/*****************************************************************************
 * directory.c: expands a directory (directory: access plug-in)
 *****************************************************************************
 * Copyright (C) 2002-2008 the VideoLAN team
 * $Id: 03d8df0f81e2c1b88582ffa8cf1e1b354cdbd250 $
 *
 * Authors: Derk-Jan Hartman <hartman at videolan dot org>
 *          Rémi Denis-Courmont
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
 *****************************************************************************/

/*****************************************************************************
 * Preamble
 *****************************************************************************/

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

#include <vlc_common.h>
#include <vlc_plugin.h>
#include <vlc_access.h>

#ifdef HAVE_SYS_TYPES_H
#   include <sys/types.h>
#endif
#ifdef HAVE_SYS_STAT_H
#   include <sys/stat.h>
#endif

#ifdef HAVE_UNISTD_H
#   include <unistd.h>
#elif defined( WIN32 ) && !defined( UNDER_CE )
#   include <io.h>
#endif

#ifdef HAVE_DIRENT_H
#   include <dirent.h>
#endif

#include <vlc_charset.h>
#include <vlc_url.h>

/*****************************************************************************
 * Module descriptor
 *****************************************************************************/
static int  Open ( vlc_object_t * );
static void Close( vlc_object_t * );

#define RECURSIVE_TEXT N_("Subdirectory behavior")
#define RECURSIVE_LONGTEXT N_( \
        "Select whether subdirectories must be expanded.\n" \
        "none: subdirectories do not appear in the playlist.\n" \
        "collapse: subdirectories appear but are expanded on first play.\n" \
        "expand: all subdirectories are expanded.\n" )

static const char *const psz_recursive_list[] = { "none", "collapse", "expand" };
static const char *const psz_recursive_list_text[] = {
    N_("none"), N_("collapse"), N_("expand") };

#define IGNORE_TEXT N_("Ignored extensions")
#define IGNORE_LONGTEXT N_( \
        "Files with these extensions will not be added to playlist when " \
        "opening a directory.\n" \
        "This is useful if you add directories that contain playlist files " \
        "for instance. Use a comma-separated list of extensions." )

vlc_module_begin();
    set_category( CAT_INPUT );
    set_shortname( N_("Directory" ) );
    set_subcategory( SUBCAT_INPUT_ACCESS );
    set_description( N_("Standard filesystem directory input") );
    set_capability( "access", 55 );
    add_shortcut( "directory" );
    add_shortcut( "dir" );
    add_shortcut( "file" );
    add_string( "recursive", "expand" , NULL, RECURSIVE_TEXT,
                RECURSIVE_LONGTEXT, false );
      change_string_list( psz_recursive_list, psz_recursive_list_text, 0 );
    add_string( "ignore-filetypes", "m3u,db,nfo,jpg,gif,sfv,txt,sub,idx,srt,cue",
                NULL, IGNORE_TEXT, IGNORE_LONGTEXT, false );
    set_callbacks( Open, Close );
vlc_module_end();


/*****************************************************************************
 * Local prototypes, constants, structures
 *****************************************************************************/

enum
{
    MODE_EXPAND,
    MODE_COLLAPSE,
    MODE_NONE
};

typedef struct directory_t directory_t;
struct directory_t
{
    directory_t *parent;
    DIR         *handle;
    char        *uri;
#ifndef WIN32
    struct stat  st;
#endif
    char         path[1];
};

struct access_sys_t
{
    directory_t *current;
    DIR *handle;
    char *ignored_exts;
    int mode;
};

static block_t *Block( access_t * );
static int Control( access_t *, int, va_list );

/*****************************************************************************
 * Open: open the directory
 *****************************************************************************/
static int Open( vlc_object_t *p_this )
{
    access_t *p_access = (access_t*)p_this;
    access_sys_t *p_sys;

    if( !p_access->psz_path )
        return VLC_EGENERIC;

