//! Implementations of serialization for structures found in liballoc

use crate::{Decodable, Decoder, Encodable, Encoder};
use smallvec::{Array, SmallVec};
use std::collections::{BTreeMap, BTreeSet, HashMap, HashSet, LinkedList, VecDeque};
use std::hash::{BuildHasher, Hash};
use std::rc::Rc;
use std::sync::Arc;
use thin_vec::ThinVec;

impl<S: Encoder, A: Array<Item: Encodable<S>>> Encodable<S> for SmallVec<A> {
    fn encode(&self, s: &mut S) {
        let slice: &[A::Item] = self;
        slice.encode(s);
    }
}

impl<D: Decoder, A: Array<Item: Decodable<D>>> Decodable<D> for SmallVec<A> {
    fn decode(d: &mut D) -> SmallVec<A> {
        let len = d.read_usize();
        (0..len).map(|_| Decodable::decode(d)).collect()
    }
}

impl<S: Encoder, T: Encodable<S>> Encodable<S> for ThinVec<T> {
    fn encode(&self, s: &mut S) {
        self.as_slice().encode(s);
    }
}

impl<D: Decoder, T: Decodable<D>> Decodable<D> for ThinVec<T> {
    fn decode(d: &mut D) -> ThinVec<T> {
        let len = d.read_usize();
        (0..len).map(|_| Decodable::decode(d)).collect()
    }
}

impl<S: Encoder, T: Encodable<S>> Encodable<S> for LinkedList<T> {
    fn encode(&self, s: &mut S) {
        s.emit_usize(self.len());
        for e in self.iter() {
            e.encode(s);
        }
    }
}

impl<D: Decoder, T: Decodable<D>> Decodable<D> for LinkedList<T> {
    fn decode(d: &mut D) -> LinkedList<T> {
        let len = d.read_usize();
        (0..len).map(|_| Decodable::decode(d)).collect()
    }
}

impl<S: Encoder, T: Encodable<S>> Encodable<S> for VecDeque<T> {
    fn encode(&self, s: &mut S) {
        s.emit_usize(self.len());
        for e in self.iter() {
            e.encode(s);
        }
    }
}

impl<D: Decoder, T: Decodable<D>> Decodable<D> for VecDeque<T> {
    fn decode(d: &mut D) -> VecDeque<T> {
        let len = d.read_usize();
        (0..len).map(|_| Decodable::decode(d)).collect()
    }
}

impl<S: Encoder, K, V> Encodable<S> for BTreeMap<K, V>
where
    K: Encodable<S> + PartialEq + Ord,
    V: Encodable<S>,
{
    fn encode(&self, e: &mut S) {
        e.emit_usize(self.len());
        for (key, val) in self.iter() {
            key.encode(e);
            val.encode(e);
        }
    }
}

impl<D: Decoder, K, V> Decodable<D> for BTreeMap<K, V>
where
    K: Decodable<D> + PartialEq + Ord,
    V: Decodable<D>,
{
    fn decode(d: &mut D) -> BTreeMap<K, V> {
        let len = d.read_usize();
        let mut map = BTreeMap::new();
        for _ in 0..len {
            let key = Decodable::decode(d);
            let val = Decodable::decode(d);
            map.insert(key, val);
        }
        map
    }
}

impl<S: Encoder, T> Encodable<S> for BTreeSet<T>
where
    T: Encodable<S> + PartialEq + Ord,
{
    fn encode(&self, s: &mut S) {
        s.emit_usize(self.len());
        for e in self.iter() {
            e.encode(s);
        }
    }
}

impl<D: Decoder, T> Decodable<D> for BTreeSet<T>
where
    T: Decodable<D> + PartialEq + Ord,
{
    fn decode(d: &mut D) -> BTreeSet<T> {
        let len = d.read_usize();
        let mut set = BTreeSet::new();
        for _ in 0..len {
            set.insert(Decodable::decode(d));
        }
        set
    }
}

impl<E: Encoder, K, V, S> Encodable<E> for HashMap<K, V, S>
where
    K: Encodable<E> + Eq,
    V: Encodable<E>,
    S: BuildHasher,
{
    fn encode(&self, e: &mut E) {
        e.emit_usize(self.len());
        for (key, val) in self.iter() {
            key.encode(e);
            val.encode(e);
        }
    }
}

