archived-discord-bot/CompatBot/Commands/BotMath.cs

using System;
using System.Globalization;
using System.Threading.Tasks;
using CompatBot.Commands.Attributes;
using DSharpPlus.CommandsNext;
using DSharpPlus.CommandsNext.Attributes;
using org.mariuszgromada.math.mxparser;

namespace CompatBot.Commands
{
    [Group("math")]
    [Description("Math, here you go Juhn. Use `math help` for syntax help")]
    internal sealed class BotMath : BaseCommandModuleCustom
    {
        [GroupCommand, Priority(9)]
        public async Task Expression(CommandContext ctx, [RemainingText, Description("Math expression")] string expression)
        {
            if (string.IsNullOrEmpty(expression))
            {
                try
                {
                    if (ctx.CommandsNext.FindCommand("math help", out _) is Command helpCmd)
                    {
                        var helpCtx = ctx.CommandsNext.CreateContext(ctx.Message, ctx.Prefix, helpCmd);
                        await helpCmd.ExecuteAsync(helpCtx).ConfigureAwait(false);
                    }
                }
                catch { }
                return;
            }

            var result = @"Something went wrong ¯\\_(ツ)\_/¯" + "\nMath is hard, yo";
            try
            {
                var expr = new Expression(expression);
                result = expr.calculate().ToString(CultureInfo.InvariantCulture);
            }
            catch (Exception e)
            {
                Config.Log.Warn(e, "Math failed");
            }
            await ctx.Channel.SendMessageAsync(result).ConfigureAwait(false);
        }

        [Command("help"), LimitedToSpamChannel, Cooldown(1, 5, CooldownBucketType.Channel)]
        [Description("General math expression help, or description of specific math word")]
        public Task Help(CommandContext ctx)
            => ctx.Channel.SendMessageAsync("Help for all the features and built-in constants and functions could be found at <https://mathparser.org/mxparser-math-collection/>");
    }
}