using AsbCloudDb.Model;
using System;
using System.Collections.Generic;
using System.Linq;

namespace AsbCloudInfrastructure.Services.DetectOperations.Detectors
{
    class OperationDetectorResult
    {
        public int TelemetryBegin { get; set; }
        public int TelemetryEnd { get; set; }
        public DetectedOperation Operation { get; set; }
    }

    internal class OperationDetector : IOperationDetector
    {
        private readonly int idOperation;

        protected Func<DetectableTelemetry[], int, int, bool> isValid = (_,_,_) => true;

        protected Func<DetectableTelemetry[], int, int, double> calcValue = (_, _, _) => 0d;

        public OperationDetector(int idOperation)
        {
            this.idOperation = idOperation;
        }

        public bool TryDetect(int idTelemetry, DetectableTelemetry[] telemetryFragment, int begin, int end, out IEnumerable<OperationDetectorResult> operations)
        {
            if(!telemetryFragment.Any() || !isValid(telemetryFragment, begin, end))
            {
                operations = Enumerable.Empty<OperationDetectorResult>();
                return false;
            }

            var operation = MakeOperation(idTelemetry, telemetryFragment, begin, end);

            operations = new List<OperationDetectorResult> { operation };

            return true;
        }

        private OperationDetectorResult MakeOperation(int idTelemetry, DetectableTelemetry[] telemetryFragment, int begin, int end)
        {
            var pBegin = telemetryFragment[begin];
            var pEnd = telemetryFragment[end];
            var result = new OperationDetectorResult
            {
                TelemetryBegin = begin,
                TelemetryEnd = end,
                Operation = new DetectedOperation
                {
                    IdTelemetry = idTelemetry,
                    IdCategory = idOperation,
                    IdUsersAtStart = pBegin.IdUser ?? -1,
                    DateStart = pBegin.DateTime,
                    DateEnd = pEnd.DateTime,
                    DepthStart = (double)pBegin.WellDepth,
                    DepthEnd = (double)pEnd.WellDepth,
                    Value = calcValue(telemetryFragment, begin, end),
                },
            };
            return result;
        }
    }
}