jsonld-core 0.25.0

use super::{Multiset, Objects};
use crate::{
    DefaultBuildHasher,
    Id,
    IndexMap,
    IndexedObject,
    object::{InvalidExpandedJson, TryFromJson, TryFromJsonObject},
};
use derive_where::derive_where;
use rdfx::vocabulary::VocabularyMut;
use std::hash::{Hash, Hasher};

/// Objects bound to a single property.
pub type PropertyObjects<T, B> = Multiset<IndexedObject<T, B>>;

/// Properties of a node object, and their associated objects.
#[derive(Debug, Clone)]
#[derive_where(PartialEq; T: Eq + Hash, B: Eq + Hash)]
pub struct Properties<T, B>(IndexMap<Id<T, B>, PropertyObjects<T, B>>);

impl<T: Eq + Hash, B: Eq + Hash> Eq for Properties<T, B> {}

impl<T, B> Default for Properties<T, B> {
    fn default() -> Self {
        Self::new()
    }
}

impl<T, B> Properties<T, B> {
    /// Creates an empty map.
    #[must_use]
    pub fn new() -> Self {
        Self(IndexMap::with_hasher(DefaultBuildHasher::default()))
    }

    /// Returns the number of properties.
    #[inline(always)]
    #[must_use]
    pub fn len(&self) -> usize {
        self.0.len()
    }

    /// Checks if there are no defined properties.
    #[inline(always)]
    #[must_use]
    pub fn is_empty(&self) -> bool {
        self.0.is_empty()
    }

    /// Returns an iterator over the properties and their associated objects.
    #[inline(always)]
    #[must_use]
    pub fn iter(&self) -> Iter<'_, T, B> {
        Iter { inner: self.0.iter() }
    }

    /// Returns an iterator over the properties with a mutable reference to their associated objects.
    #[inline(always)]
    pub fn iter_mut(&mut self) -> IterMut<'_, T, B> {
        self.0.iter_mut()
    }

    /// Removes all properties.
    #[inline(always)]
    pub fn clear(&mut self) {
        self.0.clear();
    }
}

impl<T: Eq + Hash, B: Eq + Hash> Properties<T, B> {
    /// Checks if the given property is associated to any object.
    #[inline(always)]
    pub fn contains<Q: ?Sized + Hash + indexmap::Equivalent<Id<T, B>>>(&self, prop: &Q) -> bool {
        self.0.get(prop).is_some()
    }

    /// Returns an iterator over all the objects associated to the given property.
    #[inline(always)]
    pub fn get<Q: ?Sized + Hash + indexmap::Equivalent<Id<T, B>>>(&self, prop: &Q) -> Objects<'_, T, B> {
        match self.0.get(prop) {
            Some(values) => Objects::new(Some(values.iter())),
            None => Objects::new(None),
        }
    }

    /// Returns one of the objects associated with the given property.
    ///
    /// If multiple objects are associated with it, there is no guarantee on
    /// which one is returned.
    #[inline(always)]
    pub fn get_any<Q: ?Sized + Hash + indexmap::Equivalent<Id<T, B>>>(&self, prop: &Q) -> Option<&IndexedObject<T, B>> {
        match self.0.get(prop) {
            Some(values) => values.iter().next(),
            None => None,
        }
    }

    /// Associate the given object to the node through the given property with metadata.
    #[inline(always)]
    pub fn insert(&mut self, prop: Id<T, B>, value: IndexedObject<T, B>) {
        if let Some(node_values) = self.0.get_mut(&prop) {
            node_values.insert(value);
        } else {
            self.0.insert(prop, Multiset::singleton(value));
        }
    }

    /// Associate the given object to the node through the given property, unless it is already.
    #[inline(always)]
    pub fn insert_unique(&mut self, prop: Id<T, B>, value: IndexedObject<T, B>) {
        if let Some(node_values) = self.0.get_mut(&prop) {
            if node_values.iter().all(|v| !v.equivalent(&value)) {
                node_values.insert(value);
            }
        } else {
            self.0.insert(prop, Multiset::singleton(value));
        }
    }

