "detachTowBar", args)

    local towedModData = towedVehicle:getModData()
    if towedModData.towBarOriginalScriptName then
        towedVehicle:setScriptName(towedModData.towBarOriginalScriptName)
    end
    if towedModData.towBarOriginalMass ~= nil then
        towedVehicle:setMass(towedModData.towBarOriginalMass)
    end
    if towedModData.towBarOriginalBrakingForce ~= nil then
        towedVehicle:setBrakingForce(towedModData.towBarOriginalBrakingForce)
    end
    towedVehicle:constraintChanged()
    towedVehicle:updateTotalMass()

    sendClientCommand(playerObj, "towbar", "giveTowBar", { equipPrimary = true })

    local towingModData = towingVehicle:getModData()
    towingModData["isTowingByTowBar"] = false
    towedModData["isTowingByTowBar"] = false
    towedModData["towed"] = false
    towedModData.towBarOriginalScriptName = nil
    towedModData.towBarOriginalMass = nil
    towedModData.towBarOriginalBrakingForce = nil
    towingVehicle:transmitModData()
    towedVehicle:transmitModData()

    TowBarMod.Hook.lastAutoReattachAtByVehicle[towingVehicle:getId()] = nil

    setTowBarModelVisible(towedVehicle, false)
end

function TowBarMod.Hook.reattachTowBarFromDriverSeat(playerObj, towingVehicle)
    if not playerObj or not towingVehicle then return end
    if not towingVehicle:isDriver(playerObj) then return end

    local towedVehicle = towingVehicle:getVehicleTowing()
    if not towedVehicle then return end

    local towingModData = towingVehicle:getModData()
    local towedModData = towedVehicle:getModData()
    if not towingModData or not towedModData then return end
    if not isTowBarTowPair(towingVehicle, towedVehicle) then return end

    local attachmentA = towingVehicle:getTowAttachmentSelf() or "trailer"
    local attachmentB = towingVehicle:getTowAttachmentOther() or "trailerfront"
    if not towingVehicle:canAttachTrailer(towedVehicle, attachmentA, attachmentB) then
        if towingVehicle:canAttachTrailer(towedVehicle, "trailer", "trailerfront") then
            attachmentA = "trailer"
            attachmentB = "trailerfront"
        elseif towingVehicle:canAttachTrailer(towedVehicle, "trailerfront", "trailer") then
            attachmentA = "trailerfront"
            attachmentB = "trailer"
        end
    end

    TowBarMod.Utils.updateAttachmentsForRigidTow(towingVehicle, towedVehicle, attachmentA, attachmentB)

    towedModData.towBarOriginalScriptName = towedModData.towBarOriginalScriptName or towedVehicle:getScriptName()
    if towedModData.towBarOriginalMass == nil then
        towedModData.towBarOriginalMass = towedVehicle:getMass()
    end
    if towedModData.towBarOriginalBrakingForce == nil then
        towedModData.towBarOriginalBrakingForce = towedVehicle:getBrakingForce()
    end

    towingModData["isTowingByTowBar"] = true
    towedModData["isTowingByTowBar"] = true
    towedModData["towed"] = true
    towingVehicle:transmitModData()
    towedVehicle:transmitModData()

    setTowBarModelVisible(towedVehicle, true)
    towedVehicle:setScriptName("notTowingA_Trailer")

    local args = {
        vehicleA = towingVehicle:getId(),
        vehicleB = towedVehicle:getId(),
        attachmentA = attachmentA,
        attachmentB = attachmentB
    }
    sendClientCommand(playerObj, "vehicle", "attachTrailer", args)
    ISTimedActionQueue.add(TowBarScheduleAction:new(playerObj, 10, TowBarMod.Hook.setVehiclePostAttach, towedVehicle))
end

local function tryAutoReattachFromCharacter(character)
    if not character or not instanceof(character, "IsoPlayer") or not character:isLocalPlayer() then return end

    local playerObj = character
    local nowHours = getGameTime() and getGameTime():getWorldAgeHours() or 0
    local playerNum = playerObj:getPlayerNum()
    local lastPlayerHours = TowBarMod.Hook.lastAutoReattachAtByPlayer[playerNum]
    if lastPlayerHours and (nowHours - lastPlayerHours) < AutoReattachPlayerCooldownHours then
        return
    end

    local towingVehicle = playerObj:getVehicle()
    if not towingVehicle then return end
    if not towingVehicle:isDriver(playerObj) then return end
    local towedVehicle = towingVehicle:getVehicleTowing()
    if not towedVehicle then return end
    if not isTowBarTowPair(towingVehicle, towedVehicle) then return end

    local vehicleId = towingVehicle:getId()
    local lastHours = TowBarMod.Hook.lastAutoReattachAtByVehicle[vehicleId]
    if lastHours and (nowHours - lastHours) < AutoReattachCooldownHours then
        return
    end

