/*
 * Copyright (c) 1990,1993 Regents of The University of Michigan.
 * All Rights Reserved.  See COPYRIGHT.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif /* HAVE_CONFIG_H */

#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/file.h>
#include <sys/param.h>

#include <atalk/adouble.h>
#include <atalk/afp.h>
#include <atalk/bstradd.h>
#include <atalk/bstrlib.h>
#include <atalk/cnid.h>
#include <atalk/globals.h>
#include <atalk/logger.h>
#include <atalk/netatalk_conf.h>
#include <atalk/util.h>
#include <atalk/vfs.h>

#include "desktop.h"
#include "dircache.h"
#include "directory.h"
#include "file.h"
#include "filedir.h"
#include "fork.h"
#include "volume.h"

#define min(a,b)	((a)<(b)?(a):(b))

/*
 * Struct to save directory reading context in. Used to prevent
 * O(n^2) searches on a directory.
 */
struct savedir {
    u_short	 sd_vid;
    uint32_t	 sd_did;
    int		 sd_buflen;
    char	 *sd_buf;
    char	 *sd_last;
    unsigned int sd_sindex;
};
#define SDBUFBRK	2048

static int enumerate_loop(struct dirent *de, char *mname _U_, void *data)
{
    struct savedir *sd = data;
    char *start, *end;
    int  len,lenm;

    end = sd->sd_buf + sd->sd_buflen;
    len = strlen(de->d_name);
    *(sd->sd_last)++ = len;
    lenm = 0; /* strlen(mname);*/
    if ( sd->sd_last + len +lenm + 4 > end ) {
        char *buf;

        start = sd->sd_buf;
        if (!(buf = realloc( sd->sd_buf, sd->sd_buflen +SDBUFBRK )) ) {
            LOG(log_error, logtype_afpd, "afp_enumerate: realloc: %s",
                        strerror(errno) );
            errno = ENOMEM;
            return -1;
        }
        sd->sd_buf = buf;
        sd->sd_buflen += SDBUFBRK;
        sd->sd_last = ( sd->sd_last - start ) + sd->sd_buf;
        end = sd->sd_buf + sd->sd_buflen;
    }

    memcpy( sd->sd_last, de->d_name, len + 1 );
    sd->sd_last += len + 1;
    return 0;
}

/* -----------------------------
 * FIXME:
 * Doesn't work with dangling symlink
 * i.e.:
 * - Move a folder with a dangling symlink in the trash
 * - empty the trash
 * afp_enumerate return an empty listing but offspring count != 0 in afp_getdirparams
 * and the Mac doesn't try to call afp_delete!
 *
 * Another option for symlink
 * cf:
 * http://sourceforge.net/tracker/index.php?func=detail&aid=461938&group_id=8642&atid=108642
 *
*/
char *check_dirent(const struct vol *vol, char *name)
{
    if (!strcmp(name, "..") || !strcmp(name, "."))
        return NULL;

    if (!vol->vfs->vfs_validupath(vol, name))
        return NULL;

    /* check for vetoed filenames */
    if (veto_file(vol->v_veto, name))
        return NULL;

#if 0
    char *m_name = NULL;

    if (NULL == (m_name = utompath(vol, name, 0, utf8_encoding())))
        return NULL;

    /* now check against too big a file */
    if (strlen(m_name) > vol->max_filename)
        return NULL;
#endif
    return name;
}

/* ----------------------------- */
int
for_each_dirent(const struct vol *vol, char *name, dir_loop fn, void *data)
{
    DIR             *dp;
    struct dirent	*de;
    char            *m_name;
    int             ret;

    if (NULL == ( dp = opendir( name)) ) {
        return -1;
    }
    ret = 0;
    for ( de = readdir( dp ); de != NULL; de = readdir( dp )) {
        if (!(m_name = check_dirent(vol, de->d_name)))
            continue;

        ret++;
        if (fn && fn(de,m_name, data) < 0) {
           closedir(dp);
           return -1;
        }
    }
    closedir(dp);
    return ret;
}

/* This is the maximal length of a single entry for a file/dir in the reply
   block if all bits in the file/dir bitmap are set: header(4) + params(104) +
   macnamelength(1) + macname(31) + utf8(4) + utf8namelen(2) + utf8name(255) +
   oddpadding(1) */

