Cart@ cart;

const double S_PI = 3.141592653589793;
const string EN_FT_STATIC_DR_0 = "ft_ac_dr_0";
const string EN_FT_STATIC_DR_1 = "ft_ac_dr_1";
const string EN_FTT_DYNAMIC_CART = "ftt_ac";
const string EN_FW_STATIC_STRUCTURE = "fw_ac_struc";
const string EN_IT_STORAGE = "it_tankstorage";
const string EN_MM_ON_STOP_IN_B = "mm_ac_onstop_b";
const string EN_PC_STATIC_DR_0_0 = "pc_ac_dr_0_0";
const string EN_PC_STATIC_DR_0_1 = "pc_ac_dr_0_1";
const string EN_PC_STATIC_DR_1_0 = "pc_ac_dr_1_0";
const string EN_PC_STATIC_DR_1_1 = "pc_ac_dr_1_1";


final class Cart
{
    private CBaseEntity@ m_ftDr0;
    private CBaseEntity@ m_ftDr1;
    private CBaseEntity@ m_fttDynamicCart;
    private CBaseEntity@ m_fwStaticStructure;
    private CBaseEntity@ m_pcDr0_0;
    private CBaseEntity@ m_pcDr0_1;
    private CBaseEntity@ m_pcDr1_0;
    private CBaseEntity@ m_pcDr1_1;
    private string m_sCartId;
    private Vector m_vRelOriginFtDr0;
    private Vector m_vRelOriginFtDr1;
    private Vector m_vRelOriginPcDr0_0;
    private Vector m_vRelOriginPcDr0_1;
    private Vector m_vRelOriginPcDr1_0;
    private Vector m_vRelOriginPcDr1_1;
    private Vector m_vStorage;

    Cart(const string& in sCartId) {
        m_sCartId = sCartId;

        @m_ftDr0 = g_EntityFuncs.FindEntityByTargetname(null, EN_FT_STATIC_DR_0);
        @m_ftDr1 = g_EntityFuncs.FindEntityByTargetname(null, EN_FT_STATIC_DR_1);
        @m_fttDynamicCart = g_EntityFuncs.FindEntityByTargetname(null, EN_FTT_DYNAMIC_CART);
        @m_fwStaticStructure = g_EntityFuncs.FindEntityByTargetname(null, EN_FW_STATIC_STRUCTURE);
        @m_pcDr0_0 = g_EntityFuncs.FindEntityByTargetname(null, EN_PC_STATIC_DR_0_0);
        @m_pcDr0_1 = g_EntityFuncs.FindEntityByTargetname(null, EN_PC_STATIC_DR_0_1);
        @m_pcDr1_0 = g_EntityFuncs.FindEntityByTargetname(null, EN_PC_STATIC_DR_1_0);
        @m_pcDr1_1 = g_EntityFuncs.FindEntityByTargetname(null, EN_PC_STATIC_DR_1_1);

        m_vRelOriginFtDr0 = m_ftDr0.GetOrigin().opSub(m_fwStaticStructure.GetOrigin());
        m_vRelOriginPcDr0_0 = m_pcDr0_0.GetOrigin().opSub(m_fwStaticStructure.GetOrigin());
        m_vRelOriginPcDr0_1 = m_pcDr0_1.GetOrigin().opSub(m_fwStaticStructure.GetOrigin());
        m_vRelOriginFtDr1 = m_ftDr1.GetOrigin().opSub(m_fwStaticStructure.GetOrigin());
        m_vRelOriginPcDr1_0 = m_pcDr1_0.GetOrigin().opSub(m_fwStaticStructure.GetOrigin());
        m_vRelOriginPcDr1_1 = m_pcDr1_1.GetOrigin().opSub(m_fwStaticStructure.GetOrigin());
        m_vStorage = g_EntityFuncs.FindEntityByTargetname(null, EN_IT_STORAGE).GetOrigin();
    }

    void SwapStaticForDyn() {
        m_fttDynamicCart.SetOrigin(m_fwStaticStructure.GetOrigin());

        m_ftDr0.SetOrigin(m_vStorage.opAdd(m_vRelOriginFtDr0));
        m_ftDr1.SetOrigin(m_vStorage.opAdd(m_vRelOriginFtDr1));
        m_pcDr0_0.SetOrigin(m_vStorage.opAdd(m_vRelOriginPcDr0_0));
        m_pcDr0_1.SetOrigin(m_vStorage.opAdd(m_vRelOriginPcDr0_1));
        m_pcDr1_0.SetOrigin(m_vStorage.opAdd(m_vRelOriginPcDr1_0));
        m_pcDr1_1.SetOrigin(m_vStorage.opAdd(m_vRelOriginPcDr1_1));
        m_fwStaticStructure.SetOrigin(m_vStorage);
    }

    void SwapDynForStatic() {
        // g_PlayerFuncs.ClientPrintAll(HUD_PRINTCONSOLE, m_fttDynamicCart.pev.angles.ToString());

