// Copyright 2014-2017 The html5ever Project Developers. See the
// COPYRIGHT file at the top-level directory of this distribution.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

use crate::error::Error;
use crate::tokenizer::states;
#[cfg(feature = "spans")]
use std::ops::Range;

pub use self::TagKind::{EndTag, StartTag};
pub use self::Token::{CharacterTokens, CommentToken, DoctypeToken, TagToken};
pub use self::Token::{EOFToken, NullCharacterToken, ParseError};

/// A `DOCTYPE` token.
// FIXME: already exists in Servo DOM
#[derive(PartialEq, Eq, Clone, Debug)]
pub struct Doctype {
    pub name: Option<String>,
    pub public_id: Option<String>,
    pub system_id: Option<String>,
    pub force_quirks: bool,
}

impl Doctype {
    pub fn new() -> Doctype {
        Doctype {
            name: None,
            public_id: None,
            system_id: None,
            force_quirks: false,
        }
    }
}

#[derive(PartialEq, Eq, Hash, Copy, Clone, Debug)]
pub enum TagKind {
    StartTag,
    EndTag,
}

/// A tag attribute, e.g. `class="test"` in `<div class="test" ...>`.
///
/// The namespace on the attribute name is almost always ns!("").
/// The tokenizer creates all attributes this way, but the tree
/// builder will adjust certain attribute names inside foreign
/// content (MathML, SVG).
#[derive(PartialEq, Eq, Clone, Debug)]
pub struct Attribute {
    /// The name of the attribute (e.g. the `class` in `<div class="test">`)
    pub name: String,
    /// The value of the attribute (e.g. the `"test"` in `<div class="test">`)
    pub value: String,
    #[cfg(feature = "spans")]
    #[cfg_attr(docsrs, doc(cfg(feature = "spans")))]
    pub name_span: Range<usize>,
    #[cfg(feature = "spans")]
    #[cfg_attr(docsrs, doc(cfg(feature = "spans")))]
    pub value_span: Range<usize>,
}

impl Ord for Attribute {
    fn cmp(&self, other: &Self) -> std::cmp::Ordering {
        (&self.name, &self.value).cmp(&(&other.name, &other.value))
    }
}

impl PartialOrd for Attribute {
    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
        (&self.name, &self.value).partial_cmp(&(&other.name, &other.value))
    }
}

/// A tag token.
#[derive(PartialEq, Eq, Clone, Debug)]
pub struct Tag {
    pub kind: TagKind,
    pub name: String,
    pub self_closing: bool,
    pub attrs: Vec<Attribute>,
    #[cfg(feature = "spans")]
    #[cfg_attr(docsrs, doc(cfg(feature = "spans")))]
    pub name_span: Range<usize>,
}

impl Tag {
    /// Are the tags equivalent when we don't care about attribute order?
    /// Also ignores the self-closing flag and spans.
    pub fn equiv_modulo_attr_order(&self, other: &Tag) -> bool {
        if (self.kind != other.kind) || (self.name != other.name) {
            return false;
        }

        let mut self_attrs = self.attrs.clone();
        let mut other_attrs = other.attrs.clone();
        self_attrs.sort();
        other_attrs.sort();

        self_attrs == other_attrs
    }
}

#[derive(PartialEq, Eq, Debug)]
pub enum Token {
    DoctypeToken(Doctype),
    TagToken(Tag),
    CommentToken(String),
    CharacterTokens(String),
    NullCharacterToken,
    EOFToken,
    ParseError {
        error: Error,
        #[cfg(feature = "spans")]
        #[cfg_attr(docsrs, doc(cfg(feature = "spans")))]
        span: std::ops::Range<usize>,
    },
}

#[derive(Debug, PartialEq)]
#[must_use]
pub enum TokenSinkResult {
    Continue,
    Break,
    Plaintext,
    RawData(states::RawKind),
}

/// Types which can receive tokens from the tokenizer.
pub trait TokenSink {
    /// Process a token.
    fn process_token(&mut self, token: Token, line_number: u64) -> TokenSinkResult;

    // Signal sink that tokenization reached the end.
    fn end(&mut self) {}

    /// Used in the markup declaration open state. By default, this always
    /// returns false and thus all CDATA sections are tokenized as bogus
    /// comments.
    /// <https://html.spec.whatwg.org/multipage/#markup-declaration-open-state>
    fn adjusted_current_node_present_but_not_in_html_namespace(&self) -> bool {
        false
    }
}