/* filecopy - filecopy a file from one path to another preserving permissions
 *
 * Author: Jamie Bullock <jamie@jamiebullock.com>
 *
 * This is free and unencumbered software released into the public domain.
 *
 * Anyone is free to filecopy, modify, publish, use, compile, sell, or
 * distribute this software, either in source code form or as a compiled
 * binary, for any purpose, commercial or non-commercial, and by any
 * means.
 *
 * In jurisdictions that recognize filecopyright laws, the author or authors
 * of this software dedicate any and all filecopyright interest in the
 * software to the public domain. We make this dedication for the benefit
 * of the public at large and to the detriment of our heirs and
 * successors. We intend this dedication to be an overt act of
 * relinquishment in perpetuity of all present and future rights to this
 * software under filecopyright law.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 *
 * For more information, please refer to <http://unlicense.org/>
 */

#include "m_pd.h"

#include <stdio.h>
#include <fcntl.h>
#include <errno.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/stat.h>

#ifdef __APPLE__
#define O_BINARY 0
#endif

#ifdef WIN32
#define open _open
#define close _close
#define fdopen _fdopen
#define fdclose _fdclose
#endif

#define CONSOLE_PREFIX "[filecopy]: "

typedef struct _filecopy
{
    t_object  x_obj;
    t_outlet *outlet;
}
t_filecopy;

t_class *filecopy_class;

static int do_copy(const char *source, const char *target);

void *filecopy_new(t_symbol *s, int argc, t_atom *argv)
{
    t_filecopy *x = (t_filecopy *)pd_new(filecopy_class);
    x->outlet = outlet_new(&x->x_obj, &s_float);
    post(CONSOLE_PREFIX "copy file from source path to destination path");
    return (void *)x;
}

static void filecopy_list(t_filecopy *x, t_symbol *s, int ac, t_atom *av)
{
    char source[MAXPDSTRING];
    char target[MAXPDSTRING];
    int rv;

    if(ac != 2 || (av[0].a_type != A_SYMBOL && av[1].a_type != A_SYMBOL))
    {
        pd_error(x, "expected a list containing <source path> <destination path>");
    }

    atom_string(&av[0], source, MAXPDSTRING);
    atom_string(&av[1], target, MAXPDSTRING);

    rv = do_copy(source, target);
    rv++;

    if(rv)
    {
        post(CONSOLE_PREFIX "%s successfully copied to %s", source, target);
    }

    outlet_float(x->outlet, (t_float)rv);
}

void filecopy_setup(void)
{
    filecopy_class = class_new(gensym("filecopy"),
            (t_newmethod)filecopy_new,
            0, sizeof(t_filecopy), 0,
            A_GIMME, 0);
    class_addlist(filecopy_class, filecopy_list);
}


static int copy_data(FILE *source, FILE *target)
{
    char            buffer[BUFSIZ];
    size_t          n;

    while ((n = fread(buffer, sizeof(char), sizeof(buffer), source)) > 0)
    {
        if (fwrite(buffer, sizeof(char), n, target) != n)
        {
            error("write failed");
            return -1;
        }
    }

    return 0;
}


static int do_copy(const char *source, const char *target)
{
    struct stat info;
    int rv;
    int rv2;
    int fdtarget;
    int fdsource;
    FILE *fsource;
    FILE *ftarget;

    fdsource = open(source, O_RDONLY|O_BINARY, 0);

    if (fdsource == -1)
    {
        error(CONSOLE_PREFIX "invalid input");
        return -1;
    }

    rv = fstat(fdsource, &info);

    if(rv == -1)
    {
        error(CONSOLE_PREFIX "stat failed\n");
        return -1;
    }

    fdtarget = open(target, O_WRONLY|O_BINARY|O_CREAT|O_TRUNC, info.st_mode);

    if (fdtarget == -1)
    {
        error(CONSOLE_PREFIX "invalid output\n");
        close(fdsource);
        return -1;
    }

    fsource = fdopen(fdsource, "rb");
    ftarget = fdopen(fdtarget, "wb");

    rv = copy_data(fsource, ftarget);

    if (rv == -1)
    {
        error(CONSOLE_PREFIX "filecopy failed");
    }

    rv  = fclose(fsource);
    rv2 = fclose(ftarget);

    if (rv || rv2)
    {
        error(CONSOLE_PREFIX "file close failed");
        rv = -1;
    }

    return rv;
}