impl<D: Decoder, K, V, S> Decodable<D> for HashMap<K, V, S>
where
    K: Decodable<D> + Hash + Eq,
    V: Decodable<D>,
    S: BuildHasher + Default,
{
    fn decode(d: &mut D) -> HashMap<K, V, S> {
        let len = d.read_usize();
        let state = Default::default();
        let mut map = HashMap::with_capacity_and_hasher(len, state);
        for _ in 0..len {
            let key = Decodable::decode(d);
            let val = Decodable::decode(d);
            map.insert(key, val);
        }
        map
    }
}

impl<E: Encoder, T, S> Encodable<E> for HashSet<T, S>
where
    T: Encodable<E> + Eq,
    S: BuildHasher,
{
    fn encode(&self, s: &mut E) {
        s.emit_usize(self.len());
        for e in self.iter() {
            e.encode(s);
        }
    }
}

impl<D: Decoder, T, S> Decodable<D> for HashSet<T, S>
where
    T: Decodable<D> + Hash + Eq,
    S: BuildHasher + Default,
{
    fn decode(d: &mut D) -> HashSet<T, S> {
        let len = d.read_usize();
        let state = Default::default();
        let mut set = HashSet::with_capacity_and_hasher(len, state);
        for _ in 0..len {
            set.insert(Decodable::decode(d));
        }
        set
    }
}

impl<E: Encoder, K, V, S> Encodable<E> for indexmap::IndexMap<K, V, S>
where
    K: Encodable<E> + Hash + Eq,
    V: Encodable<E>,
    S: BuildHasher,
{
    fn encode(&self, e: &mut E) {
        e.emit_usize(self.len());
        for (key, val) in self.iter() {
            key.encode(e);
            val.encode(e);
        }
    }
}

impl<D: Decoder, K, V, S> Decodable<D> for indexmap::IndexMap<K, V, S>
where
    K: Decodable<D> + Hash + Eq,
    V: Decodable<D>,
    S: BuildHasher + Default,
{
    fn decode(d: &mut D) -> indexmap::IndexMap<K, V, S> {
        let len = d.read_usize();
        let state = Default::default();
        let mut map = indexmap::IndexMap::with_capacity_and_hasher(len, state);
        for _ in 0..len {
            let key = Decodable::decode(d);
            let val = Decodable::decode(d);
            map.insert(key, val);
        }
        map
    }
}

impl<E: Encoder, T, S> Encodable<E> for indexmap::IndexSet<T, S>
where
    T: Encodable<E> + Hash + Eq,
    S: BuildHasher,
{
    fn encode(&self, s: &mut E) {
        s.emit_usize(self.len());
        for e in self.iter() {
            e.encode(s);
        }
    }
}

impl<D: Decoder, T, S> Decodable<D> for indexmap::IndexSet<T, S>
where
    T: Decodable<D> + Hash + Eq,
    S: BuildHasher + Default,
{
    fn decode(d: &mut D) -> indexmap::IndexSet<T, S> {
        let len = d.read_usize();
        let state = Default::default();
        let mut set = indexmap::IndexSet::with_capacity_and_hasher(len, state);
        for _ in 0..len {
            set.insert(Decodable::decode(d));
        }
        set
    }
}

impl<E: Encoder, T: Encodable<E>> Encodable<E> for Rc<[T]> {
    fn encode(&self, s: &mut E) {
        let slice: &[T] = self;
        slice.encode(s);
    }
}

impl<D: Decoder, T: Decodable<D>> Decodable<D> for Rc<[T]> {
    fn decode(d: &mut D) -> Rc<[T]> {
        let vec: Vec<T> = Decodable::decode(d);
        vec.into()
    }
}

impl<E: Encoder, T: Encodable<E>> Encodable<E> for Arc<[T]> {
    fn encode(&self, s: &mut E) {
        let slice: &[T] = self;
        slice.encode(s);
    }
}

impl<D: Decoder, T: Decodable<D>> Decodable<D> for Arc<[T]> {
    fn decode(d: &mut D) -> Arc<[T]> {
        let vec: Vec<T> = Decodable::decode(d);
        vec.into()
    }
}