feat: basic functionality

src/cli.rs

@@ -0,0 +1,43 @@
+use clap::Parser;
+use std::path::PathBuf;
+
+/// Enter chroot environments with Linux namespaces
+#[derive(Parser, Debug, Clone)]
+#[command(author, version, about, long_about = None, override_usage = "ecr [OPTIONS] <DISTRO[:VERSION]> -- [COMMAND]...")]
+pub struct Args {
+    /// Distribution name (e.g., ubuntu, debian, arch, alpine, fedora)
+    #[arg(value_name = "DISTRO[:VERSION]")]
+    pub distro: String,
+
+    /// Target architecture
+    #[arg(short, long, value_name = "ARCH")]
+    pub arch: Option<String>,
+
+    /// Directory to overlay-mount (can be specified multiple times, default: current directory)
+    #[arg(long, value_name = "PATH")]
+    pub bind: Vec<PathBuf>,
+
+    /// Directory to bind-mount read-write at /mnt/<basename> (overrides regular bind, can be specified multiple times)
+    #[arg(long, value_name = "PATH")]
+    pub bind_rw: Vec<PathBuf>,
+
+    /// Download fresh tarball, ignore cache
+    #[arg(long)]
+    pub no_cache: bool,
+
+    /// Skip mounting any directory
+    #[arg(long)]
+    pub no_bind: bool,
+
+    /// Print diagnostic messages (URLs, manifest info, extraction steps, etc.)
+    #[arg(short = 'v', long)]
+    pub verbose: bool,
+
+    /// Command to run inside the chroot (default: interactive shell)
+    #[arg(
+        trailing_var_arg = true,
+        allow_hyphen_values = true,
+        value_name = "COMMAND"
+    )]
+    pub command: Vec<String>,
+}