//******************************************************************************************************//  FrameParser.cs - Gbtc////  Copyright © 2012, Grid Protection Alliance.  All Rights Reserved.////  Licensed to the Grid Protection Alliance (GPA) under one or more contributor license agreements. See//  the NOTICE file distributed with this work for additional information regarding copyright ownership.//  The GPA licenses this file to you under the MIT License (MIT), the "License"; you may//  not use this file except in compliance with the License. You may obtain a copy of the License at:////      http://www.opensource.org/licenses/MIT////  Unless agreed to in writing, the subject software distributed under the License is distributed on an//  "AS-IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. Refer to the//  License for the specific language governing permissions and limitations.////  Code Modification History://  ----------------------------------------------------------------------------------------------------//  01/14/2005 - J. Ritchie Carroll//       Generated original version of source code.//  09/15/2009 - Stephen C. Wills//       Added new header and license agreement.//  05/19/2011 - Ritchie//       Added DST file support.//  12/17/2012 - Starlynn Danyelle Gilliam//       Modified Header.////****************************************************************************************************** using System;using System.IO;using System.Security.Permissions;using System.Text;using GSF.IO;using GSF.Parsing; namespace GSF.PhasorProtocols.BPAPDCstream{    /// <summary>    /// Represents a frame parser for a BPA PDCstream binary data stream and returns parsed data via events.    /// </summary>    /// <remarks>    /// Frame parser is implemented as a write-only stream - this way data can come from any source.    /// </remarks>    [PermissionSet(SecurityAction.Demand, Name = "FullTrust")] // Required by file watcher...    public class FrameParser : FrameParserBase<FrameType>    {        #region [ Members ]         // Events         /// <summary>        /// Occurs when a BPA PDCstream <see cref="ConfigurationFrame"/> has been received.        /// </summary>        /// <remarks>        /// <see cref="EventArgs{T}.Argument"/> is the <see cref="ConfigurationFrame"/> that was received.        /// </remarks>        public new event EventHandler<EventArgs<ConfigurationFrame>> ReceivedConfigurationFrame;         /// <summary>        /// Occurs when a BPA PDCstream <see cref="DataFrame"/> has been received.        /// </summary>        /// <remarks>        /// <see cref="EventArgs{T}.Argument"/> is the <see cref="DataFrame"/> that was received.        /// </remarks>        public new event EventHandler<EventArgs<DataFrame>> ReceivedDataFrame;         // Fields        private ConfigurationFrame m_configurationFrame;        private string m_configurationFileName;        private bool m_refreshConfigurationFileOnChange;        private SafeFileWatcher m_configurationFileWatcher;        private readonly object m_syncLock;        private bool m_disposed;         #endregion         #region [ Constructors ]         /// <summary>        /// Creates a new <see cref="FrameParser"/>.        /// </summary>        /// <param name="checkSumValidationFrameTypes">Frame types that should perform check-sum validation; default to <see cref="CheckSumValidationFrameTypes.AllFrames"/></param>        /// <param name="trustHeaderLength">Determines if header lengths should be trusted over parsed byte count.</param>        /// <param name="configurationFileName">The required external BPA PDCstream INI based configuration file.</param>        public FrameParser(CheckSumValidationFrameTypes checkSumValidationFrameTypes = CheckSumValidationFrameTypes.AllFrames, bool trustHeaderLength = true, string configurationFileName = null)            : base(checkSumValidationFrameTypes, trustHeaderLength)        {            // Initialize protocol synchronization bytes for this frame parser            base.ProtocolSyncBytes = new[] { PhasorProtocols.Common.SyncByte };            m_syncLock = new object();            m_configurationFileName = configurationFileName;        }         #endregion         #region [ Properties ]         /// <summary>        /// Gets or sets current <see cref="IConfigurationFrame"/> used for parsing <see cref="IDataFrame"/>'s encountered in the data stream from a device.        /// </summary>        /// <remarks>        /// If a <see cref="IConfigurationFrame"/> has been parsed, this will return a reference to the parsed frame.  Consumer can manually assign a        /// <see cref="IConfigurationFrame"/> to start parsing data if one has not been encountered in the stream.        /// </remarks>        public override IConfigurationFrame ConfigurationFrame        {            get => m_configurationFrame;            set => m_configurationFrame = CastToDerivedConfigurationFrame(value, m_configurationFileName);        }         /// <summary>        /// Gets flag that determines if this protocol parsing implementation uses synchronization bytes.        /// </summary>        public override bool ProtocolUsesSyncBytes => !UsePhasorDataFileFormat;         /// <summary>        /// Gets or sets required external BPA PDCstream INI based configuration file.        /// </summary>        public string ConfigurationFileName        {            get => m_configurationFrame?.ConfigurationFileName ?? m_configurationFileName;            set            {                m_configurationFileName = value;                ResetFileWatcher();            }        }         /// <summary>        /// Gets or sets flag that determines if configuration file is automatically reloaded when it has changed on disk.        /// </summary>        public bool RefreshConfigurationFileOnChange        {            get => m_refreshConfigurationFileOnChange;            set            {                m_refreshConfigurationFileOnChange = value;                ResetFileWatcher();            }        }         /// <summary>        /// Gets or sets flag that interprets word count in packet header from a byte instead of a word.        /// </summary>        /// <remarks>        /// Set to <c>true</c> to interpret word count in packet header from a byte instead of a word - if the sync byte        /// (0xAA) is at position one, then the word count would be interpreted from byte four.  Some older BPA PDC        /// stream implementations have a 0x01 in byte three where there should be a 0x00 and this throws off the        /// frame length, setting this property to <c>true</c> will correctly interpret the word count.        /// </remarks>        public bool ParseWordCountFromByte { get; set; }         /// <summary>        /// Gets or sets flag that determines if source data is in the Phasor Data File Format (i.e., a DST file).        /// </summary>        public bool UsePhasorDataFileFormat { get; set; }         /// <summary>        /// Gets current descriptive status of the <see cref="FrameParser"/>.        /// </summary>        public override string Status        {            get            {                StringBuilder status = new();                 status.Append("    INI configuration file: ");                status.Append(FilePath.TrimFileName(m_configurationFileName, 51));                status.AppendLine();                status.Append("  Using phasor file format: ");                status.Append(UsePhasorDataFileFormat);                status.AppendLine();                 if (m_configurationFrame is not null)                {                    status.Append("       BPA PDC stream type: ");                    status.Append(m_configurationFrame.StreamType);                    status.AppendLine();                    status.Append("   BPA PDC revision number: ");                    status.Append(m_configurationFrame.RevisionNumber);                    status.AppendLine();                }                 status.Append(" Auto-reload configuration: ");                status.Append(m_refreshConfigurationFileOnChange);                status.AppendLine();                status.Append("Parse word count from byte: ");                status.Append(ParseWordCountFromByte);                status.AppendLine();                                status.Append(base.Status);                 return status.ToString();            }        }         /// <summary>        /// Gets or sets any connection specific <see cref="IConnectionParameters"/> that may be needed for parsing.        /// </summary>        public override IConnectionParameters ConnectionParameters        {            get => base.ConnectionParameters;            set            {                if (value is not ConnectionParameters parameters)                    return;                 base.ConnectionParameters = parameters;                 // Assign new incoming connection parameter values                m_configurationFileName = parameters.ConfigurationFileName;                ParseWordCountFromByte = parameters.ParseWordCountFromByte;                m_refreshConfigurationFileOnChange = parameters.RefreshConfigurationFileOnChange;                UsePhasorDataFileFormat = parameters.UsePhasorDataFileFormat;                ResetFileWatcher();            }        }         #endregion         #region [ Methods ]         /// <summary>        /// Releases the unmanaged resources used by the <see cref="FrameParser"/> object and optionally releases the managed resources.        /// </summary>        /// <param name="disposing">true to release both managed and unmanaged resources; false to release only unmanaged resources.</param>        protected override void Dispose(bool disposing)        {            if (m_disposed)                return;             try            {                if (!disposing)                    return;                 if (m_configurationFileWatcher is not null)                {                    m_configurationFileWatcher.Changed -= m_configurationFileWatcher_Changed;                    m_configurationFileWatcher.Dispose();                }                 m_configurationFileWatcher = null;            }            finally            {                m_disposed = true;       // Prevent duplicate dispose.                base.Dispose(disposing); // Call base class Dispose().            }        }         /// <summary>        /// Start the data parser.        /// </summary>        public override void Start()        {            // We narrow down parsing types to just those needed...            base.Start(new[] { typeof(DataFrame), typeof(ConfigurationFrame) });        }         /// <summary>        /// Parses a common header instance that implements <see cref="ICommonHeader{TTypeIdentifier}"/> for the output type represented        /// in the binary image.        /// </summary>        /// <param name="buffer">Buffer containing data to parse.</param>        /// <param name="offset">Offset index into buffer that represents where to start parsing.</param>        /// <param name="length">Maximum length of valid data from offset.</param>        /// <returns>The <see cref="ICommonHeader{TTypeIdentifier}"/> which includes a type ID for the <see cref="Type"/> to be parsed.</returns>        /// <remarks>        /// <para>        /// Derived classes need to provide a common header instance (i.e., class that implements <see cref="ICommonHeader{TTypeIdentifier}"/>)        /// for the output types; this will primarily include an ID of the <see cref="Type"/> that the data image represents.  This parsing is        /// only for common header information, actual parsing will be handled by output type via its <see cref="ISupportBinaryImage.ParseBinaryImage"/>        /// method. This header image should also be used to add needed complex state information about the output type being parsed if needed.        /// </para>        /// <para>        /// If there is not enough buffer available to parse common header (as determined by <paramref name="length"/>), return null.  Also, if        /// the protocol allows frame length to be determined at the time common header is being parsed and there is not enough buffer to parse        /// the entire frame, it will be optimal to prevent further parsing by returning null.        /// </para>        /// </remarks>        protected override ICommonHeader<FrameType> ParseCommonHeader(byte[] buffer, int offset, int length)        {            // See if there is enough data in the buffer to parse the common frame header.            if (length < CommonFrameHeader.FixedLength)                return null;             // Parse common frame header            CommonFrameHeader parsedFrameHeader = new(ParseWordCountFromByte, UsePhasorDataFileFormat, m_configurationFrame, buffer, offset, length);             // As an optimization, we also make sure entire frame buffer image is available to be parsed - by doing this            // we eliminate the need to validate length on all subsequent data elements that comprise the frame            if (length < parsedFrameHeader.FrameLength)                return null;             // Expose the frame buffer image in case client needs this data for any reason            OnReceivedFrameBufferImage(parsedFrameHeader.FrameType, buffer, offset, parsedFrameHeader.FrameLength);             // Handle special parsing states            switch (parsedFrameHeader.TypeID)            {                case FrameType.DataFrame:                    // Assign data frame parsing state                    parsedFrameHeader.State = new DataFrameParsingState(parsedFrameHeader.FrameLength, m_configurationFrame, DataCell.CreateNewCell, TrustHeaderLength, ValidateDataFrameCheckSum);                    break;                case FrameType.ConfigurationFrame:                    // Assign configuration frame parsing state                    parsedFrameHeader.State = new ConfigurationFrameParsingState(parsedFrameHeader.FrameLength, m_configurationFileName, ConfigurationCell.CreateNewCell, TrustHeaderLength, ValidateConfigurationFrameCheckSum);                    break;            }             return parsedFrameHeader;        }         // Handler for file watcher - we notify consumer when changes have occurred to configuration file        private void m_configurationFileWatcher_Changed(object sender, FileSystemEventArgs e)        {            // We synchronize change actions - don't want more than one refresh happening at a time...            lock (m_syncLock)            {                // Notify consumer of change in configuration                OnConfigurationChanged();                 // Reload configuration...                m_configurationFrame?.Refresh();            }        }         // Reset file watcher        private void ResetFileWatcher()        {            if (m_configurationFileWatcher is not null)            {                m_configurationFileWatcher.Changed -= m_configurationFileWatcher_Changed;                m_configurationFileWatcher.Dispose();            }             m_configurationFileWatcher = null;             string configurationFile = ConfigurationFileName;             if (!m_refreshConfigurationFileOnChange || string.IsNullOrEmpty(configurationFile) || !File.Exists(configurationFile))                return;             try            {                // Create a new file watcher for configuration file - we'll automatically refresh configuration file when this file gets updated...                