using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Diagnostics;
using System.IO;
using System.Runtime.InteropServices;
using System.Linq;
using System.Text;
using System.Security;

using Microsoft.Win32;

namespace PdfScribeCore
{
 
    public class PdfScribeInstaller
    {
        #region Printer Driver Win32 API Constants

        const uint DRIVER_KERNELMODE = 0x00000001;
        const uint DRIVER_USERMODE =  0x00000002;
        
        const uint APD_STRICT_UPGRADE =  0x00000001;
        const uint APD_STRICT_DOWNGRADE = 0x00000002;
        const uint APD_COPY_ALL_FILES = 0x00000004;
        const uint APD_COPY_NEW_FILES = 0x00000008;
        const uint APD_COPY_FROM_DIRECTORY = 0x00000010;
        
        const uint DPD_DELETE_UNUSED_FILES = 0x00000001;
        const uint DPD_DELETE_SPECIFIC_VERSION = 0x00000002;
        const uint DPD_DELETE_ALL_FILES = 0x00000004;

        #endregion

        //private static readonly TraceSource logEventSource = new TraceSource("PdfScribeCore");
        private readonly TraceSource logEventSource;
        private readonly String logEventSourceNameDefault = "PdfScribeCore";

        const string ENVIRONMENT_64 = "Windows x64";
        const string PRINTERNAME = "PDF Scribe";
        const string DRIVERNAME = "PDF Scribe Virtual Printer";
        const string HARDWAREID = "PDFScribe_Driver0101";
        const string PORTMONITOR = "PDFSCRIBE";
        const string MONITORDLL = "redmon64pdfscribe.dll";
        const string PORTNAME = "PSCRIBE:";
        const string PRINTPROCESOR = "winprint";

        const string DRIVERMANUFACTURER = "S T Chan";
        
        const string DRIVERFILE = "PSCRIPT5.DLL";
        const string DRIVERUIFILE = "PS5UI.DLL";
        const string DRIVERHELPFILE = "PSCRIPT.HLP";
        const string DRIVERDATAFILE = "SCPDFPRN.PPD";
        
        enum DriverFileIndex
        {
            Min = 0,
            DriverFile = Min,
            UIFile,
            HelpFile,
            DataFile,
            Max = DataFile
        };

        readonly String[] printerDriverFiles = new String[] { DRIVERFILE, DRIVERUIFILE, DRIVERHELPFILE, DRIVERDATAFILE };
        readonly String[] printerDriverDependentFiles = new String[] { "PSCRIPT.NTF" };

        #region Error messages for Trace/Debug

        const string FILENOTDELETED_INUSE = "{0} is being used by another process. File was not deleted.";
        const string FILENOTDELETED_UNAUTHORIZED = "{0} is read-only, or its file permissions do not allow for deletion.";

        const string WIN32ERROR = "Win32 error code {0}.";

        const string NATIVE_COULDNOTENABLE64REDIRECTION = "Could not enable 64-bit file system redirection.";
        const string NATIVE_COULDNOTREVERT64REDIRECTION = "Could not revert 64-bit file system redirection.";

        #endregion


        #region Constructors

        public PdfScribeInstaller()
        {
            this.logEventSource = new TraceSource(logEventSourceNameDefault);
        }

        public PdfScribeInstaller(String eventSourceName)
        {
            if (!String.IsNullOrEmpty(eventSourceName))
            {
                this.logEventSource = new TraceSource(eventSourceName);
            }
            else
            {
                throw new ArgumentNullException("eventSourceName");
            }
        }

        #endregion

        #region Port operations

#if DEBUG
        public int AddPdfScribePort_Test()
        {
            return AddPdfScribePort();
        }
#endif

        private int AddPdfScribePort()
        {
            return DoXcvDataPortOperation(PORTNAME, PORTMONITOR, "AddPort");
        }

        public void DeletePdfScribePort()
        {
            DoXcvDataPortOperation(PORTNAME, PORTMONITOR, "DeletePort");
        }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="portName"></param>
        /// <param name="xcvDataOperation"></param>
        /// <returns></returns>
        /// <remarks>I can't remember the name of the coder who wrote this code originally</remarks>
        private int DoXcvDataPortOperation(string portName, string portMonitor, string xcvDataOperation)
        {

            int win32ErrorCode;