    /// Associate all the given objects to the node through the given property.
    #[inline(always)]
    pub fn insert_all<Objects: IntoIterator<Item = IndexedObject<T, B>>>(&mut self, prop: Id<T, B>, values: Objects) {
        if let Some(node_values) = self.0.get_mut(&prop) {
            node_values.extend(values);
        } else {
            // Fast path for the common single-value case: skip the
            // `FromIterator` collect and build a singleton `Multiset` directly.
            let mut iter = values.into_iter();
            match (iter.next(), iter.size_hint()) {
                (Some(first), (0, Some(0))) => {
                    self.0.insert(prop, Multiset::singleton(first));
                }
                (Some(first), _) => {
                    let mut multiset: PropertyObjects<T, B> = Multiset::singleton(first);
                    multiset.extend(iter);
                    self.0.insert(prop, multiset);
                }
                (None, _) => {
                    self.0.insert(prop, Multiset::default());
                }
            }
        }
    }

    /// Associate all the given objects to the node through the given property, unless it is already.
    ///
    /// The [equivalence operator](crate::Object::equivalent) is used to remove equivalent objects.
    #[inline(always)]
    pub fn insert_all_unique<Objects: IntoIterator<Item = IndexedObject<T, B>>>(&mut self, prop: Id<T, B>, values: Objects) {
        if let Some(node_values) = self.0.get_mut(&prop) {
            for value in values {
                if node_values.iter().all(|v| !v.equivalent(&value)) {
                    node_values.insert(value);
                }
            }
        } else {
            let values = values.into_iter();
            let mut node_values: PropertyObjects<T, B> = Multiset::with_capacity(values.size_hint().0);
            for value in values {
                if node_values.iter().all(|v| !v.equivalent(&value)) {
                    node_values.insert(value);
                }
            }

            self.0.insert(prop, node_values);
        }
    }

    /// Binds `prop` to exactly `values`, discarding what was there.
    pub fn set(&mut self, prop: Id<T, B>, values: PropertyObjects<T, B>) {
        self.0.insert(prop, values);
    }

    /// Adds the given bindings, skipping objects already bound to their
    /// property.
    pub fn extend_unique<I, O>(&mut self, iter: I)
    where
        I: IntoIterator<Item = (Id<T, B>, O)>,
        O: IntoIterator<Item = IndexedObject<T, B>>,
    {
        for (prop, values) in iter {
            self.insert_all_unique(prop, values);
        }
    }

    /// Removes and returns all the values associated to the given property.
    #[inline(always)]
    pub fn remove<Q: ?Sized + Hash + indexmap::Equivalent<Id<T, B>>>(&mut self, prop: &Q) -> Option<PropertyObjects<T, B>> {
        self.0.shift_remove(prop)
    }
}

impl<T: Eq + Hash, B: Eq + Hash, O> FromIterator<(Id<T, B>, O)> for Properties<T, B>
where
    O: IntoIterator<Item = IndexedObject<T, B>>,
{
    fn from_iter<I: IntoIterator<Item = (Id<T, B>, O)>>(iter: I) -> Self {
        let mut result = Self::default();
        for (id, values) in iter {
            result.insert_all(id, values);
        }
        result
    }
}

impl<T: Eq + Hash, B: Eq + Hash> TryFromJson<T, B> for Properties<T, B> {
    fn try_from_json_in(vocabulary: &mut impl VocabularyMut<Iri = T, BlankId = B>, value: jstrict::Value) -> Result<Self, InvalidExpandedJson> {
        match value {
            jstrict::Value::Object(object) => Self::try_from_json_object_in(vocabulary, object),
            _ => Err(InvalidExpandedJson::InvalidObject),
        }
    }
}

impl<T: Eq + Hash, B: Eq + Hash> TryFromJsonObject<T, B> for Properties<T, B> {
    fn try_from_json_object_in(vocabulary: &mut impl VocabularyMut<Iri = T, BlankId = B>, object: jstrict::Object) -> Result<Self, InvalidExpandedJson> {
        let mut result = Self::new();

        for entry in object {
            let prop = Id::from_string_in(vocabulary, entry.key.to_string());
            let objects: Vec<IndexedObject<T, B>> = Vec::try_from_json_in(vocabulary, entry.value)?;
            result.insert_all(prop, objects);
        }

