// Copyright 2020 Sergiusz 'q3k' Bazanski <q3k@q3k.org>
//
// This file is part of Abrasion.
//
// Abrasion is free software: you can redistribute it and/or modify it under
// the terms of the GNU General Public License as published by the Free
// Software Foundation, version 3.
//
// Abrasion is distributed in the hope that it will be useful, but WITHOUT ANY
// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
// FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
// details.
//
// You should have received a copy of the GNU General Public License along with
// Abrasion.  If not, see <https://www.gnu.org/licenses/>.

use std::cmp::PartialEq;

/// A map from ResourceID to Vec<T>, useful for building up information about
/// a scene. This implementation is currently naive, but is pretty fast
/// compared to a HashMap as it performs no hashing - just uses ResourceIDs.
/// In the future, this could be ported over to a tree implemention from the
/// current naive vector-based implementation.
pub struct ResourceMap<K, V> {
    pub resources: Vec<(K, Vec<V>)>,
}

impl<K: PartialEq, V> ResourceMap<K, V> {
    pub fn new() -> Self {
        Self {
            resources: vec![],
        }
    }

    /// Add to a Resource's corresponding vector, creating an empty one first
    /// if needed.
    pub fn add(&mut self, k: K, t: V) {
        for (k2, v) in self.resources.iter_mut() {
            if *k2 == k {
                v.push(t);
                return;
            }
        }

        self.resources.push((k, vec![t]));
    }
}