feat(pkg-mgr): implement pkg-show command

Add `pkg-show` to display installed packages and their versions,
removing its NOT_IMPL marker from help. Include internal commands
to load enabled package paths and completion scripts.

1 files changed, 104 insertions, 0 deletions

diff --git a/mingling_cli/src/pkg_mgr/cmd_internal_loadpkgs.rs b/mingling_cli/src/pkg_mgr/cmd_internal_loadpkgs.rs
new file mode 100644
index 0000000..b4928ce
--- /dev/null
+++ b/mingling_cli/src/pkg_mgr/cmd_internal_loadpkgs.rs
@@ -0,0 +1,104 @@
+use std::{
+    fs, io,
+    path::{Path, PathBuf},
+};
+
+use mingling::{
+    Routable,
+    macros::{buffer, command, pack, r_println, renderer, routeify},
+};
+
+use crate::{
+    Next,
+    pkg_mgr::{ErrorNoDataDirectory, ResPackagesDir},
+};
+
+// Version directory paths of every enabled package.
+pack!(ResultLoadPkgsPaths = Vec<PathBuf>);
+
+// Completion script paths of every enabled package.
+pack!(ResultLoadPkgsComps = Vec<PathBuf>);
+
+#[command(node = "__loadpkgs_path", routeify)]
+pub fn load_packages_paths(packages_dir: &ResPackagesDir) -> Next {
+    let packages_dir = &packages_dir.path;
+    if packages_dir.as_os_str().is_empty() {
+        return ErrorNoDataDirectory::default().to_chain();
+    }
+    let paths = enabled_version_dirs(packages_dir).map_err(|e| {
+        io::Error::new(
+            e.kind(),
+            format!("failed to read {}: {e}", packages_dir.display()),
+        )
+    })?;
+    ResultLoadPkgsPaths::new(paths).to_chain()
+}
+
+#[command(node = "__loadpkgs_comp_scripts", routeify)]
+pub fn load_packages_comp_scripts(packages_dir: &ResPackagesDir) -> Next {
+    let packages_dir = &packages_dir.path;
+    if packages_dir.as_os_str().is_empty() {
+        return ErrorNoDataDirectory::default().to_chain();
+    }
+    let scripts = comp_scripts(packages_dir).map_err(|e| {
+        io::Error::new(
+            e.kind(),
+            format!("failed to read {}: {e}", packages_dir.display()),
+        )
+    })?;
+    ResultLoadPkgsComps::new(scripts).to_chain()
+}
+
+#[renderer(buffer)]
+pub fn render_result_load_pkgs_paths(r: ResultLoadPkgsPaths) {
+    for path in r.inner {
+        r_println!("{}", path.display());
+    }
+}
+
+#[renderer(buffer)]
+pub fn render_result_load_pkgs_comps(r: ResultLoadPkgsComps) {
+    for path in r.inner {
+        r_println!("{}", path.display());
+    }
+}
+
+/// Version directories of every enabled package.
+///
+/// An enable file is a `name` file (no `@`) whose content is the enabled version.
+fn enabled_version_dirs(packages_dir: &Path) -> Result<Vec<PathBuf>, io::Error> {
+    let mut dirs = Vec::new();
+    for entry in fs::read_dir(packages_dir)? {
+        let entry = entry?;
+        if !entry.file_type().is_ok_and(|t| t.is_file()) {
+            continue;
+        }
+        let name = entry.file_name().to_string_lossy().into_owned();
+        if name.contains('@') {
+            continue;
+        }
+        let version = fs::read_to_string(entry.path())?;
+        dirs.push(packages_dir.join(format!("{name}@{}", version.trim())));
+    }
+    dirs.sort();
+    Ok(dirs)
+}
+
+/// Completion scripts inside every enabled version directory.
+fn comp_scripts(packages_dir: &Path) -> Result<Vec<PathBuf>, io::Error> {
+    let mut scripts = Vec::new();
+    for dir in enabled_version_dirs(packages_dir)? {
+        if !dir.is_dir() {
+            continue;
+        }
+        for entry in fs::read_dir(&dir)? {
+            let entry = entry?;
+            let name = entry.file_name().to_string_lossy().into_owned();
+            if name.contains("_comp") {
+                scripts.push(entry.path());
+            }
+        }
+    }
+    scripts.sort();
+    Ok(scripts)
+}