using System;
using System.Collections.Generic;
using System.IO;
using System.Net.Http;
using System.Text.Json;
using System.Threading.Tasks;
using Microsoft.Extensions.Logging;
using Props.Shop.Adafruit.Api;
using Props.Shop.Adafruit.Persistence;
using Props.Shop.Framework;

namespace Props.Shop.Adafruit
{
    public class AdafruitShop : IShop, IDisposable
    {
        private string workspaceDir;
        private ILoggerFactory loggerFactory;
        private ILogger<AdafruitShop> logger;
        private SearchManager searchManager;
        private Configuration configuration;
        private HttpClient http;
        private bool disposedValue;

        public string ShopName => "Adafruit";

        public string ShopDescription => "A electronic component online hardware company.";

        public string ShopModuleAuthor => "Reslate";

        public SupportedFeatures SupportedFeatures => new SupportedFeatures(
            false,
            false,
            false,
            false,
            true
        );
        public async ValueTask Initialize(string workspaceDir, ILoggerFactory loggerFactory)
        {
            workspaceDir = workspaceDir ?? "";
            this.workspaceDir = workspaceDir;
            this.loggerFactory = loggerFactory;
            logger = loggerFactory.CreateLogger<AdafruitShop>();
            http = new HttpClient();
            http.BaseAddress = new Uri("http://www.adafruit.com/api/");
            string configPath = Path.Combine(workspaceDir, Configuration.FILE_NAME);
            try
            {
                configuration = JsonSerializer.Deserialize<Configuration>(File.ReadAllText(configPath));
            }
            catch (JsonException e)
            {
                logger.LogWarning("Could not read JSON file \"{0}\": {1}", configPath, e.Message);
            }
            catch (ArgumentException)
            {
                logger.LogWarning("No working directory path provided.");
            }
            catch (DirectoryNotFoundException)
            {
                logger.LogWarning("Directory \"{0}\" could not be found.", Path.GetDirectoryName(configPath));
            }
            catch (FileNotFoundException)
            {
                logger.LogWarning("File \"{0}\" could not be found.", configPath);
            }
            finally
            {
                if (configuration == null)
                {
                    configuration = new Configuration();
                }
            }

            ProductListingCacheData listingData = null;
            string cachePath = Path.Combine(workspaceDir, ProductListingCacheData.FILE_NAME);
            try
            {
                using (Stream fileStream = File.OpenRead(cachePath))
                {
                    listingData = await JsonSerializer.DeserializeAsync<ProductListingCacheData>(fileStream);
                }
            }
            catch (JsonException e)
            {
                logger.LogWarning("Could not read JSON file \"{0}\": {1}", cachePath, e.Message);
            }
            catch (ArgumentException)
            {
                logger.LogWarning("No working directory path provided.");
            }
            catch (DirectoryNotFoundException)
            {
                logger.LogWarning("Directory \"{0}\" could not be found.", Path.GetDirectoryName(cachePath));
            }
            catch (FileNotFoundException)
            {
                logger.LogWarning("File \"{0}\" could not be found.", cachePath);
            }
            finally
            {
                if (configuration == null)
                {
                    configuration = new Configuration();
                }
            }
            LiveProductListingManager productListingManager = new LiveProductListingManager(http, loggerFactory.CreateLogger<LiveProductListingManager>(), listingData, configuration.MinDownloadInterval);
            this.searchManager = new SearchManager(productListingManager, configuration.Similarity);
            productListingManager.StartUpdateTimer(delay: 0, configuration.CacheLifespan);
        }

        public async Task<ProductListing> GetProductFromIdentifier(string identifier)
        {
            return await searchManager.ProductListingManager.GetProductListingFromIdentifier(identifier);
        }

        public IAsyncEnumerable<ProductListing> Search(string query, Filters filters)
        {
            return searchManager.Search(query);
        }

        public async ValueTask SaveData()
        {
            if (workspaceDir != null)
            {
                logger.LogDebug("Saving data in \"{0}\"...", workspaceDir);
                string configurationPath = Path.Combine(workspaceDir, Configuration.FILE_NAME);
                File.Delete(configurationPath);
                await File.WriteAllTextAsync(Path.Combine(workspaceDir, Configuration.FILE_NAME), JsonSerializer.Serialize(configuration));

                string productListingCachePath = Path.Combine(workspaceDir, ProductListingCacheData.FILE_NAME);
                File.Delete(productListingCachePath);
                using (Stream fileStream = File.OpenWrite(productListingCachePath))
                {
                    await JsonSerializer.SerializeAsync(fileStream, new ProductListingCacheData(await searchManager.ProductListingManager.ProductListings));
                }
                logger.LogDebug("Completed saving data.");
            }
        }

        public async ValueTask DisposeAsync()
        {
            Dispose(true);
            await DisposeAsyncCore();
        }

        protected virtual async ValueTask DisposeAsyncCore()
        {
            await SaveData();
        }

        protected virtual void Dispose(bool disposing)
        {
            if (!disposedValue)
            {
                if (disposing)
                {
                    http.Dispose();
                    searchManager.Dispose();
                }

                disposedValue = true;
            }
        }

        public void Dispose()
        {
            Dispose(disposing: true);
            GC.SuppressFinalize(this);
        }
    }
}