            PRINTER_DEFAULTS def = new PRINTER_DEFAULTS();

            def.pDatatype = null;
            def.pDevMode = IntPtr.Zero;
            def.DesiredAccess = 1; //Server Access Administer

            IntPtr hPrinter = IntPtr.Zero;

            if (NativeMethods.OpenPrinter(",XcvMonitor " + portMonitor, ref hPrinter, def) != 0)
            {
                if (!portName.EndsWith("\0"))
                    portName += "\0"; // Must be a null terminated string

                // Must get the size in bytes. Rememeber .NET strings are formed by 2-byte characters
                uint size = (uint)(portName.Length * 2);

                // Alloc memory in HGlobal to set the portName
                IntPtr portPtr = Marshal.AllocHGlobal((int)size);
                Marshal.Copy(portName.ToCharArray(), 0, portPtr, portName.Length);

                uint needed; // Not that needed in fact...
                uint xcvResult; // Will receive de result here

                NativeMethods.XcvData(hPrinter, xcvDataOperation, portPtr, size, IntPtr.Zero, 0, out needed, out xcvResult);

                NativeMethods.ClosePrinter(hPrinter);
                Marshal.FreeHGlobal(portPtr);
                win32ErrorCode = (int)xcvResult;
            }
            else
            {
                win32ErrorCode = Marshal.GetLastWin32Error();
            }
            return win32ErrorCode;

        }

        #endregion

        #region Port Monitor

        /// <summary>
        /// Adds the PDF Scribe port monitor
        /// </summary>
        /// <param name="monitorFilePath">Directory where the uninstalled monitor dll is located</param>
        /// <returns>true if the monitor is installed, false if install failed</returns>
        public bool AddPdfScribePortMonitor(String monitorFilePath)
        {
            bool monitorAdded = false;

            IntPtr oldRedirectValue = IntPtr.Zero;

            try
            {
                oldRedirectValue = DisableWow64Redirection();
                if (!DoesMonitorExist(PORTMONITOR))
                {
                    // Copy the monitor DLL to
                    // the system directory
                    String fileSourcePath = Path.Combine(monitorFilePath, MONITORDLL);
                    String fileDestinationPath = Path.Combine(Environment.SystemDirectory, MONITORDLL);
                    try
                    {
                        File.Copy(fileSourcePath, fileDestinationPath, true);
                    }
                    catch (IOException)
                    {
                        // File in use, log -
                        // this is OK because it means the file is already there
                    }
                    MONITOR_INFO_2 newMonitor = new MONITOR_INFO_2();
                    newMonitor.pName = PORTMONITOR;
                    newMonitor.pEnvironment = ENVIRONMENT_64;
                    newMonitor.pDLLName = MONITORDLL;
                    if (!AddPortMonitor(newMonitor))
                        throw new Win32Exception(Marshal.GetLastWin32Error(), String.Format("Could not add port monitor {0}", PORTMONITOR));
                    else
                        monitorAdded = true;
                }

            }
            finally
            {
                if (oldRedirectValue != IntPtr.Zero) RevertWow64Redirection(oldRedirectValue);
            }


            return monitorAdded;
        }


        /// <summary>
        /// Disables WOW64 system directory file redirection
        /// if the current process is both
        /// 32-bit, and running on a 64-bit OS
        /// </summary>
        /// <returns>A Handle, which should be retained to reenable redirection</returns>
        private IntPtr DisableWow64Redirection()
        {
            IntPtr oldValue = IntPtr.Zero;
            if (Environment.Is64BitOperatingSystem && !Environment.Is64BitProcess)
                if (!NativeMethods.Wow64DisableWow64FsRedirection(ref oldValue))
                    throw new Win32Exception(Marshal.GetLastWin32Error(), "Could not disable Wow64 file system redirection.");
            return oldValue;
        }

        /// <summary>
        /// Reenables WOW64 system directory file redirection
        /// if the current process is both
        /// 32-bit, and running on a 64-bit OS
        /// </summary>
        /// <param name="oldValue">A Handle value - should be retained from call to <see cref="DisableWow64Redirection"/></param>
        private void RevertWow64Redirection(IntPtr oldValue)
        {
            if (Environment.Is64BitOperatingSystem && !Environment.Is64BitProcess)
            {
                if (!NativeMethods.Wow64RevertWow64FsRedirection(oldValue))
                {
                    throw new Win32Exception(Marshal.GetLastWin32Error(), "Could not reenable Wow64 file system redirection.");
                }
            }
        }

