use crate::game::Game;

/// A Plugin is something you can add to a `Game` that can be used to define systems, or spawn initial entities.
pub trait Plugin {
    /// Setup this plugin. This runs before the game has started
    fn setup(&self, game: &mut Game);
}

impl<P> Plugin for P
    where P: Fn(&mut Game)
{
    fn setup(&self, game: &mut Game) {
        self(game);
    }
}

/// Represents a set of plugins that will be executed in order they are supplied.
#[derive(Default)]
pub struct PluginSet {
    /// A set of plugins that will be executed in order
    pub plugins: Vec<Box<dyn Plugin>>,
}

impl PluginSet {
    pub fn new() -> Self {
        Self::default()
    }

    pub fn add_plugin<P>(&mut self, plugin: P) -> &mut Self
    where
        P: Plugin + 'static
    {
        self.plugins.push(Box::new(plugin));

        self
    }
}

impl Plugin for PluginSet {
    fn setup(&self, game: &mut Game) {
        for plugin in self.plugins.iter() {
            plugin.setup(game);
        }
    }
}

// Macro used for implementing PluginSet for tuples
macro_rules! impl_tuple_plugin_set {
    ( $(($name: ident, $index: tt))+ ) => (
        impl<$($name: Plugin + 'static),+> From<($($name,)+)> for PluginSet {
            fn from(value: ($($name,)+)) -> Self {
                let plugins = vec![$(Box::new(value.$index) as Box<(dyn Plugin + 'static)>),+];
        
                Self {
                    plugins,
                }
            }
        }
    );
}

impl_tuple_plugin_set! { (C0, 0) }
impl_tuple_plugin_set! { (C0, 0) (C1, 1) }
impl_tuple_plugin_set! { (C0, 0) (C1, 1) (C2, 2) }
impl_tuple_plugin_set! { (C0, 0) (C1, 1) (C2, 2) (C3, 3) }
impl_tuple_plugin_set! { (C0, 0) (C1, 1) (C2, 2) (C3, 3) (C4, 4) }
impl_tuple_plugin_set! { (C0, 0) (C1, 1) (C2, 2) (C3, 3) (C4, 4) (C5, 5) }
impl_tuple_plugin_set! { (C0, 0) (C1, 1) (C2, 2) (C3, 3) (C4, 4) (C5, 5) (C6, 6) }
impl_tuple_plugin_set! { (C0, 0) (C1, 1) (C2, 2) (C3, 3) (C4, 4) (C5, 5) (C6, 6) (C7, 7) }
impl_tuple_plugin_set! { (C0, 0) (C1, 1) (C2, 2) (C3, 3) (C4, 4) (C5, 5) (C6, 6) (C7, 7) (C8, 8) }
impl_tuple_plugin_set! { (C0, 0) (C1, 1) (C2, 2) (C3, 3) (C4, 4) (C5, 5) (C6, 6) (C7, 7) (C8, 8) (C9, 9) }
impl_tuple_plugin_set! { (C0, 0) (C1, 1) (C2, 2) (C3, 3) (C4, 4) (C5, 5) (C6, 6) (C7, 7) (C8, 8) (C9, 9) (C10, 10) }
impl_tuple_plugin_set! { (C0, 0) (C1, 1) (C2, 2) (C3, 3) (C4, 4) (C5, 5) (C6, 6) (C7, 7) (C8, 8) (C9, 9) (C10, 10) (C11, 11) }
impl_tuple_plugin_set! { (C0, 0) (C1, 1) (C2, 2) (C3, 3) (C4, 4) (C5, 5) (C6, 6) (C7, 7) (C8, 8) (C9, 9) (C10, 10) (C11, 11) (C12, 12) }
impl_tuple_plugin_set! { (C0, 0) (C1, 1) (C2, 2) (C3, 3) (C4, 4) (C5, 5) (C6, 6) (C7, 7) (C8, 8) (C9, 9) (C10, 10) (C11, 11) (C12, 12) (C13, 13) }
impl_tuple_plugin_set! { (C0, 0) (C1, 1) (C2, 2) (C3, 3) (C4, 4) (C5, 5) (C6, 6) (C7, 7) (C8, 8) (C9, 9) (C10, 10) (C11, 11) (C12, 12) (C13, 13) (C14, 14) }