    DIR *handle = utf8_opendir (p_access->psz_path);
    if (handle == NULL)
        return VLC_EGENERIC;

    p_sys = malloc (sizeof (*p_sys));
    if (!p_sys)
        return VLC_ENOMEM;

    p_access->p_sys = p_sys;
    p_sys->current = NULL;
    p_sys->handle = handle;
    p_sys->ignored_exts = var_CreateGetString (p_access, "ignore-filetypes");

    /* Handle mode */
    char *psz = var_CreateGetString( p_access, "recursive" );
    if( *psz == '\0' || !strcasecmp( psz, "none" )  )
        p_sys->mode = MODE_NONE;
    else if( !strcasecmp( psz, "collapse" )  )
        p_sys->mode = MODE_COLLAPSE;
    else
        p_sys->mode = MODE_EXPAND;
    free( psz );

    p_access->pf_read  = NULL;
    p_access->pf_block = Block;
    p_access->pf_seek  = NULL;
    p_access->pf_control= Control;
    free (p_access->psz_demux);
    p_access->psz_demux = strdup ("xspf-open");

    return VLC_SUCCESS;
}

/*****************************************************************************
 * Close: close the target
 *****************************************************************************/
static void Close( vlc_object_t * p_this )
{
    access_t *p_access = (access_t*)p_this;
    access_sys_t *p_sys = p_access->p_sys;

    while (p_sys->current)
    {
        directory_t *current = p_sys->current;

        p_sys->current = current->parent;
        closedir (current->handle);
        free (current->uri);
        free (current);
    }
    if (p_sys->handle != NULL)
        closedir (p_sys->handle); /* corner case,:Block() not called ever */
    free (p_sys->ignored_exts);
    free (p_sys);
}

/**
 * URI-encodes a file path. The only reserved characters is slash.
 */
static char *encode_path (const char *path)
{
    static const char sep[]= "%2F";
    char *enc = encode_URI_component (path), *ptr = enc;

    if (enc == NULL)
        return NULL;

    /* Replace '%2F' with '/'. TODO: extend encode_URI*() */
    /* (On Windows, both ':' and '\\' will be encoded) */
    while ((ptr = strstr (ptr, sep)) != NULL)
    {
        *ptr++ = '/';
        memmove (ptr, ptr + 2, strlen (ptr) - 1);
    }
    return enc;
}

/* Detect directories that recurse into themselves. */
static bool has_inode_loop (const directory_t *dir)
{
#ifndef WIN32
    dev_t dev = dir->st.st_dev;
    ino_t inode = dir->st.st_ino;

    while ((dir = dir->parent) != NULL)
        if ((dir->st.st_dev == dev) && (dir->st.st_ino == inode))
            return true;
#else
# define fstat( fd, st ) (0)
#endif
    return false;
}

static block_t *Block (access_t *p_access)
{
    access_sys_t *p_sys = p_access->p_sys;
    directory_t *current = p_sys->current;

    if (p_access->info.b_eof)
        return NULL;

    if (current == NULL)
    {   /* Startup: send the XSPF header */
        static const char header[] =
            "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n"
            "<playlist version=\"1\" xmlns=\"http://xspf.org/ns/0/\">\n"
            " <trackList>\n";
        block_t *block = block_Alloc (sizeof (header) - 1);
        if (!block)
            goto fatal;
        memcpy (block->p_buffer, header, sizeof (header) - 1);

        /* "Open" the base directory */
        current = malloc (sizeof (*current) + strlen (p_access->psz_path));
        if (current == NULL)
        {
            block_Release (block);
            goto fatal;
        }
        current->parent = NULL;
        current->handle = p_sys->handle;
        strcpy (current->path, p_access->psz_path);
        current->uri = encode_path (current->path);
        if ((current->uri == NULL)
         || fstat (dirfd (current->handle), &current->st))
        {
            free (current->uri);
            free (current);
            block_Release (block);
            goto fatal;
        }

        p_sys->handle = NULL;
        p_sys->current = current;
        return block;
    }

    char *entry = utf8_readdir (current->handle);
    if (entry == NULL)
    {   /* End of directory, go back to parent */
        closedir (current->handle);
        p_sys->current = current->parent;
        free (current);

        if (p_sys->current == NULL)
        {   /* End of XSPF playlist */
            static const char footer[] =
                " </trackList>\n"
                "</playlist>\n";

            block_t *block = block_Alloc (sizeof (footer) - 1);
            if (!block)
                goto fatal;
            memcpy (block->p_buffer, footer, sizeof (footer) - 1);
            p_access->info.b_eof = true;
            return block;
        }
        return NULL;
    }

