using System.Net.Http.Json;
using System.Text;
using System.Text.Json;
using System.Text.Json.Serialization;
using System.Web;
using ArcaneLibs.Extensions;
using LibMatrix.Extensions;
using LibMatrix.Responses;
using LibMatrix.Services;

namespace LibMatrix.Homeservers;

public class RemoteHomeserver {
    public RemoteHomeserver(string serverName, HomeserverResolverService.WellKnownUris wellKnownUris, string? proxy) {
        if (string.IsNullOrWhiteSpace(proxy))
            proxy = null;
        ServerNameOrUrl = serverName;
        WellKnownUris = wellKnownUris;
        ClientHttpClient = new MatrixHttpClient {
            BaseAddress = new Uri(proxy?.TrimEnd('/') ?? wellKnownUris.Client?.TrimEnd('/') ?? throw new InvalidOperationException($"No client URI for {serverName}!")),
            // Timeout = TimeSpan.FromSeconds(300) // TODO: Re-implement this
        };

        if (proxy is not null) ClientHttpClient.DefaultRequestHeaders.Add("MXAE_UPSTREAM", serverName);
        if (!string.IsNullOrWhiteSpace(wellKnownUris.Server))
            FederationClient = new FederationClient(WellKnownUris.Server!, proxy);
        Auth = new(this);
    }

    private Dictionary<string, object> _profileCache { get; set; } = new();
    public string ServerNameOrUrl { get; }

    [JsonIgnore]
    public MatrixHttpClient ClientHttpClient { get; set; }

    [JsonIgnore]
    public FederationClient? FederationClient { get; set; }

    public HomeserverResolverService.WellKnownUris WellKnownUris { get; set; }

    public async Task<UserProfileResponse> GetProfileAsync(string mxid, bool useCache = false) {
        if (mxid is null) throw new ArgumentNullException(nameof(mxid));
        if (useCache && _profileCache.TryGetValue(mxid, out var value)) {
            if (value is SemaphoreSlim s) await s.WaitAsync();
            if (value is UserProfileResponse p) return p;
        }

        _profileCache[mxid] = new SemaphoreSlim(1);

        var resp = await ClientHttpClient.GetAsync($"/_matrix/client/v3/profile/{HttpUtility.UrlEncode(mxid)}");
        var data = await resp.Content.ReadFromJsonAsync<UserProfileResponse>();
        if (!resp.IsSuccessStatusCode) Console.WriteLine("Profile: " + data);
        _profileCache[mxid] = data ?? throw new InvalidOperationException($"Could not get profile for {mxid}");

        return data;
    }

    public async Task<ClientVersionsResponse> GetClientVersionsAsync() {
        var resp = await ClientHttpClient.GetAsync($"/_matrix/client/versions");
        var data = await resp.Content.ReadFromJsonAsync<ClientVersionsResponse>();
        if (!resp.IsSuccessStatusCode) Console.WriteLine("ClientVersions: " + data);
        return data ?? throw new InvalidOperationException("ClientVersionsResponse is null");
    }

    public async Task<AliasResult> ResolveRoomAliasAsync(string alias) {
        var resp = await ClientHttpClient.GetAsync($"/_matrix/client/v3/directory/room/{alias.Replace("#", "%23")}");
        var data = await resp.Content.ReadFromJsonAsync<AliasResult>();
        //var text = await resp.Content.ReadAsStringAsync();
        if (!resp.IsSuccessStatusCode) Console.WriteLine("ResolveAlias: " + data.ToJson());
        return data ?? throw new InvalidOperationException($"Could not resolve alias {alias}");
    }

    public Task<PublicRoomDirectoryResult> GetPublicRoomsAsync(int limit = 100, string? server = null, string? since = null) =>
        ClientHttpClient.GetFromJsonAsync<PublicRoomDirectoryResult>(buildUriWithParams("/_matrix/client/v3/publicRooms", (nameof(limit), true, limit),
            (nameof(server), !string.IsNullOrWhiteSpace(server), server), (nameof(since), !string.IsNullOrWhiteSpace(since), since)));

    // TODO: move this somewhere else
    private string buildUriWithParams(string url, params (string name, bool include, object? value)[] values) {
        return url + "?" + string.Join("&", values.Where(x => x.include));
    }

#region Authentication

    public async Task<LoginResponse> LoginAsync(string username, string password, string? deviceName = null) {
        var resp = await ClientHttpClient.PostAsJsonAsync("/_matrix/client/r0/login", new {
            type = "m.login.password",
            identifier = new {
                type = "m.id.user",
                user = username
            },
            password,
            initial_device_display_name = deviceName
        });
        var data = await resp.Content.ReadFromJsonAsync<LoginResponse>();
        return data ?? throw new InvalidOperationException("LoginResponse is null");
    }

    public async Task<LoginResponse> RegisterAsync(string username, string password, string? deviceName = null) {
        var resp = await ClientHttpClient.PostAsJsonAsync("/_matrix/client/r0/register", new {
            kind = "user",
            auth = new {
                type = "m.login.dummy"
            },
            username,
            password,
            initial_device_display_name = deviceName ?? "LibMatrix"
        }, new JsonSerializerOptions() {
            DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingNull
        });
        var data = await resp.Content.ReadFromJsonAsync<LoginResponse>();
        return data ?? throw new InvalidOperationException("LoginResponse is null");
    }

#endregion

    [Obsolete("This call uses the deprecated unauthenticated media endpoints, please switch to the relevant AuthenticatedHomeserver methods instead.", true)]
    public virtual string? ResolveMediaUri(string? mxcUri) => null;

    public UserInteractiveAuthClient Auth;
}

public class PublicRoomDirectoryResult {
    [JsonPropertyName("chunk")]
    public List<PublicRoomListItem> Chunk { get; set; }

    [JsonPropertyName("next_batch")]
    public string? NextBatch { get; set; }

    [JsonPropertyName("prev_batch")]
    public string? PrevBatch { get; set; }

    [JsonPropertyName("total_room_count_estimate")]
    public int TotalRoomCountEstimate { get; set; }

    public class PublicRoomListItem {
        [JsonPropertyName("avatar_url")]
        public string? AvatarUrl { get; set; }

        [JsonPropertyName("canonical_alias")]
        public string? CanonicalAlias { get; set; }

        [JsonPropertyName("guest_can_join")]
        public bool GuestCanJoin { get; set; }

        [JsonPropertyName("join_rule")]
        public string JoinRule { get; set; }

        [JsonPropertyName("name")]
        public string? Name { get; set; }

        [JsonPropertyName("num_joined_members")]
        public int NumJoinedMembers { get; set; }

        [JsonPropertyName("room_id")]
        public string RoomId { get; set; }

        [JsonPropertyName("topic")]
        public string? Topic { get; set; }

        [JsonPropertyName("world_readable")]
        public bool WorldReadable { get; set; }
    }
}

public class AliasResult {
    [JsonPropertyName("room_id")]
    public string RoomId { get; set; }

    [JsonPropertyName("servers")]
    public List<string> Servers { get; set; }
}