using System;
using System.Linq;
using AsbCloudApp.Data;
using AsbCloudApp.Services;
using AsbCloudDb.Model;
using System.Collections.Generic;

namespace AsbCloudInfrastructure.Services
{
    public class AnalyticsService : IAnalyticsService
    {
        private readonly IAsbCloudDbContext db;
        private readonly ITelemetryService telemetryService;

        public AnalyticsService(IAsbCloudDbContext db, ITelemetryService telemetryService)
        {
            this.db = db;
            this.telemetryService = telemetryService;
        }

        public IEnumerable<WellDepthToDayDto> GetWellDepthToDayData(int wellId)
        {
            var telemetry = telemetryService.GetTelemetryByWellId(wellId);

            if (telemetry is null)
                return null;

            var depthToTimeData = (from d in db.DataSaubBases
                                   where d.IdTelemetry == telemetry.Id
                                   select new WellDepthToDayDto
                                   {
                                       WellDepth = d.WellDepth,
                                       BitDepth =d.BitDepth,
                                       Date = d.Date
                                   }).ToList();

            var m = (int)Math.Round(1d * depthToTimeData.Count / 2048);

            if (m > 1)
                depthToTimeData = depthToTimeData.Where((d, i) => i % m == 0).ToList();

            return depthToTimeData;
        }

        public IEnumerable<WellDepthToIntervalDto> GetWellDepthToIntervalData(int wellId, 
            double interval = 24.0, int beginHour = 8, int beginMinutes = 0)
        {
            var intervalHours = TimeSpan.FromHours(interval);
            var parseResult = TimeSpan.TryParse($"{beginHour}:{beginMinutes}", out var workDayBeginTime);

            if (!parseResult)
                workDayBeginTime = TimeSpan.FromHours(8);

            var telemetry = telemetryService.GetTelemetryByWellId(wellId);

            if (telemetry is null)
                return null;

            var drillingData = (from d in db.DataSaubBases
                                where d.IdTelemetry == telemetry.Id
                                select new
                                {
                                    d.WellDepth,
                                    d.Date
                                }).ToList();

            if (!drillingData.Any())
                return null;

            var drillingStartDate = drillingData.First().Date;
            var periodStart = drillingStartDate.Hour < 8
                ? new DateTime(drillingStartDate.Year, drillingStartDate.Month, drillingStartDate.Day).AddDays(-1) + workDayBeginTime
                : new DateTime(drillingStartDate.Year, drillingStartDate.Month, drillingStartDate.Day) + workDayBeginTime;

            var periodEnd = periodStart + intervalHours;
            var onePeriodData = new List<(double?, DateTime)>();
            var drillingPeriods = new List<IEnumerable<(double?, DateTime)>>();

            foreach (var d in drillingData)
            {
                if (d.Date < periodEnd)
                {
                    onePeriodData.Add((d.WellDepth, d.Date));
                    continue;
                }
                drillingPeriods.Add(onePeriodData);
                onePeriodData.Clear();
                periodStart = d.Date;
                periodEnd = periodStart + intervalHours;
                onePeriodData.Add((d.WellDepth, d.Date));
            }

            var wellDepthToIntervalData = drillingPeriods.Select(d => new WellDepthToIntervalDto
            {
                IntervalStartDate = d.FirstOrDefault().Item2,
                IntervalDepthProgress = (d.Last().Item1 - d.FirstOrDefault().Item1) ?? 0.0 / interval
            });

            return wellDepthToIntervalData;
        }
    }
}