using System;
using System.Collections.Generic;
using System.IO;
using System.IO.Compression;
using System.Linq;
using System.Threading.Tasks;
using FarmmapsApi;
using FarmmapsApi.Models;
using FarmmapsApi.Services;
using FarmmapsKPI.Models;
using Microsoft.Extensions.Logging;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;
using static FarmmapsApiSamples.Constants;

namespace FarmmapsKPI
{
    public class KPIApplication : IApplication
    {
        //private const string DownloadFolder = "Downloads";
        private const string SettingsFile = "settings.json";

        private readonly ILogger<KPIApplication> _logger;
        private readonly FarmmapsApiService _farmmapsApiService;
        private readonly KPIService _kpiService;
        private readonly GeneralService _generalService;

        private Settings _settings;

        public KPIApplication(ILogger<KPIApplication> logger, FarmmapsApiService farmmapsApiService,
            GeneralService generalService, KPIService kpiService)
        {
            _logger = logger;
            _farmmapsApiService = farmmapsApiService;
            _generalService = generalService;
            _kpiService = kpiService;
        }

        public async Task RunAsync()
        {
            var fieldsInputJson = File.ReadAllText("KPIInput.json");

            List<KPIInput> fieldsInputs = JsonConvert.DeserializeObject<List<KPIInput>>(fieldsInputJson);

            // !! this call is needed the first time an api is called with a fresh clientid and secret !!
            await _farmmapsApiService.GetCurrentUserCodeAsync();
            var roots = await _farmmapsApiService.GetCurrentUserRootsAsync();

            foreach (var input in fieldsInputs)
            {
                try
                {
                    await Process(roots, input);
                }
                catch (Exception ex)
                {
                    _logger.LogError(ex.Message);
                }
            }
        }

        private async Task Process(List<UserRoot> roots, KPIInput input)
        {
            string downloadFolder = input.DownloadFolder;
            if (string.IsNullOrEmpty(downloadFolder)) {
                downloadFolder = "Downloads";
            }
            if (!Directory.Exists(downloadFolder))
                Directory.CreateDirectory(downloadFolder);

            // !!specify if you are using an already created cropfield:
            bool useCreatedCropfield = input.UseCreatedCropfield;
            bool useCreatedCropRecording = input.UseCreatedCropRecording;
            bool useCreatedOperations = input.UseCreatedOperation;
            bool useCreatedCropfieldCharacteristic = input.UseCreatedCropfieldCharacteristic;
            var cropYear = input.CropYear;
            var fieldName = input.fieldName;
            //bool storeSatelliteStatistics = input.StoreSatelliteStatisticsSingleImage;
            //bool storeSatelliteStatisticsCropYear = input.StoreSatelliteStatisticsCropYear;
            //List<string> SatelliteBands = new List<string>(1) { input.SatelliteBand };
            //string headerLineStats = $"FieldName,satelliteDate,satelliteBand,max,min,mean,mode,median,stddev,minPlus,curtosis,maxMinus,skewness,variance,populationCount,variationCoefficient,confidenceIntervalLow, confidenceIntervalHigh,confidenceIntervalErrorMargin" + Environment.NewLine;


            string settingsfile = $"Settings_{fieldName}.json";

            LoadSettings(settingsfile);

            var uploadedRoot = roots.SingleOrDefault(r => r.Name == "USER_IN");
            if (uploadedRoot == null)
            {
                _logger.LogError("Could not find a needed root item");
                return;
            }

            var myDriveRoot = roots.SingleOrDefault(r => r.Name == "USER_FILES");
            if (myDriveRoot == null)
            {
                _logger.LogError("Could not find a needed root item");
                return;
            }

