#include "../codec/codec.h"

static inline f32 apply_volume_f32(f32 *data, size_t sample_count, s32 channel_count, f32 volume, f32 limit, f32 step)
{
    for (u32 i = 0; i < sample_count; i++) {
        if (step != 0.f && i % channel_count == 0) {
            volume = CLAMP(volume + step, 0.f, limit);
        }
        f64 sample = (f64)data[i];
        sample *= volume;
        data[i] = (f32)CLAMP(sample, -1.0, 1.0);
    }
    return volume;
}

static inline f32 apply_volume_s32(s32 *data, size_t sample_count, s32 channel_count, f32 volume, f32 limit, f32 step)
{
    for (u32 i = 0; i < sample_count; i++) {
        if (step != 0.f && i % channel_count == 0) {
            volume = CLAMP(volume + step, 0.f, limit);
        }
        f64 sample = (f64)data[i];
        sample *= volume;
        data[i] = (s32)CLAMP(sample, (f64)INT32_MIN, (f64)INT32_MAX);
    }
    return volume;
}

static inline f32 apply_volume_s16(s16 *data, size_t sample_count, s32 channel_count, f32 volume, f32 limit, f32 step)
{
    for (u32 i = 0; i < sample_count; i++) {
        if (step != 0.f && i % channel_count == 0) {
            volume = CLAMP(volume + step, 0.f, limit);
        }
        f64 sample = (f64)data[i];
        sample *= volume;
        data[i] = (s16)CLAMP(sample, (f64)INT16_MIN, (f64)INT16_MAX);
    }
    return volume;
}

static inline f32 apply_volume(u8 *data, size_t size, struct camu_audio_format *fmt, f32 volume, f32 user, f32 step)
{
    size_t sample_count;
    f32 limit = MAX(user, volume);
    switch (camu_audio_format_bytes_per_sample(fmt)) {
    case 4:
        sample_count = size / 4;
        if (fmt->format == CAMU_SAMPLE_FORMAT_S32) {
            return apply_volume_s32((s32 *)data, sample_count, fmt->channel_count, volume, limit, step);
        } else if (fmt->format == CAMU_SAMPLE_FORMAT_FLT) {
            return apply_volume_f32((f32 *)data, sample_count, fmt->channel_count, volume, limit, step);
        }
        break;
    case 2:
        sample_count = size / 2;
        if (fmt->format == CAMU_SAMPLE_FORMAT_S16) {
            return apply_volume_s16((s16 *)data, sample_count, fmt->channel_count, volume, limit, step);
        }
        break;
    }
    return volume;
}