using System.IO;
using System.Linq;
using System.Threading.Tasks;
using FarmmapsApi;
using FarmmapsApi.Models;
using FarmmapsApi.Services;
using FarmmapsHaulmkilling.Models;
using FarmmapsZonering.Models;
using FarmmapsZonering.Services;
using Microsoft.Extensions.Logging;
using Newtonsoft.Json;
using static FarmmapsApiSamples.Constants;

namespace FarmmapsZonering
{
    public class ZoneringApplication : IApplication
    {
        private const string DownloadFolder = "Downloads";
        private const string SettingsFile = "settings.json";

        private readonly ILogger<ZoneringApplication> _logger;
        private readonly FarmmapsApiService _farmmapsApiService;
        private readonly GeneralService _generalService;
        private readonly ZoneringService _zoneringService;

        private Settings _settings;
        
        public ZoneringApplication(ILogger<ZoneringApplication> logger, FarmmapsApiService farmmapsApiService,
            GeneralService generalService, ZoneringService zoneringService)
        {
            _logger = logger;
            _farmmapsApiService = farmmapsApiService;
            _generalService = generalService;
            _zoneringService = zoneringService;
        }
        
        public async Task RunAsync()
        {
            if (!Directory.Exists(DownloadFolder))
                Directory.CreateDirectory(DownloadFolder);

            LoadSettings();
            
            // !! 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();

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

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

            Item cropfieldItem;
            if (string.IsNullOrEmpty(_settings.CropfieldItemCode))
            {
                _logger.LogInformation("Creating cropfield");
                cropfieldItem = await _generalService.CreateCropfieldItemAsync(myDrive.Code, "Cropfield VRA Zonering", 2020, 
                    @"{ ""type"": ""Polygon"", ""coordinates"": [ [ [ 5.670991253771027, 52.796788997702613 ], [ 5.671526456638633, 52.797291618546666 ], [ 5.671275936147413, 52.797422436717852 ], [ 5.671959173850738, 52.798269302728798 ], [ 5.670649634919365, 52.798778791408822 ], [ 5.671503682048522, 52.799591206957416 ], [ 5.675159003761311, 52.798193567415474 ], [ 5.673029579585948, 52.796024727480535 ], [ 5.670991253771027, 52.796788997702613 ] ] ] }");
                _settings.CropfieldItemCode = cropfieldItem.Code;
                SaveSettings();
            }
            else
            {
                _logger.LogInformation("Cropfield already exists trying to get");
                cropfieldItem = await _farmmapsApiService.GetItemAsync(_settings.CropfieldItemCode);
            }

            var inputFileName = "neo_ndvi-reglone-low-weed.tif";
            var dataPath = Path.Combine("Data", inputFileName);
            var geotiffItem = await _generalService.UploadDataAsync(uploadedRoot, GEOTIFF_PROCESSED_ITEMTYPE, dataPath,
                Path.GetFileNameWithoutExtension(inputFileName));

            if (geotiffItem == null) {
                _logger.LogError("Could not find item for uploaded data");
                return;
            } 
            
            var outputItem = await _zoneringService.CreateApplicationMapAsync(cropfieldItem, "[0] * 2", new Output()
            {
                Name = "times_2_zonering",
                Unit = "n/kg",
                Quantity = "Nitrogen"
            }, new InputParameter()
            {
                ItemCode = geotiffItem.Code,
                ItemLayer = geotiffItem.Data["layers"][0]["name"].ToString()
            });
            
            _logger.LogInformation("Downloading output");
            await _farmmapsApiService.DownloadItemAsync(outputItem.Code,
                Path.Combine(DownloadFolder, $"times_2_zonering.zip"));
        }

        private void LoadSettings()
        {
            if (File.Exists(SettingsFile))
            {
                var jsonText = File.ReadAllText(SettingsFile);
                _settings = JsonConvert.DeserializeObject<Settings>(jsonText);
            }
            else
            {
                _settings = new Settings();
            }
        }

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

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