            // Use already created cropfield or create new one, added a Data input, with field specific data for the KPI calculation
            Item cropfieldItem;
            //1 useCreatedCropfield = false -> create new
            //2 useCreatedCropfield = true && CropfieldItemCode = "" or absent -> read from settings json
            //3 useCreatedCropfield = true && CropfieldItemCode like "deb48a74c5b54299bb852f17288010e9" in KPIinput -> use this one
            if (useCreatedCropfield == false || string.IsNullOrEmpty(_settings.CropfieldItemCode))
            {
                _logger.LogInformation("Creating cropfield, writting to settings file");
                cropfieldItem = await _generalService.CreateCropfieldItemAsync(myDriveRoot.Code,
                    $"{input.OutputFileName}", cropYear, input.GeometryJson.ToString(Formatting.None), input.DataCropfield.ToString(Formatting.None));
                _settings.CropfieldItemCode = cropfieldItem.Code;
                SaveSettings(settingsfile);
            }
            else if (string.IsNullOrEmpty(input.CropfieldItemCode))
            {
                _logger.LogInformation("reading CropfieldItemCode from settings file");
                cropfieldItem = await _farmmapsApiService.GetItemAsync(_settings.CropfieldItemCode);
            }
            else
            {
                _logger.LogInformation("reading CropfieldItemCode from KPIinput.json");
                cropfieldItem = await _farmmapsApiService.GetItemAsync(input.CropfieldItemCode);
            }


            // Use already created croprecording or create new one, added a Data input, with field specific data for the KPI calculation
            Item crprecItem;
            //1 useCreatedCropRecording = false -> create new
            //2 useCreatedCropRecording = true && CropRecordingItemCode = "" or absent -> read from settings json
            //3 useCreatedCropRecording = true && CropRecordingItemCode like "deb48a74c5b54299bb852f17288010e9" in KPIinput -> use this one
            if (useCreatedCropRecording == false || string.IsNullOrEmpty(_settings.CropRecordingItemCode))
            {
                _logger.LogInformation("RunCropRecordingTask ...");
                crprecItem = await _generalService.RunCropRecordingTask(cropfieldItem);
                _settings.CropRecordingItemCode = crprecItem.Code;
                SaveSettings(settingsfile);
            }
            else if (string.IsNullOrEmpty(input.CropfieldItemCode))
            {
                _logger.LogInformation("reading CropRecordingItemCode from settings file");
                crprecItem = await _farmmapsApiService.GetItemAsync(_settings.CropRecordingItemCode);
            }
            else
            {
                _logger.LogInformation("reading CropRecordingItemCode from KPIinput.json");
                crprecItem = await _farmmapsApiService.GetItemAsync(input.CropRecordingItemCode);
            }

            // Use already created operation or create new one, added a Data input, with field specific data for the KPI calculation
            Item crpOperationItem;
            //1 useCreatedOperation = false -> create new
            //2 useCreatedOperation = true && OperationItemCode = "" or absent -> read from settings json
            //3 useCreatedOperation = true && OperationItemCode like "deb48a74c5b54299bb852f17288010e9" in KPIinput -> use this one
            if (useCreatedOperations == false || string.IsNullOrEmpty(_settings.OperationItemCode))
            {
                _logger.LogInformation("CreateOperationItemAsync ...");
                crpOperationItem = await _generalService.CreateOperationItemAsync(crprecItem.Code, cropYear, input.GeometryJson.ToString(Formatting.None), input.DataOperation.ToString(Formatting.None));
                _settings.OperationItemCode = crpOperationItem.Code;
                SaveSettings(settingsfile);
            }
            else if (string.IsNullOrEmpty(input.CropfieldItemCode))
            {
                _logger.LogInformation("reading OperationItemCode from settings file");
                crpOperationItem = await _farmmapsApiService.GetItemAsync(_settings.OperationItemCode);
            }
            else
            {
                _logger.LogInformation("reading OperationItemCode from KPIinput.json");
                crpOperationItem = await _farmmapsApiService.GetItemAsync(input.OperationItemCode);
            }

