Add an order argument

2 files changed, 25 insertions, 12 deletions

diff --git a/src/lib.rs b/src/lib.rs
index 74e37b2..bb9ebee 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -13,14 +13,18 @@ pub fn parse_feed(xml: &str) -> Result<Channel, rss::Error> {
 }
 
 /// Extract the audio URLs from the given channel
-pub fn get_audio_urls(channel: &Channel) -> Vec<(usize, &str)> {
-    channel
-        .items()
-        .iter()
-        .rev()
-        .enumerate()
-        .filter_map(|(i, item)| item.enclosure().map(|e| (i + 1, e.url())))
-        .collect()
+pub fn get_audio_urls(channel: &Channel, newest_first: bool) -> Vec<(usize, &str)> {
+    let iter = channel.items().iter();
+    if newest_first {
+        iter.enumerate()
+            .filter_map(|(i, item)| item.enclosure().map(|e| (i + 1, e.url())))
+            .collect()
+    } else {
+        iter.rev()
+            .enumerate()
+            .filter_map(|(i, item)| item.enclosure().map(|e| (i + 1, e.url())))
+            .collect()
+    }
 }
 
 /// Download the given audio file to the supplied directory
diff --git a/src/main.rs b/src/main.rs
index 50c59e3..ab8e299 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,6 +1,12 @@
-use clap::Parser;
+use clap::{Parser, ValueEnum};
 use simple_rss_podcast_downloader::*;
 
+#[derive(ValueEnum, Clone, Debug)]
+enum Order {
+    Newest,
+    Oldest,
+}
+
 #[derive(Parser, Debug)]
 #[command(author, version, about)]
 struct Cli {
@@ -8,18 +14,21 @@ struct Cli {
     #[arg(default_value = ".")]
     output_dir: String,
     #[arg(short, long)]
-    numbered: bool,
+    numbered: bool, // Whether to prefix the episode number
+    #[arg(long, value_enum, default_value_t = Order::Oldest)]
+    order: Order, // Order of download and numbering
 }
 
 fn main() -> Result<(), Box<dyn std::error::Error>> {
     let args = Cli::parse();
 
-    println!("Feed RSS feed from: {}", args.feed_url);
+    println!("Fetching RSS feed from: {}", args.feed_url);
 
     let xml = fetch_feed(&args.feed_url)?;
     let channel = parse_feed(&xml)?;
     let pad = channel.items().len().to_string().len();
-    for (i, url) in get_audio_urls(&channel) {
+    let newest_first = matches!(args.order, Order::Newest);
+    for (i, url) in get_audio_urls(&channel, newest_first) {
         let prefix = if args.numbered {
             Some(format!("{:0width$}", i, width = pad))
         } else {