using System;
using System.Collections.Generic;
using System.Text.RegularExpressions;
using System.Threading.Tasks;
using Gallery.Util;
using Gallery.Util.Interface;
using Gallery.Util.Model;
using Xamarin.Forms;

namespace Gallery.Sources.Gelbooru
{
    public class GallerySource : GallerySourceBase
    {
        public override string Name => "Gelbooru";
        public override string Route => "gelbooru";
        public override string FlyoutIconKey => "Gelbooru";
        public override string HomePage => "https://gelbooru.com";

        public override async Task<IEnumerable<GalleryItem>> GetRecentItemsAsync(int page)
        {
            var offset = (page - 1) * 42;
            var url = $"https://gelbooru.com/index.php?page=post&s=list&tags=all&pid={offset}";
            var (result, error) = await NetHelper.RequestObject(url, @return: content => ResolveGalleryItems(content));

            if (result == null || !string.IsNullOrEmpty(error))
            {
                Log.Error("gelbooru.content.load", $"failed to load content array, error: {error}");
                return null;
            }

            return result;
        }

        private GalleryItem[] ResolveGalleryItems(string content)
        {
            var regex = new Regex(
                @"<article(.|\n)+?<a id=""p(\d+?)"" href=""([^""]+?)"">(.|\n)+?<img src=""([^""]+?)"" title=""([^""]+?)""",
                RegexOptions.Multiline);
            var matches = regex.Matches(content);
            var items = new GalleryItem[matches.Count];
            for (var i = 0; i < items.Length; i++)
            {
                var g = matches[i].Groups;
                items[i] = new GalleryItem(int.Parse(g[2].Value))
                {
                    RawUrl = g[3].Value.Replace("&amp;", "&"),
                    PreviewUrl = g[5].Value,
                    Tags = g[6].Value.Split(' '),
                    Source = Route,
                    IsRawPage = true
                };
            }
            return items;
        }

        public override async Task<string> ResolveImageUrl(GalleryItem item)
        {
            var (result, error) = await NetHelper.RequestObject(item.RawUrl, @return: content =>
            {
                var regex = new Regex(
                    @"<section class=""image-container.+?" +    // data-id=""(\d+?)"".+?data-tags=""([^""]+?)"".+?
                    @"data-width=""(\d+?)"" data-height=""(\d+?)"".+?data-uploader-id=""([^""]*?)"" " +
                    @"data-normalized-source=""([^""]+?)""(.|\n)*?<img .*?src=""([^""]+?)""",
                    RegexOptions.Multiline);
                var m = regex.Match(content);
                if (m.Success)
                {
                    var g = m.Groups;
                    item.Width = int.Parse(g[1].Value);
                    item.Height = int.Parse(g[2].Value);
                    item.UserId = g[3].Value;
                    item.SourceUrl = g[4].Value;
                    item.RawUrl = g[6].Value;
                    return item.RawUrl;
                }
                return null;
            });

            if (result == null || !string.IsNullOrEmpty(error))
            {
                Log.Error("gelbooru.imageUrl.resolve", $"failed to load data, error: {error}");
                return null;
            }

            return result;
        }

        public override void SetCookie()
        {
            throw new NotImplementedException();
        }

        public override void InitDynamicResources(string family, ResourceDictionary light, ResourceDictionary dark)
        {
            var icon = new FontImageSource
            {
                FontFamily = family,
                Glyph = "\uf5d2",
                Size = 18.0
            };
            light.Add(FlyoutIconKey, icon);
            dark.Add(FlyoutIconKey, icon);
        }
    }
}