use std::collections::VecDeque;
use std::ops::Range;

use crate::offset::Offset;
use crate::Emitter;
use crate::Error;
use crate::Token;

/// An [`Emitter`] implementation that yields [`Token`].
pub struct BasicEmitter<O> {
    errors: VecDeque<(Error, Range<O>)>,
}

impl<O: Default> Default for BasicEmitter<O> {
    fn default() -> Self {
        BasicEmitter {
            errors: VecDeque::new(),
        }
    }
}

impl<O> BasicEmitter<O> {
    /// Removes all encountered tokenizer errors and returns them as an iterator.
    pub fn drain_errors(&mut self) -> impl Iterator<Item = (Error, Range<O>)> + '_ {
        self.errors.drain(0..)
    }
}

impl<O> Iterator for BasicEmitter<O> {
    type Item = Token<O>;

    fn next(&mut self) -> Option<Self::Item> {
        todo!()
    }
}

#[allow(unused_variables)]
impl<O: Offset> Emitter<O> for BasicEmitter<O> {
    fn report_error(&mut self, error: Error, span: Range<O>) {
        todo!()
    }

    fn emit_char(&mut self, c: char) {
        todo!()
    }

    fn emit_eof(&mut self) {
        todo!()
    }

    fn init_start_tag(&mut self, tag_offset: O, name_offset: O) {
        todo!()
    }

    fn init_end_tag(&mut self, tag_offset: O, name_offset: O) {
        todo!()
    }

    fn push_tag_name(&mut self, s: &str) {
        todo!()
    }

    fn init_attribute_name(&mut self, offset: O) {
        todo!()
    }

    fn push_attribute_name(&mut self, s: &str) {
        todo!()
    }

    fn push_attribute_value(&mut self, s: &str) {
        todo!()
    }

    fn set_self_closing(&mut self, slash_span: Range<O>) {
        todo!()
    }

    fn emit_current_tag(&mut self, offset: O) {
        todo!()
    }

    fn init_comment(&mut self, data_start_offset: O) {
        todo!()
    }

    fn push_comment(&mut self, s: &str) {
        todo!()
    }

    fn emit_current_comment(&mut self, data_end_offset: O) {
        todo!()
    }

    fn init_doctype(&mut self, offset: O) {
        todo!()
    }

    fn push_doctype_name(&mut self, s: &str) {
        todo!()
    }

    fn init_doctype_public_id(&mut self, offset: O) {
        todo!()
    }

    fn push_doctype_public_id(&mut self, s: &str) {
        todo!()
    }

    fn init_doctype_system_id(&mut self, offset: O) {
        todo!()
    }

    fn push_doctype_system_id(&mut self, s: &str) {
        todo!()
    }

    fn set_force_quirks(&mut self) {
        todo!()
    }

    fn emit_current_doctype(&mut self, offset: O) {
        todo!()
    }
}