from dataclasses import dataclass

@dataclass
class ModelParams:
    g: float = 9.81
    H: float = 1000.0
    rho: float = 1025.0
    f0: float = 1.0e-4
    beta: float = 2.0e-11
    y0: float = 0.0
    r: float = 0.0  # Rayleigh friction rate [1/s]
    linear: bool = True  # keep linear; advection can be added later via hooks
    Ah: float = 0.0   # OPTIONAL lateral viscosity [m^2/s]; 0 disables it
    Hmin_frac: float = 0.02  # min 2% of H
    Ucap: float = 0.0        # cap |u|,|v| when forming K (m/s); 0 disables
    qmax: float = 0.0       # OPTIONAL: cap |q|; 0 disables

