use std::borrow::Cow;
use crate::name_analysis::symbol::Symbol;
use std::range::Range;
use crate::ast::node::named::Named;

#[derive(Debug)]
pub struct Identifier {
    name: String,
    file_id: usize,
    range: Range<usize>,
    scope_id: Option<usize>,
    saved_symbol: Option<Symbol>,
}

impl Identifier {
    pub fn new(name: &str, file_id: usize, range: Range<usize>) -> Self {
        Self {
            name: name.to_string(),
            file_id,
            range,
            scope_id: None,
            saved_symbol: None,
        }
    }
}

impl Named for Identifier {
    fn name(&self) -> Cow<'_, str> {
        Cow::Borrowed(&self.name)
    }

    fn file_id(&self) -> usize {
        self.file_id
    }

    fn range(&self) -> Range<usize> {
        self.range
    }

    fn set_scope_id(&mut self, id: usize) {
        self.scope_id = Some(id);
    }

    fn scope_id(&self) -> Option<usize> {
        self.scope_id
    }

    fn set_saved_symbol(&mut self, saved_symbol: Symbol) {
        self.saved_symbol = Some(saved_symbol);
    }

    fn saved_symbol(&self) -> Option<Symbol> {
        self.saved_symbol.clone()
    }
}

#[derive(Debug)]
pub struct FullyQualifiedName {
    identifiers: Vec<Box<Identifier>>,
    file_id: usize,
    range: Range<usize>,
    scope_id: Option<usize>,
    saved_symbol: Option<Symbol>,
}

impl FullyQualifiedName {
    pub fn new(identifiers: Vec<Box<Identifier>>, file_id: usize, range: Range<usize>) -> Self {
        Self {
            identifiers,
            range,
            file_id,
            scope_id: None,
            saved_symbol: None,
        }
    }

    pub fn identifiers(&self) -> Vec<&Identifier> {
        self.identifiers.iter().map(Box::as_ref).collect()
    }

    pub fn identifiers_mut(&mut self) -> Vec<&mut Identifier> {
        self.identifiers.iter_mut().map(Box::as_mut).collect()
    }

    #[deprecated(note = "Grammar will instead distinguish between fqns and identifiers")]
    pub fn last(&self) -> &Identifier {
        &self.identifiers[self.identifiers.len() - 1]
    }

    #[deprecated(note = "Grammar will instead distinguish between fqns and identifiers")]
    pub fn last_mut(&mut self) -> &mut Identifier {
        let last_index = self.identifiers.len() - 1;
        &mut self.identifiers[last_index]
    }

    #[deprecated(note = "Grammar will instead distinguish between fqns and identifiers")]
    pub fn len(&self) -> usize {
        self.identifiers.len()
    }

    #[deprecated(note = "Grammar will instead distinguish between fqns and identifiers")]
    pub fn is_single_identifier(&self) -> bool {
        self.identifiers.len() == 1
    }
}

impl Named for FullyQualifiedName {
    fn name(&self) -> Cow<'_, str> {
        if self.identifiers.len() == 1 {
            self.identifiers[0].name()
        } else {
            let mut acc = String::new();
            for (i, identifier) in self.identifiers.iter().enumerate() {
                acc += &identifier.name();
                if i < self.identifiers.len() - 1 {
                    acc += "::";
                }
            }
            Cow::Owned(acc)
        }
    }

    fn file_id(&self) -> usize {
        self.file_id
    }

    fn range(&self) -> Range<usize> {
        self.range
    }

    fn set_scope_id(&mut self, id: usize) {
        self.scope_id = Some(id);
    }

    fn scope_id(&self) -> Option<usize> {
        self.scope_id
    }

    fn set_saved_symbol(&mut self, symbol: Symbol) {
        self.saved_symbol = Some(symbol);
    }

    fn saved_symbol(&self) -> Option<Symbol> {
        self.saved_symbol.clone()
    }
}