namespace Bot.Dialogs
{
    using Microsoft.Bot.Builder;
    using Microsoft.Bot.Builder.Dialogs;
    using Microsoft.Bot.Schema;
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Threading;
    using System.Threading.Tasks;

    public class HTMLPromptResult
    {
        public string Format { get; set; }
        public string Text { get; set; }
    }

    public class HTMLPrompt : Prompt<HTMLPromptResult>
    {
        public HTMLPrompt(string dialogId, PromptValidator<HTMLPromptResult> validator = null) : base(dialogId, validator)
        {
        }

        protected override async Task OnPromptAsync(ITurnContext turnContext, IDictionary<string, object> state, PromptOptions options, bool isRetry, CancellationToken cancellationToken = default)
        {
            if (turnContext == null)
            {
                throw new ArgumentNullException(nameof(turnContext));
            }

            if (options == null)
            {
                throw new ArgumentNullException(nameof(options));
            }

            if (isRetry && options.RetryPrompt != null)
            {
                await turnContext.SendActivityAsync(options.RetryPrompt, cancellationToken).ConfigureAwait(false);
            }
            else if (options.Prompt != null)
            {
                await turnContext.SendActivityAsync(options.Prompt, cancellationToken).ConfigureAwait(false);
            }
        }

        protected override Task<PromptRecognizerResult<HTMLPromptResult>> OnRecognizeAsync(ITurnContext turnContext, IDictionary<string, object> state, PromptOptions options, CancellationToken cancellationToken = default)
        {
            if (turnContext == null)
            {
                throw new ArgumentNullException(nameof(turnContext));
            }

            var result = new PromptRecognizerResult<HTMLPromptResult>();
            HTMLPromptResult htmlResult = new HTMLPromptResult();

            if (turnContext.Activity.Type == ActivityTypes.Message)
            {
                var message = turnContext.Activity.AsMessageActivity();
                var attachment = message.Attachments?.Where(a => a.ContentType.Equals("text/html"))?.FirstOrDefault();
                if (attachment?.Content != null)
                {
                    htmlResult.Format = attachment.ContentType;
                    htmlResult.Text = attachment.Content.ToString();
                    result.Succeeded = true;
                    result.Value = htmlResult;
                }
                else if (message.Text != null)
                {
                    htmlResult.Format = message.TextFormat;
                    htmlResult.Text = message.Text;
                    result.Succeeded = true;
                    result.Value = htmlResult;
                }
            }

            return Task.FromResult(result);
        }
    }
}