//! Create choices using radio buttons.
use crate::Color;

/// A circular button representing a choice.
///
/// # Example
/// ```
/// use iced_core::Radio;
///
/// #[derive(Debug, Clone, Copy, PartialEq, Eq)]
/// pub enum Choice {
///     A,
///     B,
/// }
///
/// #[derive(Debug, Clone, Copy)]
/// pub enum Message {
///     RadioSelected(Choice),
/// }
///
/// let selected_choice = Some(Choice::A);
///
/// Radio::new(Choice::A, "This is A", selected_choice, Message::RadioSelected);
///
/// Radio::new(Choice::B, "This is B", selected_choice, Message::RadioSelected);
/// ```
///
/// ![Radio buttons drawn by Coffee's renderer](https://github.com/hecrj/coffee/blob/bda9818f823dfcb8a7ad0ff4940b4d4b387b5208/images/ui/radio.png?raw=true)
pub struct Radio<Message> {
    /// Whether the radio button is selected or not
    pub is_selected: bool,

    /// The message to produce when the radio button is clicked
    pub on_click: Message,

    /// The label of the radio button
    pub label: String,

    /// The color of the label
    pub label_color: Option<Color>,
}

impl<Message> std::fmt::Debug for Radio<Message>
where
    Message: std::fmt::Debug,
{
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        f.debug_struct("Radio")
            .field("is_selected", &self.is_selected)
            .field("on_click", &self.on_click)
            .field("label", &self.label)
            .field("label_color", &self.label_color)
            .finish()
    }
}

impl<Message> Radio<Message> {
    /// Creates a new [`Radio`] button.
    ///
    /// It expects:
    ///   * the value related to the [`Radio`] button
    ///   * the label of the [`Radio`] button
    ///   * the current selected value
    ///   * a function that will be called when the [`Radio`] is selected. It
    ///   receives the value of the radio and must produce a `Message`.
    ///
    /// [`Radio`]: struct.Radio.html
    pub fn new<F, V>(value: V, label: &str, selected: Option<V>, f: F) -> Self
    where
        V: Eq + Copy,
        F: 'static + Fn(V) -> Message,
    {
        Radio {
            is_selected: Some(value) == selected,
            on_click: f(value),
            label: String::from(label),
            label_color: None,
        }
    }

    /// Sets the `Color` of the label of the [`Radio`].
    ///
    /// [`Radio`]: struct.Radio.html
    pub fn label_color<C: Into<Color>>(mut self, color: C) -> Self {
        self.label_color = Some(color.into());
        self
    }
}