        /// <summary>
        /// Removes the PDF Scribe port monitor
        /// </summary>
        /// <returns>true if monitor successfully removed, false if removal failed</returns>
        public bool RemovePdfScribePortMonitor()
        {
            bool monitorRemoved = false;
            if ((NativeMethods.DeleteMonitor(null, ENVIRONMENT_64, PORTMONITOR)) != 0)
                monitorRemoved = true;
            return monitorRemoved;
        }

        private bool DeletePdfScribePortMonitorDll()
        {
            return DeletePortMonitorDll(MONITORDLL);
        }

        private bool DeletePortMonitorDll(String monitorDll)
        {
            bool monitorDllRemoved = false;

            String monitorDllFullPathname = String.Empty;
            IntPtr oldRedirectValue = IntPtr.Zero;
            try
            {
                oldRedirectValue = DisableWow64Redirection();

                monitorDllFullPathname = Path.Combine(Environment.SystemDirectory, monitorDll);
                
                File.Delete(monitorDllFullPathname);
                monitorDllRemoved = true;
            }
            catch (Win32Exception windows32Ex)
            {
                // This one is likely very bad -
                // log and rethrow so we don't continue
                // to try to uninstall
                logEventSource.TraceEvent(TraceEventType.Critical, 
                                          (int)TraceEventType.Critical, 
                                          NATIVE_COULDNOTENABLE64REDIRECTION + String.Format(WIN32ERROR, windows32Ex.NativeErrorCode.ToString()));
                throw;
            }
            catch (IOException)
            {
                // File still in use
                logEventSource.TraceEvent(TraceEventType.Error, (int)TraceEventType.Error, String.Format(FILENOTDELETED_INUSE, monitorDllFullPathname));  
            }
            catch (UnauthorizedAccessException)
            {
                // File is readonly, or file permissions do not allow delete
                logEventSource.TraceEvent(TraceEventType.Error, (int)TraceEventType.Error, String.Format(FILENOTDELETED_INUSE, monitorDllFullPathname));
            }
            finally
            {
                try
                {
                    if (oldRedirectValue != IntPtr.Zero) RevertWow64Redirection(oldRedirectValue);
                }
                catch (Win32Exception windows32Ex)
                {
                    // Couldn't turn file redirection back on -
                    // this is not good
                    logEventSource.TraceEvent(TraceEventType.Critical, 
                                              (int)TraceEventType.Critical, 
                                              NATIVE_COULDNOTREVERT64REDIRECTION + String.Format(WIN32ERROR, windows32Ex.NativeErrorCode.ToString()));
                    throw;
                }
            }

            return monitorDllRemoved;

        }

        private bool AddPortMonitor(MONITOR_INFO_2 newMonitor)
        {
            bool monitorAdded = false;
            if ((NativeMethods.AddMonitor(null, 2, ref newMonitor) != 0))
            {
                monitorAdded = true;
            }
            return monitorAdded;
        }

        private bool DeletePortMonitor(String monitorName)
        {
            bool monitorDeleted = false;
            if ((NativeMethods.DeleteMonitor(null, ENVIRONMENT_64, monitorName)) != 0)
            {
                monitorDeleted = true;
            }
            return monitorDeleted;
        }

        private bool DoesMonitorExist(String monitorName)
        {
            bool monitorExists = false;
            List<MONITOR_INFO_2> portMonitors = EnumerateMonitors();
            foreach (MONITOR_INFO_2 portMonitor in portMonitors)
            {
                if (portMonitor.pName == monitorName)
                {
                    monitorExists = true;
                    break;
                }
            }
            return monitorExists;
        }

        public List<MONITOR_INFO_2> EnumerateMonitors()
        {
            List<MONITOR_INFO_2> portMonitors = new List<MONITOR_INFO_2>();

            uint pcbNeeded = 0;
            uint pcReturned = 0;

