fix: read delete confirmation from tty when stdin is consumed (#642)

Closes #627

Author: replydev

Cargo.lock

@@ -34,7 +34,7 @@ rpassword = "7.4.0"
 data-encoding = "2.10.0"
 copypasta-ext = "0.4.4"
 zeroize = { version = "1.8.2", features = ["zeroize_derive"] }
-clap = { version = "4.5.60", features = ["derive"] }
+clap = { version = "4.6.0", features = ["derive"] }
 hmac = "0.12.1"
 sha1 = "0.10.6"
 sha2 = "0.10.9"

Cargo.toml

@@ -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;
@@ -24,34 +29,69 @@ pub struct DeleteArgs {
 
 impl SubcommandExecutor for DeleteArgs {
     fn run_command(self, mut otp_database: OTPDatabase) -> color_eyre::Result<OTPDatabase> {
+        if otp_database.elements_ref().is_empty() {
+            return Err(eyre!("There are no elements to delete"));
+        }
+
         let index_to_delete = self
             .index
             .and_then(|i| i.checked_sub(1))
+            // Match by issues or label if index filter is missing
             .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]: ",
-            index_to_delete + 1,
-            element.issuer,
-            element.label
-        );
-        io::stdout().flush()?;
+        if let Some(element) = otp_database.elements_ref().get(index_to_delete) {
+            print!(
+                "Are you sure you want to delete the {}th code ({}, {}) [Y,N]: ",
+                index_to_delete + 1,
+                element.issuer,
+                element.label
+            );
+            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);
-            Ok(otp_database)
+            if output.trim().eq_ignore_ascii_case("y") {
+                otp_database.delete_element(index_to_delete);
+                Ok(otp_database)
+            } else {
+                Err(eyre!("Operation interrupt by the user"))
+            }
         } else {
-            Err(eyre!("Operation interrupt by the user"))
+            Err(eyre!("Missing {}th code to delete", index_to_delete + 1))
         }
     }
 }
 
+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,