#!/usr/bin/env python3
"""Generate crisp, pleasant retro/modern sound effects as 16-bit 44.1kHz mono WAVs."""
import math
import struct
import wave
from pathlib import Path

SAMPLE_RATE = 44100
OUT_DIR = Path(__file__).resolve().parent.parent / "assets" / "audio"
OUT_DIR.mkdir(parents=True, exist_ok=True)


def write_wav(filename: str, samples: list[float]):
    path = OUT_DIR / filename
    with wave.open(str(path), "w") as wav:
        wav.setnchannels(1)
        wav.setsampwidth(2)
        wav.setframerate(SAMPLE_RATE)
        raw = bytearray()
        for s in samples:
            val = max(-1.0, min(1.0, s))
            ival = int(val * 32767)
            raw.extend(struct.pack("<h", ival))
        wav.writeframes(raw)
    print(f"Generated {path} ({len(samples)} samples, {len(samples)/SAMPLE_RATE:.2f}s)")


def gen_bell():
    """Resonant brass bell chime with multiple harmonics and long decay."""
    duration = 1.6
    n = int(SAMPLE_RATE * duration)
    samples = []
    f0 = 880.0  # A5
    for i in range(n):
        t = i / SAMPLE_RATE
        env = math.exp(-3.5 * t)
        # Bell acoustics: partials at 1.0, 2.0, 3.0, 4.2 with differing decay rates
        s = (
            math.sin(2 * math.pi * f0 * t) * 0.6
            + math.sin(2 * math.pi * f0 * 2.0 * t) * 0.3 * math.exp(-2.0 * t)
            + math.sin(2 * math.pi * f0 * 3.0 * t) * 0.15 * math.exp(-4.0 * t)
            + math.sin(2 * math.pi * f0 * 4.2 * t) * 0.1 * math.exp(-6.0 * t)
        ) * env
        samples.append(s * 0.9)
    write_wav("bell.wav", samples)


def gen_coin():
    """Bright two-tone pickup chime (B5 -> E6)."""
    duration = 0.35
    n = int(SAMPLE_RATE * duration)
    samples = []
    t_split = 0.08
    for i in range(n):
        t = i / SAMPLE_RATE
        if t < t_split:
            freq = 987.77  # B5
            env = min(1.0, t / 0.005)
        else:
            freq = 1318.51  # E6
            t_sub = t - t_split
            env = math.exp(-9.0 * t_sub)
        # Add a light sparkle harmonic
        s = (math.sin(2 * math.pi * freq * t) + 0.25 * math.sin(4 * math.pi * freq * t)) * env
        samples.append(s * 0.8)
    write_wav("coin.wav", samples)


def gen_click():
    """Short crisp mechanical button click."""
    duration = 0.05
    n = int(SAMPLE_RATE * duration)
    samples = []
    for i in range(n):
        t = i / SAMPLE_RATE
        env = math.exp(-80.0 * t)
        freq = 1200.0 - 800.0 * (t / duration)
        s = math.sin(2 * math.pi * freq * t) * env
        samples.append(s * 0.7)
    write_wav("click.wav", samples)


def gen_chime():
    """Pleasant 3-note ascending arpeggio (C6, E6, G6)."""
    duration = 0.8
    n = int(SAMPLE_RATE * duration)
    notes = [1046.5, 1318.5, 1567.98]  # C6, E6, G6
    step = 0.12
    samples = []
    for i in range(n):
        t = i / SAMPLE_RATE
        s_total = 0.0
        for idx, freq in enumerate(notes):
            t_start = idx * step
            if t >= t_start:
                t_note = t - t_start
                env = math.exp(-6.0 * t_note)
                s_total += math.sin(2 * math.pi * freq * t_note) * env * 0.35
        samples.append(s_total)
    write_wav("chime.wav", samples)


def gen_fanfare():
    """Triumphant short fanfare jingle (C5, G5, C6)."""
    duration = 1.0
    n = int(SAMPLE_RATE * duration)
    notes = [(0.0, 0.15, 523.25), (0.15, 0.30, 783.99), (0.30, 0.95, 1046.5)]
    samples = []
    for i in range(n):
        t = i / SAMPLE_RATE
        s_total = 0.0
        for t_start, t_end, freq in notes:
            if t >= t_start:
                t_rel = t - t_start
                env = math.exp(-4.0 * t_rel) if t >= t_end - 0.05 else min(1.0, t_rel / 0.01)
                s_total += (math.sin(2 * math.pi * freq * t_rel) + 0.2 * math.sin(4 * math.pi * freq * t_rel)) * env * 0.4
        samples.append(s_total)
    write_wav("fanfare.wav", samples)


def gen_door_open():
    """Low wooden mechanical slide/creak."""
    duration = 0.6
    n = int(SAMPLE_RATE * duration)
    samples = []
    for i in range(n):
        t = i / SAMPLE_RATE
        env = math.sin(math.pi * (t / duration)) ** 0.5
        freq = 160.0 + 80.0 * math.sin(30.0 * t)
        s = math.sin(2 * math.pi * freq * t) * env * 0.6
        samples.append(s)
    write_wav("door_open.wav", samples)


if __name__ == "__main__":
    gen_bell()
    gen_coin()
    gen_click()
    gen_chime()
    gen_fanfare()
    gen_door_open()