#define REPLY_PARAM_MAXLEN (4 + 104 + 1 + MACFILELEN + 4 + 2 + UTF8FILELEN_EARLY + 1)

/* ----------------------------- */
static int enumerate(AFPObj *obj _U_, char *ibuf, size_t ibuflen _U_,
    char *rbuf,
    size_t *rbuflen,
    int ext)
{
    static struct savedir	sd = { 0, 0, 0, NULL, NULL, 0 };
    struct vol			*vol;
    struct dir			*dir;
    int				did, ret, len, first = 1;
    size_t			esz;
    char                        *data, *start;
    uint16_t			vid, fbitmap, dbitmap, reqcnt, actcnt = 0;
    uint16_t			temp16;
    uint32_t			sindex, maxsz, sz = 0;
    struct path                 *o_path;
    struct path                 s_path;
    int                         header;

    if ( sd.sd_buflen == 0 ) {
        if (( sd.sd_buf = (char *)malloc( SDBUFBRK )) == NULL ) {
            LOG(log_error, logtype_afpd, "afp_enumerate: malloc: %s", strerror(errno) );
            *rbuflen = 0;
            return AFPERR_MISC;
        }
        sd.sd_buflen = SDBUFBRK;
    }

    ibuf += 2;

    memcpy( &vid, ibuf, sizeof( vid ));
    ibuf += sizeof( vid );

    if (NULL == ( vol = getvolbyvid( vid )) ) {
        *rbuflen = 0;
        return( AFPERR_PARAM );
    }

    memcpy( &did, ibuf, sizeof( did ));
    ibuf += sizeof( did );

    if (NULL == ( dir = dirlookup( vol, did )) ) {
        *rbuflen = 0;
        return (afp_errno == AFPERR_NOOBJ)?AFPERR_NODIR:afp_errno;
    }

    memcpy( &fbitmap, ibuf, sizeof( fbitmap ));
    fbitmap = ntohs( fbitmap );
    ibuf += sizeof( fbitmap );

    memcpy( &dbitmap, ibuf, sizeof( dbitmap ));
    dbitmap = ntohs( dbitmap );
    ibuf += sizeof( dbitmap );

    /* check for proper bitmaps -- the stuff in comments is for
     * variable directory ids. */
    if (!(fbitmap || dbitmap)
            /*|| (fbitmap & (1 << FILPBIT_PDID)) ||
              (dbitmap & (1 << DIRPBIT_PDID))*/) {
        *rbuflen = 0;
        return AFPERR_BITMAP;
    }

    memcpy( &reqcnt, ibuf, sizeof( reqcnt ));
    reqcnt = ntohs( reqcnt );
    ibuf += sizeof( reqcnt );

    if (ext == 2) {
        memcpy( &sindex, ibuf, sizeof( sindex ));
        sindex = ntohl( sindex );
        ibuf += sizeof( sindex );
    }
    else {
        memcpy( &temp16, ibuf, sizeof( temp16 ));
        sindex = ntohs( temp16 );
        ibuf += sizeof( temp16 );
    }

    if (!sindex) {
        *rbuflen = 0;
        return AFPERR_PARAM ;
    }

    if (ext == 2) {
        memcpy( &maxsz, ibuf, sizeof( maxsz ));
        maxsz = ntohl( maxsz );
        ibuf += sizeof( maxsz );
    }
    else {
        memcpy( &temp16, ibuf, sizeof( temp16 ));
        maxsz = ntohs( temp16 );
        ibuf += sizeof( temp16 );
    }

    header = (ext)?4:2;
    header *=sizeof( uint8_t );

    maxsz = min(maxsz, *rbuflen - REPLY_PARAM_MAXLEN);
    o_path = cname( vol, dir, &ibuf );

    if (afp_errno == AFPERR_NOOBJ)
        afp_errno = AFPERR_NODIR;

    *rbuflen = 0;
    if (NULL == o_path ) {
        return get_afp_errno(AFPERR_NOOBJ);
    }
    if ( *o_path->m_name != '\0') {
        /* it's a file or it's a dir and extendir() was unable to chdir in it */
        return path_error(o_path, AFPERR_NODIR );
    }

