use quick_xml::events::Event;
use quick_xml::name::ResolveResult;

use crate::prelude::*;
use crate::util::xml::*;

use super::bind::Jid;

pub const XMLNS_INFO: &'static str = "http://jabber.org/protocol/disco#info";
pub const XMLNS_ITEM: &'static str = "http://jabber.org/protocol/disco#item";

#[derive(PartialEq, Eq, Debug)]
pub struct InfoQuery {
    pub node: Option<String>,
    pub identity: Vec<Identity>,
    pub feature: Vec<Feature>,
}

impl FromXml for InfoQuery {
    type P = impl Parser<Output = Result<Self>>;

    fn parse() -> Self::P {
        |(namespace, event): (ResolveResult<'static>, &'static Event<'static>)| -> Result<Self> {
            let mut node = None;
            let mut identity = vec![];
            let mut feature = vec![];
            let (bytes, end) = match event {
                Event::Start(bytes) => (bytes, false),
                Event::Empty(bytes) => (bytes, true),
                _ => return Err(ffail!("Unexpected XML event: {event:?}")),
            };
            for attr in bytes.attributes() {
                let attr = attr?;
                match attr.key.0 {
                    b"node" => {
                        let s = std::str::from_utf8(bytes)?;
                        node = Some(s.to_owned())
                    }
                    _ => {}
                }
            }
            if end {
                return Ok(InfoQuery {
                    node,
                    identity,
                    feature,
                });
            }
            loop {
                let (namespace, event) = yield;
                let bytes = match event {
                    Event::Start(bytes) => bytes,
                    Event::Empty(bytes) => bytes,
                    Event::End(_) => break,
                    _ => return Err(ffail!("Unexpected XML event: {event:?}")),
                };
                if bytes.name().0 == Identity::NAME.as_bytes() {
                    let res = delegate_parsing!(Identity, namespace, event)?;
                    identity.push(res);
                } else if bytes.name().0 == Feature::NAME.as_bytes() {
                    let res = delegate_parsing!(Feature, namespace, event)?;
                    feature.push(res);
                } else {
                    return Err(ffail!("Unexpected XML event: {event:?}"));
                }
            }
            return Ok(InfoQuery {
                node,
                identity,
                feature,
            });
        }
    }
}

impl FromXmlTag for InfoQuery {
    const NAME: &'static str = "query";

    const NS: &'static str = XMLNS_INFO;
}

#[derive(PartialEq, Eq, Debug)]
pub struct Identity {
    category: String,
    name: Option<String>,
    r#type: String,
}

impl FromXml for Identity {
    type P = impl Parser<Output = Result<Self>>;

    fn parse() -> Self::P {
        |(namespace, event): (ResolveResult<'static>, &'static Event<'static>)| -> Result<Self> {
            let mut category = None;
            let mut name = None;
            let mut r#type = None;
            let (bytes, end) = match event {
                Event::Start(bytes) => (bytes, false),
                Event::Empty(bytes) => (bytes, true),
                _ => return Err(ffail!("Unexpected XML event: {event:?}")),
            };
            for attr in bytes.attributes() {
                let attr = attr?;
                match attr.key.0 {
                    b"category" => {
                        let s = std::str::from_utf8(bytes)?;
                        category = Some(s.to_owned())
                    }
                    b"name" => {
                        let s = std::str::from_utf8(bytes)?;
                        name = Some(s.to_owned())
                    }
                    b"type" => {
                        let s = std::str::from_utf8(bytes)?;
                        r#type = Some(s.to_owned())
                    }
                    _ => {}
                }
            }
            let Some(category) = category else {
                return Err(ffail!("No jid provided"));
            };
            let Some(r#type) = r#type else {
                return Err(ffail!("No type provided"));
            };
            let item = Identity {
                category,
                name,
                r#type,
            };
            if end {
                return Ok(item);
            }

            let (namespace, event) = yield;
            let Event::End(bytes) = event else {
                return Err(ffail!("Unexpected XML event: {event:?}"));
            };
            Ok(item)
        }
    }
}

impl FromXmlTag for Identity {
    const NAME: &'static str = "identity";

    const NS: &'static str = XMLNS_INFO;
}

#[derive(PartialEq, Eq, Debug)]
pub struct Feature {
    pub var: String,
}

impl FromXml for Feature {
    type P = impl Parser<Output = Result<Self>>;

