using System;
using System.Collections.Generic;


public static class NameserverRedirect
{













    private static readonly Dictionary<string, string> ServicePrefixes = new(StringComparer.OrdinalIgnoreCase)
    {
        ["api.rec.net"] = "",
        ["cdn.rec.net"] = "",
        ["images.rec.net"] = "/images",
        ["img.rec.net"] = "/images",
        ["data.rec.net"] = "/data",
        ["storage.rec.net"] = "/storage",
        ["notify.rec.net"] = "/notify",
        ["notifications.rec.net"] = "/notify",
        ["notify.radicade.internal"] = "/notify",
        ["notifications.radicade.internal"] = "/notify",
        ["auth.rec.net"] = "/auth",
        ["accounts.rec.net"] = "/accounts",
        ["rooms.rec.net"] = "/rooms",
        ["matchmaking.rec.net"] = "/matchmaking",
        ["chat.rec.net"] = "/chat",

        ["api.radicade.app"] = "",
        ["cdn.radicade.app"] = "/cdn",
        ["ai.radicade.app"] = "/ai",
        ["auth.radicade.app"] = "/auth",
        ["www.radicade.app"] = "/www",
        ["cards.radicade.app"] = "/cards",
        ["notifications.radicade.app"] = "/notify",
        ["images.radicade.app"] = "/images",
        ["commerce.radicade.app"] = "/commerce",
        ["data.radicade.app"] = "/data",
        ["datacollection.radicade.app"] = "/datacollection",
        ["discovery.radicade.app"] = "/discovery",
        ["matchmaking.radicade.app"] = "/matchmaking",
        ["storage.radicade.app"] = "/storage",
        ["chat.radicade.app"] = "/chat",
        ["geo.radicade.app"] = "/geo",
        ["leaderboard.radicade.app"] = "/leaderboard",
        ["accounts.radicade.app"] = "/accounts",
        ["link.radicade.app"] = "/link",
        ["locker.radicade.app"] = "/locker",
        ["moderation.radicade.app"] = "/moderation",
        ["roomcomments.radicade.app"] = "/roomcomments",
        ["roomieintegrations.radicade.app"] = "/roomieintegrations",
        ["clubs.radicade.app"] = "/clubs",
        ["rooms.radicade.app"] = "/rooms",
        ["econ.radicade.app"] = "/econ",
        ["bugreporting.radicade.app"] = "/bugreporting",
        ["cms.radicade.app"] = "/cms",
        ["gamelogs.radicade.app"] = "/gamelogs",
        ["platformnotifications.radicade.app"] = "/platformnotifications",
        ["stringscdn.radicade.app"] = "/stringscdn",
        ["strings.radicade.app"] = "/strings",
        ["lists.radicade.app"] = "/lists",
        ["playersettings.radicade.app"] = "/playersettings",
        ["studio.radicade.app"] = "/studio",
        ["studiocdn.radicade.app"] = "/studiocdn",
        ["thorn.radicade.app"] = "/thorn",
        ["videos.radicade.app"] = "/videos",
    };

    public static string Rewrite(string requestUrl, string serverUrl)
    {
        if (!Uri.TryCreate(requestUrl, UriKind.Absolute, out var request) ||
            (request.Scheme != "http" && request.Scheme != "https"))
            return requestUrl;


        bool nameserver = request.Host.Equals("ns.rec.net", StringComparison.OrdinalIgnoreCase) ||
            request.Host.Equals("ns.radicade.internal", StringComparison.OrdinalIgnoreCase);
        bool patchedServer = request.Host.Equals("ns.radicade.app", StringComparison.OrdinalIgnoreCase);