            if (!NativeMethods.EnumMonitors(null, 2, IntPtr.Zero, 0, ref pcbNeeded, ref pcReturned))
            {
                IntPtr pMonitors = Marshal.AllocHGlobal((int)pcbNeeded);
                if (NativeMethods.EnumMonitors(null, 2, pMonitors, pcbNeeded, ref pcbNeeded, ref pcReturned))
                {
                    IntPtr currentMonitor = pMonitors;

                    for (int i = 0; i < pcReturned; i++)
                    {
                        portMonitors.Add((MONITOR_INFO_2)Marshal.PtrToStructure(currentMonitor, typeof(MONITOR_INFO_2)));
                        currentMonitor = (IntPtr)(currentMonitor.ToInt32() + Marshal.SizeOf(typeof(MONITOR_INFO_2)));
                    }
                    Marshal.FreeHGlobal(pMonitors);

                }
                else
                {
                    // Failed to retrieve enumerate
                    throw new Win32Exception(Marshal.GetLastWin32Error(), "Could not enumerate monitor ports.");
                }

            }
            else
            {
                throw new ApplicationException("Call to EnumMonitors in winspool.drv succeeded with a zero size buffer - unexpected error.");
            }

            return portMonitors;
        }

        #endregion

        #region Printer Install

        public String RetrievePrinterDriverDirectory()
        {
            StringBuilder driverDirectory = new StringBuilder(1024);
            int dirSizeInBytes = 0;
            if (!NativeMethods.GetPrinterDriverDirectory(null,
                                                         null,
                                                         1,
                                                         driverDirectory,
                                                         1024,
                                                         ref dirSizeInBytes))
                throw new ApplicationException("Could not retrieve printer driver directory.");
            return driverDirectory.ToString();
        }

#if DEBUG
        public bool InstallSoftscanPrinter_Test()
        {
            String driverSourceDirectory = @"C:\Code\PdfScribe\Lib\";
            return InstallPdfScribePrinter(driverSourceDirectory);
        }
#endif

        /// <summary>
        /// Installs the port monitor, port,
        /// printer drivers, and PDF Scribe virtual printer
        /// </summary>
        /// <param name="driverSourceDirectory">Directory where the uninstalled printer driver files are located</param>
        /// <param name="driverFilesToCopy">An array containing the printer driver's filenames</param>
        /// <param name="dependentFilesToCopy">An array containing dependent filenames</param>
        /// <returns>true if printer installed, false if failed</returns>
        public bool InstallPdfScribePrinter(String driverSourceDirectory)
        {

            bool printerInstalled = false;


            String driverDirectory = RetrievePrinterDriverDirectory();
            if (AddPdfScribePortMonitor(driverSourceDirectory))
            {
                
                //if (CopyPrinterDriverFiles(driverSourceDirectory, driverFilesToCopy.Concat(dependentFilesToCopy).ToArray()))
                if (CopyPrinterDriverFiles(driverSourceDirectory, printerDriverFiles.Concat(printerDriverDependentFiles).ToArray()))
                {
                    if (AddPdfScribePort() == 0)
                    {
                        if (InstallPdfScribePrinterDriver())
                        {
                            if (AddPdfScribePrinter())
                            {
                                if (ConfigurePdfScribePort())
                                {
                                    printerInstalled = true;
                                }
                                else
                                {
                                    // Failed to configure port
                                }
                            }
                            else
                            {
                                // Failed to install printer
                            }
                        }
                        else
                        {
                            // Failed to install printer driver
                        }
                    }
                    else
                    {
                        // Failed to add printer port
                    }
                }
                else
                {
                    //Failed to copy printer driver files
                }
            }
            else
            {
                //Failed to add port monitor
            }
            return printerInstalled;
        }


        /// <summary>
        /// 
        /// </summary>
        /// <returns></returns>
        public bool UninstallPdfScribePrinter()
        {
            bool printerUninstalled = false;

