feat(cli): Split CLI into function for subcommands and validate args

src/main.rs

@@ -1,9 +1,15 @@
 use structopt::StructOpt;
+use structopt::clap::AppSettings;
+use std::path;
+use std::vec;
+use std::fs;
+use std::io;
 
 /// The command line interface to the CaSILE toolkit, a book publishing
 /// workflow employing SILE and other wizardry
 #[derive(StructOpt)]
 #[structopt(version = env!("VERGEN_SEMVER"))]
+#[structopt(setting = AppSettings::InferSubcommands)]
 struct Cli {
 
     /// Activate debug mode
@@ -15,7 +21,7 @@ struct Cli {
     verbose: bool,
 
     #[structopt(subcommand)]
-    command: Subcommand,
+    subcommand: Subcommand,
 
 }
 
@@ -24,15 +30,19 @@ enum Subcommand {
 
     /// Executes a make target
     Make {
+
         /// Target as defined in CaSILE makefile
-        target: String
+        target: Vec<String>,
+
     },
 
     /// Configure a book repository
     Setup {
-        #[structopt(default_value = "./")]
+
         /// Path to project repository
-        path: String
+        #[structopt(parse(from_os_str), default_value = "./")]
+        path: path::PathBuf,
+
     },
 
     /// Pass through other commands to shell
@@ -41,9 +51,55 @@ enum Subcommand {
 
 }
 
-fn main() {
+fn main () -> io::Result<()> {
 
     let args = Cli::from_args();
-    println!("Insert magic potion! (Unimplemented)");
 
+    if args.debug {
+        println!("User requested debug mode")
+    }
+
+    if args.verbose {
+        println!("User requested verbose output")
+    }
+
+    return match args.subcommand {
+        Subcommand::Make{ target } => make(target),
+        Subcommand::Setup{ path } => setup(path),
+        _a => shell(),
+    }
+
+}
+
+fn make (_target: vec::Vec<String>) -> io::Result<()> {
+
+    println!("Make make make sense or I’ll make you make makefiles.");
+
+    Ok(())
+}
+
+fn setup (path: path::PathBuf) -> io::Result<()> {
+
+    let pathmeta = fs::metadata(path);
+
+    match pathmeta {
+        Ok(file) => {
+            if file.is_dir() {
+                println!("Run setup, “They said you were this great colossus!”")
+            } else {
+                println!("Not a dir, Frank!")
+            }
+        }
+        Err(error) => { return Err(error.into()) },
+    };
+
+    Ok(())
+
+}
+
+fn shell () -> io::Result<()> {
+
+    println!("Ship all this off to the shell, maybe they can handle it.");
+
+    Ok(())
 }