#include "unixprocess_impl.h"

#if defined(__WXMAC__)||defined(__WXGTK__)

#include <wx/stdpaths.h>
#include <wx/filename.h>
#include <unistd.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/select.h>
#include <errno.h>
#include <sys/wait.h>
#include <string.h>
#include "procutils.h"

#ifdef __WXGTK__
#ifdef __FreeBSD__
#    include <sys/ioctl.h>
#    include <termios.h>
#    include <libutil.h>
#else
#    include <pty.h>
#    include <utmp.h>
#endif
#else
#    include <util.h>
#endif

static char  **argv = NULL;
static int    argc = 0;

// ----------------------------------------------
#define ISBLANK(ch) ((ch) == ' ' || (ch) == '\t')
#define BUFF_SIZE  1024*64

/*  Routines imported from standard C runtime libraries. */

#ifdef __STDC__

#include <stddef.h>
#include <string.h>
#include <stdlib.h>

#else	/* !__STDC__ */

#if !defined _WIN32 || defined __GNUC__
extern char *memcpy ();		/* Copy memory region */
extern int strlen ();		/* Count length of string */
extern char *malloc ();		/* Standard memory allocater */
extern char *realloc ();	/* Standard memory reallocator */
extern void free ();		/* Free malloc'd memory */
extern char *strdup ();		/* Duplicate a string */
#endif

#endif	/* __STDC__ */


#ifndef NULL
#define NULL 0
#endif

#ifndef EOS
#define EOS '\0'
#endif

#define INITIAL_MAXARGC 8	/* Number of args + NULL in initial argv */

static void freeargv (char **vector)
{
    register char **scan;

    if (vector != NULL) {
        for (scan = vector; *scan != NULL; scan++) {
            free (*scan);
        }
        free (vector);
    }
}

char **
dupargv (char **argv)
{
    int argc;
    char **copy;

    if (argv == NULL)
        return NULL;

    /* the vector */
    for (argc = 0; argv[argc] != NULL; argc++);
    copy = (char **) malloc ((argc + 1) * sizeof (char *));
    if (copy == NULL)
        return NULL;

    /* the strings */
    for (argc = 0; argv[argc] != NULL; argc++) {
        int len = strlen (argv[argc]);
        copy[argc] = (char*)malloc (sizeof (char *) * (len + 1));
        if (copy[argc] == NULL) {
            freeargv (copy);
            return NULL;
        }
        strcpy (copy[argc], argv[argc]);
    }
    copy[argc] = NULL;
    return copy;
}

char **buildargv (const char *input)
{
    char *arg;
    char *copybuf;
    int squote = 0;
    int dquote = 0;
    int bsquote = 0;
    int argc = 0;
    int maxargc = 0;
    char **argv = NULL;
    char **nargv;

    if (input != NULL) {
        copybuf = (char *) alloca (strlen (input) + 1);
        /* Is a do{}while to always execute the loop once.  Always return an
        argv, even for null strings.  See NOTES above, test case below. */
        do {
            /* Pick off argv[argc] */
            while (ISBLANK (*input)) {
                input++;
            }
            if ((maxargc == 0) || (argc >= (maxargc - 1))) {
                /* argv needs initialization, or expansion */
                if (argv == NULL) {
                    maxargc = INITIAL_MAXARGC;
                    nargv = (char **) malloc (maxargc * sizeof (char *));
                } else {
                    maxargc *= 2;
                    nargv = (char **) realloc (argv, maxargc * sizeof (char *));
                }
                if (nargv == NULL) {
                    if (argv != NULL) {
                        freeargv (argv);
                        argv = NULL;
                    }
                    break;
                }
                argv = nargv;
                argv[argc] = NULL;
            }
            /* Begin scanning arg */
            arg = copybuf;
            while (*input != EOS) {
                if (ISBLANK (*input) && !squote && !dquote && !bsquote) {
                    break;
                } else {
                    if (bsquote) {
                        bsquote = 0;
                        *arg++ = *input;
                    } else if (*input == '\\') {
                        bsquote = 1;
                    } else if (squote) {
                        if (*input == '\'') {
                            squote = 0;
                        } else {
                            *arg++ = *input;
                        }
                    } else if (dquote) {
                        if (*input == '"') {
                            dquote = 0;
                        } else {
                            *arg++ = *input;
                        }
                    } else {
                        if (*input == '\'') {
                            squote = 1;
                        } else if (*input == '"') {
                            dquote = 1;
                        } else {
                            *arg++ = *input;
                        }
                    }
                    input++;
                }
            }
            *arg = EOS;
            argv[argc] = strdup (copybuf);
            if (argv[argc] == NULL) {
                freeargv (argv);
                argv = NULL;
                break;
            }
            argc++;
            argv[argc] = NULL;

