using System;
using System.Collections.Generic;
using System.Text;
using System.Linq;
using Windows.Devices.Enumeration;
using Windows.Security.Cryptography;
using Windows.Storage.Streams;
using System.Threading.Tasks;
using System.Threading;
using System.Text.RegularExpressions;
using BluetoothLENet.Classes;

namespace BluetoothLENet
{

    public static class Utilities
    {
        /// <summary>
        ///     Converts from standard 128bit UUID to the assigned 32bit UUIDs. Makes it easy to compare services
        ///     that devices expose to the standard list.
        /// </summary>
        /// <param name="uuid">UUID to convert to 32 bit</param>
        /// <returns></returns>
        public static ushort ConvertUuidToShortId(Guid uuid)
        {
            // Get the short Uuid
            var bytes = uuid.ToByteArray();
            var shortUuid = (ushort)(bytes[0] | bytes[1] << 8);
            return shortUuid;
        }

        /// <summary>
        ///     Converts from a buffer to a properly sized byte array
        /// </summary>
        /// <param name="buffer"></param>
        /// <returns></returns>
        public static byte[] ReadBufferToBytes(IBuffer buffer)
        {
            var dataLength = buffer.Length;
            var data = new byte[dataLength];
            using (var reader = DataReader.FromBuffer(buffer))
            {
                reader.ReadBytes(data);
            }
            return data;
        }

        /// <summary>
        /// This function converts IBuffer data to string by specified format
        /// </summary>
        /// <param name="buffer"></param>
        /// <param name="format"></param>
        /// <returns></returns>
        public static string FormatValue(IBuffer buffer, DataFormat format)
        {
            byte[] data;
            CryptographicBuffer.CopyToByteArray(buffer, out data);

            switch (format)
            {
                case DataFormat.ASCII:
                    return Encoding.ASCII.GetString(data);

                case DataFormat.UTF8:
                    return Encoding.UTF8.GetString(data);

                case DataFormat.Dec:
                    return string.Join(" ", data.Select(b => b.ToString("00")));

                case DataFormat.Hex:
                    return BitConverter.ToString(data).Replace("-", " ");

                case DataFormat.Bin:
                    var s = string.Empty;
                    foreach (var b in data) s += Convert.ToString(b, 2).PadLeft(8, '0') + " ";
                    return s;

                default:
                    return Encoding.ASCII.GetString(data);
            }
        }

        /// <summary>
        /// Format data for writing by specific format
        /// </summary>
        /// <param name="data"></param>
        /// <param name="format"></param>
        /// <returns></returns>
        public static IBuffer FormatData(string data, DataFormat format)
        {
            try
            {
                if (format == DataFormat.ASCII || format == DataFormat.UTF8)
                {
                    return CryptographicBuffer.ConvertStringToBinary(Regex.Unescape(data), BinaryStringEncoding.Utf8);
                }
                else
                {
                    string[] values = data.Split(new char[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);
                    byte[] bytes = new byte[values.Length];

                    for (int i = 0; i < values.Length; i++)
                        bytes[i] = Convert.ToByte(values[i], format == DataFormat.Dec ? 10 : format == DataFormat.Hex ? 16 : 2);

                    var writer = new DataWriter();
                    writer.ByteOrder = ByteOrder.LittleEndian;
                    writer.WriteBytes(bytes);

                    return writer.DetachBuffer();
                }
            }
            catch (Exception error)
            {
                Console.WriteLine(error.Message);
                return null;
            }
        }

        /// <summary>
        /// This function is trying to find device or service or attribute by name or number
        /// </summary>
        /// <param name="collection">source collection</param>
        /// <param name="name">name or number to find</param>
        /// <returns>ID for device, Name for services or attributes</returns>
        public static string GetIdByNameOrNumber(object collection, string name)
        {
            string result = string.Empty;

            // for devices
            if (collection is List<DeviceInformation>)
            {
                var foundDevices = (collection as List<DeviceInformation>).Where(d => d.Name.ToLower().StartsWith(name.ToLower())).ToList();
                if (foundDevices.Count == 0)
                {
                    if (!Console.IsOutputRedirected)
                        Console.WriteLine("Can't connect to {0}.", name);
                }
                else if (foundDevices.Count == 1)
                {
                    result = foundDevices.First().Id;
                }
                else
                {
                    if (!Console.IsOutputRedirected)
                        Console.WriteLine("Found multiple devices with names started from {0}. Please provide an exact name.", name);
                }
            }
            // for services or attributes
            else
            {
                var foundDispAttrs = (collection as List<BluetoothLEAttributeDisplay>).Where(d => d.Name.Split(':').Last().Trim().ToLower().StartsWith(name.ToLower())).ToList();
                if (foundDispAttrs.Count == 0)
                {
                    if (Console.IsOutputRedirected)
                        Console.WriteLine("No service/characteristic found by name {0}.", name);
                }
                else if (foundDispAttrs.Count == 1)
                {
                    result = foundDispAttrs.First().Name;
                }
                else
                {
                    if (Console.IsOutputRedirected)
                        Console.WriteLine("Found multiple services/characteristic with names started from {0}. Please provide an exact name.", name);
                }
            }
            return result;
        }
    }
}