Allow passing a filename to dwvsh

The dwvsh binary may optionally take a filename as the last argument.
Instead of spawning an interactive shell, it will instead run a shell
program at the path specified.

1 files changed, 29 insertions, 2 deletions

diff --git a/src/main.rs b/src/main.rs
index f87b69d..98b49ed 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -82,7 +82,7 @@ fn repl(away: &mut Arc<Mutex<bool>>, env: &mut Environment) {
     }
 }
 
-fn options() {
+fn options(env: &mut Environment) {
     let args: Vec<String> = env::args().collect();
     for arg in args.iter() {
         if arg.eq("--version") {
@@ -94,6 +94,33 @@ fn options() {
             std::process::exit(0);
         }
     }
+
+    match args.last() {
+        Some(arg) => {
+            if args.len() > 1 && !arg.starts_with('-') {
+                let poetry = std::fs::read_to_string(arg)
+                    .expect(format!("dwvsh: can't open input file: {}", arg).as_str());
+                let poem = Poem::read(poetry, env);
+                let poem = match poem {
+                    Ok(poem) => poem,
+                    Err(e) => {
+                        eprintln!("dwvsh: {}", e.to_string().to_lowercase());
+                        std::process::exit(1);
+                    }
+                };
+
+                // Recite the poem
+                match poem.recite(env) {
+                    Ok(_) => {}
+                    Err(e) => eprintln!("dwvsh: {}", e.to_string().to_lowercase()),
+                }
+
+                // Quit
+                std::process::exit(0);
+            }
+        }
+        None => {}
+    }
 }
 
 /// Shell entry
@@ -123,7 +150,7 @@ fn main() {
     };
 
     // Parse flags and other arguments
-    options();
+    options(&mut env);
 
     // Begin evaluating commands
     repl(&mut away, &mut env);