            while (ISBLANK (*input)) {
                input++;
            }
        } while (*input != EOS);
    }
    return (argv);
}

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

static void make_argv(const wxString &cmd)
{
    if(argc) {
        freeargv(argv);
        argc=0;
    }

    argv = buildargv(cmd.mb_str(wxConvUTF8).data());
    argc=0;

    for (char **targs = argv; *targs != NULL; targs++) {
        argc++;
    }
}

#define BUFF_STATE_NORMAL 0
#define BUFF_STATE_IN_ESC 1

static void RemoveTerminalColoring(char *buffer)
{
    char *saved_buff = buffer;
    char tmpbuf[BUFF_SIZE+1];
    memset(tmpbuf, 0, sizeof(tmpbuf));

    short state = BUFF_STATE_NORMAL;
    size_t i(0);

    while(*buffer != 0) {
        switch (state) {
        case BUFF_STATE_NORMAL:
            if(*buffer == 0x1B) { // found ESC char
                state = BUFF_STATE_IN_ESC;

            } else {
                tmpbuf[i] = *buffer;
                i++;
            }
            break;
        case BUFF_STATE_IN_ESC:
            if(*buffer == 'm') { // end of color sequence
                state = BUFF_STATE_NORMAL;
            }
            break;
        }
        buffer++;
    }
    memset(saved_buff, 0, BUFF_SIZE);
    memcpy(saved_buff, tmpbuf, strlen(tmpbuf));
}

UnixProcessImpl::UnixProcessImpl(wxEvtHandler *parent)
    : IProcess(parent)
    , m_readHandle  (-1)
    , m_writeHandle (-1)
    , m_thr         (NULL)
{
}

UnixProcessImpl::~UnixProcessImpl()
{
    Cleanup();
}

void UnixProcessImpl::Cleanup()
{
    close(GetReadHandle());
    close(GetWriteHandle());

    if ( m_thr ) {
        // Stop the reader thread
        m_thr->Stop();
        delete m_thr;
    }
    m_thr = NULL;

    if(GetPid() != wxNOT_FOUND) {
        wxKill(GetPid(), GetHardKill() ? wxSIGKILL : wxSIGTERM, NULL, wxKILL_CHILDREN);
        // The Zombie cleanup is done in app.cpp in ::ChildTerminatedSingalHandler() signal handler
        int status(0);
        waitpid(-1, &status, WNOHANG);
    }
}

bool UnixProcessImpl::IsAlive()
{
    return kill(m_pid, 0) == 0;
}

bool UnixProcessImpl::Read(wxString& buff)
{
    fd_set  rs;
    timeval timeout;

    memset(&rs, 0, sizeof(rs));
    FD_SET(GetReadHandle(), &rs);
    timeout.tv_sec  = 0;      // 0 seconds
    timeout.tv_usec = 150000; // 150 ms

    int errCode(0);
    errno = 0;

    int rc = select(GetReadHandle()+1, &rs, NULL, NULL, &timeout);
    errCode = errno;
    if ( rc == 0 ) {
        // timeout
        return true;

