import numpy as np
import soundfile as sf

SAMPLE_RATE = 44100
DURATION = 1.2

def piano_key_frequency(n):
    return 2 ** ((n - 49) / 12) * 440.0

def generate_tone(n, frequency):
    samples = int(SAMPLE_RATE * DURATION)
    t = np.linspace(0, DURATION, samples, False)
    tone = np.zeros(samples)

    # Two slightly detuned strings per note (chorus)
    for detune in [-0.3, 0.3]:
        f = frequency * (1 + detune / 1200)

        # Rich harmonics with bright, metallic decay
        for h in range(1, 16):
            amp = 1.0 / (h ** 1.2)           # bright: harmonics stay loud
            decay = 5.0 + h * 1.5             # faster overall decay
            tone += amp * np.exp(-decay * t) * np.sin(2 * np.pi * f * h * t)

    # Sharp pluck-like attack (2 ms)
    tone *= np.minimum(t / 0.002, 1.0)

    # Fast exponential decay -- plucked string feel
    tone *= np.exp(-4.0 * t)

    # Pluck transient: bright click at the start (5 ms)
    click = np.random.randn(samples) * np.exp(-t / 0.003)
    tone += 0.08 * click

    peak = np.max(np.abs(tone))
    if peak > 0:
        tone *= 0.4 / peak
    return tone

for n in range(1, 89):
    f = piano_key_frequency(n)
    sf.write(f"piano_key_{n}.wav", generate_tone(n, f), SAMPLE_RATE)
    print(f"piano_key_{n}.wav ({f:.1f} Hz)")

print("Done.")