using System.Collections.Generic;
using System.ComponentModel;
using Newtonsoft.Json;
using System.Net.Http.Json;

// https://tt-rss.org/wiki/ApiReference

namespace ttrss_co_client.ttrss
{
    public class ApiClient
    {
        public Uri BaseURI { get; private set; }
        private HttpClient httpClient { get; set; }
        private string SessionId { get; set; } = null;
        private int api_level { get; set; }

        public ApiClient(Uri baseUri)
        {
            BaseURI = baseUri;
            httpClient = new HttpClient() { BaseAddress = baseUri };
        }

        public async Task Login(string username, string password)
        {
            var json = new
            {
                op = "login",
                user = username,
                password = password
            };
            var content = JsonContent.Create(json);
            var response = await (await httpClient.PostAsync(BaseURI, content)).Content.ReadAsStringAsync();
            var loginResult = JsonConvert.DeserializeObject<ttrss.messages.LoginResponse>(response);
            if (loginResult.status == 0)
            {
                SessionId = loginResult.content.session_id;
                api_level = loginResult.content.api_level ?? 1;
                Console.WriteLine(SessionId);
            }
            else
            {
                throw new NotImplementedException();
            }
        }

        public async Task<int> GetApiLevel()
        {
            assertInitialized();
            return await oneValueGet<int>("getApiLevel", "level");
        }

        public async Task<bool> Logout()
        {
            assertInitialized();

            return (await oneValueGet<string>("logout", "status"))?.ToLower() == "ok";
        }
        public async Task<bool> IsLoggedIn()
        {
            //assertInitialized();
            return (await oneValueGet<bool>("isLoggedIn", "status"));
        }
        public async Task<int> GetUnread()
        {
            assertInitialized();
            return await oneValueGet<int>("getUnread", "unread");
        }