    fn parse() -> Self::P {
        |(namespace, event): (ResolveResult<'static>, &'static Event<'static>)| -> Result<Self> {
            let mut var = None;
            let (bytes, end) = match event {
                Event::Start(bytes) => (bytes, false),
                Event::Empty(bytes) => (bytes, true),
                _ => return Err(ffail!("Unexpected XML event: {event:?}")),
            };
            for attr in bytes.attributes() {
                let attr = attr?;
                match attr.key.0 {
                    b"var" => {
                        let s = std::str::from_utf8(bytes)?;
                        var = Some(s.to_owned())
                    }
                    _ => {}
                }
            }
            let Some(var) = var else {
                return Err(ffail!("No jid provided"));
            };
            let item = Feature { var };
            if end {
                return Ok(item);
            }

            let (namespace, event) = yield;
            let Event::End(bytes) = event else {
                return Err(ffail!("Unexpected XML event: {event:?}"));
            };
            Ok(item)
        }
    }
}

impl FromXmlTag for Feature {
    const NAME: &'static str = "feature";

    const NS: &'static str = XMLNS_INFO;
}

#[derive(PartialEq, Eq, Debug)]
pub struct ItemQuery {
    pub item: Vec<Item>,
}

impl FromXml for ItemQuery {
    type P = impl Parser<Output = Result<Self>>;

    fn parse() -> Self::P {
        |(namespace, event): (ResolveResult<'static>, &'static Event<'static>)| -> Result<Self> {
            let mut item = vec![];
            let (bytes, end) = match event {
                Event::Start(bytes) => (bytes, false),
                Event::Empty(bytes) => (bytes, true),
                _ => return Err(ffail!("Unexpected XML event: {event:?}")),
            };
            if end {
                return Ok(ItemQuery { item });
            }
            loop {
                let (namespace, event) = yield;
                let bytes = match event {
                    Event::Start(bytes) => bytes,
                    Event::Empty(bytes) => bytes,
                    Event::End(_) => break,
                    _ => return Err(ffail!("Unexpected XML event: {event:?}")),
                };
                if bytes.name().0 == Item::NAME.as_bytes() {
                    let res = delegate_parsing!(Item, namespace, event)?;
                    item.push(res);
                } else {
                    return Err(ffail!("Unexpected XML event: {event:?}"));
                }
            }
            Ok(ItemQuery { item })
        }
    }
}

impl FromXmlTag for ItemQuery {
    const NAME: &'static str = "query";

    const NS: &'static str = XMLNS_ITEM;
}

#[derive(PartialEq, Eq, Debug)]
pub struct Item {
    pub jid: super::bind::Jid,
    pub name: Option<String>,
    pub node: Option<String>,
}

impl FromXml for Item {
    type P = impl Parser<Output = Result<Self>>;

    fn parse() -> Self::P {
        |(namespace, event): (ResolveResult<'static>, &'static Event<'static>)| -> Result<Self> {
            let mut jid = None;
            let mut name = None;
            let mut node = None;
            let (bytes, end) = match event {
                Event::Start(bytes) => (bytes, false),
                Event::Empty(bytes) => (bytes, true),
                _ => return Err(ffail!("Unexpected XML event: {event:?}")),
            };
            for attr in bytes.attributes() {
                let attr = attr?;
                match attr.key.0 {
                    b"name" => {
                        let s = std::str::from_utf8(bytes)?;
                        name = Some(s.to_owned())
                    }
                    b"node" => {
                        let s = std::str::from_utf8(bytes)?;
                        node = Some(s.to_owned())
                    }
                    b"jid" => {
                        let s = std::str::from_utf8(bytes)?;
                        let s = Jid::from_string(s)?;
                        jid = Some(s)
                    }
                    _ => {}
                }
            }
            let Some(jid) = jid else {
                return Err(ffail!("No jid provided"));
            };
            let item = Item { jid, name, node };
            if end {
                return Ok(item);
            }

            let (namespace, event) = yield;
            let Event::End(bytes) = event else {
                return Err(ffail!("Unexpected XML event: {event:?}"));
            };
            Ok(item)
        }
    }
}

impl FromXmlTag for Item {
    const NAME: &'static str = "item";

    const NS: &'static str = XMLNS_ITEM;
}