using System.Text.RegularExpressions;

namespace Parser.Core;

public static class LanguageParser
{
    private static readonly Regex LanguageRegex = new(@"(?:\W|_|^)(?<english>\beng\b)|
                                                        (?<italian>\b(?:ita|italian)\b)|
                                                        (?<german>(?:swiss)?german\b|videomann|ger[. ]dub|\bger\b)|
                                                        (?<flemish>flemish)|
                                                        (?<bulgarian>bgaudio)|
                                                        (?<romanian>rodubbed)|
                                                        (?<brazilian>\b(dublado|pt-BR)\b)|
                                                        (?<greek>greek)|
                                                        (?<french>\b(?:FR|VO|VF|VFF|VFQ|VFI|VF2|TRUEFRENCH|FRENCH|FRE|FRA)\b)|
                                                        (?<russian>\b(?:rus|ru)\b)|
                                                        (?<hungarian>\b(?:HUNDUB|HUN)\b)|
                                                        (?<hebrew>\b(?:HebDub|HebDubbed)\b)|
                                                        (?<polish>\b(?:PL\W?DUB|DUB\W?PL|LEK\W?PL|PL\W?LEK)\b)|
                                                        (?<chinese>\[(?:CH[ST]|BIG5|GB)\]|简|繁|字幕)|
                                                        (?<ukrainian>(?:(?:\dx)?UKR))|
                                                        (?<spanish>\b(?:español|castellano)\b)|
                                                        (?<catalan>\b(?:catalan?|catalán|català)\b)|
                                                        (?<latvian>\b(?:lat|lav|lv)\b)|
                                                        (?<telugu>\btel\b)|
                                                        (?<vietnamese>\bVIE\b)|
                                                        (?<japanese>\bJAP\b)|
                                                        (?<korean>\bKOR\b)|
                                                        (?<urdu>\burdu\b)|
                                                        (?<romansh>\b(?:romansh|rumantsch|romansch)\b)|
                                                        (?<mongolian>\b(?:mongolian|khalkha)\b)|
                                                        (?<georgian>\b(?:georgian|geo|ka|kat)\b)|
                                                        (?<original>\b(?:orig|original)\b)",
        RegexOptions.IgnoreCase | RegexOptions.Compiled | RegexOptions.IgnorePatternWhitespace);

    private static readonly Regex CaseSensitiveLanguageRegex = new(@"(?:(?i)(?<!SUB[\W|_|^]))(?:(?<english>\bEN\b)|
                                                                      (?<lithuanian>\bLT\b)|
                                                                      (?<czech>\bCZ\b)|
                                                                      (?<polish>\bPL\b)|
                                                                      (?<bulgarian>\bBG\b)|
                                                                      (?<slovak>\bSK\b)|
                                                                      (?<german>\bDE\b)|
                                                                      (?<spanish>\b(?<!DTS[._ -])ES\b))(?:(?i)(?![\W|_|^]SUB))",
        RegexOptions.Compiled | RegexOptions.IgnorePatternWhitespace);

    private static readonly Regex GermanDualLanguageRegex = new(@"(?<!WEB[-_. ]?)\bDL\b", RegexOptions.Compiled | RegexOptions.IgnoreCase);
    private static readonly Regex GermanMultiLanguageRegex = new(@"\bML\b", RegexOptions.Compiled | RegexOptions.IgnoreCase);

    public static List<Language> ParseLanguages(string title)
    {
        var lowerTitle = title.ToLower();
        var languages = new List<Language>();

        // Full word matches
        if (lowerTitle.Contains("english")) languages.Add(Language.English);
        if (lowerTitle.Contains("spanish")) languages.Add(Language.Spanish);
        if (lowerTitle.Contains("danish")) languages.Add(Language.Danish);
        if (lowerTitle.Contains("dutch")) languages.Add(Language.Dutch);
        if (lowerTitle.Contains("japanese")) languages.Add(Language.Japanese);
        if (lowerTitle.Contains("icelandic")) languages.Add(Language.Icelandic);
        if (lowerTitle.Contains("mandarin") || lowerTitle.Contains("cantonese") || lowerTitle.Contains("chinese")) languages.Add(Language.Chinese);
        if (lowerTitle.Contains("korean")) languages.Add(Language.Korean);
        if (lowerTitle.Contains("russian")) languages.Add(Language.Russian);
        if (lowerTitle.Contains("romanian")) languages.Add(Language.Romanian);
        if (lowerTitle.Contains("hindi")) languages.Add(Language.Hindi);
        if (lowerTitle.Contains("arabic")) languages.Add(Language.Arabic);
        if (lowerTitle.Contains("thai")) languages.Add(Language.Thai);
        if (lowerTitle.Contains("bulgarian")) languages.Add(Language.Bulgarian);
        if (lowerTitle.Contains("polish")) languages.Add(Language.Polish);
        if (lowerTitle.Contains("vietnamese")) languages.Add(Language.Vietnamese);
        if (lowerTitle.Contains("swedish")) languages.Add(Language.Swedish);
        if (lowerTitle.Contains("norwegian")) languages.Add(Language.Norwegian);
        if (lowerTitle.Contains("finnish")) languages.Add(Language.Finnish);
        if (lowerTitle.Contains("turkish")) languages.Add(Language.Turkish);
        if (lowerTitle.Contains("portuguese")) languages.Add(Language.Portuguese);
        if (lowerTitle.Contains("brazilian")) languages.Add(Language.PortugueseBR);
        if (lowerTitle.Contains("hungarian")) languages.Add(Language.Hungarian);
        if (lowerTitle.Contains("hebrew")) languages.Add(Language.Hebrew);
        if (lowerTitle.Contains("ukrainian")) languages.Add(Language.Ukrainian);
        if (lowerTitle.Contains("persian")) languages.Add(Language.Persian);
        if (lowerTitle.Contains("bengali")) languages.Add(Language.Bengali);
        if (lowerTitle.Contains("slovak")) languages.Add(Language.Slovak);
        if (lowerTitle.Contains("latvian")) languages.Add(Language.Latvian);
        if (lowerTitle.Contains("latino")) languages.Add(Language.SpanishLatino);
        if (lowerTitle.Contains("tamil")) languages.Add(Language.Tamil);
        if (lowerTitle.Contains("telugu")) languages.Add(Language.Telugu);
        if (lowerTitle.Contains("malayalam")) languages.Add(Language.Malayalam);
        if (lowerTitle.Contains("kannada")) languages.Add(Language.Kannada);
        if (lowerTitle.Contains("albanian")) languages.Add(Language.Albanian);
        if (lowerTitle.Contains("afrikaans")) languages.Add(Language.Afrikaans);
        if (lowerTitle.Contains("marathi")) languages.Add(Language.Marathi);
        if (lowerTitle.Contains("tagalog")) languages.Add(Language.Tagalog);

