namespace PlotLine.Services;

public static class CharacterSexHintService
{
    public const string Unknown = "Unknown";
    public const string Female = "Female";
    public const string Male = "Male";
    public const string NonBinaryOrOther = "NonBinaryOrOther";

    private static readonly HashSet<string> FemaleNames = new(StringComparer.OrdinalIgnoreCase)
    {
        "abby", "abigail", "alice", "alison", "allison", "amanda", "amelia", "amy", "angela", "anna", "anne",
        "beth", "bethany", "carol", "caroline", "catherine", "charlotte", "chloe", "cindy", "claire", "daisy",
        "diana", "emily", "emma", "eva", "eve", "grace", "hannah", "helen", "isabel", "isabella", "jane",
        "jessica", "julia", "julie", "kate", "katie", "laura", "lily", "lucy", "maggie", "margaret", "mary",
        "molly", "nicola", "olivia", "rachel", "rebecca", "rose", "sarah", "sophie", "susan", "victoria",
        "zoe"
    };

    private static readonly HashSet<string> MaleNames = new(StringComparer.OrdinalIgnoreCase)
    {
        "adam", "alan", "alexander", "andrew", "anthony", "arthur", "ben", "benjamin", "brian", "charles",
        "chris", "christopher", "daniel", "david", "edward", "george", "harry", "henry", "ian", "jack",
        "james", "john", "jonathan", "joseph", "kevin", "mark", "matthew", "michael", "nick", "nicolas",
        "nicholas", "oliver", "paul", "peter", "philip", "richard", "robert", "samuel", "simon", "stephen",
        "steven", "thomas", "tom", "william"
    };

    private static readonly HashSet<string> AmbiguousNames = new(StringComparer.OrdinalIgnoreCase)
    {
        "alex", "andy", "ashley", "billie", "blair", "bobbie", "casey", "charlie", "drew", "frankie",
        "jamie", "jessie", "jo", "jordan", "lee", "leslie", "morgan", "pat", "riley", "robyn", "robin",
        "sam", "sandy", "shannon", "taylor", "terry"
    };

    public static string Suggest(string? name)
    {
        var token = FirstNameToken(name);
        if (string.IsNullOrWhiteSpace(token) || AmbiguousNames.Contains(token))
        {
            return Unknown;
        }

        if (FemaleNames.Contains(token))
        {
            return Female;
        }

        return MaleNames.Contains(token) ? Male : Unknown;
    }

    public static string Normalise(string? value, string? fallbackName = null)
        => value?.Trim() switch
        {
            Female => Female,
            Male => Male,
            NonBinaryOrOther => NonBinaryOrOther,
            Unknown => Unknown,
            _ => Suggest(fallbackName)
        };

    private static string FirstNameToken(string? name)
    {
        var clean = name?.Trim();
        if (string.IsNullOrWhiteSpace(clean))
        {
            return string.Empty;
        }

        var first = clean.Split(' ', StringSplitOptions.RemoveEmptyEntries).FirstOrDefault() ?? string.Empty;
        return first.Trim('.', ',', ';', ':', '\'', '"').ToLowerInvariant();
    }
}