        public async Task GetFeeds(int cat_id, bool unread_only, int limit, int offset, bool include_nested)
        {
            assertInitialized();
            throw new NotImplementedException();
        }
        public async Task GetCategories(bool unread_only, bool enable_nested, bool include_empty)
        {
            assertInitialized();
            throw new NotImplementedException();
        }
        public enum VIEWMODE { All, Unread, Adaptive, Marked, Updated }
        public enum SORTORDER { Default, OldestFirst, NewestFirst }
        public async Task GetHeadlines(int feed_id, int limit, int skip, /*string filter, */ bool is_cat, bool show_excerpt, bool show_content, VIEWMODE view_mode, bool include_attachments, int since_id, bool include_nested, SORTORDER order_by, bool sanitize, bool force_update = false, bool has_sandbox = false, bool include_header = false)
        {
            await getHeadlines(feed_id, null, limit, skip, /*filter, */ is_cat, show_excerpt, show_content, view_mode, include_attachments, since_id, include_nested, order_by, sanitize, force_update, has_sandbox, include_header);
        }
        public async Task GetHeadlines(string feed_id, int limit, int skip, /*string filter, */ bool is_cat, bool show_excerpt, bool show_content, VIEWMODE view_mode, bool include_attachments, int since_id, bool include_nested, SORTORDER order_by, bool sanitize, bool force_update = false, bool has_sandbox = false, bool include_header = false)
        {
            await getHeadlines(null, feed_id, limit, skip, /*filter, */ is_cat, show_excerpt, show_content, view_mode, include_attachments, since_id, include_nested, order_by, sanitize, force_update, has_sandbox, include_header);
        }
        private async Task getHeadlines(int? int_feed_id, string string_feed_id, int limit, int skip, /*string filter, */ bool is_cat, bool show_excerpt, bool show_content, VIEWMODE view_mode, bool include_attachments, int since_id, bool include_nested, SORTORDER order_by, bool sanitize, bool force_update, bool has_sandbox, bool include_header)
        {
            assertInitialized();
            throw new NotImplementedException();
        }
        public enum UPDATEMODE { SetFalse, SetTrue, Toggle }
        public enum UPDATEFIELD { starred, published, unread }
        public async Task<int> UpdateArticleField(UPDATEMODE mode, UPDATEFIELD field, params int[] ids)
        {
            //documentation: UpdateArticle - for note, we have a separate method UpdateArticleNote
            assertInitialized();
            throw new NotImplementedException();
        }
        public async Task<int> UpdateArticleNote(string data, params int[] ids)
        {
            //documentation: UpdateArticle - for fields other than note, we have a separate method UpdateArticleField
            assertInitialized();
            throw new NotImplementedException();
        }
        public async Task<IEnumerable<object>> GetArticle(params int[] article_id)
        {
            if (!article_id.Any())
            {
                throw new ArgumentException("need at least one article_id");
            }
            assertInitialized();
            throw new NotImplementedException();
        }
        public async Task<Configuration> GetConfig()
        {
            assertInitialized();
            throw new NotImplementedException();
        }
        ///<summary>
        ///tell the feed to update. As opposed to updating our configuration of the feed.
        ///</summary>
        public async Task UpdateFeed(int feed_id)
        {
            assertInitialized();
            throw new NotImplementedException();
        }
        public async Task<string> GetPref(string key)
        {
            assertInitialized();
            throw new NotImplementedException();
        }
        public enum CATCHUPMODE { All, OneDay, OneWeek, TwoWeeks }
        public async Task CatchupFeed(int feed_id, bool is_cat, CATCHUPMODE mode = CATCHUPMODE.All)
        {
            assertInitialized();
            throw new NotImplementedException();
        }
        public async Task GetCounters(bool actual_feeds = true, bool labels = true, bool categories = true, bool tags = false)
        {
            assertInitialized();
            throw new NotImplementedException();
        }
        public async Task GetLabels(int? article_id)
        {
            assertInitialized();
            if (article_id != null)
            {
                assertApiLevel(5);
            }
            throw new NotImplementedException();
        }
        public async Task SetArticleLabel(int label_id, bool assign, params int[] article_ids)
        {
            //there's a label "cache", i guess?
            assertInitialized();
            throw new NotImplementedException();
        }
        public async Task ShareToPublished(string title, Uri url, string content, bool sanitize = true)
        {
            assertInitialized();
            assertApiLevel(4);
            if (!sanitize)
                assertApiLevel(20);
            throw new NotImplementedException();
        }
        ///<summary>
        ///<param name="login"/>if the feed requires basic HTTP auth; the login. (decidedly not self-explanatory, gdi)</param>
        ///<param name="password"/>if the feed requires basic HTTP auth; the password. (decidedly not self-explanatory, gdi)</param>
        ///</summary>
        public async Task SubscribeToFeed(Uri feed_url, int category_id, string login, string password)
        {
            assertInitialized();
            assertApiLevel(5);
            throw new NotImplementedException();
        }
        public async Task UnsubscribeFeed()
        {
            assertInitialized();
            assertApiLevel(5);
            throw new NotImplementedException();
        }
        public async Task GetFeedTree()
        {
            assertInitialized();
            assertApiLevel(5);
            throw new NotImplementedException();
        }
        private void assertInitialized()
        {
            if (SessionId == null)
            {
                throw new InvalidOperationException("no session ID - call Login first!");
            }
        }
        private void assertApiLevel(int ApiLevel)
        {
            if (ApiLevel > this.api_level)
            {
                throw new NotSupportedException($"method requires api level {ApiLevel}, have {this.api_level}");
            }
        }


        private async Task<T> oneValueGet<T>(string op, string key)
        {
            //mostly you post {"op": "aThingToDo", "sid": "sessionId", "some other param": "some other value"}
            //and get back something like {"seq": 0, "status", "content": {"the value you asked for": 0}}
            var json = JsonContent.Create(new
            {
                op = op,
                sid = this.SessionId
            });
            var response = await (await httpClient.PostAsync(BaseURI, json)).Content.ReadAsStringAsync();
            var apiResult = JsonConvert.DeserializeObject<ttrss.messages.GenericApiResponse>(response);
            try
            {
                var converter = TypeDescriptor.GetConverter(typeof(T));
                if (converter != null)
                {
                    return (T)converter.ConvertFromString(apiResult.Content[key]);
                }
                return default(T);
            }
            catch (NotSupportedException)
            {
                return default(T);
            }
        }
    }
}