        ServicePrefixes.TryGetValue(request.Host, out var servicePrefix);

        if (!nameserver && !patchedServer && servicePrefix == null)
            return requestUrl;

        if (!Uri.TryCreate(serverUrl, UriKind.Absolute, out var server) ||
            (server.Scheme != "http" && server.Scheme != "https") ||
            !string.IsNullOrEmpty(server.UserInfo) || !string.IsNullOrEmpty(server.Query) ||
            !string.IsNullOrEmpty(server.Fragment))
            throw new ArgumentException("Connection.ServerUrl must be an HTTP(S) base URL without credentials, query or fragment.", nameof(serverUrl));

        var path = request.AbsolutePath;

        if (nameserver)
        {

            if (path == "/") path = "/ns";
        }
        else if (servicePrefix is { Length: > 0 })
        {


            if (servicePrefix == "/notify" && path.StartsWith("/notify/", StringComparison.OrdinalIgnoreCase))
                path = path.Substring("/notify".Length);
            else if (path.StartsWith("/images/", StringComparison.OrdinalIgnoreCase))
                path = path.Substring("/images".Length);
            else if (path.StartsWith("/img/", StringComparison.OrdinalIgnoreCase))
                path = path.Substring("/img".Length);

            path = servicePrefix + path;
        }

        return server.AbsoluteUri.TrimEnd('/') + path + request.Query;
    }

        public static string RewriteWebSocket(string requestUrl, string serverUrl)
    {
        if (!Uri.TryCreate(requestUrl, UriKind.Absolute, out var request))
            return requestUrl;

        var scheme = request.Scheme.ToLowerInvariant();
        var secure = scheme == "wss" || scheme == "https";
        if (scheme != "ws" && scheme != "wss" && scheme != "http" && scheme != "https")
            return requestUrl;



        var asHttp = new UriBuilder(request) { Scheme = secure ? "https" : "http" }.Uri.AbsoluteUri;
        var rewritten = Rewrite(asHttp, serverUrl);
        if (rewritten == asHttp) return requestUrl;

        if (!Uri.TryCreate(rewritten, UriKind.Absolute, out var result)) return requestUrl;
        return new UriBuilder(result) { Scheme = result.Scheme == "https" ? "wss" : "ws" }.Uri.AbsoluteUri;
    }

        public static bool IsHubUrl(string url)
    {
        if (string.IsNullOrWhiteSpace(url)) return false;

        var lower = url.ToLowerInvariant();
        var query = lower.IndexOf('?');
        var path = query < 0 ? lower : lower.Substring(0, query);

        return path.Contains("/hub/v1") || path.EndsWith("/hub")
            || path.Contains("/hub/")
            || path.Contains("notifyhub")
            || path.Contains("/notify/hub");
    }

        public static bool HasHubToken(string url)
    {
        if (string.IsNullOrWhiteSpace(url)) return false;

        var query = url.IndexOf('?');
        if (query < 0) return false;

        foreach (var pair in url.Substring(query + 1).Split('&'))
        {
            var equals = pair.IndexOf('=');
            if (equals <= 0 || equals + 1 >= pair.Length) continue;
            if (pair.Substring(0, equals).Equals("access_token", StringComparison.OrdinalIgnoreCase)) return true;
        }

        return false;
    }

        public static string EnsureHubToken(string url, string token)
    {
        if (!IsHubUrl(url)) return url;
        if (HasHubToken(url)) return url;
        if (string.IsNullOrWhiteSpace(token)) return url;

        var raw = token.Trim();
        if (raw.StartsWith("Bearer ", StringComparison.OrdinalIgnoreCase)) raw = raw.Substring(7).Trim();
        else if (raw.Equals("Bearer", StringComparison.OrdinalIgnoreCase)) raw = string.Empty;
        if (raw.Length == 0) return url;



        var query = url.IndexOf('?');
        var basePart = query < 0 ? url : url.Substring(0, query);
        var rest = query < 0 ? string.Empty : url.Substring(query + 1).TrimStart('&');
        var accessToken = "access_token=" + Uri.EscapeDataString(raw);

        return basePart + "?" + accessToken + (rest.Length == 0 ? string.Empty : "&" + rest);
    }
}