            DeletePdfScribePrinter();
            RemovePDFScribePrinterDriver();
            DeletePdfScribePort();
            RemovePdfScribePortMonitor();
            RemovePdfScribePortConfig();
            return printerUninstalled;
        }

        private bool CopyPrinterDriverFiles(String driverSourceDirectory,
                                            String[] filesToCopy)
        {
            bool filesCopied = false;
            String driverDestinationDirectory = RetrievePrinterDriverDirectory();
            try
            {
                for (int loop = 0; loop < filesToCopy.Length; loop++)
                {
                    String fileSourcePath = Path.Combine(driverSourceDirectory, filesToCopy[loop]);
                    String fileDestinationPath = Path.Combine(driverDestinationDirectory, filesToCopy[loop]);
                    try
                    {
                        File.Copy(fileSourcePath, fileDestinationPath);
                    }
                    catch (IOException)
                    {
                        // Just keep going - file was already
                        // there, but we didn't overwrite
                        continue;
                    }
                }
                filesCopied = true;
            }
            catch (UnauthorizedAccessException)
            { }
            catch (PathTooLongException)
            { }
            catch (DirectoryNotFoundException)
            { }
            catch (FileNotFoundException)
            { }
            catch (NotSupportedException)
            { }


            return filesCopied;
        }

        private bool DeletePrinterDriverFiles(String driverSourceDirectory,
                                              String[] filesToDelete)
        {
            bool allFilesDeleted = true;
            for (int loop = 0; loop < filesToDelete.Length; loop++)
            {
                try
                {
                    File.Delete(Path.Combine(driverSourceDirectory, filesToDelete[loop]));
                }
                catch
                {
                    allFilesDeleted = false;
                }
            }
            return allFilesDeleted;
        }


        private bool InstallPdfScribePrinterDriver()
        {

            String driverSourceDirectory = RetrievePrinterDriverDirectory();

            StringBuilder nullTerminatedDependentFiles = new StringBuilder();
            if (printerDriverDependentFiles.Length > 0)
            {
                for (int loop = 0; loop <= printerDriverDependentFiles.GetUpperBound(0); loop++)
                {
                    nullTerminatedDependentFiles.Append(printerDriverDependentFiles[loop]);
                    nullTerminatedDependentFiles.Append("\0");
                }
                nullTerminatedDependentFiles.Append("\0");
            }
            else
            {
                nullTerminatedDependentFiles.Append("\0\0");
            }

            DRIVER_INFO_6 printerDriverInfo = new DRIVER_INFO_6();

            printerDriverInfo.cVersion = 3;
            printerDriverInfo.pName = DRIVERNAME;
            printerDriverInfo.pEnvironment = ENVIRONMENT_64;
            printerDriverInfo.pDriverPath = Path.Combine(driverSourceDirectory, DRIVERFILE);
            printerDriverInfo.pConfigFile = Path.Combine(driverSourceDirectory, DRIVERUIFILE);
            printerDriverInfo.pHelpFile = Path.Combine(driverSourceDirectory, DRIVERHELPFILE);
            printerDriverInfo.pDataFile = Path.Combine(driverSourceDirectory, DRIVERDATAFILE);
            printerDriverInfo.pDependentFiles = nullTerminatedDependentFiles.ToString();

            printerDriverInfo.pMonitorName = PORTMONITOR;
            printerDriverInfo.pDefaultDataType = String.Empty;
            printerDriverInfo.dwlDriverVersion = 0x0000000200000000U;
            printerDriverInfo.pszMfgName = DRIVERMANUFACTURER;
            printerDriverInfo.pszHardwareID = HARDWAREID;
            printerDriverInfo.pszProvider = DRIVERMANUFACTURER;


            return InstallPrinterDriver(ref printerDriverInfo);
        }

        private bool InstallPrinterDriver(ref DRIVER_INFO_6 printerDriverInfo)
        {
            bool printerDriverInstalled = false;

            printerDriverInstalled = NativeMethods.AddPrinterDriver(null, 6, ref printerDriverInfo);
            if (printerDriverInstalled == false)
            {
                int lastWinError = Marshal.GetLastWin32Error();
                throw new Win32Exception(Marshal.GetLastWin32Error(), "Could not add printer PDF Scribe printer driver.");
            }
            return printerDriverInstalled;
        }

        public bool RemovePDFScribePrinterDriver()
        {
            bool driverRemoved = NativeMethods.DeletePrinterDriverEx(null, ENVIRONMENT_64, DRIVERNAME, DPD_DELETE_UNUSED_FILES, 3);
            if (!driverRemoved)
            {
                throw new Win32Exception(Marshal.GetLastWin32Error(), "Could not remove PDF Scribe printer driver");
            }
            return driverRemoved;
        }


