feat(version): Include `yt-dlp` and `python` version in `--version`

Both are run-time dependencies and need to be up-to-date (especially,
`yt-dlp`)

3 files changed, 43 insertions, 1 deletions

diff --git a/yt/src/cli.rs b/yt/src/cli.rs
index d7e084a..5e7af5b 100644
--- a/yt/src/cli.rs
+++ b/yt/src/cli.rs
@@ -22,7 +22,7 @@ use crate::{
 };
 
 #[derive(Parser, Debug)]
-#[clap(author, version, about, long_about = None)]
+#[clap(author, about, long_about = None)]
 #[allow(clippy::module_name_repetitions)]
 /// An command line interface to select, download and watch videos
 pub struct CliArgs {
@@ -30,6 +30,10 @@ pub struct CliArgs {
     /// The subcommand to execute [default: select]
     pub command: Option<Command>,
 
+    /// Show the version and exit
+    #[arg(long, short = 'V', action= ArgAction::SetTrue)]
+    pub version: bool,
+
     /// Increase message verbosity
     #[arg(long="verbose", short = 'v', action = ArgAction::Count)]
     pub verbosity: u8,
diff --git a/yt/src/main.rs b/yt/src/main.rs
index fbfdac0..3097eea 100644
--- a/yt/src/main.rs
+++ b/yt/src/main.rs
@@ -50,6 +50,7 @@ pub mod status;
 pub mod storage;
 pub mod subscribe;
 pub mod update;
+pub mod version;
 pub mod videos;
 pub mod watch;
 
@@ -59,6 +60,11 @@ pub mod watch;
 async fn main() -> Result<()> {
     let args = cli::CliArgs::parse();
 
+    if args.version {
+        version::show()?;
+        return Ok(());
+    }
+
     // The default verbosity is 1 (Warn)
     let verbosity: u8 = args.verbosity + 1;
 
diff --git a/yt/src/version/mod.rs b/yt/src/version/mod.rs
new file mode 100644
index 0000000..369541e
--- /dev/null
+++ b/yt/src/version/mod.rs
@@ -0,0 +1,32 @@
+use std::process::Command;
+
+use anyhow::{Context, Result};
+
+fn get_cmd_version(cmd: &str) -> Result<String> {
+    let out = String::from_utf8(
+        Command::new(cmd)
+            .arg("--version")
+            .output()
+            .with_context(|| format!("Failed to run `{cmd} --version`"))?
+            .stdout,
+    )
+    .context("Failed to interpret output as utf8")?;
+
+    Ok(out.trim().to_owned())
+}
+
+pub fn show() -> Result<()> {
+    let python_version = get_cmd_version("python")?;
+    let yt_dlp_version = get_cmd_version("yt-dlp")?;
+
+    println!(
+        "{}: {}
+
+python: {python_version}
+yt-dlp: {yt_dlp_version}",
+        env!("CARGO_PKG_NAME"),
+        env!("CARGO_PKG_VERSION"),
+    );
+
+    Ok(())
+}