cli: add status command

Provides equivalent functionality to `yubico-piv-tool`

cli/src/terminal.rs

@@ -0,0 +1,165 @@
+//! Status messages
+
+use lazy_static::lazy_static;
+use std::io::{self, Write};
+use std::sync::Mutex;
+use termcolor::{Color, ColorChoice, ColorSpec, StandardStream, WriteColor};
+
+/// Print a success status message (in green if colors are enabled)
+#[macro_export]
+macro_rules! status_ok {
+    ($status:expr, $msg:expr) => {
+        $crate::terminal::Status::new()
+            .justified()
+            .bold()
+            .color(termcolor::Color::Green)
+            .status($status)
+            .print_stdout($msg);
+    };
+    ($status:expr, $fmt:expr, $($arg:tt)+) => {
+        $crate::status_ok!($status, format!($fmt, $($arg)+));
+    };
+}
+
+/// Print a warning status message (in yellow if colors are enabled)
+#[macro_export]
+macro_rules! status_warn {
+    ($msg:expr) => {
+        $crate::terminal::Status::new()
+            .bold()
+            .color(termcolor::Color::Yellow)
+            .status("warning:")
+            .print_stdout($msg);
+    };
+    ($fmt:expr, $($arg:tt)+) => {
+        $crate::status_warn!(format!($fmt, $($arg)+));
+    };
+}
+
+/// Print an error message (in red if colors are enabled)
+#[macro_export]
+macro_rules! status_err {
+    ($msg:expr) => {
+        $crate::terminal::Status::new()
+            .bold()
+            .color(termcolor::Color::Red)
+            .status("error:")
+            .print_stderr($msg);
+    };
+    ($fmt:expr, $($arg:tt)+) => {
+        $crate::status_err!(format!($fmt, $($arg)+));
+    };
+}
+
+lazy_static! {
+    /// Color configuration
+    static ref COLOR_CHOICE: Mutex<Option<ColorChoice>> = Mutex::new(None);
+
+    /// Standard output
+    pub static ref STDOUT: StandardStream = StandardStream::stdout(get_color_choice());
+
+    /// Standard error
+    pub static ref STDERR: StandardStream = StandardStream::stderr(get_color_choice());
+}
+
+/// Obtain the color configuration.
+///
+/// Panics if no configuration has been provided.
+fn get_color_choice() -> ColorChoice {
+    let choice = COLOR_CHOICE.lock().unwrap();
+    *choice
+        .as_ref()
+        .expect("terminal stream accessed before initialized!")
+}
+
+/// Set the color configuration.
+///
+/// Panics if the terminal has already been configured.
+pub(super) fn set_color_choice(color_choice: ColorChoice) {
+    let mut choice = COLOR_CHOICE.lock().unwrap();
+    assert!(choice.is_none(), "terminal colors already configured!");
+    *choice = Some(color_choice);
+}
+
+/// Status message builder
+#[derive(Clone, Debug, Default)]
+pub struct Status {
+    /// Should the status be justified?
+    justified: bool,
+
+    /// Should colors be bold?
+    bold: bool,
+
+    /// Color in which status should be displayed
+    color: Option<Color>,
+
+    /// Prefix of the status message (e.g. `Success`)
+    status: Option<String>,
+}
+
+impl Status {
+    /// Create a new status message with default settings
+    pub fn new() -> Self {
+        Self::default()
+    }
+
+    /// Justify status on display
+    pub fn justified(mut self) -> Self {
+        self.justified = true;
+        self
+    }
+
+    /// Make colors bold
+    pub fn bold(mut self) -> Self {
+        self.bold = true;
+        self
+    }
+
+    /// Set the colors used to display this message
+    pub fn color(mut self, c: Color) -> Self {
+        self.color = Some(c);
+        self
+    }
+
+    /// Set a status message to display
+    pub fn status<S>(mut self, msg: S) -> Self
+    where
+        S: ToString,
+    {
+        self.status = Some(msg.to_string());
+        self
+    }
+
+    /// Print the given message to stdout
+    pub fn print_stdout(self, msg: impl AsRef<str>) {
+        self.print(&*STDOUT, msg)
+            .expect("error printing to stdout!")
+    }
+
+    /// Print the given message to stderr
+    pub fn print_stderr(self, msg: impl AsRef<str>) {
+        self.print(&*STDERR, msg)
+            .expect("error printing to stderr!")
+    }
+
+    /// Print the given message
+    fn print(self, stream: &StandardStream, msg: impl AsRef<str>) -> Result<(), io::Error> {
+        let mut s = stream.lock();
+        s.reset()?;
+        s.set_color(ColorSpec::new().set_fg(self.color).set_bold(self.bold))?;
+
+        if let Some(status) = self.status {
+            if self.justified {
+                write!(s, "{:>12}", status)?;
+            } else {
+                write!(s, "{}", status)?;
+            }
+        }
+
+        s.reset()?;
+        writeln!(s, " {}", msg.as_ref())?;
+        s.flush()?;
+
+        Ok(())
+    }
+}