rust_combiner/src/lib.rs

use pyo3::prelude::*; 
use pyo3::wrap_pyfunction; 
use std::fs::File; 
use std::io::Write;
use std::process::Command;
use uuid::Uuid;

#[pyfunction] 
fn combine_clips(clips: Vec<String>) -> PyResult<String> { 
let paths: Vec<&str> = clips.iter().map(|s| s.as_str()).collect(); 
concat_videos(paths) 

}

fn concat_videos(clips: Vec<&str>) -> PyResult<String> { 
// Step 1: Write file list
let list_file = format!("/tmp/clips_{}.txt", Uuid::new_v4());
let mut file = File::create(&list_file) 
.map_err(|e| pyo3::exceptions::PyIOError::new_err(e.to_string()))?;
for clip in &clips { writeln!(file, "file '{}'", clip)
.map_err(|e| pyo3::exceptions::PyIOError::new_err(e.to_string()))?; 
}

// Step 2: Run FFmpeg
let output_file = format!("/tmp/final_video_{}.mp4", Uuid::new_v4());
let status = Command::new("ffmpeg")
    .args(&[
        "-y",
        "-f", "concat",
        "-safe", "0",
        "-i", &list_file,
        "-c", "copy",
        &output_file,
    ])
    .status()
    .map_err(|e| pyo3::exceptions::PyRuntimeError::new_err(e.to_string()))?;

if status.success() {
    Ok(output_file)
} else {
    Err(pyo3::exceptions::PyRuntimeError::new_err("FFmpeg command failed"))
}

}

#[pymodule] 
fn rust_combiner(_py: Python, m: &PyModule) -> PyResult<()> {
m.add_function(wrap_pyfunction!(combine_clips, m)?)?;
Ok(()) 
}