using Discord;
using Discord.Commands;
using NadekoBot.Attributes;
using NadekoBot.Extensions;
using System;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace NadekoBot.Modules.Utility
{
    public partial class Utility
    {
        [Group]
        public class InfoCommands : ModuleBase
        {
            [NadekoCommand, Usage, Description, Aliases]
            [RequireContext(ContextType.Guild)]
            public async Task ServerInfo(string guildName = null)
            {
                var channel = (ITextChannel)Context.Channel;
                guildName = guildName?.ToUpperInvariant();
                IGuild guild;
                if (string.IsNullOrWhiteSpace(guildName))
                    guild = channel.Guild;
                else
                    guild = NadekoBot.Client.GetGuilds().Where(g => g.Name.ToUpperInvariant() == guildName.ToUpperInvariant()).FirstOrDefault();
                if (guild == null)
                    return;
                var ownername = await guild.GetUserAsync(guild.OwnerId);
                var textchn = (await guild.GetTextChannelsAsync()).Count();
                var voicechn = (await guild.GetVoiceChannelsAsync()).Count();

                var createdAt = new DateTime(2015, 1, 1, 0, 0, 0, 0, DateTimeKind.Utc).AddMilliseconds(guild.Id >> 22);
                var sb = new StringBuilder();
                var users = await guild.GetUsersAsync().ConfigureAwait(false);
                var features = string.Join("\n", guild.Features);
                if (string.IsNullOrWhiteSpace(features))
                    features = "-";
                var embed = new EmbedBuilder()
                    .WithAuthor(eab => eab.WithName("Server Info"))
                    .WithTitle(guild.Name)
                    .AddField(fb => fb.WithName("**ID**").WithValue(guild.Id.ToString()).WithIsInline(true))
                    .AddField(fb => fb.WithName("**Owner**").WithValue(ownername.ToString()).WithIsInline(true))
                    .AddField(fb => fb.WithName("**Members**").WithValue(users.Count.ToString()).WithIsInline(true))
                    .AddField(fb => fb.WithName("**Text Channels**").WithValue(textchn.ToString()).WithIsInline(true))
                    .AddField(fb => fb.WithName("**Voice Channels**").WithValue(voicechn.ToString()).WithIsInline(true))
                    .AddField(fb => fb.WithName("**Created At**").WithValue($"{createdAt.ToString("dd.MM.yyyy HH:mm")}").WithIsInline(true))
                    .AddField(fb => fb.WithName("**Region**").WithValue(guild.VoiceRegionId.ToString()).WithIsInline(true))
                    .AddField(fb => fb.WithName("**Roles**").WithValue((guild.Roles.Count - 1).ToString()).WithIsInline(true))
                    .AddField(fb => fb.WithName("**Features**").WithValue(features).WithIsInline(true))
                    .WithImageUrl(guild.IconUrl)
                    .WithColor(NadekoBot.OkColor);
                if (guild.Emojis.Count() > 0)
                {
                    embed.AddField(fb => fb.WithName("**Custom Emojis**").WithValue(string.Join(" ", guild.Emojis.Select(e => $"{e.Name} <:{e.Name}:{e.Id}>"))));
                }
                await Context.Channel.EmbedAsync(embed).ConfigureAwait(false);
            }

            [NadekoCommand, Usage, Description, Aliases]
            [RequireContext(ContextType.Guild)]
            public async Task ChannelInfo(ITextChannel channel = null)
            {
                var ch = channel ?? (ITextChannel)Context.Channel;
                if (ch == null)
                    return;
                var createdAt = new DateTime(2015, 1, 1, 0, 0, 0, 0, DateTimeKind.Utc).AddMilliseconds(ch.Id >> 22);
                var usercount = (await ch.GetUsersAsync().Flatten()).Count();
                var embed = new EmbedBuilder()
                    .WithTitle(ch.Name)
                    .WithDescription(ch.Topic?.SanitizeMentions())
                    .AddField(fb => fb.WithName("**ID**").WithValue(ch.Id.ToString()).WithIsInline(true))
                    .AddField(fb => fb.WithName("**Created At**").WithValue($"{createdAt.ToString("dd.MM.yyyy HH:mm")}").WithIsInline(true))
                    .AddField(fb => fb.WithName("**Users**").WithValue(usercount.ToString()).WithIsInline(true))
                    .WithColor(NadekoBot.OkColor);
                await Context.Channel.EmbedAsync(embed).ConfigureAwait(false);
            }

            [NadekoCommand, Usage, Description, Aliases]
            [RequireContext(ContextType.Guild)]
            public async Task UserInfo(IGuildUser usr = null)
            {
                var channel = (ITextChannel)Context.Channel;
                var user = usr ?? Context.User as IGuildUser;

                if (user == null)
                    return;

                var embed = new EmbedBuilder()
                    .AddField(fb => fb.WithName("**Name**").WithValue($"**{user.Username}**#{user.Discriminator}").WithIsInline(true));
                if (!string.IsNullOrWhiteSpace(user.Nickname))
                {
                    embed.AddField(fb => fb.WithName("**Nickname**").WithValue(user.Nickname).WithIsInline(true));
                }
                embed.AddField(fb => fb.WithName("**ID**").WithValue(user.Id.ToString()).WithIsInline(true))
                    .AddField(fb => fb.WithName("**Joined Server**").WithValue($"{user.JoinedAt?.ToString("dd.MM.yyyy HH:mm")}").WithIsInline(true))
                    .AddField(fb => fb.WithName("**Joined Discord**").WithValue($"{user.CreatedAt.ToString("dd.MM.yyyy HH:mm")}").WithIsInline(true))
                    .AddField(fb => fb.WithName("**Roles**").WithValue($"**({user.RoleIds.Count - 1})** - {string.Join("\n", user.GetRoles().Where(r => r.Id != r.Guild.EveryoneRole.Id).Select(r => r.Name)).SanitizeMentions()}").WithIsInline(true))
                    .WithThumbnailUrl(user.RealAvatarUrl())
                    .WithColor(NadekoBot.OkColor);
                await Context.Channel.EmbedAsync(embed).ConfigureAwait(false);
            }
        }

        [NadekoCommand, Usage, Description, Aliases]
        [RequireContext(ContextType.Guild)]
        [OwnerOnly]
        public async Task Activity(int page = 1)
        {
            const int activityPerPage = 15;
            page -= 1;

            if (page < 0)
                return;

            int startCount = page * activityPerPage;

            StringBuilder str = new StringBuilder();
            foreach (var kvp in NadekoBot.CommandHandler.UserMessagesSent.OrderByDescending(kvp => kvp.Value).Skip(page*activityPerPage).Take(activityPerPage))
            {
                str.AppendLine($"`{++startCount}.` **{kvp.Key}** [{kvp.Value/NadekoBot.Stats.GetUptime().TotalSeconds:F2}/s] - {kvp.Value} total");
            }

            await Context.Channel.EmbedAsync(new EmbedBuilder().WithTitle($"Activity Page #{page}")
                .WithOkColor()
                .WithFooter(efb => efb.WithText($"{NadekoBot.CommandHandler.UserMessagesSent.Count} users total."))
                .WithDescription(str.ToString()));
        }
    }
}