rust-mv3u/src/main.rs

use std::fs::File;
use std::io::{BufRead, BufReader, Result};
use std::collections::HashMap;
use std::env;
use std::fs;
use std::process;

fn main() -> Result<()> {
    let args: Vec<String> = env::args().collect();

    if args.len() < 3 {
        println!("At least two arguments are required");
        process::exit(1);
    }

    let rename_file = &args[1];
    let playlist_file = &args[2];
    println!("{:?}", rename_file);

    let file = File::open(rename_file)?;
    let mut renames = HashMap::new();
    for line in BufReader::new(file).lines() {
        let line = line?;
        let split: Vec<&str> = line.split("\t\t").collect();
        renames.insert(split[0].to_string(), split[1].to_string());
    }
    
    let mut outputs = Vec::new();

    let pls_file = File::open(playlist_file)?;
    for entry in BufReader::new(pls_file).lines() {
        let entry = entry?;
        let new = renames.get(&entry).unwrap_or(&entry).to_string();
        /*
        if new != &entry {
            println!("renamed “{}” to “{}”", entry, new);
        } else {
            println!("“{}” remains unchanged", entry);
        }
        */
        outputs.push(new);
    }
    let data = outputs.join("\n");
    fs::write("playlist2.m3u", data).expect("unable to write");
    Ok(())
}