// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
 
using Microsoft.DotNet.Interactive;
using System.Collections.Generic;
using Microsoft.Data.Analysis;
using System;
using System.Threading.Tasks;
using System.Text.Json;
using System.Threading;
 
namespace Microsoft.ML.AutoML
{
    public class NotebookMonitor : IMonitor
    {
        private readonly ActionThrottler _updateThrottler;
        private DisplayedValue _valueToUpdate;
 
        public SweepablePipeline SweepablePipeline { get; private set; }
        public TrialResult BestTrial { get; set; }
        public TrialResult MostRecentTrial { get; set; }
        public TrialSettings ActiveTrial { get; set; }
        public List<TrialResult> CompletedTrials { get; set; }
        public DataFrame TrialData { get; set; }
 
        public NotebookMonitor(SweepablePipeline pipeline)
        {
            CompletedTrials = new List<TrialResult>();
            TrialData = new DataFrame(new PrimitiveDataFrameColumn<int>("Trial"), new PrimitiveDataFrameColumn<float>("Metric"), new StringDataFrameColumn("Trainer"), new StringDataFrameColumn("Parameters"));
            _updateThrottler = new ActionThrottler(Update, TimeSpan.FromSeconds(5));
            SweepablePipeline = pipeline;
        }
 
        public void ReportBestTrial(TrialResult result)
        {
            BestTrial = result;
 
            ThrottledUpdate();
        }
 
        public void ReportCompletedTrial(TrialResult result)
        {
            MostRecentTrial = result;
            CompletedTrials.Add(result);
 
            var activeRunParam = JsonSerializer.Serialize(result.TrialSettings.Parameter, new JsonSerializerOptions() { WriteIndented = false, });
 
            TrialData.Append(new List<KeyValuePair<string, object>>()
            {
                new KeyValuePair<string, object>("Trial",result.TrialSettings.TrialId),
                new KeyValuePair<string, object>("Metric", result.Metric),
                new KeyValuePair<string, object>("Trainer",SweepablePipeline.ToString(result.TrialSettings.Parameter).Replace("Unknown=>","")),
                new KeyValuePair<string, object>("Parameters",activeRunParam),
            }, true);
 
            ThrottledUpdate();
        }
 
        public void ReportFailTrial(TrialSettings setting, Exception exp = null)
        {
            // TODO figure out what to do with failed trials.
            ThrottledUpdate();
        }
 
        public void ReportRunningTrial(TrialSettings setting)
        {
            ActiveTrial = setting;
            ThrottledUpdate();
        }
 
        private void ThrottledUpdate()
        {
            Task.Run(async () => await _updateThrottler.ExecuteAsync());
        }
 
        public void Update()
        {
            _valueToUpdate.Update(this);
        }
 
        public void SetUpdate(DisplayedValue valueToUpdate)
        {
            _valueToUpdate = valueToUpdate;
            ThrottledUpdate();
        }
    }
}