    /* Skip current and parent directories */
    if (!strcmp (entry, ".") || !strcmp (entry, ".."))
        return NULL;
    /* Handle recursion */
    if (p_sys->mode != MODE_COLLAPSE)
    {
        directory_t *sub = malloc (sizeof (*sub) + strlen (current->path) + 1
                                                 + strlen (entry));
        if (sub == NULL)
            return NULL;
        sprintf (sub->path, "%s/%s", current->path, entry);

        DIR *handle = utf8_opendir (sub->path);
        if (handle != NULL)
        {
            sub->parent = current;
            sub->handle = handle;
            sub->uri = encode_path (sub->path);

            if ((p_sys->mode == MODE_NONE)
             || fstat (dirfd (handle), &sub->st)
             || has_inode_loop (sub)
             || (sub->uri == NULL))
            {
                closedir (handle);
                free (sub);
                return NULL;
            }
            p_sys->current = sub;
            return NULL;
        }
        else
            free (sub);
    }

    /* Skip files with ignored extensions */
    if (p_sys->ignored_exts != NULL)
    {
        const char *ext = strrchr (entry, '.');
        if (ext != NULL)
        {
            size_t extlen = strlen (++ext);
            for (const char *type = p_sys->ignored_exts, *end;
                 type[0]; type = end + 1)
            {
                end = strchr (type, ',');
                if (end == NULL)
                    end = type + strlen (type);

                if (type + extlen == end
                 && !strncasecmp (ext, type, extlen))
                    return NULL;
            }
        }
    }

    char *encoded = encode_URI_component (entry);
    free (entry);
    if (encoded == NULL)
        goto fatal;
    int len = asprintf (&entry,
                        "  <track><location>file://%s/%s</location></track>\n",
                        current->uri, encoded);
    free (encoded);
    if (len == -1)
        goto fatal;

    /* TODO: new block allocator for malloc()ated data */
    block_t *block = block_Alloc (len);
    if (!block)
    {
        free (entry);
        goto fatal;
    }
    memcpy (block->p_buffer, entry, len);
    free (entry);
    return block;

fatal:
    p_access->info.b_eof = true;
    return NULL;
}

/*****************************************************************************
 * Control:
 *****************************************************************************/
static int Control( access_t *p_access, int i_query, va_list args )
{
    bool   *pb_bool;
    int          *pi_int;
    int64_t      *pi_64;

    switch( i_query )
    {
        /* */
        case ACCESS_CAN_SEEK:
        case ACCESS_CAN_FASTSEEK:
            pb_bool = (bool*)va_arg( args, bool* );
            *pb_bool = false;
            break;

        case ACCESS_CAN_PAUSE:
        case ACCESS_CAN_CONTROL_PACE:
            pb_bool = (bool*)va_arg( args, bool* );
            *pb_bool = true;
            break;

        /* */
        case ACCESS_GET_MTU:
            pi_int = (int*)va_arg( args, int * );
            *pi_int = 0;
            break;

        case ACCESS_GET_PTS_DELAY:
            pi_64 = (int64_t*)va_arg( args, int64_t * );
            *pi_64 = DEFAULT_PTS_DELAY * 1000;
            break;

        /* */
        case ACCESS_SET_PAUSE_STATE:
        case ACCESS_GET_TITLE_INFO:
        case ACCESS_SET_TITLE:
        case ACCESS_SET_SEEKPOINT:
        case ACCESS_SET_PRIVATE_ID_STATE:
        case ACCESS_GET_CONTENT_TYPE:
        case ACCESS_GET_META:
            return VLC_EGENERIC;

        default:
            msg_Warn( p_access, "unimplemented query in control" );
            return VLC_EGENERIC;
    }
    return VLC_SUCCESS;
}
