use nom::{
    IResult,
    branch::alt,
    bytes::complete::tag,
    combinator::{into, opt, map_res},
    multi::separated_list1,
    sequence::tuple,
};

use crate::model::{GroupRef, AddressRef, MailboxRef};
use crate::mailbox::{addr_spec, mailbox};
use crate::misc_token::phrase;
use crate::whitespace::{cfws};

/// Address (section 3.4 of RFC5322)
///
/// ```abnf
///    address         =   mailbox / group
/// ```
pub fn address(input: &str) -> IResult<&str, AddressRef> {
    alt((into(mailbox), into(group)))(input)
}

/// Group
///
/// ```abnf
///    group           =   display-name ":" [group-list] ";" [CFWS]
///    display-name    =   phrase
/// ```
pub fn group(input: &str) -> IResult<&str, GroupRef> {
    let (input, (grp_name, _, grp_list, _, _)) = 
        tuple((phrase, tag(":"), group_list, tag(";"), opt(cfws)))(input)?;

    Ok((input, GroupRef {
        name: grp_name,
        participants: grp_list,
    }))
}

/// Group list
///
/// ```abnf
///    group-list      =   mailbox-list / CFWS / obs-group-list
/// ```
pub fn group_list(input: &str) -> IResult<&str, Vec<MailboxRef>> {
    alt((mailbox_list, mx_cfws))(input)
}

fn mx_cfws(input: &str) -> IResult<&str, Vec<MailboxRef>> {
    let (input, _) = cfws(input)?;
    Ok((input, vec![]))
}

/// Mailbox list
///
/// ```abnf
///    mailbox-list    =   (mailbox *("," mailbox)) / obs-mbox-list
/// ```
pub fn mailbox_list(input: &str) -> IResult<&str, Vec<MailboxRef>> {
    separated_list1(tag(","), mailbox)(input)
}

/// Address list
///
/// ```abnf
///   address-list    =   (address *("," address)) / obs-addr-list
/// ```
pub fn address_list(input: &str) -> IResult<&str, Vec<AddressRef>> {
    separated_list1(tag(","), address)(input)
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::model::AddrSpec;

    #[test]
    fn test_mailbox_list() {
        match mailbox_list(r#"Pete(A nice \) chap) <pete(his account)@silly.test(his host)>"#) {
            Ok(("", _)) => (),
            _ => panic!(),
        };

        match mailbox_list(r#"Mary Smith <mary@x.test>, jdoe@example.org, Who? <one@y.test>, <boss@nil.test>, "Giant; \"Big\" Box" <sysservices@example.net>"#) {
            Ok(("", _)) => (),
            _ => panic!(),
        };
    }

    #[test]
    fn test_address_list() {
        assert_eq!(
            address_list(r#"A Group:Ed Jones <c@a.test>,joe@where.test,John <jdoe@one.test>;, Mary Smith <mary@x.test>"#),
            Ok(("", vec![
                AddressRef::Many(GroupRef { 
                    name: "A Group".to_string(), 
                    participants: vec![
                        MailboxRef {
                            name: Some("Ed Jones".into()),
                            addrspec: AddrSpec { local_part: "c".into(), domain: "a.test".into() },
                        },
                        MailboxRef {
                            name: None,
                            addrspec: AddrSpec { local_part: "joe".into(), domain: "where.test".into() },
                        },
                        MailboxRef {
                            name: Some("John".into()),
                            addrspec: AddrSpec { local_part: "jdoe".into(), domain: "one.test".into() },
                        },
                    ],
                }),
                AddressRef::Single(MailboxRef { 
                    name: Some("Mary Smith".into()),
                    addrspec: AddrSpec { local_part: "mary".into(), domain: "x.test".into() },
                }),
            ]))
        );
    }
}