feat: improve tab completion (#43)

crates/shell/src/completion.rs

@@ -7,6 +7,7 @@ use rustyline::{Context, Helper};
 use std::borrow::Cow::{self, Owned};
 use std::env;
 use std::fs;
+use std::path::Path;
 
 pub struct ShellCompleter;
 
@@ -22,41 +23,73 @@ impl Completer for ShellCompleter {
         let mut matches = Vec::new();
         let (start, word) = extract_word(line, pos);
 
+        let is_start = start == 0;
         // Complete filenames
-        complete_filenames(word, &mut matches);
+        complete_filenames(is_start, word, &mut matches);
 
         // Complete shell commands
-        complete_shell_commands(word, &mut matches);
+        complete_shell_commands(is_start, word, &mut matches);
 
         // Complete executables in PATH
-        complete_executables_in_path(word, &mut matches);
+        complete_executables_in_path(is_start, word, &mut matches);
 
         Ok((start, matches))
     }
 }
 
 fn extract_word(line: &str, pos: usize) -> (usize, &str) {
+    if line.ends_with(" ") {
+        return (pos, "");
+    }
     let words: Vec<_> = line[..pos].split_whitespace().collect();
     let word_start = words.last().map_or(0, |w| line.rfind(w).unwrap());
     (word_start, &line[word_start..pos])
 }
 
-fn complete_filenames(word: &str, matches: &mut Vec<Pair>) {
-    if let Ok(entries) = fs::read_dir(".") {
+fn complete_filenames(_is_start: bool, word: &str, matches: &mut Vec<Pair>) {
+    // Split the word into directory path and partial filename
+    let (dir_path, partial_name) = match word.rfind('/') {
+        Some(last_slash) => (&word[..=last_slash], &word[last_slash + 1..]),
+        None => ("", word),
+    };
+
+    // Determine the full directory path to search
+    let search_dir = if dir_path.starts_with('/') {
+        dir_path.to_string()
+    } else {
+        format!("./{}", dir_path)
+    };
+
+    if let Ok(entries) = fs::read_dir(Path::new(&search_dir)) {
         for entry in entries.flatten() {
             if let Ok(name) = entry.file_name().into_string() {
-                if name.starts_with(word) {
-                    matches.push(Pair {
-                        display: name.clone(),
-                        replacement: name,
-                    });
+                if name.starts_with(partial_name) {
+                    let full_path = format!("{}{}", dir_path, name);
+                    match entry.file_type() {
+                        Ok(file_type) if file_type.is_dir() => {
+                            matches.push(Pair {
+                                display: full_path.clone() + "/",
+                                replacement: full_path + "/",
+                            });
+                        }
+                        Ok(_) => {
+                            matches.push(Pair {
+                                display: full_path.clone(),
+                                replacement: full_path,
+                            });
+                        }
+                        Err(_) => {}
+                    }
                 }
             }
         }
     }
 }
 
-fn complete_shell_commands(word: &str, matches: &mut Vec<Pair>) {
+fn complete_shell_commands(is_start: bool, word: &str, matches: &mut Vec<Pair>) {
+    if !is_start {
+        return;
+    }
     let shell_commands = ["ls", "cat", "cd", "pwd", "echo", "grep"];
     for &cmd in &shell_commands {
         if cmd.starts_with(word) {
@@ -68,7 +101,10 @@ fn complete_shell_commands(word: &str, matches: &mut Vec<Pair>) {
     }
 }
 
-fn complete_executables_in_path(word: &str, matches: &mut Vec<Pair>) {
+fn complete_executables_in_path(is_start: bool, word: &str, matches: &mut Vec<Pair>) {
+    if !is_start {
+        return;
+    }
     if let Ok(paths) = env::var("PATH") {
         for path in env::split_paths(&paths) {
             if let Ok(entries) = fs::read_dir(path) {