import numpy as np
from scipy import signal

from .config import BODE_MAX_MULTIPLIER, BODE_POINTS
from .schemas import BodeParams
from .validation import require_finite, validate_coefficients


def calculate_bode_response(params: BodeParams):
    fs_val = require_finite(params.fs, "fs")
    b_vals = validate_coefficients(params.b, "b")
    a_vals = validate_coefficients(params.a, "a")
    f_min = params.fs / 50000.0
    f_max = params.fs * BODE_MAX_MULTIPLIER
    f_eval = np.logspace(np.log10(f_min), np.log10(f_max), BODE_POINTS)

    _, h = signal.freqz(b_vals, a_vals, worN=f_eval, fs=fs_val)
    mag = 20 * np.log10(np.abs(h) + 1e-12)
    phase = np.angle(h, deg=True)

    return {
        "freq": f_eval.tolist(),
        "mag": mag.tolist(),
        "phase": phase.tolist(),
    }