fix: read delete confirmation from tty when stdin is consumed

src/arguments/delete.rs

@@ -1,4 +1,9 @@
-use std::io::{self, Write};
+use std::io::{self, BufRead, Write};
+
+#[cfg(unix)]
+use std::fs::File;
+#[cfg(windows)]
+use std::fs::OpenOptions;
 
 use clap::Args;
 use color_eyre::eyre::eyre;
@@ -30,8 +35,6 @@ impl SubcommandExecutor for DeleteArgs {
             .or_else(|| get_first_matching_element(&otp_database, &self))
             .ok_or(eyre!("No code has been found using the given arguments"))?;
 
-        let mut output = String::with_capacity(1);
-
         let element = otp_database.elements_ref().get(index_to_delete).unwrap();
         print!(
             "Are you sure you want to delete the {}th code ({}, {}) [Y,N]: ",
@@ -41,7 +44,7 @@ impl SubcommandExecutor for DeleteArgs {
         );
         io::stdout().flush()?;
 
-        io::stdin().read_line(&mut output)?;
+        let output = read_confirmation_line()?;
 
         if output.trim().eq_ignore_ascii_case("y") {
             otp_database.delete_element(index_to_delete);
@@ -52,6 +55,35 @@ impl SubcommandExecutor for DeleteArgs {
     }
 }
 
+fn read_confirmation_line() -> color_eyre::Result<String> {
+    let mut output = String::with_capacity(1);
+
+    if io::stdin().read_line(&mut output)? > 0 {
+        return Ok(output);
+    }
+
+    #[cfg(unix)]
+    {
+        output.clear();
+        let mut tty = io::BufReader::new(File::open("/dev/tty")?);
+        tty.read_line(&mut output)?;
+        return Ok(output);
+    }
+
+    #[cfg(windows)]
+    {
+        output.clear();
+        let mut tty = io::BufReader::new(OpenOptions::new().read(true).open("CONIN$")?);
+        tty.read_line(&mut output)?;
+        return Ok(output);
+    }
+
+    #[allow(unreachable_code)]
+    Err(eyre!(
+        "Unable to read confirmation answer from standard input or terminal"
+    ))
+}
+
 fn get_first_matching_element(
     otp_database: &OTPDatabase,
     delete_args: &DeleteArgs,