/*
 * FileCore.cpp
 *
 *  Created on: 1 Jun 2016
 *      Author: wentzelc
 */

// Standard C/C++ Libraries
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>

// redA Libraries
#include "ApplicationCore.h"
#include "FileCore.h"

//---------------------------------------------------------------------------

// Global Vars
extern char         * ProcessName;
//extern CApplication * Application;

//---------------------------------------------------------------------------

// Function Constructor
CFunctionCore * NewFileCore( const char * Name ) {
    return (CFunctionCore*) new CFileCore( Name );
}
//---------------------------------------------------------------------------

CFileCore::CFileCore( const char * pName, const char * pType ) : CFunctionCore( pName, pType )
{
    FirstFile = NULL;
}
//---------------------------------------------------------------------------

CFileCore::~CFileCore()
{
    TFileHandle   * NextFile  = NULL;

    // Destroy file specs
    while (FirstFile)
    {
        // Close file if open
        CloseFile( FirstFile );

        // Destroy file parameters
        if (FirstFile->Name)
            free( FirstFile->Name );
        if (FirstFile->Path)
            free( FirstFile->Path );

        // Destroy File
        NextFile = FirstFile->Next;
        delete FirstFile;
        FirstFile = NextFile;
    }
}
//---------------------------------------------------------------------------

TFileHandle *  CFileCore::AddFile( const char * Name, const char * Path, bool Append, bool CreateChannel )
{
    TFileHandle   ** FileHandle     = NULL;

    // Validate
    if (!Name || !*Name || !Path || !*Path) {
        return NULL;
    }

    // Find File or End of list
    FileHandle = &FirstFile;
    while (*FileHandle && strcmp( Name, (*FileHandle)->Name )) {
        FileHandle = &((*FileHandle)->Next);
    }

    // Check if found
    if (!*FileHandle)
    {
        // Create new
        *FileHandle = (TFileHandle*)calloc( 1, sizeof(TFileHandle) );

        // Set name & Path
        (*FileHandle)->Name = strdup( Name );
        (*FileHandle)->Path = strdup( Path );
    }

    // Create Channel if necessary
    if (CreateChannel) {
        AddChannel( Name, CH_ready );
    }

    // Set Parameters
    (*FileHandle)->Append     = Append;
    (*FileHandle)->FD         = NO_FD;

    // Return File
    return (*FileHandle);
}
//---------------------------------------------------------------------------

bool CFileCore::SetFilePersistence( TFileHandle * FileHandle, bool Persistent, int PersistTimeout )
{
    // Validate
    if (!FileHandle) {
        return false;
    }

    // Set parameters
    FileHandle->Persistent = Persistent;
    FileHandle->PersistTimeout = PersistTimeout;

    // Open persistent file
    if (Persistent && (!PersistTimeout)) {
        OpenFile( FileHandle );
        SetStartTime( &(FileHandle->PersistTime) );
    }
    // Close non-persistent file
    else if (!Persistent && isOpen(FileHandle)) {
        CloseFile( FileHandle );
    }

    return true;
}
//---------------------------------------------------------------------------

bool CFileCore::OpenFile( TFileHandle * FileHandle )
{
    // Validate
    if (!FileHandle) {
        return false;
    }

    // Open file if not already open
    if (!isOpen( FileHandle ))
    {
        // GEt file handle
        (FileHandle)->FD = open( FileHandle->Path, O_WRONLY | O_CREAT | ((FileHandle->Append)? O_APPEND : O_TRUNC), 0664 );

        // Report event
        if (isOpen(FileHandle))
        {
            // Set timer
            SetStartTime( &(FileHandle->PersistTime) );

            // Report result
            if (Log)  Log->Message( LogLevel, dlHigh, "%s/%s: File '%s' - Opened",
                                    ProcessName, Name, FileHandle->Name );
        }
    }

    // Check if failed
    if (!isOpen(FileHandle))
    {
        // Report result
        if (Log)  Log->Message( LogLevel, dlHigh, "%s/%s: File '%s' - Could not open (%d) %s",
                                ProcessName, Name, FileHandle->Name, errno, strerror(errno) );
        return false;
    }

    return true;
}
//---------------------------------------------------------------------------

bool CFileCore::CloseFile( TFileHandle * FileHandle )
{
    // Validate
    if (!FileHandle) {
        return false;
    }

