using Discord;
using Discord.Commands;
using System;
using System.Collections.Generic;
using System.Text;
using System.Threading.Tasks;
using System.Linq;
using EventBot.Attributes;
using EventBot.Services;
using Discord.Addons.Interactive;
using EventBot.Misc;

namespace EventBot.Modules
{
    public class BasicModule : ModuleBase<SocketCommandContext>
    {
        private readonly DatabaseService _database;
        public BasicModule(DatabaseService database)
        {
            _database = database;
        }

        [RequireUserPermission(GuildPermission.Administrator, Group = "Permission")]
        [RequireOwner(Group = "Permission")]
        [RequireContext(ContextType.Guild)]
        [Command("prefix")]
        [Name("Configure prefix")]
        [Summary("Gets prefix.")]
        public async Task PrefixCommand()
        {
            var guildConfig = _database.GuildConfigs.FirstOrDefault(g => g.GuildId == Context.Guild.Id);
            if (guildConfig == null)
                throw new Exception("No guild config was foumd.");
            if(guildConfig.Prefix != null)
                await ReplyAsync($"Current prefix is `{guildConfig.Prefix}`");
            else
                await ReplyAsync($"There is no prefix set for this guild.");
        }

        [RequireUserPermission(GuildPermission.Administrator, Group = "Permission")]
        [RequireOwner(Group = "Permission")]
        [RequireContext(ContextType.Guild)]
        [Command("prefix")]
        [Name("Configure prefix")]
        [Summary("Sets prefix.")]
        public async Task PrefixCommand(
            [Summary("New prefix to set")] string newPrefix)
        {
            var guildConfig = _database.GuildConfigs.FirstOrDefault(g => g.GuildId == Context.Guild.Id);
            if (guildConfig == null)
                throw new Exception("No guild config was foumd.");
            guildConfig.Prefix = newPrefix;
            await _database.SaveChangesAsync();
            await ReplyAsync($"Prefix has been set to `{guildConfig.Prefix}`");
        }


        [Group("help")]
        public class HelpModule : InteractiveBase<SocketCommandContext>
        {

            private readonly CommandService _commands;
            public HelpModule(CommandService commands)
            {
                _commands = commands;
            }

            [Command]
            [Name("Help")]
            [Summary("Lists all commands with there descriptions.")]
            public async Task DefaultHelpAsync()
            {
                var pagedCommands = _commands.Commands
                    .OrderBy(c => c.Aliases[0])
                    .Where(c => c.Attributes
                        .Select(a =>
                        {
                            switch (a)
                            {
                                case NoHelpAttribute _:
                                    return false;
                                case RequireContextAttribute rc:
                                    return Context.IsContextType(rc.Contexts);
                                default:
                                    return true;
                            }
                        })
                        .Aggregate(true, (a, r) => a && r))
                    .SelectMany(c => c.Aliases.Select(a => new { CI = c, MA = (c.Aliases[0] == a), A = a }).Reverse())
                    .Select((e, i) => new { Command = e, Index = i })
                    .GroupBy(o => o.Index / 30)
                    .Select(g => g.Select(o => o.Command));

                var pager = new PaginatedMessage()
                {
                    Title = "Command list",
                    Color = Color.DarkBlue,
                    Pages = pagedCommands.Select(p => string.Join("\r\n", p.Select(c =>
                    {
                        if (c.MA)
                            return $"`{c.CI.FormatCallHelpString()}` - **{c.CI.Name}**";
                        else
                            return $"`{c.A}` `↪`";
                    }))),
                    Options = new PaginatedAppearanceOptions()
                    {
                        Info = null,
                        JumpDisplayOptions = JumpDisplayOptions.Never
                    }
                };
                await PagedReplyAsync(pager);
            }

            [Command]
            [Name("Help")]
            [Summary("Shows detailed info about command.")]
            public async Task DefaultHelpAsync([Summary("Command ")][Remainder] string commandAlias)
            {
                var command = _commands.Commands.Where(c => c.Aliases.Contains(commandAlias)).FirstOrDefault();
                if (command == null)
                    throw new Exception("This command was not found.");
                var embed = new EmbedBuilder()
                    .WithTitle(command.Name)
                    .WithDescription(command.Summary)
                    .WithColor(Color.DarkTeal);
                embed.AddField("Module", command.Module.Name, true);
                if (command.Aliases.Count > 1)
                    embed.AddField("Aliases", string.Join(", ", command.Aliases));
                if(command.Parameters.Count > 0)
                    embed.AddField("Parameters",
                        string.Join("\r\n", command.Parameters.Select(p => $"`{p.FormatParameter()}` *(Type: {p.FormatParameterType()})* - **{p.Summary}** {(p.IsRemainder ? "_No quotes are needed, when providing this parameter._" : "")}" ))
                    );

                await ReplyAsync($"I got this information about command `{commandAlias}`:", embed: embed.Build());
            }

            [Command("types")]
            [Name("Type help")]
            [Priority(1)]
            [Summary("Shows information about avaivable types for command paramters.")]
            [NoHelp]
            public async Task TypeHelp()
            {
                await ReplyAsync($"There are following avaivable types for command input: \r\n" +
                    $"***String*** - The most basic text input, must be qouted if there is space inside. Ex: `\"This is a string\"`; `ThisCanBeUsedAlsoAsString`\r\n" +
                    $"***Number*** - Just a simple number. Ex: `1`; `-2`; `1523`\r\n" +
                    $"***User*** - Mention or ID of user. Ex: `360710685186850826`; `Skull132#1984`; {Context.Client.CurrentUser.Mention}\r\n" +
                    $"***Event*** - ID of event. Just positive numbers 🙂.\r\n" +
                    $"***EventRole*** - ID of event's role. Also positive numbers 😊.\r\n" +
                    $"***EventParticipactionType*** - What type you want. Ex: `Quick`; `Detailed`");
            }
        }
    }
}