exml 0.7.2

use std::{
    cell::RefCell,
    collections::HashMap,
    mem::replace,
    rc::{Rc, Weak},
    sync::Arc,
};

use crate::dom::node::NodeStrongRef;

use super::{
    DOMException, NodeType, check_no_modification_allowed_err,
    document::{Document, DocumentRef},
    node::{Node, NodeConnection, NodeRef, NodeWeakRef},
    user_data::{DOMUserData, OperationType, UserDataHandler},
};

/// Implementation of [ProcessingInstruction](https://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407/DOM3-Core.html#core-ID-1004215813)
/// interface on [1.5 Extended Interfaces: XML Module](https://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407/DOM3-Core.html#core-ID-E067D597)
pub struct ProcessingInstruction {
    /// [1.1.1 The DOM Structure Model](https://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407/DOM3-Core.html#core-ID-1590626202)
    /// - `Document`
    /// - `DocumentFragment`
    /// - `EntityReference`
    /// - `Element`
    /// - `Entity`
    parent_node: Option<NodeWeakRef>,
    // /// [1.1.1 The DOM Structure Model](https://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407/DOM3-Core.html#core-ID-1590626202)
    // /// - no children
    // first_child: Option<NodeRef>,
    // last_child: Option<NodeRef>,
    /// [1.1.1 The DOM Structure Model](https://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407/DOM3-Core.html#core-ID-1590626202)
    /// - `DocumentType`
    /// - `EntityReference`
    /// - `Element`
    /// - `ProcessingInstruction`
    /// - `Comment`
    /// - `Text`
    /// - `CDATASection`
    previous_sibling: Option<NodeWeakRef>,
    next_sibling: Option<NodeStrongRef>,
    owner_document: Weak<RefCell<Document>>,
    /// Implementation of `target` attribute for `ProcessingInstruction`.
    /// as same as `nodeName` for `Node`.
    target: Rc<str>,
    /// Implementation of `data` attribute for `ProcessingInstruction`.
    data: Option<Rc<str>>,

    user_data: Option<HashMap<String, (DOMUserData, Option<Arc<dyn UserDataHandler>>)>>,

    // 0      : read-only ?
    // 1 - 15 : unused
    flag: u16,
}

impl ProcessingInstruction {
    pub fn owner_document(&self) -> Option<DocumentRef> {
        self.owner_document.upgrade().map(From::from)
    }
}

/// Wrapper of `Rc<RefCell<ProcessingInstruction>>`.
#[derive(Clone)]
pub struct ProcessingInstructionRef(
    pub(super) Rc<RefCell<ProcessingInstruction>>,
    pub(super) DocumentRef,
);

impl ProcessingInstructionRef {
    /// Create new [`ProcessingInstructionRef`] whose ownerDocument is `doc`.
    ///
    /// This method does not validate `target`.
    pub(super) fn from_doc(doc: DocumentRef, target: Rc<str>, data: Option<Rc<str>>) -> Self {
        Self(
            Rc::new(RefCell::new(ProcessingInstruction {
                parent_node: None,
                previous_sibling: None,
                next_sibling: None,
                owner_document: Rc::downgrade(&doc.0),
                target,
                data,
                user_data: None,
                flag: 0,
            })),
            doc,
        )
    }

    /// Implementation of `data` attribute.
    ///
    /// # Specification
    /// ```text
    /// target of type DOMString, readonly
    ///     The target of this processing instruction. XML defines this as being the first
    ///     token following the markup that begins the processing instruction.
    /// ```
    pub fn target(&self) -> Rc<str> {
        self.0.borrow().target.clone()
    }

    /// Implementation of `data` attribute.
    ///
    /// # Specification
    /// ```text
    /// data of type DOMString
    ///     The content of this processing instruction. This is from the first non white
    ///     space character after the target to the character immediately preceding the ?>.
    pub fn data(&self) -> Option<Rc<str>> {
        self.0.borrow().data.clone()
    }

    /// Implementation of `data` attribute.
    ///
    /// # Specification
    /// ```text
    /// The content of this processing instruction. This is from the first non white space
    /// character after the target to the character immediately preceding the ?>.
    ///
    /// Exceptions on setting
    ///     DOMException
    ///     NO_MODIFICATION_ALLOWED_ERR: Raised when the node is readonly.
    /// ```
    pub fn set_data(&mut self, value: impl Into<Rc<str>>) -> Result<(), DOMException> {
        check_no_modification_allowed_err(self)?;

        self.0.borrow_mut().data = Some(value.into());
        Ok(())
    }
}

impl Node for ProcessingInstructionRef {
    fn node_name(&self) -> Rc<str> {
        self.0.borrow().target.clone()
    }

    fn node_value(&self) -> Option<Rc<str>> {
        self.0.borrow().data.clone()
    }

    fn set_node_value(&mut self, value: impl Into<String>) -> Result<(), DOMException> {
        self.set_data(value.into())?;
        Ok(())
    }

    fn node_type(&self) -> NodeType {
        NodeType::ProcessingInstruction
    }

    fn parent_node(&self) -> Option<NodeRef> {
        self.0
            .borrow()
            .parent_node
            .as_ref()
            .and_then(|par| par.upgrade())
    }