            // The cropfieldCharacteristicItem is used to enter crop yields
            // So once we have added an operation for fertilizer application and a crop yield, then KPIapp can calculate
            // Nutrient balance.
            // Use already created cropfieldCharacteristicItem or create new one, added a Data input, with field specific data for the KPI calculation
            Item cropfieldCharacteristicItem;
            //1 useCreatedCropfieldCharacteristic = false -> create new
            //2 useCreatedCropfieldCharacteristic = true && CropfieldCharacteristicItemCode = "" or absent -> read from settings json
            //3 useCreatedCropfieldCharacteristic = true && CropfieldCharacteristicItemCode like "deb48a74c5b54299bb852f17288010e9" in KPIinput -> use this one
            if (useCreatedCropfieldCharacteristic == false)
            {
                _logger.LogInformation("CreateCropfieldCharacteristicItemAsync ...");
                cropfieldCharacteristicItem = await _generalService.CreateCropfieldCharacteristicItemAsync(cropfieldItem.Code, cropYear, input.GeometryJson.ToString(Formatting.None), input.DataCropfieldCharacteristic.ToString(Formatting.None));
                _settings.CropfieldCharacteristicItemCode = cropfieldCharacteristicItem.Code;
                SaveSettings(settingsfile);
            }
            else if (string.IsNullOrEmpty(input.CropfieldCharacteristicItemCode))
            {
                _logger.LogInformation("reading OperationItemCode from settings file");
                cropfieldCharacteristicItem = await _farmmapsApiService.GetItemAsync(_settings.CropfieldCharacteristicItemCode);
            }
            else
            {
                _logger.LogInformation("reading CropfieldCharacteristicItemCode from KPIinput.json");
                cropfieldCharacteristicItem = await _farmmapsApiService.GetItemAsync(input.CropfieldCharacteristicItemCode);
            }

            // Inspect the children. If all is well, cropfield will have one crprec and one edicrop.characteristic
            // And the crprec will have 0-many operations as children
            // And the Data of an operation will have specification of how much fertilizer was applied
            // And crprec can have multiple operations
            // Note existing cropfields and croprecordings keep existing properties you added in previous runs
            // (unless you deleted them)
            // So ech time you run with "UseCreatedCropfield": true & "UseCreatedCropRecording": false -> a new recording will be added to the existing cropfield
            // So ech time you run with "UseCreatedCropfield": true & "useCreatedCropfieldCharacteristic": false -> a new CropfieldCharacteristic will be added to the existing cropfield
            // So ech time you run with "UseCreatedCropRecording": true & "UseCreatedOperation": false -> a new operation will be added to the existing crop recording
            var cropfieldChildren = await _farmmapsApiService.GetItemChildrenAsync(cropfieldItem.Code);
            var crprecChildren = await _farmmapsApiService.GetItemChildrenAsync(crprecItem.Code);

            //Now get the KPIs for this cropfield, mounted with operations & cropyield
            // Get KPI data for saving it in a file, here the generalsedrvice is called to get the KPI data
            _logger.LogInformation($"GetKpiItemsForCropField('{cropfieldItem.Code}')");
            var KPIItem = await _generalService.GetKpiItemsForCropField(cropfieldItem);

            //Download KPI's into a json output file for this specific cropfield (with unique cropfieldItem.Code)
            var KPIItemPath = Path.Combine(downloadFolder, $"KPIItems_{cropfieldItem.Code}.json");
            _logger.LogInformation($"Found {KPIItem.Count} KPI items");
            var count = 0;
            await Task.Delay(50);
            foreach (var item in KPIItem)
            {
                Console.WriteLine($"KPI item #{count}: {item.Name}");
                File.AppendAllText(KPIItemPath, item.Data + Environment.NewLine);
                count++;
            }
            _logger.LogInformation($"Downloaded file {KPIItemPath}");

        }

        // Functions to save previously created cropfields
        private void LoadSettings(string file)
        {
            if (File.Exists(file))
            {
                var jsonText = File.ReadAllText(file);
                _settings = JsonConvert.DeserializeObject<Settings>(jsonText);
            }
            else
            {
                _settings = new Settings();
            }
        }

        private void SaveSettings(string file)
        {
            if (_settings == null)
                return;

            var json = JsonConvert.SerializeObject(_settings);
            File.WriteAllText(file, json);
        }
        private void SaveInfo(string file)
        {
            if (_settings == null)
                return;

            var json = JsonConvert.SerializeObject(_settings);
            File.WriteAllText(file, json);

        }

    }
}