        Vector rotatedRelOriginFtDr0 = RotatePosition(m_vRelOriginFtDr0, ToRad(m_fttDynamicCart.pev.angles.y));
        m_ftDr0.SetOrigin(m_fttDynamicCart.GetOrigin().opAdd(rotatedRelOriginFtDr0));
        m_ftDr0.pev.angles = m_fttDynamicCart.pev.angles;

        Vector rotatedRelOriginPcDr0_0 = RotatePosition(m_vRelOriginPcDr0_0, ToRad(m_fttDynamicCart.pev.angles.y));
        m_pcDr0_0.SetOrigin(m_fttDynamicCart.GetOrigin().opAdd(rotatedRelOriginPcDr0_0));

        Vector rotatedRelOriginPcDr0_1 = RotatePosition(m_vRelOriginPcDr0_1, ToRad(m_fttDynamicCart.pev.angles.y));
        m_pcDr0_1.SetOrigin(m_fttDynamicCart.GetOrigin().opAdd(rotatedRelOriginPcDr0_1));

        Vector rotatedRelOriginFtDr1 = RotatePosition(m_vRelOriginFtDr1, ToRad(m_fttDynamicCart.pev.angles.y));
        m_ftDr1.SetOrigin(m_fttDynamicCart.GetOrigin().opAdd(rotatedRelOriginFtDr1));
        m_ftDr1.pev.angles = m_fttDynamicCart.pev.angles;

        Vector rotatedRelOriginPcDr1_0 = RotatePosition(m_vRelOriginPcDr1_0, ToRad(m_fttDynamicCart.pev.angles.y));
        m_pcDr1_0.SetOrigin(m_fttDynamicCart.GetOrigin().opAdd(rotatedRelOriginPcDr1_0));

        Vector rotatedRelOriginPcDr1_1 = RotatePosition(m_vRelOriginPcDr1_1, ToRad(m_fttDynamicCart.pev.angles.y));
        m_pcDr1_1.SetOrigin(m_fttDynamicCart.GetOrigin().opAdd(rotatedRelOriginPcDr1_1));

        m_fwStaticStructure.SetOrigin(m_fttDynamicCart.GetOrigin());
        m_fwStaticStructure.pev.angles = m_fttDynamicCart.pev.angles;

        m_fttDynamicCart.SetOrigin(m_vStorage);
    }

    void WaitForTrainToStop(const string &in target)
    {
        // g_PlayerFuncs.ClientPrintAll(HUD_PRINTCONSOLE, string(massnCart.pev.speed) + "\n");
        if (m_fttDynamicCart.pev.speed == 0) {
            g_EntityFuncs.FireTargets(target, m_fttDynamicCart, m_fttDynamicCart, USE_ON);
        }
    }

    // @todo Make private
    double ToRad(const double &in degree) {
        return degree * S_PI / 180;
    }

    // @todo Make private
    Vector RotatePosition(Vector initialPosition, const double angle_rad) {
        return Vector(
            initialPosition.x * cos(angle_rad) - initialPosition.y * (-sin(angle_rad)),
            initialPosition.x * sin(angle_rad) + initialPosition.y * cos(angle_rad),
            initialPosition.z
        );
    }
}

/// @todo Optimise.
/// @todo Rename.
/// @todo Hard-coded values (entity names, minimum distance).
/// @todo Use tracing.
// void ManageCartCrash(CBaseEntity @pActivator)
// {
//     CBaseEntity@ ftt_train = g_EntityFuncs.FindEntityByTargetname(null, "ftt_train");
//     CBaseEntity@ ftt_massncart = g_EntityFuncs.FindEntityByTargetname(null, "ftt_cart_0");
//     Vector sub =  ftt_massncart.GetOrigin().opSub(ftt_train.GetOrigin());
//     if (abs(sub.x) < 90 && abs(sub.y) < 90 && abs(sub.z) < 90) {
//         g_EntityFuncs.FireTargets("mm_ftttraincrash", ftt_massncart, ftt_massncart, USE_ON);
//     }
// }