feat(check): check for old packages

This only considers packages which were explicitly installed, and which
aren't depended on by anything. So these could be considered the most
"top level" packages. It's common to install things and then forget
about them, incurring a perpetual upgrade cost when doing -Syu.

rust/aura-pm/i18n/en-US/aura_pm.ftl

@@ -170,6 +170,9 @@ check-cache-missing = Every installed official package has a tarball?
 check-cache-missing-fix = Fix: You can download missing official tarballs with { $command }
 check-cache-missing-for = Every installed AUR package has a tarball?
 check-cache-missing-for-fix = Fix: View the missing packages with { $cmd } and reinstall them manually.
+check-pkgs = Package Status
+check-pkgs-old = All explicitly installed, non-dep packages are up to date?
+check-pkgs-old-warn = { $pkg } was last updated { $days } ago.
 
 # Configuration (conf)
 conf-toml-err = Failed to serialize current config.

rust/aura-pm/src/command/check.rs

@@ -5,6 +5,7 @@ use crate::error::Nested;
 use crate::localization::Localised;
 use crate::utils::PathStr;
 use crate::{aura, executable, green};
+use alpm::PackageReason;
 use colored::*;
 use from_variants::FromVariants;
 use i18n_embed::fluent::FluentLanguageLoader;
@@ -16,6 +17,7 @@ use std::collections::HashSet;
 use std::ops::Not;
 use std::path::{Path, PathBuf};
 use std::process::Command;
+use std::time::{SystemTime, UNIX_EPOCH};
 
 pub(crate) const GOOD: &str = "✓";
 pub(crate) const WARN: &str = "!";
@@ -58,6 +60,7 @@ pub(crate) fn check(fll: &FluentLanguageLoader, env: &Env) -> Result<(), Error>
     makepkg_config(fll);
     snapshots(fll, &env.backups.snapshots, &caches);
     cache(fll, &alpm, pool, &caches);
+    packages(fll, &alpm);
     green!(fll, "common-done");
 
     Ok(())
@@ -450,3 +453,56 @@ fn pacnew_work() -> Option<Vec<(PathBuf, u64)>> {
 
     Some(bads)
 }
+
+fn packages(fll: &FluentLanguageLoader, alpm: &Alpm) {
+    aura!(fll, "check-pkgs");
+    old_packages(fll, alpm);
+}
+
+fn old_packages(fll: &FluentLanguageLoader, alpm: &Alpm) {
+    let now = SystemTime::now();
+
+    if let Ok(dur) = now.duration_since(UNIX_EPOCH) {
+        let sec = dur.as_secs();
+
+        let old: Vec<_> = alpm
+            .as_ref()
+            .localdb()
+            .pkgs()
+            .into_iter()
+            // Only consider packages that you explicitly installed...
+            .filter(|p| p.reason() == PackageReason::Explicit)
+            // ...and aren't required by anything.
+            .filter(|p| p.required_by().is_empty())
+            .filter_map(|p| {
+                p.install_date().and_then(|id| {
+                    let diff = (sec - id as u64) / SECS_IN_DAY;
+                    if diff > 365 {
+                        Some((p, diff))
+                    } else {
+                        None
+                    }
+                })
+            })
+            .collect();
+
+        let good = old.is_empty();
+        let symb = if good { GOOD.green() } else { WARN.yellow() };
+        println!("  [{}] {}", symb, fl!(fll, "check-pkgs-old"));
+
+        let len = old.len();
+        for (i, (p, diff)) in old.into_iter().enumerate() {
+            let pkg = p.name().cyan().to_string();
+
+            let day = if diff < 365 * 2 {
+                diff.to_string().yellow().to_string()
+            } else {
+                diff.to_string().red().to_string()
+            };
+
+            let msg = fl!(fll, "check-pkgs-old-warn", pkg = pkg, days = day);
+            let arrow = if i + 1 == len { "└─" } else { "├─" };
+            println!("      {} {}", arrow, msg);
+        }
+    }
+}