m_configurationFileWatcher = new SafeFileWatcher(FilePath.GetDirectoryName(configurationFile), FilePath.GetFileName(configurationFile));                m_configurationFileWatcher.Changed += m_configurationFileWatcher_Changed;                m_configurationFileWatcher.EnableRaisingEvents = true;                m_configurationFileWatcher.IncludeSubdirectories = false;                m_configurationFileWatcher.NotifyFilter = NotifyFilters.LastWrite;            }            catch (Exception ex)            {                OnParsingException(ex);            }        }         /// <summary>        /// Raises the <see cref="FrameParserBase{TypeIndentifier}.ReceivedConfigurationFrame"/> event.        /// </summary>        /// <param name="frame"><see cref="IConfigurationFrame"/> to send to <see cref="FrameParserBase{TypeIndentifier}.ReceivedConfigurationFrame"/> event.</param>        protected override void OnReceivedConfigurationFrame(IConfigurationFrame frame)        {            // We override this method so we can cache configuration frame when it's received            base.OnReceivedConfigurationFrame(frame);             // Cache new configuration frame for parsing subsequent data frames...            if (frame is ConfigurationFrame configurationFrame)                m_configurationFrame = configurationFrame;        }         /// <summary>        /// Casts the parsed <see cref="IChannelFrame"/> to its specific implementation (i.e., <see cref="DataFrame"/> or <see cref="ConfigurationFrame"/>.        /// </summary>        /// <param name="frame"><see cref="IChannelFrame"/> that was parsed by <see cref="FrameImageParserBase{TTypeIdentifier,TOutputType}"/> that implements protocol specific common frame header interface.</param>        protected override void OnReceivedChannelFrame(IChannelFrame frame)        {            // Raise abstract channel frame events as a priority (i.e., IDataFrame, IConfigurationFrame, etc.)            base.OnReceivedChannelFrame(frame);             // Raise BPA PDCstream specific channel frame events, if any have been subscribed            if (frame is null || ReceivedDataFrame is null && ReceivedConfigurationFrame is null)                return;             switch (frame)            {                case DataFrame dataFrame:                {                    ReceivedDataFrame?.Invoke(this, new EventArgs<DataFrame>(dataFrame));                    break;                }                case ConfigurationFrame configFrame:                {                    ReceivedConfigurationFrame?.Invoke(this, new EventArgs<ConfigurationFrame>(configFrame));                    break;                }            }        }         #endregion         #region [ Static ]         // Static Methods         // Attempts to cast given frame into a BPA PDCstream configuration frame - theoretically this will        // allow the same configuration frame to be used for any protocol implementation        internal static ConfigurationFrame CastToDerivedConfigurationFrame(IConfigurationFrame sourceFrame, string configurationFileName)        {            // See if frame is already a BPA PDCstream configuration frame (if so, we don't need to do any work)            if (sourceFrame is ConfigurationFrame derivedFrame)                return derivedFrame;             // Create a new BPA PDCstream configuration frame converted from equivalent configuration information            derivedFrame = new ConfigurationFrame(sourceFrame.Timestamp, configurationFileName, 1, RevisionNumber.Revision2, StreamType.Compact);             foreach (IConfigurationCell sourceCell in sourceFrame.Cells)            {                // Create new derived configuration cell                ConfigurationCell derivedCell = new(derivedFrame, sourceCell.IDCode, sourceCell.NominalFrequency);                 // Create equivalent derived phasor definitions                foreach (IPhasorDefinition sourcePhasor in sourceCell.PhasorDefinitions)                    derivedCell.PhasorDefinitions.Add(new PhasorDefinition(derivedCell, sourcePhasor.Label, sourcePhasor.ScalingValue, sourcePhasor.Offset, sourcePhasor.PhasorType, null));                 // Create equivalent derived frequency definition                IFrequencyDefinition sourceFrequency = sourceCell.FrequencyDefinition;                 if (sourceFrequency is not null)                    derivedCell.FrequencyDefinition = new FrequencyDefinition(derivedCell, sourceFrequency.Label);                 // Create equivalent derived analog definitions (assuming analog type = SinglePointOnWave)                foreach (IAnalogDefinition sourceAnalog in sourceCell.AnalogDefinitions)                    derivedCell.AnalogDefinitions.Add(new AnalogDefinition(derivedCell, sourceAnalog.Label, sourceAnalog.ScalingValue, sourceAnalog.Offset, sourceAnalog.AnalogType));                 // Create equivalent derived digital definitions                foreach (IDigitalDefinition sourceDigital in sourceCell.DigitalDefinitions)                    derivedCell.DigitalDefinitions.Add(new DigitalDefinition(derivedCell, sourceDigital.Label));                 // Add cell to frame                derivedFrame.Cells.Add(derivedCell);            }             return derivedFrame;        }         #endregion    }}