/*
 * Copyright © 2007 Alistair Crooks.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote
 *    products derived from this software without specific prior written
 *    permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
#include <sys/types.h>
#include <sys/param.h>
#include <sys/stat.h>

#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <fuse.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>

#include "fetch.h"

#include "virtdir.h"
#include "defs.h"

#ifndef DEFAULT_CACHE_DIR
#define DEFAULT_CACHE_DIR       "/tmp"
#endif

static char             *cachedir;      /* location for cached files */

static int               verbose; /* how chatty are we? */

static virtdir_t         ian;

/* retrieve a file from the remote location, and cache it in cachedir */
static int
getfile(const char *url)
{
        struct url_stat  urlstat;
        struct url      *newurlp;
        int64_t          cc;
        char             buf[BUFSIZ * 8];
        char             tmpname[BUFSIZ];
        char             newurl[BUFSIZ];
        char            *cp;
        FILE            *out;
        FILE            *fp;
        int              got;
        int              ret;
        int              fd;

        if ((cp = strchr(url, ':')) == NULL) {
                warn("malformed URL `%s'", url + 1);
                return 0;
        }
        (void) snprintf(newurl, sizeof(newurl), "%.*s/%s", 
                (int)(cp - url), url + 1, cp + 1);
        if ((newurlp = fetchParseURL(newurl)) == NULL) {
                /* add as virtdir */
                virtdir_add(&ian, newurl, strlen(newurl), 'd', "", strlen(""));
                return 1;
        }
        if (newurlp->host[0] == 0x0 || strcmp(newurlp->doc, "/") == 0) {
                virtdir_add(&ian, newurl, strlen(newurl), 'd', "", strlen(""));
                return 1;
        }
        if ((fp = fetchXGetURL(newurl, &urlstat, "p")) == NULL) {
                if (verbose) {
                        warn("Error [%d] \"%s\" \"%s\"\n", fetchLastErrCode, newurl, fetchLastErrString);
                }
                /* XXX - before adding as a directory, we should check it does actually exist */
                virtdir_add(&ian, newurl, strlen(newurl), 'd', "", strlen(""));
                return 1;
        }
        if (verbose) {
                printf("::::::::::\n%s\nSize: %lld\nmtime: %s::::::::::\n",
                        newurl,
                        (long long) urlstat.size,
                        ctime(&urlstat.mtime));
        }
        (void) snprintf(tmpname, sizeof(tmpname), "%s/fetch.XXXXXX", cachedir);
        fd = mkstemp(tmpname);
        if ((out = fdopen(fd, "w")) == NULL) {
                warnx("can't create output file `%s'", tmpname);
                return 0;
        }
        for (ret = 1, cc = 0 ; (got = fread(buf, 1, sizeof(buf), fp)) > 0 ; cc += got) {
                if (fwrite(buf, 1, got, out) != got) {
                        warnx("short write");
                        ret = 0;
                        break;
                }
        }
        (void) fclose(out);
        (void) fclose(fp);
        if (ret) {
                virtdir_add(&ian, newurl, strlen(newurl), 'f', tmpname, strlen(tmpname));
        }
        return ret;
}


/* perform the stat operation */
/* if this is the root, then just synthesise the data */
/* otherwise, retrieve the data, and be sure to fill in the size */
static int 
ian_getattr(const char *path, struct stat *st)
{
        virt_dirent_t   *ep;

        if (strcmp(path, "/") == 0) {
                (void) memset(st, 0x0, sizeof(*st));
                st->st_mode = S_IFDIR | 0755;
                st->st_nlink = 2;
                return 0;
        }
        if ((ep = virtdir_find(&ian, path + 1, strlen(path) - 1)) == NULL) {
                if (!getfile(path)) {
                        return -ENOENT;
                }
                ep = virtdir_find(&ian, path + 1, strlen(path) - 1);
        }
        switch(ep->type) {
        case 'f':
                (void) memcpy(st, &ian.file, sizeof(*st));
                if (stat(ep->tgt, st) < 0) {
                        warn("`%s' has gone", ep->tgt);
                }
                break;
        case 'd':
                (void) memcpy(st, &ian.dir, sizeof(*st));
                break;
        case 'l':
                (void) memcpy(st, &ian.lnk, sizeof(*st));
                st->st_size = ep->tgtlen;
                break;
        }
        return 0;
}

/* readdir operation */
static int 
ian_readdir(const char *path, void *buf, fuse_fill_dir_t filler,
              off_t offset, struct fuse_file_info * fi)
{
        virt_dirent_t   *dp;
        VIRTDIR         *dirp;

        if ((dirp = openvirtdir(&ian, path)) == NULL) {
                return 0;
        }
        filler(buf, ".", NULL, 0);
        filler(buf, "..", NULL, 0);
        while ((dp = readvirtdir(dirp)) != NULL) {
                filler(buf, dp->d_name, NULL, 0);
        }
        closevirtdir(dirp);
        return 0;
}

/* open the file in the file system */
static int 
ian_open(const char *path, struct fuse_file_info * fi)
{
        return 0;
}

/* read the file's contents in the file system */
static int 
ian_read(const char *path, char *buf, size_t size, off_t offset,
           struct fuse_file_info * fi)
{
        virt_dirent_t   *ep;
        int              cc;
        int              fd;

        if ((ep = virtdir_find(&ian, path + 1, strlen(path) - 1)) == NULL) {
                return -ENOENT;
        }
        if ((fd = open(ep->tgt, O_RDONLY, 0666)) < 0) {
                return -EACCES;
        }
        if (lseek(fd, offset, SEEK_SET) < 0) {
                (void) close(fd);
                return -EBADF;
        }
        if ((cc = read(fd, buf, size)) < 0) {
                (void) close(fd);
                return -EBADF;
        }
        (void) close(fd);
        return cc;
}

/* fill in the statvfs struct */
static int
ian_statfs(const char *path, struct statvfs *st)
{
        (void) memset(st, 0x0, sizeof(*st));
        return 0;
}

/* read the symbolic link */
static int
ian_readlink(const char *path, char *buf, size_t size)
{
        virt_dirent_t   *ep;

        if ((ep = virtdir_find(&ian, path, strlen(path))) == NULL) {
                return -ENOENT;
        }
        if (ep->tgt == NULL) {
                return -ENOENT;
        }
        (void) strlcpy(buf, ep->tgt, size);
        return 0;
}

/* operations struct */
static struct fuse_operations ian_oper = {
        .getattr = ian_getattr,
        .readlink = ian_readlink,
        .readdir = ian_readdir,
        .open = ian_open,
        .read = ian_read,
        .statfs = ian_statfs
};

int
main(int argc, char **argv)
{
        int     i;

        cachedir = strdup(DEFAULT_CACHE_DIR);
        while ((i = getopt(argc, argv, "v")) != -1) {
                switch(i) {
                case 'd':
                        (void) free(cachedir);
                        cachedir = strdup(optarg);
                        break;
                case 'v':
                        verbose += 1;
                        break;
                default:
                        warn("unrecognised option `%c'", i);
                        exit(EXIT_FAILURE);
                }
        }
        (void) daemon(1, 1);
        virtdir_add(&ian, "ftp:", strlen("ftp:"), 'd', "", 0);
        virtdir_add(&ian, "http:", strlen("http:"), 'd', "", 0);
        virtdir_add(&ian, "https:", strlen("https:"), 'd', "", 0);
        return fuse_main(argc, argv, &ian_oper, NULL);
}