Rust - Calculate Total Length of MP4s in Folder

rust_mp4_length_sum.rs

use std::process::Command;
use walkdir::WalkDir;
use regex::Regex;

/*
[package]
name = "rust_playground"
version = "0.1.0"
edition = "2021"

[dependencies]
walkdir = "2.5"
regex = "1.11"
 */

/// Finds all MP4 files recursively in the given directory.
fn find_mp4_files(directory: &str) -> Vec<String> {
    let mut mp4_files = Vec::new();

    for entry in WalkDir::new(directory).into_iter().filter_map(Result::ok) {
        if let Some(ext) = entry.path().extension() {
            if ext == "mp4" {
                if let Some(path) = entry.path().to_str() {
                    mp4_files.push(path.to_string());
                }
            }
        }
    }

    mp4_files
}

/// Uses ffprobe to get the duration of an MP4 file.
fn get_mp4_duration(file_path: &str) -> Option<f64> {
    let output = Command::new("ffprobe")
        .args([
            "-v", "error",
            "-show_entries", "format=duration",
            "-of", "json",
            file_path,
        ])
        .output()
        .ok()?;

    let output_str = String::from_utf8_lossy(&output.stdout);

    // Regex to extract the duration from JSON output
    let re = Regex::new(r#""duration"\s*:\s*"([\d.]+)""#).unwrap();
    if let Some(caps) = re.captures(&output_str) {
        if let Some(duration_str) = caps.get(1) {
            return duration_str.as_str().parse::<f64>().ok();
        }
    }

    None
}

/// Converts total seconds into HH:MM:SS format.
fn format_time(seconds: f64) -> String {
    let hours = (seconds / 3600.0) as u32;
    let minutes = ((seconds % 3600.0) / 60.0) as u32;
    let seconds = (seconds % 60.0) as u32;
    format!("{:02}:{:02}:{:02}", hours, minutes, seconds)
}

fn main() {
    let base_directory = "."; // Change this path
    let mp4_files = find_mp4_files(base_directory);

    if mp4_files.is_empty() {
        println!("No MP4 files found.");
        return;
    }

    let mut total_duration = 0.0;

    for file in &mp4_files {
        if let Some(duration) = get_mp4_duration(file) {
            total_duration += duration;
        } else {
            println!("Failed to get duration for: {}", file);
        }
    }

    println!(
        "Total MP4 duration: {} ({:.2} seconds)",
        format_time(total_duration),
        total_duration
    );
}