    LOG(log_debug, logtype_afpd, "enumerate(\"%s/%s\", f/d:%04x/%04x, rc:%u, i:%u, max:%u)",
        getcwdpath(), o_path->u_name, fbitmap, dbitmap, reqcnt, sindex, maxsz);

    data = rbuf + 3 * sizeof( uint16_t );
    sz = 3 * sizeof( uint16_t );	/* fbitmap, dbitmap, reqcount */

    /*
     * Read the directory into a pre-malloced buffer, stored
     *		len <name> \0
     * The end is indicated by a len of 0.
     */
    if ( sindex == 1 || curdir->d_did != sd.sd_did || vid != sd.sd_vid ) {
        sd.sd_last = sd.sd_buf;
        /* if dir was in the cache we don't have the inode */
        if (( !o_path->st_valid && ostat(".", &o_path->st, vol_syml_opt(vol)) < 0 ) ||
            (ret = for_each_dirent(vol, ".", enumerate_loop, (void *)&sd)) < 0)
        {
            LOG(log_error, logtype_afpd, "enumerate: loop error: %s (%d)", strerror(errno), errno);
            switch (errno) {
            case EACCES:
                return AFPERR_ACCESS;
            case ENOTDIR:
                return AFPERR_BADTYPE;
            case ENOMEM:
                return AFPERR_MISC;
            default:
                return AFPERR_NODIR;
            }
        }
        setdiroffcnt(curdir, &o_path->st,  ret);
        *sd.sd_last = 0;

        sd.sd_last = sd.sd_buf;
        sd.sd_sindex = 1;

        sd.sd_vid = vid;
        sd.sd_did = curdir->d_did;
    }

    /*
     * Position sd_last as dictated by sindex.
     */
    if ( sindex < sd.sd_sindex ) {
        sd.sd_sindex = 1;
        sd.sd_last = sd.sd_buf;
    }
    while ( sd.sd_sindex < sindex ) {
        len = (unsigned char)*(sd.sd_last)++;
        if ( len == 0 ) {
            sd.sd_did = 0;	/* invalidate sd struct to force re-read */
            return( AFPERR_NOOBJ );
        }
        sd.sd_last += len + 1;
        sd.sd_sindex++;
    }

    while (( len = (unsigned char)*(sd.sd_last)) != 0 ) {
        /*
         * If we've got all we need, send it.
         */
        if ( actcnt == reqcnt ) {
            break;
        }

        /*
         * Save the start position, in case we exceed the buffer
         * limitation, and have to back up one.
         */
        start = sd.sd_last;
        sd.sd_last++;

        if (*sd.sd_last == 0) {
            /* stat() already failed on this one */
            sd.sd_last += len + 1;
            continue;
        }

        memset(&s_path, 0, sizeof(s_path));
        s_path.u_name = sd.sd_last;
        if (of_stat(vol, &s_path) < 0 ) {
            /* so the next time it won't try to stat it again
             * another solution would be to invalidate the cache with
             * sd.sd_did = 0 but if it's not ENOENT error it will start again
             */
            *sd.sd_last = 0;
            sd.sd_last += len + 1;
            curdir->d_offcnt--;		/* a little lie */
            continue;
        }

        /* conversions on the fly */
        const char *convname;
        if (ad_convert(sd.sd_last, &s_path.st, vol, &convname) == 0) {
            if (convname) {
                s_path.u_name = (char *)convname;
                AFP_CNID_START("cnid_lookup");
                s_path.id = cnid_lookup(vol->v_cdb, &s_path.st, curdir->d_did, sd.sd_last, strlen(sd.sd_last));
                AFP_CNID_DONE();
                if (s_path.id != CNID_INVALID) {
                    AFP_CNID_START("cnid_update");
                    int cnid_up_ret = cnid_update(vol->v_cdb, s_path.id, &s_path.st, curdir->d_did, (char *)convname, strlen(convname));
                    AFP_CNID_DONE();
                    if (cnid_up_ret != 0)
                        LOG(log_error, logtype_afpd, "enumerate: error updating CNID of \"%s\"", fullpathname(convname));
                }
            }
        }

        sd.sd_last += len + 1;
        s_path.m_name = NULL;

