#include <stdlib.h>

#include <unistd.h>

#include <assert.h>

#include <errno.h>

#include <sys/select.h>

#include "main.h"

#include "filter.h"

#include "handlers.h"

/* it uses app_stdin, app_stdout, app_stderr.

 * They have value -1 if not opened. */

static struct FilterRules *fr;

void write_newline_cb(struct FilterRules *myfr,

        const struct FFilter *ff, char *obuf, int *olen,

        const char *ibuf, int pos)

{

    obuf[(*olen)++] = '\n';

}

void app_control_start()

{

    struct FFilter *ff;

    fr = new_filter_rules();

    /* We don't pay attention to any telnet command */

    ff = new_ftelnet();

    add_ffilter(fr, ff);

    /* The client will send \r\0 on enter */

    ff = new_fstring_len("\r\0", 2);

    ff->callback = write_newline_cb;

    add_ffilter(fr, ff);

    /* We should trim the no operation characters '\0'.

     * We rely on the filter application order. First \r\0 above,

     * then \0. */

    ff = new_fstring_len("\0", 1);

    add_ffilter(fr, ff);

}

void app_control_shutdown()

{

}

void app_control_prepare_read_fdset(fd_set *read_set, int *maxfd)

{

    assert(app_stdout != -1 || app_stderr != -1);

    if (app_stdout != -1)

    {

        FD_SET(app_stdout, read_set);

        *maxfd = max(*maxfd, app_stdout);

    }

    if (app_stderr != -1 && app_stdout != app_stderr)

    {

        FD_SET(app_stderr, read_set);

        *maxfd = max(*maxfd, app_stderr);

    }

}

/* Return -1, finished stdout/stderr. Else, return 0. */

int app_control_process_read_fdset(fd_set *read_set)

{

    if (app_stdout != -1 && FD_ISSET(app_stdout, read_set))

    {

        int res;

        res = read(app_stdout, stream_buffer, stream_buffer_size);

        if (res == -1 && errno == EIO)

        {

            /* I've noticed that when the app dies, read() returns EIO */

            app_stdout = -1;

            app_stdin = -1;

            return -1;

        }

        if (res == -1 )

            error("Error reading from app.");

        if (res == 0)

        {

            close(app_stdout);

            close(1); /* MOVE */

            app_stdout = -1;

            if (app_stdout == app_stderr || app_stderr == -1)

                return -1;

        } else

        {

            /* MOVE */

            hex_dump("from app", stream_buffer, res);

            write(1, stream_buffer, res);

            if (command_line.s_param.serve_unix)

                s_unix_send_to_connected(stream_buffer, res);

            if (command_line.s_param.serve_tcp)

                s_tcp_send_to_connected(stream_buffer, res);

        }

    }

    if (app_stderr != -1 && app_stdout != app_stderr &&

            FD_ISSET(app_stderr, read_set))

    {

        int res;

        res = read(app_stderr, stream_buffer, stream_buffer_size);

        if (res == 0)

        {

            close(app_stderr);

            close(2); /* MOVE */

            app_stderr = -1;

            if (app_stdout == -1)

                return -1;

        } else

        {

            /* MOVE */

            write(2, stream_buffer, res);

            if (command_line.s_param.serve_unix)

                s_unix_send_to_connected(stream_buffer, res);

            if (command_line.s_param.serve_tcp)

                s_tcp_send_to_connected(stream_buffer, res);

        }

    }

    return 0;

}

void app_control_local_send_to_stdin(const char *buffer, size_t size)

{

    if (size == 0)

        close(app_stdin);

    else

    {

        hex_dump("from local to app", buffer, size);

        write(app_stdin, buffer, size);

    }

}

static void write_data_to_app_stdin(const char *buffer, size_t size)

{

    if (size > 0)

    {

        hex_dump("to app", buffer, size);

        if(command_line.s_param.echo_in_local_terminal)

            write(1, buffer, size);

        write(app_stdin, buffer, size);

    }

}

void app_control_remote_send_to_stdin(const char *buffer, size_t size)

{

    hex_dump("from client prefilter", buffer, size);

    if (command_line.s_param.client_can_write)

    {

        int osize;

        if (size > 0)

        {

            filter_stream(fr, ostream_buffer, &osize,

                    buffer, size);

            if (osize > 0)

                write_data_to_app_stdin(ostream_buffer, osize);

        } else if (size == 0)

        {

            filter_flush(fr, ostream_buffer, &osize);

            if (osize > 0)

                write_data_to_app_stdin(ostream_buffer, osize);

        }

        if (size == 0 && command_line.s_param.client_may_close_app_stdin)

            close(app_stdin);

    }

}