        // Case-sensitive regex matches
        var caseSensitiveMatches = CaseSensitiveLanguageRegex.Matches(title);
        foreach (Match match in caseSensitiveMatches)
        {
            if (match.Groups["english"].Success) languages.Add(Language.English);
            if (match.Groups["lithuanian"].Success) languages.Add(Language.Lithuanian);
            if (match.Groups["czech"].Success) languages.Add(Language.Czech);
            if (match.Groups["polish"].Success) languages.Add(Language.Polish);
            if (match.Groups["bulgarian"].Success) languages.Add(Language.Bulgarian);
            if (match.Groups["slovak"].Success) languages.Add(Language.Slovak);
            if (match.Groups["spanish"].Success) languages.Add(Language.Spanish);
            if (match.Groups["german"].Success) languages.Add(Language.German);
        }

        // Case-insensitive regex matches
        var matches = LanguageRegex.Matches(title);
        foreach (Match match in matches)
        {
            if (match.Groups["english"].Success) languages.Add(Language.English);
            if (match.Groups["italian"].Success) languages.Add(Language.Italian);
            if (match.Groups["german"].Success) languages.Add(Language.German);
            if (match.Groups["flemish"].Success) languages.Add(Language.Flemish);
            if (match.Groups["greek"].Success) languages.Add(Language.Greek);
            if (match.Groups["french"].Success) languages.Add(Language.French);
            if (match.Groups["russian"].Success) languages.Add(Language.Russian);
            if (match.Groups["bulgarian"].Success) languages.Add(Language.Bulgarian);
            if (match.Groups["brazilian"].Success) languages.Add(Language.PortugueseBR);
            if (match.Groups["hungarian"].Success) languages.Add(Language.Hungarian);
            if (match.Groups["hebrew"].Success) languages.Add(Language.Hebrew);
            if (match.Groups["polish"].Success) languages.Add(Language.Polish);
            if (match.Groups["chinese"].Success) languages.Add(Language.Chinese);
            if (match.Groups["spanish"].Success) languages.Add(Language.Spanish);
            if (match.Groups["catalan"].Success) languages.Add(Language.Catalan);
            if (match.Groups["ukrainian"].Success) languages.Add(Language.Ukrainian);
            if (match.Groups["latvian"].Success) languages.Add(Language.Latvian);
            if (match.Groups["romanian"].Success) languages.Add(Language.Romanian);
            if (match.Groups["telugu"].Success) languages.Add(Language.Telugu);
            if (match.Groups["vietnamese"].Success) languages.Add(Language.Vietnamese);
            if (match.Groups["japanese"].Success) languages.Add(Language.Japanese);
            if (match.Groups["korean"].Success) languages.Add(Language.Korean);
            if (match.Groups["urdu"].Success) languages.Add(Language.Urdu);
            if (match.Groups["romansh"].Success) languages.Add(Language.Romansh);
            if (match.Groups["mongolian"].Success) languages.Add(Language.Mongolian);
            if (match.Groups["georgian"].Success) languages.Add(Language.Georgian);
            if (match.Groups["original"].Success) languages.Add(Language.Original);
        }

        // Default to Unknown if no languages detected
        if (languages.Count == 0)
        {
            languages.Add(Language.Unknown);
        }

        // German dual-language and multi-language handling
        if (languages.Count == 1 && languages[0] == Language.German)
        {
            if (GermanDualLanguageRegex.IsMatch(title))
            {
                languages.Add(Language.Original);
            }
            else if (GermanMultiLanguageRegex.IsMatch(title))
            {
                languages.Add(Language.Original);
                languages.Add(Language.English);
            }
        }

        // Return distinct languages
        return languages.Distinct().ToList();
    }
}