    } else if ( rc > 0 ) {
        // there is something to read
        char buffer[BUFF_SIZE+1]; // our read buffer
        memset(buffer, 0, sizeof(buffer));
        if(read(GetReadHandle(), buffer, sizeof(buffer)) > 0) {
            buff.Empty();
            buffer[BUFF_SIZE] = 0; // allways place a terminator

            // Remove coloring chars from the incomnig buffer
            // colors are marked with ESC and terminates with lower case 'm'
            RemoveTerminalColoring(buffer);

            wxString convBuff = wxString(buffer, wxConvUTF8);
            if(convBuff.IsEmpty()) {
                convBuff = wxString::From8BitData(buffer);
            }

            buff.Append( convBuff );
            return true;
        }
        return false;

    } else {

        if ( errCode == EINTR || errCode == EAGAIN ) {
            return true;
        }

        // Process terminated
        // the exit code will be set in the sigchld event handler
        return false;
    }
}

bool UnixProcessImpl::Write(const wxString& buff)
{
    wxString tmpbuf = buff;
    tmpbuf << wxT("\n");
    int bytes = write(GetWriteHandle(), tmpbuf.mb_str(wxConvUTF8).data(), tmpbuf.Length());
    return bytes == (int)tmpbuf.length();
}

IProcess* UnixProcessImpl::Execute(wxEvtHandler* parent, const wxString& cmd, IProcessCreateFlags flags, const wxString& workingDirectory, IProcessCallback *cb)
{
    wxUnusedVar(flags);

    make_argv(cmd);
    if ( argc == 0 ) {
        return NULL;
    }

    // fork the child process
    wxString curdir = wxGetCwd();

    // Prentend that we are a terminal...
    int master, slave;
    openpty(&master, &slave, NULL, NULL, NULL);

    int rc = fork();
    if ( rc == 0 ) {
        login_tty(slave);
        close(master); // close the un-needed master end

        // at this point, slave is used as stdin/stdout/stderr
        // Child process
        if(workingDirectory.IsEmpty() == false) {
            wxSetWorkingDirectory( workingDirectory );
        }

        // execute the process
        execvp(argv[0], argv);

        // if we got here, we failed...
        exit(0);

    } else if ( rc < 0 ) {
        // Error

        // restore the working directory
        wxSetWorkingDirectory(curdir);

        return NULL;

    } else {
        // Parent
        close(slave);
        freeargv(argv);
        argc = 0;

        // disable ECHO
        struct termios termio;
        tcgetattr(master, &termio);
        termio.c_lflag = ICANON;
        termio.c_oflag = ONOCR | ONLRET;
        tcsetattr(master, TCSANOW, &termio);

        // restore the working directory
        wxSetWorkingDirectory(curdir);

        UnixProcessImpl *proc = new UnixProcessImpl(parent);
        proc->LinkCallback( cb );
        proc->SetReadHandle  (master);
        proc->SetWriteHandler(master);

        proc->SetPid( rc );
        proc->StartReaderThread();
        return proc;
    }
}

void UnixProcessImpl::StartReaderThread()
{
    // Launch the 'Reader' thread
    m_thr = new ProcessReaderThread();
    m_thr->SetProcess( this );
    m_thr->SetNotifyWindow( m_parent );
    m_thr->Start();
}

void UnixProcessImpl::Terminate()
{
    wxKill(GetPid(), GetHardKill() ? wxSIGKILL : wxSIGTERM, NULL, wxKILL_CHILDREN);
    int status(0);
    // The real cleanup is done inside ::ChildTerminatedSingalHandler() signal handler (app.cpp)
    waitpid(-1, &status, WNOHANG);
}

bool UnixProcessImpl::WriteToConsole(const wxString& buff)
{
    wxString tmpbuf = buff;
    tmpbuf.Trim().Trim(false);

    tmpbuf << wxT("\n");
    int bytes = write(GetWriteHandle(), tmpbuf.mb_str(wxConvUTF8).data(), tmpbuf.Length());
    return bytes == (int)tmpbuf.length();
}

#endif //#if defined(__WXMAC )||defined(__WXGTK__)