using System;
using System.Collections.Generic;
using System.Globalization;
using Sony.ChartBot.Entities.ChartApi;
using Sony.ChartBot.Entities.Storage;

namespace Sony.ChartBot.Messages.Helpers
{
    public class ChartPositionOutputBuilder
    {
        public string GetChartPositionsOutput(IEnumerable<ChartPosition> positions, SupportedCountry country)
        {
            var chartPositionText = string.Empty;

            foreach (var position in positions)
            {
                chartPositionText += GetChartPositionText(country, position) + "\r\n";
            }

            return chartPositionText;
        }

        public string GetChartPositionText(SupportedCountry country, ChartPosition position)
        {
            int? change = null;

            if (position.PreviousPosition.HasValue)
            {
                change = position.PreviousPosition.Value - position.Position;
            }

            var changeEmoji = GetChangeEmoji(change);

            var chartPositionText =
                $"{country.Emoji} {position.ChartType} #{position.Position} ({position.PreviousPosition?.ToString() ?? "-"}) {changeEmoji} {(change >= 0 ? "+" + change : change.ToString())}";

            return chartPositionText;
        }

        private string GetChangeEmoji(int? change)
        {
            string changeEmoji;

            if (change == null)
            {
                changeEmoji = "🆕";
            }
            else if (change.Value == 0)
            {
                changeEmoji = "➡️";
            }
            else if (change.Value > 0)
            {
                changeEmoji = "⬆️";
            }
            else
            {
                changeEmoji = "⬇️";
            }
            return changeEmoji;
        }

        public string GetChartPositionComparisonText(SupportedCountry country, ChartPosition position)
        {
            int? change = null;

            if (position.PreviousPosition.HasValue)
            {
                change = position.PreviousPosition.Value - position.Position;
            }

            var changeEmoji = GetChangeEmoji(change);

            var chartPositionText =
                $"{country.Emoji} #{position.Position} ({position.PreviousPosition?.ToString() ?? "-"}) {changeEmoji} {(change >= 0 ? "+" + change : change.ToString())}";

            return chartPositionText;
        }

        public string GetChartTimestampsOutput(IEnumerable<Chart> chartSource)
        {
            var chartTimestamps = new List<string>();

            foreach (var chart in chartSource)
            {
                var timestampTextFormat = chart.Updated.Date == DateTime.Today ? "h:mm tt" : "MMM d h:mm tt";
                var timestampText = chart.Updated.Date.ToString(timestampTextFormat, CultureInfo.GetCultureInfo("en-US"));
                chartTimestamps.Add($"{timestampText} {chart.ChartType}");
            }

            // TODO: Temp to test output
            chartTimestamps.Add("1:00 AM iTunes");
            chartTimestamps.Add("2:00 AM YouTube");

            var chartSourcesTimestampsText = "⌚ " + string.Join(", ", chartTimestamps);

            return chartSourcesTimestampsText;
        }
    }
}