ffms2 0.2.0

FFI bindings to ffms2
use crate::index::*;
use crate::resample::*;
use crate::*;

use ffms2_sys::*;

use std::ffi::c_void;
use std::ffi::CString;
use std::mem;
use std::path::Path;

simple_enum!(
    AudioChannel,
    (
        CH_FRONT_LEFT,
        CH_FRONT_RIGHT,
        CH_FRONT_CENTER,
        CH_LOW_FREQUENCY,
        CH_BACK_LEFT,
        CH_BACK_RIGHT,
        CH_FRONT_LEFT_OF_CENTER,
        CH_FRONT_RIGHT_OF_CENTER,
        CH_BACK_CENTER,
        CH_SIDE_LEFT,
        CH_SIDE_RIGHT,
        CH_TOP_CENTER,
        CH_TOP_FRONT_LEFT,
        CH_TOP_FRONT_CENTER,
        CH_TOP_FRONT_RIGHT,
        CH_TOP_BACK_LEFT,
        CH_TOP_BACK_CENTER,
        CH_TOP_BACK_RIGHT,
        CH_STEREO_LEFT,
        CH_STEREO_RIGHT,
    )
);

simple_enum!(
    AudioDelay,
    (DELAY_NO_SHIFT, DELAY_TIME_ZERO, DELAY_FIRST_VIDEO_TRACK)
);

simple_enum!(
    MatrixEncoding,
    (
        MATRIX_ENCODING_NONE,
        MATRIX_ENCODING_DOBLY,
        MATRIX_ENCODING_PRO_LOGIC_II,
        MATRIX_ENCODING_PRO_LOGIC_IIX,
        MATRIX_ENCODING_PRO_LOGIC_IIZ,
        MATRIX_ENCODING_DOLBY_EX,
        MATRIX_ENCODING_DOLBY_HEADPHONE,
    )
);

create_struct!(
    AudioProperties,
    audio_properties,
    FFMS_AudioProperties,
    (
        SampleFormat,
        SampleRate,
        BitsPerSample,
        Channels,
        ChannelLayout,
        NumSamples,
        FirstTime,
        LastTime,
        LastEndTime,
    ),
    (0, 0, 0, 0, 0, 0, 0.0, 0.0, 0.0)
);

pub struct AudioSource {
    audio_source: *mut FFMS_AudioSource,
}

unsafe impl Send for AudioSource {}

impl AudioSource {
    pub fn new(
        SourceFile: &Path,
        Track: usize,
        Index: &Index,
        DelayMode: isize,
    ) -> Result<Self, Error> {
        let source = CString::new(SourceFile.to_str().unwrap()).unwrap();
        let mut error: Error = Default::default();
        let audio_source = unsafe {
            FFMS_CreateAudioSource(
                source.as_ptr(),
                Track as i32,
                Index.as_mut_ptr(),
                DelayMode as i32,
                error.as_mut_ptr(),
            )
        };

        if audio_source.is_null() {
            Err(error)
        } else {
            Ok(AudioSource { audio_source })
        }
    }

    pub fn GetAudioProperties(&self) -> AudioProperties {
        let audio_prop = unsafe { FFMS_GetAudioProperties(self.audio_source) };
        let ref_audio = unsafe { &*audio_prop };

        AudioProperties {
            audio_properties: *ref_audio,
        }
    }

    pub fn GetAudio<T>(
        &self,
        Start: usize,
        Count: usize,
    ) -> Result<Vec<T>, Error> {
        let mut error: Error = Default::default();
        let audio_prop = self.GetAudioProperties();
        let num_samples = audio_prop.NumSamples;

        if Start as i64 > (num_samples - 1) || Count as i64 > (num_samples - 1)
        {
            panic!("Requesting samples beyond the stream end");
        }

        let num_channels = audio_prop.Channels;
        let num_elements = Count * num_channels as usize;

        let Buf: Vec<T> = Vec::with_capacity(num_elements);
        let mut Buf = mem::ManuallyDrop::new(Buf);
        let buf_ptr = Buf.as_mut_ptr();

        let err = unsafe {
            FFMS_GetAudio(
                self.audio_source,
                buf_ptr as *mut c_void,
                Start as i64,
                Count as i64,
                error.as_mut_ptr(),
            )
        };

        if err != 0 {
            Err(error)
        } else {
            let audio_vec = unsafe {
                Vec::from_raw_parts(buf_ptr, num_elements, num_elements)
            };

            Ok(audio_vec)
        }
    }

    pub fn CreateResampleOptions(&self) -> ResampleOptions {
        let res_opt = unsafe { FFMS_CreateResampleOptions(self.audio_source) };
        let ref_res = unsafe { &*res_opt };

        ResampleOptions::create_struct(ref_res)
    }

    pub fn SetOutputFormatA(
        &self,
        options: &ResampleOptions,
    ) -> Result<(), Error> {
        let mut error: Error = Default::default();
        let err = unsafe {
            FFMS_SetOutputFormatA(
                self.audio_source,
                options.as_ptr(),
                error.as_mut_ptr(),
            )
        };

        if err != 0 {
            Err(error)
        } else {
            Ok(())
        }
    }

    pub(crate) fn as_mut_ptr(&mut self) -> *mut FFMS_AudioSource {
        self.audio_source
    }
}

impl Drop for AudioSource {
    fn drop(&mut self) {
        unsafe {
            FFMS_DestroyAudioSource(self.audio_source);
        }
    }
}