using Mirle.Component.MPLC.DataBlocks.DeviceRange.Interfaces;
using System;
using System.Collections;
using System.Diagnostics;
using System.IO;
using System.IO.MemoryMappedFiles;

namespace Mirle.Component.MPLC.DataBlocks
{
    /// <summary>
    /// SM 資料區塊 (Int32)
    /// </summary>
    public class SMDataBlockInt32 : SMDataBlock
    {
        /// <summary>
        /// 建構式
        /// </summary>
        /// <param name="deviceRange">設備範圍介面</param>
        /// <param name="sharedMemoryName">共享記憶體名稱</param>
        public SMDataBlockInt32(ITypeDeviceRange deviceRange, string sharedMemoryName) : base(deviceRange, sharedMemoryName) { }
        /// <summary>
        /// 起始偏移量
        /// </summary>
        private readonly int _startOffset = 4;
        /// <summary>
        /// 初始化
        /// </summary>
        protected override void Initial()
        {
            _mmfLength = DeviceRange.ByteArrayLength;
            #if NET5_0 || NET6_0
            if (OperatingSystem.IsWindows())
            {
                _mmf = MemoryMappedFile.CreateOrOpen(_mmfName, _startOffset + (_mmfLength * 2));
            }
            else
            {
                _mmf = MemoryMappedFile.CreateFromFile(_mmfName);
            }
            #elif NETFRAMEWORK
            _mmf = MemoryMappedFile.CreateOrOpen(_mmfName, _startOffset + (_mmfLength * 2));
            #else
            _mmf = MemoryMappedFile.CreateFromFile(_mmfName);
            #endif
        }
        /// <summary>
        /// 設置原始資料
        /// </summary>
        /// <param name="newRawData">原始資料</param>
        public override void SetRawData(byte[] newRawData)
        {
            try
            {
                _rwLock.EnterWriteLock();
                MemoryMappedViewStream stream = _mmf.CreateViewStream();
                using BinaryWriter writer = new BinaryWriter(stream);
                stream.Seek(_startOffset, SeekOrigin.Begin);
                for (int i = 0; i < Math.Min(newRawData.Length, _mmfLength); i += 2)
                {
                    writer.Write(newRawData[i]);
                    writer.Write(newRawData[i + 1]);
                    stream.Seek(2, SeekOrigin.Current);
                }
            }
            finally
            {
                _rwLock.ExitWriteLock();
            }
        }
        /// <summary>
        /// 取得原始資料
        /// </summary>
        /// <returns>原始資料</returns>
        public override byte[] GetRawData()
        {
            byte[] data = new byte[_mmfLength];
            try
            {
                _rwLock.EnterReadLock();
                MemoryMappedViewStream stream = _mmf.CreateViewStream();
                using BinaryReader reader = new BinaryReader(stream);
                stream.Seek(_startOffset, SeekOrigin.Begin);
                for (int i = 0; i < _mmfLength; i += 2)
                {
                    data[i] = reader.ReadByte();
                    data[i + 1] = reader.ReadByte();
                    stream.Seek(2, SeekOrigin.Current);
                }
            }
            finally
            {
                _rwLock.ExitReadLock();
            }
            return data;
        }
        /// <summary>
        /// 取得位元
        /// </summary>
        /// <param name="address">位置</param>
        /// <param name="value">是否成功取得</param>
        /// <returns>True/False</returns>
        public override bool TryGetBit(string address, out bool value)
        {
            value = false;
            try
            {
                _rwLock.EnterReadLock();
                if (DeviceRange.TryGetByteArrayOffset(address, out int offset) && DeviceRange.TryGetByteArrayBitIndex(address, out int index))
                {
                    MemoryMappedViewStream stream = _mmf.CreateViewStream();
                    using BinaryReader reader = new BinaryReader(stream);
                    stream.Seek(_startOffset + offset * 2, SeekOrigin.Begin);
                    ushort word = reader.ReadUInt16();
                    BitArray bitArray = new BitArray(BitConverter.GetBytes(word));
                    value = bitArray.Get(index);
                    return true;
                }
            }
            catch (Exception ex)
            {
                Debug.WriteLine($"{ex.Message}-{ex.StackTrace}");
            }
            finally
            {
                _rwLock.ExitReadLock();
            }
            return false;
        }
        /// <summary>
        /// 設置位元
        /// </summary>
        /// <param name="address">位置</param>
        /// <param name="IsOn">是否開啟</param>
        /// <returns>True/False</returns>
        protected override bool SetBit(string address, bool IsOn)
        {
            try
            {
                _rwLock.EnterWriteLock();
                if (DeviceRange.TryGetByteArrayOffset(address, out int offset) && DeviceRange.TryGetByteArrayBitIndex(address, out int index))
                {
                    int startOffset = _startOffset + offset * 2;
                    MemoryMappedViewStream stream = _mmf.CreateViewStream();