        Ok(result)
    }
}

impl<T: Hash, B: Hash> Hash for Properties<T, B> {
    #[inline(always)]
    fn hash<H: Hasher>(&self, h: &mut H) {
        crate::utils::hash_map(&self.0, h);
    }
}

impl<T: Eq + Hash, B: Eq + Hash> Extend<(Id<T, B>, Vec<IndexedObject<T, B>>)> for Properties<T, B> {
    fn extend<I>(&mut self, iter: I)
    where
        I: IntoIterator<Item = (Id<T, B>, Vec<IndexedObject<T, B>>)>,
    {
        for (prop, values) in iter {
            self.insert_all(prop, values);
        }
    }
}

/// Tuple type representing a binding in a node object,
/// associating a property to some objects.
pub type Binding<T, B> = (Id<T, B>, PropertyObjects<T, B>);

/// Tuple type representing a reference to a binding in a node object,
/// associating a property to some objects.
pub type BindingRef<'a, T, B> = (&'a Id<T, B>, &'a [IndexedObject<T, B>]);

/// Tuple type representing a mutable reference to a binding in a node object,
/// associating a property to some objects, with a mutable access to the objects.
pub type BindingMut<'a, T, B> = (&'a Id<T, B>, &'a mut PropertyObjects<T, B>);

impl<T, B> IntoIterator for Properties<T, B> {
    type Item = Binding<T, B>;
    type IntoIter = IntoIter<T, B>;

    #[inline(always)]
    fn into_iter(self) -> Self::IntoIter {
        self.0.into_iter()
    }
}

impl<'a, T, B> IntoIterator for &'a Properties<T, B> {
    type Item = BindingRef<'a, T, B>;
    type IntoIter = Iter<'a, T, B>;

    #[inline(always)]
    fn into_iter(self) -> Self::IntoIter {
        self.iter()
    }
}

impl<'a, T, B> IntoIterator for &'a mut Properties<T, B> {
    type Item = BindingMut<'a, T, B>;
    type IntoIter = IterMut<'a, T, B>;

    #[inline(always)]
    fn into_iter(self) -> Self::IntoIter {
        self.iter_mut()
    }
}

/// Iterator over the properties of a node.
///
/// It is created by the [`Properties::into_iter`] function.
pub type IntoIter<T, B> = indexmap::map::IntoIter<Id<T, B>, PropertyObjects<T, B>>;

/// Iterator over the properties of a node.
///
/// It is created by the [`Properties::iter`] function.
#[derive_where(Clone)]
pub struct Iter<'a, T, B> {
    inner: indexmap::map::Iter<'a, Id<T, B>, PropertyObjects<T, B>>,
}

impl<'a, T, B> Iterator for Iter<'a, T, B> {
    type Item = BindingRef<'a, T, B>;

    #[inline(always)]
    fn size_hint(&self) -> (usize, Option<usize>) {
        self.inner.size_hint()
    }

    #[inline(always)]
    fn next(&mut self) -> Option<Self::Item> {
        self.inner.next().map(|(property, objects)| (property, objects.as_slice()))
    }
}

impl<T, B> ExactSizeIterator for Iter<'_, T, B> {}

impl<T, B> std::iter::FusedIterator for Iter<'_, T, B> {}

/// Iterator over the properties of a node, giving a mutable reference
/// to the associated objects.
///
/// It is created by the [`Properties::iter_mut`] function.
pub type IterMut<'a, T, B> = indexmap::map::IterMut<'a, Id<T, B>, PropertyObjects<T, B>>;