PLOT = False
FFT = PLOT and False

import math
import io, os
if PLOT: import matplotlib.pyplot as plt
if FFT: import numpy as np

DATA_RATE = 1187.5

ratio = 4
sample_rate = DATA_RATE*ratio
print(f"{sample_rate=}")
if not sample_rate.is_integer(): raise ValueError("Need a even value")

PATH = os.path.dirname(os.path.abspath(__file__))

outc = io.open(f"{PATH}/src/waveforms.c", mode="w", encoding="utf8")
outh = io.open(f"{PATH}/src/waveforms.h", mode="w", encoding="utf8")

header = u"""
/* This file was automatically generated by "gen_wave.py".
   (C) 2014 Christophe Jacquet.
   (C) 2023 Anthony96922.
   (C) 2025 kuba201.
   Released under the GNU GPL v3 license.
*/

"""

outc.write(header)
outh.write(header)

def generate():
	t = [i / sample_rate for i in range(ratio)]
	out = [math.sin(2 * math.pi * DATA_RATE * time) for time in t]
	print(f"{len(out)=}")

	if PLOT:
		plt.plot(out*4, label="out")
		plt.legend()
		plt.axvline(x=len(out)*2, color='r', linestyle='--', label='center')
		plt.grid(True)
		plt.show()

	if FFT:
		N = len(out)
		fft_out = np.fft.fft(out)
		fft_freqs = np.fft.fftfreq(N, d=1/sample_rate)

		plt.figure(figsize=(10, 6))
		plt.plot(fft_freqs[:N//2], np.abs(fft_out)[:N//2])
		plt.xlim(0,DATA_RATE*2.5)
		plt.title("FFT of the waveform")
		plt.xlabel("Frequency (Hz)")
		plt.ylabel("Magnitude")
		plt.grid(True)
		plt.show()

	outc.write(u"float waveform_biphase[{size}] = {{{values}}};\n\n".format(
		values = u", ".join(map(str, out)),
		size = len(out)))

	outh.write(u"extern float waveform_biphase[{size}];\n".format(size=len(out)))

generate()

outc.close()
outh.close()