cirious_codex_term 0.2.1

use std::io::{self, Write};

/// A utility struct for manipulating the terminal cursor.
///
/// Provides methods to move the cursor, change its visibility, and
/// save/restore its position using ANSI escape sequences.
///
/// # Examples
///
/// ```rust,no_run
/// use cirious_codex_term::Cursor;
/// use std::io::stdout;
///
/// let mut writer = stdout();
/// Cursor::set_position(&mut writer, 10, 5);
/// Cursor::hide(&mut writer);
/// Cursor::flush(&mut writer);
/// ```
#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
pub struct Cursor;

impl Cursor {
  /// Moves the cursor up by the specified number of lines.
  ///
  /// # Errors
  /// Returns an `std::io::Result` if writing to the terminal fails.
  pub fn up<W: Write>(writer: &mut W, n: u16) -> io::Result<()> {
    write!(writer, "\x1b[{n}A")
  }

  /// Moves the cursor down by the specified number of lines.
  ///
  /// # Errors
  /// Returns an `std::io::Result` if writing to the terminal fails.
  pub fn down<W: Write>(writer: &mut W, n: u16) -> io::Result<()> {
    write!(writer, "\x1b[{n}B")
  }

  /// Moves the cursor right by the specified number of columns.
  ///
  /// # Errors
  /// Returns an `std::io::Result` if writing to the terminal fails.
  pub fn right<W: Write>(writer: &mut W, n: u16) -> io::Result<()> {
    write!(writer, "\x1b[{n}C")
  }

  /// Moves the cursor left by the specified number of columns.
  ///
  /// # Errors
  /// Returns an `std::io::Result` if writing to the terminal fails.
  pub fn left<W: Write>(writer: &mut W, n: u16) -> io::Result<()> {
    write!(writer, "\x1b[{n}D")
  }

  /// Sets the absolute position of the cursor.
  ///
  /// `x` represents the column (1-based) and `y` represents the row (1-based).
  ///
  /// # Errors
  /// Returns an `std::io::Result` if writing to the terminal fails.
  pub fn set_position<W: Write>(writer: &mut W, x: u16, y: u16) -> io::Result<()> {
    write!(writer, "\x1b[{y};{x}H")
  }

  /// Hides the terminal cursor.
  ///
  /// # Errors
  /// Returns an `std::io::Result` if writing to the terminal fails.
  pub fn hide<W: Write>(writer: &mut W) -> io::Result<()> {
    writer.write_all(b"\x1b[?25l")
  }

  /// Shows the terminal cursor.
  ///
  /// # Errors
  /// Returns an `std::io::Result` if writing to the terminal fails.
  pub fn show<W: Write>(writer: &mut W) -> io::Result<()> {
    writer.write_all(b"\x1b[?25h")
  }

  /// Saves the current cursor position.
  ///
  /// # Errors
  /// Returns an `std::io::Result` if writing to the terminal fails.
  pub fn save_position<W: Write>(writer: &mut W) -> io::Result<()> {
    writer.write_all(b"\x1b[s")
  }

  /// Restores the cursor to the last saved position.
  ///
  /// # Errors
  /// Returns an `std::io::Result` if writing to the terminal fails.
  pub fn restore_position<W: Write>(writer: &mut W) -> io::Result<()> {
    writer.write_all(b"\x1b[u")
  }

  /// Flushes the standard output buffer.
  ///
  /// Terminal escape sequences are buffered by default. Calling this
  /// ensures that all cursor movements are executed immediately.
  ///
  /// # Errors
  /// Returns an `std::io::Result` if writing to the terminal fails.
  pub fn flush<W: Write>(writer: &mut W) -> io::Result<()> {
    writer.flush()
  }
}

#[cfg(test)]
mod tests {
  use super::*;

  #[test]
  fn test_cursor_movements_generate_correct_ansi() -> Result<(), Box<dyn std::error::Error>> {
    let mut buffer = Vec::new();

    // Testamos se a string ANSI gerada está correta
    Cursor::set_position(&mut buffer, 10, 5)?;
    assert_eq!(buffer, b"\x1b[5;10H");

    buffer.clear(); // Limpa o buffer para o próximo teste

    Cursor::up(&mut buffer, 2)?;
    // Nota: O flush() vai acontecer dentro da função se você o adicionou lá!
    assert_eq!(buffer, b"\x1b[2A");
    Ok(())
  }
}