extern crate minidom;

use hashes::{Hash, parse_hash};

use minidom::Element;

use error::Error;
use ns;

#[derive(Debug, Clone, PartialEq)]
pub struct Range {
    pub offset: u64,
    pub length: Option<u64>,
    pub hashes: Vec<Hash>,
}

#[derive(Debug, Clone)]
pub struct File {
    pub date: Option<String>,
    pub media_type: Option<String>,
    pub name: Option<String>,
    pub size: Option<String>,
    pub range: Option<Range>,
    pub hashes: Vec<Hash>,
}

#[derive(Debug, Clone)]
pub struct Description {
    pub file: File,
}

#[derive(Debug, Clone)]
pub struct Creator {
    pub creator: String,
}

#[derive(Debug, Clone)]
pub struct Checksum {
    pub name: String,
    pub creator: Creator,
    pub file: File,
}

pub fn parse_jingle_ft(root: &Element) -> Result<Description, Error> {
    if !root.is("description", ns::JINGLE_FT) {
        return Err(Error::ParseError("This is not a JingleFT description element."));
    }
    if root.children().collect::<Vec<_>>().len() != 1 {
        return Err(Error::ParseError("JingleFT description element must have exactly one child."));
    }

    let mut date = None;
    let mut media_type = None;
    let mut name = None;
    let mut size = None;
    let mut range = None;
    let mut hashes = vec!();
    for description_payload in root.children() {
        if !description_payload.is("file", ns::JINGLE_FT) {
            return Err(Error::ParseError("Unknown element in JingleFT description."));
        }
        for file_payload in description_payload.children() {
            if file_payload.is("date", ns::JINGLE_FT) {
                if date.is_some() {
                    return Err(Error::ParseError("File must not have more than one date."));
                }
                date = Some(file_payload.text());
            } else if file_payload.is("media-type", ns::JINGLE_FT) {
                if media_type.is_some() {
                    return Err(Error::ParseError("File must not have more than one media-type."));
                }
                media_type = Some(file_payload.text());
            } else if file_payload.is("name", ns::JINGLE_FT) {
                if name.is_some() {
                    return Err(Error::ParseError("File must not have more than one name."));
                }
                name = Some(file_payload.text());
            } else if file_payload.is("size", ns::JINGLE_FT) {
                if size.is_some() {
                    return Err(Error::ParseError("File must not have more than one size."));
                }
                size = Some(file_payload.text());
            } else if file_payload.is("range", ns::JINGLE_FT) {
                if range.is_some() {
                    return Err(Error::ParseError("File must not have more than one range."));
                }
                let offset = file_payload.attr("offset").unwrap_or("0").parse()?;
                let length = match file_payload.attr("length") {
                    Some(length) => Some(length.parse()?),
                    None => None,
                };
                let mut range_hashes = vec!();
                for hash_element in file_payload.children() {
                    if !hash_element.is("hash", ns::HASHES) {
                        return Err(Error::ParseError("Unknown element in JingleFT range."));
                    }
                    range_hashes.push(parse_hash(hash_element)?);
                }
                range = Some(Range {
                    offset: offset,
                    length: length,
                    hashes: range_hashes,
                });
            } else if file_payload.is("hash", ns::HASHES) {
                hashes.push(parse_hash(file_payload)?);
            } else {
                return Err(Error::ParseError("Unknown element in JingleFT file."));
            }
        }
    }

    Ok(Description {
        file: File {
            date: date,
            media_type: media_type,
            name: name,
            size: size,
            range: range,
            hashes: hashes,
        },
    })
}

#[cfg(test)]
mod tests {
    use minidom::Element;
    use jingle_ft;

    #[test]
    fn test_description() {
        let elem: Element = r#"
<description xmlns='urn:xmpp:jingle:apps:file-transfer:5'>
  <file>
    <media-type>text/plain</media-type>
    <name>test.txt</name>
    <date>2015-07-26T21:46:00</date>
    <size>6144</size>
    <hash xmlns='urn:xmpp:hashes:2'
          algo='sha-1'>w0mcJylzCn+AfvuGdqkty2+KP48=</hash>
  </file>
</description>
"#.parse().unwrap();

        let desc = jingle_ft::parse_jingle_ft(&elem).unwrap();
        assert_eq!(desc.file.media_type, Some(String::from("text/plain")));
        assert_eq!(desc.file.name, Some(String::from("test.txt")));
        assert_eq!(desc.file.date, Some(String::from("2015-07-26T21:46:00")));
        assert_eq!(desc.file.size, Some(String::from("6144")));
        assert_eq!(desc.file.range, None);
        assert_eq!(desc.file.hashes[0].algo, "sha-1");
        assert_eq!(desc.file.hashes[0].hash, "w0mcJylzCn+AfvuGdqkty2+KP48=");
    }

    #[test]
    fn test_request() {
        let elem: Element = r#"
<description xmlns='urn:xmpp:jingle:apps:file-transfer:5'>
  <file>
    <hash xmlns='urn:xmpp:hashes:2'
          algo='sha-1'>w0mcJylzCn+AfvuGdqkty2+KP48=</hash>
  </file>
</description>
"#.parse().unwrap();

        let desc = jingle_ft::parse_jingle_ft(&elem).unwrap();
        assert_eq!(desc.file.media_type, None);
        assert_eq!(desc.file.name, None);
        assert_eq!(desc.file.date, None);
        assert_eq!(desc.file.size, None);
        assert_eq!(desc.file.range, None);
        assert_eq!(desc.file.hashes[0].algo, "sha-1");
        assert_eq!(desc.file.hashes[0].hash, "w0mcJylzCn+AfvuGdqkty2+KP48=");
    }
}