using MediaBrowser.Common.Configuration;
using MediaBrowser.Common.Extensions;
using MediaBrowser.Controller.Devices;
using MediaBrowser.Model.Devices;
using MediaBrowser.Model.Logging;
using MediaBrowser.Model.Serialization;
using MediaBrowser.Model.Session;
using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Threading.Tasks;

namespace MediaBrowser.Server.Implementations.Devices
{
    public class DeviceRepository : IDeviceRepository
    {
        private readonly object _syncLock = new object();

        private readonly IApplicationPaths _appPaths;
        private readonly IJsonSerializer _json;
        private ILogger _logger;

        private ConcurrentBag<DeviceInfo> _devices;

        public DeviceRepository(IApplicationPaths appPaths, IJsonSerializer json)
        {
            _appPaths = appPaths;
            _json = json;
        }

        private string GetDevicesPath()
        {
            return Path.Combine(_appPaths.DataPath, "devices");
        }

        private string GetDevicePath(string id)
        {
            return Path.Combine(GetDevicesPath(), id.GetMD5().ToString("N"));
        }

        public Task SaveDevice(DeviceInfo device)
        {
            var path = Path.Combine(GetDevicePath(device.Id), "device.json");
            Directory.CreateDirectory(Path.GetDirectoryName(path));

            lock (_syncLock)
            {
                _json.SerializeToFile(device, path);
                _devices = null;
            }
            return Task.FromResult(true);
        }

        public Task SaveCapabilities(string reportedId, ClientCapabilities capabilities)
        {
            var device = GetDevice(reportedId);
            device.Capabilities = capabilities;
            SaveDevice(device);

            return Task.FromResult(true);
        }

        public ClientCapabilities GetCapabilities(string reportedId)
        {
            var device = GetDevice(reportedId);

            return device == null ? null : device.Capabilities;
        }

        public DeviceInfo GetDevice(string id)
        {
            return GetDevices()
                .FirstOrDefault(i => string.Equals(i.Id, id, StringComparison.OrdinalIgnoreCase));
        }

        public IEnumerable<DeviceInfo> GetDevices()
        {
            if (_devices == null)
            {
                lock (_syncLock)
                {
                    if (_devices == null)
                    {
                        _devices = new ConcurrentBag<DeviceInfo>(LoadDevices());
                    }
                }
            }
            return _devices.ToList();
        }

        private IEnumerable<DeviceInfo> LoadDevices()
        {
            var path = GetDevicesPath();

            try
            {
                return new DirectoryInfo(path)
                    .EnumerateFiles("*", SearchOption.AllDirectories)
                    .Where(i => string.Equals(i.Name, "device.json", StringComparison.OrdinalIgnoreCase))
                    .Select(i =>
                    {
                        try
                        {
                            return _json.DeserializeFromFile<DeviceInfo>(i.FullName);
                        }
                        catch (Exception ex)
                        {
                            _logger.ErrorException("Error reading {0}", ex, i.FullName);
                            return null;
                        }
                    })
                    .Where(i => i != null)
                    .ToList();
            }
            catch (IOException)
            {
                return new List<DeviceInfo>();
            }
        }

        public Task DeleteDevice(string id)
        {
            var path = GetDevicePath(id);

            lock (_syncLock)
            {
                try
                {
                    Directory.Delete(path, true);
                }
                catch (DirectoryNotFoundException)
                {
                }

                _devices = null;
            }

            return Task.FromResult(true);
        }

        public ContentUploadHistory GetCameraUploadHistory(string deviceId)
        {
            var path = Path.Combine(GetDevicePath(deviceId), "camerauploads.json");

            lock (_syncLock)
            {
                try
                {
                    return _json.DeserializeFromFile<ContentUploadHistory>(path);
                }
                catch (IOException)
                {
                    return new ContentUploadHistory
                    {
                        DeviceId = deviceId
                    };
                }
            }
        }

        public void AddCameraUpload(string deviceId, LocalFileInfo file)
        {
            var path = Path.Combine(GetDevicePath(deviceId), "camerauploads.json");
            Directory.CreateDirectory(Path.GetDirectoryName(path));

            lock (_syncLock)
            {
                ContentUploadHistory history;

                try
                {
                    history = _json.DeserializeFromFile<ContentUploadHistory>(path);
                }
                catch (IOException)
                {
                    history = new ContentUploadHistory
                    {
                        DeviceId = deviceId
                    };
                }

                history.DeviceId = deviceId;
                history.FilesUploaded.Add(file);

                _json.SerializeToFile(history, path);
            }
        }
    }
}