    fn previous_sibling(&self) -> Option<NodeRef> {
        self.0
            .borrow()
            .previous_sibling
            .as_ref()
            .and_then(|prev| prev.upgrade())
    }

    fn next_sibling(&self) -> Option<NodeRef> {
        self.0.borrow().next_sibling.clone().map(From::from)
    }

    fn owner_document(&self) -> Option<DocumentRef> {
        self.0.borrow().owner_document.upgrade().map(From::from)
    }

    fn clone_node(&self, _deep: bool) -> NodeRef {
        let pi = ProcessingInstructionRef(
            Rc::new(RefCell::new(ProcessingInstruction {
                parent_node: None,
                previous_sibling: None,
                next_sibling: None,
                owner_document: self.0.borrow().owner_document.clone(),
                target: self.0.borrow().target.clone(),
                data: self.0.borrow().data.clone(),
                user_data: None,
                flag: 0,
            })),
            self.1.clone(),
        );

        self.handle_user_data(OperationType::NodeCloned, Some(pi.clone().into()));
        pi.into()
    }

    fn text_content(&self) -> Option<String> {
        self.node_value().map(|value| value.to_string())
    }

    fn set_text_content(&mut self, text: impl Into<String>) -> Result<(), super::DOMException> {
        let text: String = text.into();
        self.0.borrow_mut().data = Some(text.into());
        Ok(())
    }

    fn is_same_node(&self, other: &NodeRef) -> bool {
        let NodeRef::ProcessingInstruction(other) = other else {
            return false;
        };
        Rc::ptr_eq(&self.0, &other.0)
    }

    fn set_user_data(
        &mut self,
        key: impl Into<String>,
        data: DOMUserData,
        handler: Option<Arc<dyn UserDataHandler>>,
    ) -> Option<DOMUserData> {
        self.0
            .borrow_mut()
            .user_data
            .get_or_insert_default()
            .insert(key.into(), (data, handler))
            .map(|v| v.0)
    }

    fn get_user_data(&self, key: &str) -> Option<DOMUserData> {
        self.0
            .borrow()
            .user_data
            .as_ref()
            .and_then(|user_data| user_data.get(key))
            .map(|v| v.0.clone())
    }

    fn is_read_only(&self) -> bool {
        self.0.borrow().flag & 1 != 0
    }
}

impl NodeConnection for ProcessingInstructionRef {
    fn set_parent_node(&mut self, new_parent: Option<NodeRef>) -> Option<NodeRef> {
        replace(
            &mut self.0.borrow_mut().parent_node,
            new_parent.map(|par| par.downgrade()),
        )
        .and_then(|old| old.upgrade())
    }

    fn set_first_child(&mut self, _: Option<NodeRef>) -> Option<NodeRef> {
        None
    }

    fn set_last_child(&mut self, _: Option<NodeRef>) -> Option<NodeRef> {
        None
    }

    fn set_previous_sibling(&mut self, new_sibling: Option<NodeRef>) -> Option<NodeRef> {
        replace(
            &mut self.0.borrow_mut().previous_sibling,
            new_sibling.map(|sib| sib.downgrade()),
        )
        .and_then(|old| old.upgrade())
    }

    fn set_next_sibling(&mut self, new_sibling: Option<NodeRef>) -> Option<NodeRef> {
        replace(
            &mut self.0.borrow_mut().next_sibling,
            new_sibling.map(From::from),
        )
        .map(From::from)
    }

    fn set_owner_document(&mut self, new_doc: DocumentRef) -> Option<DocumentRef> {
        self.0.borrow_mut().owner_document = Rc::downgrade(&new_doc.0);
        Some(replace(&mut self.1, new_doc))
    }

    fn set_read_only(&mut self) {
        self.0.borrow_mut().flag |= 0b01;
    }

    fn unset_read_only(&mut self) {
        self.0.borrow_mut().flag &= !0b01;
    }

    fn adopted_to(&mut self, new_doc: DocumentRef) {
        self.0.borrow_mut().owner_document = Rc::downgrade(&new_doc.0);

        if let Some(user_data) = self.0.borrow().user_data.as_ref() {
            for (key, value) in user_data.iter() {
                if let Some(handler) = value.1.clone() {
                    handler.handle(
                        OperationType::NodeAdopted,
                        key.as_str(),
                        value.0.clone(),
                        self.clone().into(),
                        None,
                    );
                }
            }
        }
    }

    fn handle_user_data(&self, operation: OperationType, dst: Option<NodeRef>) {
        if let Some(user_data) = self.0.borrow().user_data.as_ref() {
            for (key, value) in user_data.iter() {
                if let Some(handler) = value.1.clone() {
                    handler.handle(
                        operation,
                        key.as_str(),
                        value.0.clone(),
                        self.clone().into(),
                        dst.clone(),
                    );
                }
            }
        }
    }
}

impl From<ProcessingInstructionRef> for NodeRef {
    fn from(value: ProcessingInstructionRef) -> Self {
        NodeRef::ProcessingInstruction(value)
    }
}

impl From<Rc<RefCell<ProcessingInstruction>>> for ProcessingInstructionRef {
    fn from(value: Rc<RefCell<ProcessingInstruction>>) -> Self {
        let doc = value.borrow().owner_document().unwrap();
        Self(value, doc)
    }
}