#| The kind of host found in the URI (a domain name or some kind of IP address)
enum Cro::ResourceIdentifier::Host <RegName IPv4 IPv6 IPvFuture>;

package Cro::ResourceIdentifier {
    #| Perform percent sequence decoding according to the URI specification.
    #| Anything outside of the ASCII range will be interpreted as UTF-8.
    our sub decode-percents(Str $s) is export(:decode-percents) {
        $s.contains('%')
                ?? $s.subst(:g, /['%' (<[A..Fa..f0..9]> ** 2)]+/,
                        -> $perseq {
                            Blob.new($perseq[0].map({ :16(.Str) })).decode('utf8')
                        })
                !! $s
    }

    #| Perform percent sequence encoding according to the URI specification.
    #| Any characters outside of the ASCII range will be encoded as UTF-8,
    #| and then each octet represented as a percent escape.
    our sub encode-percents(Str $s) is export(:encode-percents) {
        $s.subst: :g, /<-[A..Za..z0..9_.~-]>+/, {
            .Str.encode('utf8').list.map({ $_ > 16 ?? "%" ~ .base(16) !! "%0" ~ .base(16) }).join
        }
    }

    our sub encode-percents-except-ASCII(Str $s) is export(:encode-percents) {
        $s.subst: :g, /<-[A..Za..z0..9_.~:/%=-]>+/, {
            .Str.encode('utf8').list.map({ $_ > 16 ?? "%" ~ .base(16) !! "%0" ~ .base(16) }).join
        }
    }
}

role Cro::ResourceIdentifier {
    #| Given the example "https://[email protected]:44433/example/url?foo=bar&x=42#here",
    #| this would return "https"
    has Str $.scheme;

    #| Given the example "https://[email protected]:44433/example/url?foo=bar&x=42#here",
    #| this would return "[email protected]:44433"
    has Str $.authority;

    #| Given the example "https://[email protected]:44433/example/url?foo=bar&x=42#here",
    #| this would return "user"
    has Str $.userinfo;

    #| Given the example "https://[email protected]:44433/example/url?foo=bar&x=42#here",
    #| this would return "cro.services"
    has Str $.host;

    #| Given the example "https://[email protected]:44433/example/url?foo=bar&x=42#here",
    #| this would return Cro::Uri::Host::RegName
    has Cro::ResourceIdentifier::Host $.host-class;

    #| Given the example "https://[email protected]:44433/example/url?foo=bar&x=42#here",
    #| this would return 44433
    has $.port;

    #| Given the example "https://[email protected]:44433/example/url?foo=bar&x=42#here",
    #| this would return "/example/url"
    has Str $.path;

    #| Given the example "https://[email protected]:44433/example/url?foo=bar&x=42#here",
    #| this would return "foo=bar&x=42"
    has Str $.query;

    #| Given the example "https://[email protected]:44433/example/url?foo=bar&x=42#here",
    #| this would return "here"
    has Str $.fragment;

    #| Return an array of path segments, decoding any percent sequences found in
    #| them. Given the example "https://[email protected]:44433/example/url?foo=bar&x=42#here",
    #| this would return an array ["example", "foo"].
    method path-segments(Cro::ResourceIdentifier:D: --> List) {
        my $no-leader = $!path.starts-with('/') ?? $!path.substr(1) !! $!path;
        $no-leader.split('/').map(&Cro::ResourceIdentifier::decode-percents).list
    }
}