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/>");
}