    // Close file if not already open
    if (isOpen(FileHandle))
    {
        // Close file
        close( FileHandle->FD );
        FileHandle->FD = NO_FD;

        // Report result
        if (!isOpen(FileHandle)) {
            if (Log)  Log->Message( LogLevel, dlHigh, "%s/%s: File '%s' - Closed",
                                    ProcessName, Name, FileHandle->Name );
        } else {
            if (Log)  Log->Message( LogLevel, dlHigh, "%s/%s: File '%s' - Could not close",
                                    ProcessName, Name, FileHandle->Name );
        }
    }
    return true;
}
//---------------------------------------------------------------------------

int CFileCore::ReadFromFD( int FD, char * Data, int MaxLen )
{
    int     BytesRead       = 0;
    int     TotalRead       = 0;
    int     DataRemain      = MaxLen;
    bool    Error           = false;

    // Check if buffer created
    if ((FD == -1) || !Data) {
        return 0;
    }

    // Read Data into buffer
    while (DataRemain)
    {
        // Read from file descriptor
        BytesRead = read( FD, &Data[TotalRead], DataRemain );
        if (BytesRead <= 0) {
            Error = true;
            errno = (!BytesRead)? 0 : errno;        // No error if no bytes written
            break;
        }

        // Update Data Pointers
        TotalRead += BytesRead;
        DataRemain -= BytesRead;

        if (DataRemain) {
            usleep( 500 );
        }
    }

    return (Error)? -TotalRead : TotalRead;         // Report negative total on error
}
//---------------------------------------------------------------------------

int CFileCore::WriteToFD( int FD, const char * Data, int Len )
{
    int     BytesWritten    = 0;
    int     TotalWritten    = 0;
    int     DataRemain      = (Len != -1)? Len : (Data)? strlen(Data) : 0;
    bool    Error           = false;

    // Check if buffer created
    if ((FD == -1) || !DataRemain) {
        return 0;
    }

    // Read Data into buffer
    while (DataRemain)
    {
        // Read from file descriptor
        BytesWritten = write( FD, &Data[TotalWritten], DataRemain );
        if ((BytesWritten <= 0) && (errno != EAGAIN)) {
            Error = true;
            errno = (!BytesWritten)? 0 : errno;     // No error if no bytes written
            break;
        }

        // Update Data Pointers
        TotalWritten += BytesWritten;
        DataRemain -= BytesWritten;

        if (DataRemain) {
            usleep( 500 );
        }
    }
    return (Error)? -TotalWritten : TotalWritten;    // Report negative total on error
}
//---------------------------------------------------------------------------

// Manual Data Input/Output
int CFileCore::Input( const char * ChannelName, const char * SourceRef, const char * Data, int Len )
{
    TFileHandle   * FileHandle      = NULL;
    int         BytesWritten    = 0;

    // Validate
    if (!ChannelName || !Data) {
        return 0;
    }
    else if (Len == -1) {
        Len = strlen( Data );
    };

    // Get Channel
    if (!(FileHandle = GetFile( ChannelName )))
    {
        // Log event
        if (Log)  Log->Message( LogLevel, dlHigh, "%s/%s: Channel '%s' - Input rejected, Channel not found",
                                ProcessName, Name, ChannelName );
        return 0;
    }

    // Log event
    if (Log)  Log->Output( LogLevel, dlHigh, LogOutput, Data, Len, "%s/%s: Channel '%s' - IN:",
                           ProcessName, Name, ChannelName );

    // Open file
    if (!OpenFile( FileHandle )) {
        return 0;
    }

    // Handle Incoming data
    BytesWritten = WriteToFD( FileHandle->FD, Data, Len );
    SetStartTime( &(FileHandle->PersistTime) );

    // Return processed bytes
    return BytesWritten;
}
//---------------------------------------------------------------------------

bool CFileCore::Process()
{
    TFileHandle     * FileHandle;

    // Close Persistent files not used
    FileHandle = FirstFile;
    while (FileHandle)
    {
        if (isOpen(FileHandle) &&
            (!FileHandle->Persistent ||
             (FileHandle->PersistTimeout && Timeout( FileHandle->PersistTime, FileHandle->PersistTimeout )))) {
            CloseFile( FileHandle );
        }

        // Next
        FileHandle = FileHandle->Next;
    }

    return true;
}
//---------------------------------------------------------------------------