        private bool AddPdfScribePrinter()
        {
            bool printerAdded = false;
            PRINTER_INFO_2 pdfScribePrinter = new PRINTER_INFO_2();

            pdfScribePrinter.pServerName = null;
            pdfScribePrinter.pPrinterName = PRINTERNAME;
            pdfScribePrinter.pPortName = PORTNAME;
            pdfScribePrinter.pDriverName = DRIVERNAME;
            pdfScribePrinter.pPrintProcessor = PRINTPROCESOR;
            pdfScribePrinter.pDatatype = "RAW";
            pdfScribePrinter.Attributes = 0x00000002;

            int softScanPrinterHandle = NativeMethods.AddPrinter(null, 2, ref pdfScribePrinter);
            if (softScanPrinterHandle != 0)
            {
                // Added ok
                int closeCode = NativeMethods.ClosePrinter((IntPtr)softScanPrinterHandle);
                printerAdded = true;
            }
            else
            {
                throw new Win32Exception(Marshal.GetLastWin32Error(), "Could not add PDF Scribe virtual printer.");
            }
            return printerAdded;
        }

        private bool DeletePdfScribePrinter()
        {
            bool printerDeleted = false;

            PRINTER_DEFAULTS scribeDefaults = new PRINTER_DEFAULTS();
            scribeDefaults.DesiredAccess = 0x000F000C; // All access
            scribeDefaults.pDatatype = null;
            scribeDefaults.pDevMode = IntPtr.Zero;

            IntPtr scribeHandle = IntPtr.Zero;
            try
            {
                if (NativeMethods.OpenPrinter(PRINTERNAME, ref scribeHandle, scribeDefaults) != 0)
                {
                    if (NativeMethods.DeletePrinter(scribeHandle))
                        printerDeleted = true;
                }
                else
                {
                    // log error
                }
            }
            finally
            {
                if (scribeHandle != IntPtr.Zero) NativeMethods.ClosePrinter(scribeHandle);
            }
            return printerDeleted;
        }
        #endregion


        #region Configuration and Registry changes

#if DEBUG
        public bool ConfigurePdfScribePort_Test()
        {
            return ConfigurePdfScribePort();
        }
#endif

        private bool ConfigurePdfScribePort()
        {
            bool registryChangesMade = false;
            // Add all the registry info
            // for the port and monitor
            RegistryKey portConfiguration;
            try
            {
                portConfiguration = Registry.LocalMachine.CreateSubKey("SYSTEM\\CurrentControlSet\\Control\\Print\\Monitors\\" + 
                                                                                PORTMONITOR +
                                                                                "\\Ports\\" + PORTNAME);
                portConfiguration.SetValue("Description", "PDF Scribe", RegistryValueKind.String);
                portConfiguration.SetValue("Command", "", RegistryValueKind.String);
                portConfiguration.SetValue("Arguments", "", RegistryValueKind.String);
                portConfiguration.SetValue("Printer", "", RegistryValueKind.String);
                portConfiguration.SetValue("Output", 0, RegistryValueKind.DWord);
                portConfiguration.SetValue("ShowWindow", 0, RegistryValueKind.DWord);
                portConfiguration.SetValue("RunUser", 1, RegistryValueKind.DWord);
                portConfiguration.SetValue("Delay", 300, RegistryValueKind.DWord);
                portConfiguration.SetValue("LogFileUse", 0, RegistryValueKind.DWord);
                portConfiguration.SetValue("LogFileName", "", RegistryValueKind.String);
                portConfiguration.SetValue("LogFileDebug", 0, RegistryValueKind.DWord);
                portConfiguration.SetValue("PrintError", 0, RegistryValueKind.DWord);
                registryChangesMade = true;
            }

            catch (UnauthorizedAccessException)
            { }
            catch (SecurityException)
            { }

            return registryChangesMade;
        }

        private bool RemovePdfScribePortConfig()
        {
            bool registryEntriesRemoved = false;

            try
            {
                Registry.LocalMachine.DeleteSubKey("SYSTEM\\CurrentControlSet\\Control\\Print\\Monitors\\" +
                                                    PORTMONITOR + "\\Ports\\" + PORTNAME, false);
                registryEntriesRemoved = true;
            }
            catch (UnauthorizedAccessException)
            { }

            return registryEntriesRemoved;

        }

        #endregion

    }
}