using UnityEngine;

/// <summary>
/// Процедурный синтезатор звуковых эффектов для интерфейса терминала, кнопок и записок.
/// Создает чистые звуки прямо в оперативной памяти (AudioClip.Create) без внешних файлов.
/// </summary>
public static class GameAudioSynthesizer
{
    private static AudioSource globalAudioSource;

    private static AudioSource GetAudioSource()
    {
        if (globalAudioSource == null)
        {
            var go = new GameObject("ProceduralUIAudioSource");
            if (Application.isPlaying)
            {
                Object.DontDestroyOnLoad(go);
            }
            globalAudioSource = go.AddComponent<AudioSource>();
            globalAudioSource.playOnAwake = false;
            globalAudioSource.spatialBlend = 0f; // 2D звук интерфейса
            globalAudioSource.ignoreListenerPause = true; // Работает даже при Time.timeScale = 0
        }
        return globalAudioSource;
    }

    /// <summary>
    /// Короткий высокий бип нажатия кнопки терминала (1200 Hz)
    /// </summary>
    public static void PlayKeypadBeep()
    {
        AudioClip clip = CreateToneClip(1200f, 0.05f, 0.25f);
        PlayOneShot(clip, 0.35f);
    }

    /// <summary>
    /// Звук сброса/стирания цифры (700 Hz)
    /// </summary>
    public static void PlayKeypadClear()
    {
        AudioClip clip = CreateToneClip(700f, 0.08f, 0.3f);
        PlayOneShot(clip, 0.3f);
    }

    /// <summary>
    /// Звук ошибки ввода (низкий двойной зуммер 160Hz)
    /// </summary>
    public static void PlayErrorCode()
    {
        int sampleRate = 44100;
        int samples = (int)(sampleRate * 0.25f);
        float[] data = new float[samples];
        for (int i = 0; i < samples; i++)
        {
            float t = (float)i / sampleRate;
            float freq = 160f;
            float pulse = Mathf.Sin(2f * Mathf.PI * 18f * t) > 0f ? 1f : 0f;
            data[i] = Mathf.Sin(2f * Mathf.PI * freq * t) * pulse * (1f - (float)i / samples) * 0.4f;
        }

        AudioClip clip = AudioClip.Create("ErrorCodeTone", samples, 1, sampleRate, false);
        clip.SetData(data, 0);
        PlayOneShot(clip, 0.45f);
    }

    /// <summary>
    /// Торжественный трезвук успеха (C-E-G мажорный перелив)
    /// </summary>
    public static void PlaySuccessChime()
    {
        int sampleRate = 44100;
        int samples = (int)(sampleRate * 0.6f);
        float[] data = new float[samples];

        float[] freqs = new float[] { 523.25f, 659.25f, 783.99f, 1046.50f };
        for (int i = 0; i < samples; i++)
        {
            float t = (float)i / sampleRate;
            float sampleVal = 0f;

            for (int f = 0; f < freqs.Length; f++)
            {
                float startTime = f * 0.1f;
                if (t >= startTime)
                {
                    float noteTime = t - startTime;
                    float env = Mathf.Exp(-noteTime * 4.5f);
                    sampleVal += Mathf.Sin(2f * Mathf.PI * freqs[f] * noteTime) * env * 0.2f;
                }
            }
            data[i] = Mathf.Clamp(sampleVal, -0.9f, 0.9f);
        }

        AudioClip clip = AudioClip.Create("SuccessChime", samples, 1, sampleRate, false);
        clip.SetData(data, 0);
        PlayOneShot(clip, 0.5f);
    }

    /// <summary>
    /// Звук разворачивания/чтения секретной записки (шум бумаги + легкий звон)
    /// </summary>
    public static void PlayPaperRustle()
    {
        int sampleRate = 44100;
        int samples = (int)(sampleRate * 0.18f);
        float[] data = new float[samples];

        System.Random rnd = new System.Random(42);
        for (int i = 0; i < samples; i++)
        {
            float env = 1f - (float)i / samples;
            float noise = ((float)rnd.NextDouble() * 2f - 1f) * 0.15f;
            float chime = Mathf.Sin(2f * Mathf.PI * 1400f * ((float)i / sampleRate)) * 0.12f;
            data[i] = (noise + chime) * env;
        }

        AudioClip clip = AudioClip.Create("PaperRustle", samples, 1, sampleRate, false);
        clip.SetData(data, 0);
        PlayOneShot(clip, 0.4f);
    }

    private static AudioClip CreateToneClip(float frequency, float duration, float volume)
    {
        int sampleRate = 44100;
        int samples = (int)(sampleRate * duration);
        float[] data = new float[samples];

        for (int i = 0; i < samples; i++)
        {
            float t = (float)i / sampleRate;
            float env = 1f - ((float)i / samples);
            data[i] = Mathf.Sin(2f * Mathf.PI * frequency * t) * env * volume;
        }

        AudioClip clip = AudioClip.Create($"Tone_{frequency}", samples, 1, sampleRate, false);
        clip.SetData(data, 0);
        return clip;
    }

    private static void PlayOneShot(AudioClip clip, float volumeScale)
    {
        if (clip == null) return;
        var src = GetAudioSource();
        if (src != null)
        {
            src.PlayOneShot(clip, volumeScale);
        }
    }
}