                    using BinaryReader reader = new BinaryReader(stream);
                    stream.Seek(startOffset, SeekOrigin.Begin);
                    ushort word = reader.ReadUInt16();
                    BitArray bitArray = new BitArray(BitConverter.GetBytes(word));
                    bitArray.Set(index, IsOn);
                    byte[] tmpBytes = new byte[2];
                    bitArray.CopyTo(tmpBytes, 0);
                    stream = _mmf.CreateViewStream();

                    using BinaryWriter writer = new BinaryWriter(stream);
                    stream.Seek(startOffset, SeekOrigin.Begin);
                    writer.Write(tmpBytes[0]);
                    writer.Write(tmpBytes[1]);
                    return true;
                }
            }
            catch (Exception ex)
            {
                Debug.WriteLine($"{ex.Message}-{ex.StackTrace}"); 
            }
            finally
            {
                _rwLock.ExitWriteLock();
            }
            return false;
        }
        /// <summary>
        /// 取得字元
        /// </summary>
        /// <param name="address">位置</param>
        /// <param name="value">值</param>
        /// <returns>True/False</returns>
        public override bool TryGetWord(string address, out int value)
        {
            value = 0;
            try
            {
                _rwLock.EnterReadLock();
                if (DeviceRange.TryGetByteArrayOffset(address, out int offset))
                {
                    MemoryMappedViewStream stream = _mmf.CreateViewStream();
                    using BinaryReader reader = new BinaryReader(stream);
                    stream.Seek(_startOffset + offset * 2, SeekOrigin.Begin);
                    value = reader.ReadUInt16();
                    return true;
                }
            }
            catch (Exception ex)
            {
                Debug.WriteLine($"{ex.Message}-{ex.StackTrace}"); 
            }
            finally
            {
                _rwLock.ExitReadLock();
            }
            return false;
        }
        /// <summary>
        /// 設置字元
        /// </summary>
        /// <param name="address">位置</param>
        /// <param name="value">值</param>
        /// <returns>True/False</returns>
        public override bool TrySetWord(string address, int value)
        {
            try
            {
                _rwLock.EnterWriteLock();
                if (DeviceRange.TryGetByteArrayOffset(address, out int offset))
                {
                    MemoryMappedViewStream stream = _mmf.CreateViewStream();
                    using var writer = new BinaryWriter(stream);
                    stream.Seek(_startOffset + offset * 2, SeekOrigin.Begin);
                    byte[] tmpBytes = BitConverter.GetBytes(value);
                    writer.Write(tmpBytes[0]);
                    writer.Write(tmpBytes[1]);
                    return true;
                }
            }
            catch (Exception ex)
            { 
                Debug.WriteLine($"{ex.Message}-{ex.StackTrace}"); 
            }
            finally
            {
                _rwLock.ExitWriteLock();
            }
            return false;
        }
        /// <summary>
        /// 取得多個字元
        /// </summary>
        /// <param name="address">位置</param>
        /// <param name="data">資料及</param>
        /// <param name="length">長度</param>
        /// <returns>True/False</returns>
        public override bool TryGetWords(string address, out int[] data, int length)
        {
            data = new int[length];
            try
            {
                _rwLock.EnterReadLock();
                if (DeviceRange.TryGetByteArrayOffset(address, out int offset))
                {
                    MemoryMappedViewStream stream = _mmf.CreateViewStream();
                    using BinaryReader reader = new BinaryReader(stream);
                    stream.Seek(_startOffset + offset * 2, SeekOrigin.Begin);
                    for (int i = 0; i < length; i++)
                    {
                        data[i] = reader.ReadUInt16();
                        stream.Seek(2, SeekOrigin.Current);
                    }
                    return true;
                }
            }
            catch (Exception ex)
            {
                Debug.WriteLine($"{ex.Message}-{ex.StackTrace}"); 
            }
            finally
            {
                _rwLock.ExitReadLock();
            }
            return false;
        }
        /// <summary>
        /// 設置多個字元
        /// </summary>
        /// <param name="address">位置</param>
        /// <param name="data">資料集</param>
        /// <returns>True/False</returns>
        public override bool TrySetWords(string address, int[] data)
        {
            try
            {
                _rwLock.EnterWriteLock();
                if (DeviceRange.TryGetByteArrayOffset(address, out int offset))
                {
                    MemoryMappedViewStream stream = _mmf.CreateViewStream();
                    using BinaryWriter writer = new BinaryWriter(stream);
                    stream.Seek(_startOffset + offset * 2, SeekOrigin.Begin);
                    for (int i = 0; i < data.Length; i++)
                    {
                        byte[] tmpBytes = BitConverter.GetBytes(data[i]);
                        writer.Write(tmpBytes[0]);
                        writer.Write(tmpBytes[1]);
                        stream.Seek(2, SeekOrigin.Current);
                    }
                    return true;
                }
            }
            catch (Exception ex)
            {
                Debug.WriteLine($"{ex.Message}-{ex.StackTrace}");
            }
            finally
            {
                _rwLock.ExitWriteLock();
            }
            return false;
        }
    }
}