use std::sync::Mutex;
use std::collections::VecDeque;

/// Generic multiple-producer, multiple-consumer queue. Current implementation
/// has the required functionality, without all of the optimizations.
/// TODO: @Optimize
pub struct MpmcQueue<T: Sized> {
    queue: Mutex<VecDeque<T>>,
}

impl<T: Sized> MpmcQueue<T> {
    pub fn new() -> Self {
        Self::with_capacity(0)
    }

    pub fn with_capacity(capacity: usize) -> Self {
        Self{
            queue: Mutex::new(VecDeque::with_capacity(capacity)),
        }
    }

    pub fn push_back(&self, item: T) {
        let mut queue = self.queue.lock().unwrap();
        queue.push_back(item);
    }

    pub fn pop_front(&self) -> Option<T> {
        let mut queue = self.queue.lock().unwrap();
        return queue.pop_front();
    }
}