        /*
         * If a fil/dir is not a dir, it's a file. This is slightly
         * inaccurate, since that means /dev/null is a file, /dev/printer
         * is a file, etc.
         */
        if ( S_ISDIR(s_path.st.st_mode)) {
            if ( dbitmap == 0 ) {
                continue;
            }
            int len = strlen(s_path.u_name);
            if ((dir = dircache_search_by_name(vol, curdir, s_path.u_name, len)) == NULL) {
                if ((dir = dir_add(vol, curdir, &s_path, len)) == NULL) {
                    LOG(log_error, logtype_afpd, "enumerate(vid:%u, did:%u, name:'%s'): error adding dir: '%s'",
                        ntohs(vid), ntohl(did), o_path->u_name, s_path.u_name);
                    return AFPERR_MISC;
                }
            }
            if ((ret = getdirparams(obj, vol, dbitmap, &s_path, dir, data + header , &esz)) != AFP_OK)
                return( ret );

        } else {
            if ( fbitmap == 0 ) {
                continue;
            }
            /* files are added to the dircache in getfilparams() -> getmetadata() */
            if (AFP_OK != ( ret = getfilparams(obj, vol, fbitmap, &s_path, curdir,
                                               data + header, &esz, 1)) ) {
                return( ret );
            }
        }

        /*
         * Make sure entry is an even length, possibly with a null
         * byte on the end.
         */
        if ( (esz + header) & 1 ) {
            *(data + header + esz ) = '\0';
            esz++;
        }

        /*
         * Check if we've exceeded the size limit.
         */
        if ( maxsz < sz + esz + header) {
            if (first) { /* maxsz can't hold a single reply */
                return AFPERR_PARAM;
            }
            sd.sd_last = start;
            break;
        }

        if (first)
            first = 0;

        sz += esz + header;
        if (ext) {
            temp16 = htons( esz + header );
            memcpy( data, &temp16, sizeof( temp16 ));
            data += sizeof(temp16);
        }
        else {
            *data++ = esz + header;
        }

        *data++ = S_ISDIR(s_path.st.st_mode) ? FILDIRBIT_ISDIR : FILDIRBIT_ISFILE;
        if (ext) {
             *data++ = 0;
        }
        data += esz;
        actcnt++;
        /* FIXME if we rollover 16 bits and it's not FPEnumerateExt2 */
    }

    if ( actcnt == 0 ) {
        sd.sd_did = 0;		/* invalidate sd struct to force re-read */
        /*
         * in case were converting adouble stuff:
         * after enumerating the whole dir we should have converted everything
         * thus the .AppleDouble dir shouls be empty thus we can no try to
         * delete it
         */
        if (vol->v_adouble == AD_VERSION_EA && ! (vol->v_flags & AFPVOL_NOV2TOEACONV))
            (void)rmdir(".AppleDouble");

        return( AFPERR_NOOBJ );
    }
    sd.sd_sindex = sindex + actcnt;

    /*
     * All done, fill in misc junk in rbuf
     */
    fbitmap = htons( fbitmap );
    memcpy( rbuf, &fbitmap, sizeof( fbitmap ));
    rbuf += sizeof( fbitmap );
    dbitmap = htons( dbitmap );
    memcpy( rbuf, &dbitmap, sizeof( dbitmap ));
    rbuf += sizeof( dbitmap );
    actcnt = htons( actcnt );
    memcpy( rbuf, &actcnt, sizeof( actcnt ));
    rbuf += sizeof( actcnt );
    *rbuflen = sz;
    return( AFP_OK );
}

/* ----------------------------- */
int afp_enumerate(AFPObj *obj, char *ibuf, size_t ibuflen,
    char *rbuf,
    size_t *rbuflen)
{
    return enumerate(obj, ibuf,ibuflen ,rbuf,rbuflen , 0);
}

/* ----------------------------- */
int afp_enumerate_ext(AFPObj *obj, char *ibuf, size_t ibuflen,
    char *rbuf,
    size_t *rbuflen)
{
    return enumerate(obj, ibuf,ibuflen ,rbuf,rbuflen , 1);
}

/* ----------------------------- */
int afp_enumerate_ext2(AFPObj *obj, char *ibuf, size_t ibuflen,
    char *rbuf,
    size_t *rbuflen)
{
    return enumerate(obj, ibuf,ibuflen ,rbuf,rbuflen , 2);
}
