//! # [Node] is a struct representing a node in the graph,
//! --- which has a generic data field and a list of [EdgeID]s.
//!
//! A [NodeID] is a key to the node in the slotmap.
//!
//! # Why is there no "NodeTrait"?
//!
//! The [Node] struct is very simple and doesn't need a trait.
//! If you want to add more functionality or data to the Node you can probably just add it to the data field, or add a node as a field to your custom type.

use super::*;
use slotmap::{new_key_type, KeyData};

new_key_type! {
    /// A key to the node in the slotmap.
    pub struct NodeID;
}

impl NodeID {
    pub fn to_u64(&self) -> u64 {
        self.0.as_ffi()
    }
    pub fn from_u64(id: u64) -> Self {
        NodeID::from(KeyData::from_ffi(id))
    }
}


/* -------------------------------------------------------------------------- */
/*                                    Node                                    */
/* -------------------------------------------------------------------------- */

/// # A struct representing a node/vertex in the graph.
/// Has a generic data field and a list of [EdgeID]s.
///
/// A [NodeID] is a key to the node in the slotmap.
///
/// ## Why is there no "NodeTrait"?
///
/// The [Node] struct is very simple and doesn't need a trait.
/// If you want to add more functionality or data to the Node you can probably just add it to the data field, or add a node as a field to your custom type.
#[derive(Clone)]
#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
#[cfg_attr(feature = "specta", derive(specta::Type))]
pub struct Node<T: Clone> {
    pub id: NodeID,
    pub data: T,
    pub connections: Vec<EdgeID>,
}

/// Implements PartialEQ for Node<T> so only the ID is used for comparison.
impl<T: Clone> PartialEq for Node<T> {
    fn eq(&self, other: &Self) -> bool {
        self.id == other.id
    }
}

/// Implements Hash for Node<T> so only the ID is used for hashing.
impl<T: std::hash::Hash> std::hash::Hash for Node<T>
where
    T: Clone,
{
    fn hash<H: std::hash::Hasher>(&self, ra_expand_state: &mut H) {
        self.id.hash(ra_expand_state);
    }
}


/* ---------------------------------- Debug --------------------------------- */

impl<T: Clone + fmt::Debug> fmt::Debug for Node<T> {
    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
        write!(
            f,
            "Node {{ id: {:#?}, data: {:#?}, connections: {:#?} }}",
            self.id, self.data, self.connections
        )
    }
}

impl<T: Clone> Node<T> {
    pub fn new(id: NodeID, data: T) -> Node<T> {
        Node {
            id,
            data,
            connections: Vec::new(),
        }
    }

    pub fn add_connection(&mut self, edge: EdgeID) {
        self.connections.push(edge);
    }
}

#[cfg(feature = "specta")]
const _: () = {
    const SID: specta::SpectaID = specta::internal::construct::sid(
        "NodeID",
        concat!("::", module_path!(), ":", line!(), ":", column!()),
    );
    const IMPL_LOCATION: specta::ImplLocation =
        specta::internal::construct::impl_location(concat!(file!(), ":", line!(), ":", column!()));
    const DEFINITION_GENERICS: &[specta::DataType] = &[];

    #[automatically_derived]
    impl specta::Type for NodeID {
        fn inline(
            type_map: &mut specta::TypeMap,
            generics: &[specta::DataType],
        ) -> specta::DataType {
            specta::DataType::Struct(specta::internal::construct::r#struct(
                "NodeID".into(),
                Some(SID),
                vec![],
                specta::internal::construct::struct_named(
                    vec![
                        (
                            "idx".into(),
                            specta::internal::construct::field(
                                false,
                                false,
                                None,
                                "".into(),
                                Some({
                                    let ty = <u32 as specta::Type>::reference(type_map, &[]).inner;
                                    ty
                                }),
                            ),
                        ),
                        (
                            "version".into(),
                            specta::internal::construct::field(
                                false,
                                false,
                                None,
                                "".into(),
                                Some({
                                    let ty = <u32 as specta::Type>::reference(type_map, &[]).inner;
                                    ty
                                }),
                            ),
                        ),
                    ],
                    None,
                ),
            ))
        }
        fn definition(type_map: &mut specta::TypeMap) -> specta::DataType {
            Self::inline(type_map, &DEFINITION_GENERICS)
        }
        fn reference(
            type_map: &mut specta::TypeMap,
            generics: &[specta::DataType],
        ) -> specta::reference::Reference {
            {
                let generics: &[specta::DataType] = &[];
                specta::reference::reference::<Self>(
                    type_map,
                    specta::internal::construct::data_type_reference("NodeID".into(), SID, vec![]),
                )
            }
        }
    }
    #[automatically_derived]
    impl specta::NamedType for NodeID {
        const SID: specta::SpectaID = SID;
        const IMPL_LOCATION: specta::ImplLocation = IMPL_LOCATION;
        fn named_data_type(
            type_map: &mut specta::TypeMap,
            generics: &[specta::DataType],
        ) -> specta::NamedDataType {
            specta::internal::construct::named_data_type(
                "NodeID".into(),
                "".into(),
                None,
                SID,
                IMPL_LOCATION,
                <Self as specta::Type>::inline(type_map, generics),
            )
        }
        fn definition_named_data_type(type_map: &mut specta::TypeMap) -> specta::NamedDataType {
            specta::internal::construct::named_data_type(
                "NodeID".into(),
                "".into(),
                None,
                SID,
                IMPL_LOCATION,
                <Self as specta::Type>::definition(type_map),
            )
        }
    }
    #[automatically_derived]
    impl specta::Flatten for NodeID {}
};