local failures = 0

local function expect(condition, message)
    if not condition then
        failures = failures + 1
        io.stderr:write("FAIL: " .. message .. "\n")
    end
end

local activeModIds = {}

getActivatedMods = function()
    return {
        contains = function(_, modId)
            return activeModIds[modId] == true
        end
    }
end

local function vehicle(fullName, modelScale)
    return {
        getScript = function()
            return {
                getFullName = function() return fullName end,
                getModelScale = function() return modelScale end
            }
        end
    }
end

local classifierPath = "42.20/media/lua/shared/TowBar/VehicleCompatibility.lua"
local loaded, loadError = pcall(dofile, classifierPath)
expect(loaded, "dual-mode classifier must load from " .. classifierPath .. ": " .. tostring(loadError))

local Compatibility = TowBarMod and TowBarMod.Compatibility
expect(Compatibility ~= nil, "classifier must expose TowBarMod.Compatibility")
expect(Compatibility and type(Compatibility.isKi5Vehicle) == "function",
    "classifier must expose isKi5Vehicle(vehicle)")

if Compatibility and type(Compatibility.isKi5Vehicle) == "function" then
    local function isKi5(fullName, modelScale)
        return Compatibility.isKi5Vehicle(vehicle(fullName, modelScale))
    end

    -- Positive contracts use exact mod IDs and exact script full names verified
    -- from the locally installed KI5 workshop items.
    activeModIds = { ["91range"] = true }
    expect(isKi5("Base.91range", 0.01), "active KI5 Range Rover must use KI5 mode")

    activeModIds = { ["87toyotaCorolla"] = true }
    expect(isKi5("Base.87toyotaCorollaAE92levin", 1.75),
        "active KI5 Corolla must use KI5 mode regardless of model scale")

    activeModIds = { ["76chevyKseries"] = true }
    expect(isKi5("Base.76chevyK30CCwrecker", 1.75),
        "active KI5 Chevrolet variant must use KI5 mode")

    -- Exact identity is intentional. Scale, name fragments, attachment shape,
    -- and an active mod ID by itself must never capture another vehicle.
    activeModIds = {}
    expect(not isKi5("Base.91range", 0.01),
        "a KI5-looking script without its exact active mod must use legacy mode")

    activeModIds = { ["91range"] = true }
    expect(not isKi5("Base.91rangeBurnt", 0.01),
        "a suffixed KI5 lookalike must use legacy mode")
    expect(not isKi5("Base.CarNormal", 0.01),
        "vanilla must not be classified by KI5-like model scale")
    expect(not isKi5("Base.SmallCar", 1.75),
        "vanilla must not be classified by legacy vanilla model scale")
    expect(not isKi5("Base.Chevalier_Rhino_TowTruck", 0.01),
        "a non-KI5 tow-truck mod must use legacy mode")

    activeModIds = { ["91range-copy"] = true }
    expect(not isKi5("Base.91range", 0.01),
        "a prefix or suffix match on mod ID must not enable KI5 mode")

    expect(not Compatibility.isKi5Vehicle(nil), "nil vehicle must safely use legacy mode")
    expect(not Compatibility.isKi5Vehicle({ getScript = function() return nil end }),
        "vehicle without a script must safely use legacy mode")
end

if failures > 0 then os.exit(1) end
print("PASS: exact KI5 dual-mode classifier")