    TowBarMod.Hook.lastAutoReattachAtByPlayer[playerNum] = nowHours
    TowBarMod.Hook.lastAutoReattachAtByVehicle[vehicleId] = nowHours
    TowBarMod.Hook.reattachTowBarFromDriverSeat(playerObj, towingVehicle)
end

function TowBarMod.Hook.OnEnterVehicle(character)
    tryAutoReattachFromCharacter(character)
end

function TowBarMod.Hook.OnSwitchVehicleSeat(character)
    tryAutoReattachFromCharacter(character)
end

function TowBarMod.Hook.attachByTowBarAction(playerObj, towingVehicle, towedVehicle)
    if playerObj == nil or towingVehicle == nil or towedVehicle == nil then return end

    local item = getTowBarItem(playerObj)
    if item == nil then return end
    if #(TowBarMod.Utils.getHookTypeVariants(towingVehicle, towedVehicle, true)) == 0 then return end

    local hookPoint = towedVehicle:getAttachmentWorldPos("trailerfront", TowBarMod.Utils.tempVector1)
    if hookPoint == nil then return end
    ISTimedActionQueue.add(TowBarCustomPathFind:pathToLocationF(playerObj, hookPoint:x(), hookPoint:y(), hookPoint:z()))

    if not playerObj:getInventory():contains("TowBar.TowBar") then
        ISTimedActionQueue.add(ISInventoryTransferAction:new(playerObj, item, item:getContainer(), playerObj:getInventory(), nil))
    end

    local storePrim = playerObj:getPrimaryHandItem()
    if storePrim == nil or storePrim ~= item then
        ISTimedActionQueue.add(ISEquipWeaponAction:new(playerObj, item, 12, true))
    end

    ISTimedActionQueue.add(TowBarHookVehicle:new(playerObj, 300, TowBarMod.Config.lowLevelAnimation))

    hookPoint = towingVehicle:getAttachmentWorldPos("trailer", TowBarMod.Utils.tempVector1)
    if hookPoint == nil then return end
    ISTimedActionQueue.add(TowBarCustomPathFind:pathToLocationF(playerObj, hookPoint:x(), hookPoint:y(), hookPoint:z()))

    ISTimedActionQueue.add(TowBarHookVehicle:new(
        playerObj,
        100,
        TowBarMod.Config.lowLevelAnimation,
        TowBarMod.Hook.performAttachTowBar,
        towingVehicle,
        towedVehicle,
        "trailer",
        "trailerfront"
    ))
end

function TowBarMod.Hook.deattachTowBarAction(playerObj, vehicle)
    local towingVehicle = vehicle
    local towedVehicle = vehicle and vehicle:getVehicleTowing() or nil
    if vehicle and vehicle:getVehicleTowedBy() then
        towingVehicle = vehicle:getVehicleTowedBy()
        towedVehicle = vehicle
    end
    if towingVehicle == nil or towedVehicle == nil then return end

    local localPoint = towingVehicle:getAttachmentLocalPos(towingVehicle:getTowAttachmentSelf(), TowBarMod.Utils.tempVector1)
    local shift = 0
    if towingVehicle:getModData()["isChangedTowedAttachment"] then
        shift = localPoint:z() > 0 and -1 or 1
    end
    local hookPoint = towingVehicle:getWorldPos(localPoint:x(), localPoint:y(), localPoint:z() + shift, TowBarMod.Utils.tempVector2)
    if hookPoint == nil then return end
    ISTimedActionQueue.add(TowBarCustomPathFind:pathToLocationF(playerObj, hookPoint:x(), hookPoint:y(), hookPoint:z()))

    local storePrim = playerObj:getPrimaryHandItem()
    if storePrim ~= nil then
        ISTimedActionQueue.add(ISUnequipAction:new(playerObj, storePrim, 12))
    end

    ISTimedActionQueue.add(TowBarHookVehicle:new(playerObj, 100, TowBarMod.Config.lowLevelAnimation))

    localPoint = towedVehicle:getAttachmentLocalPos(towedVehicle:getTowAttachmentSelf(), TowBarMod.Utils.tempVector1)
    shift = 0
    if towedVehicle:getModData()["isChangedTowedAttachment"] then
        shift = localPoint:z() > 0 and -1 or 1
    end
    hookPoint = towedVehicle:getWorldPos(localPoint:x(), localPoint:y(), localPoint:z() + shift, TowBarMod.Utils.tempVector2)
    if hookPoint == nil then return end
    ISTimedActionQueue.add(TowBarCustomPathFind:pathToLocationF(playerObj, hookPoint:x(), hookPoint:y(), hookPoint:z()))

    ISTimedActionQueue.add(TowBarHookVehicle:new(
        playerObj,
        300,
        TowBarMod.Config.lowLevelAnimation,
        TowBarMod.Hook.performDetachTowBar,
        towingVehicle,
        towedVehicle
    ))
end

function TowBarMod.Hook.OnSpawnVehicle(vehicle)
    if not vehicle then return end

    local modData = vehicle:getModData()
    if not (modData and modData["isTowingByTowBar"] and modData["towed"]) then
        return
    end

    -- Keep behavior consistent after load/rejoin for active towbar tows.
    vehicle:setScriptName("notTowingA_Trailer")

    local playerObj = getPlayer()
    if playerObj then
        ISTimedActionQueue.add(TowBarScheduleAction:new(playerObj, 10, TowBarMod.Hook.setVehiclePostAttach, vehicle))
    else
        TowBarMod.Hook.setVehiclePostAttach(nil, vehicle)
    end
    setTowBarModelVisible(vehicle, true)
end

Events.OnSpawnVehicleEnd.Add(TowBarMod.Hook.OnSpawnVehicle)
Events.OnEnterVehicle.Add(TowBarMod.Hook.OnEnterVehicle)
Events.OnSwitchVehicleSeat.Add(TowBarMod.Hook.OnSwitchVehicleSeat)