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use core::hash::{Hash, Hasher};
use std::iter::FromIterator;

// allowing this since PartialEq equality here still implies hash equality
#[allow(clippy::derived_hash_with_manual_eq)]
#[derive(Clone, Debug, Ord, Eq, PartialEq, PartialOrd)]
pub struct OrderedHashMap<K, V>(linked_hash_map::LinkedHashMap<K, V>)
where
    K: Hash + Eq + Ord;

impl<K, V> Default for OrderedHashMap<K, V>
where
    K: Hash + Eq + Ord,
{
    fn default() -> Self {
        Self::new()
    }
}

impl<K, V> std::ops::Deref for OrderedHashMap<K, V>
where
    K: Hash + Eq + Ord,
{
    type Target = linked_hash_map::LinkedHashMap<K, V>;

    fn deref(&self) -> &Self::Target {
        &self.0
    }
}

impl<K, V> std::ops::DerefMut for OrderedHashMap<K, V>
where
    K: Hash + Eq + Ord,
{
    fn deref_mut(&mut self) -> &mut Self::Target {
        &mut self.0
    }
}

impl<K, V> OrderedHashMap<K, V>
where
    K: Hash + Eq + Ord,
{
    pub fn new() -> Self {
        Self(linked_hash_map::LinkedHashMap::new())
    }

    pub fn take(self) -> linked_hash_map::LinkedHashMap<K, V> {
        self.0
    }
}

#[allow(clippy::derived_hash_with_manual_eq)]
impl<K, V> Hash for OrderedHashMap<K, V>
where
    K: Hash + Eq + Ord,
    V: Hash,
{
    fn hash<H: Hasher>(&self, h: &mut H) {
        self.0.hash(h);
    }
}

impl<K, V> serde::Serialize for OrderedHashMap<K, V>
where
    K: Hash + Eq + Ord + serde::Serialize,
    V: serde::Serialize,
{
    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
    where
        S: serde::Serializer,
    {
        let map = self.iter().collect::<std::collections::BTreeMap<_, _>>();
        map.serialize(serializer)
    }
}

impl<'de, K, V> serde::de::Deserialize<'de> for OrderedHashMap<K, V>
where
    K: Hash + Eq + Ord + serde::Deserialize<'de>,
    V: serde::Deserialize<'de>,
{
    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
    where
        D: serde::de::Deserializer<'de>,
    {
        let map = <std::collections::BTreeMap<_, _> as serde::de::Deserialize>::deserialize(
            deserializer,
        )?;
        Ok(Self(map.into_iter().collect()))
    }
}

impl<K, V> schemars::JsonSchema for OrderedHashMap<K, V>
where
    K: Hash + Eq + Ord + schemars::JsonSchema,
    V: schemars::JsonSchema,
{
    fn schema_name() -> String {
        format!("OrderedHashMap<{}, {}>", K::schema_name(), V::schema_name())
    }
    fn json_schema(gen: &mut schemars::gen::SchemaGenerator) -> schemars::schema::Schema {
        std::collections::BTreeMap::<K, V>::json_schema(gen)
    }
    fn is_referenceable() -> bool {
        std::collections::BTreeMap::<K, V>::is_referenceable()
    }
}

impl<K, V> FromIterator<(K, V)> for OrderedHashMap<K, V>
where
    K: Hash + Eq + Ord,
{
    fn from_iter<T: IntoIterator<Item = (K, V)>>(iter: T) -> Self {
        Self(linked_hash_map::LinkedHashMap::from_iter(iter))
    }
}