/* mailstore.c - mail storage backends
 *
 * Copyright © 2009 Carl Worth
 *
 * 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 3 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, see http://www.gnu.org/licenses/ .
 */

#include <stdio.h>
#include <stdarg.h>

#include "notmuch-private.h"

typedef struct _notmuch_mailstore {
    notmuch_status_t (*constructor) (void **data, va_list args);
    FILE *(*open) (struct _notmuch_mailstore *mailstore, const char *filename);
    int (*close) (struct _notmuch_mailstore *mailstore, FILE *);
    int (*rename) (struct _notmuch_mailstore *mailstore, const char *old_filename,
		   const char *new_filename);
    void *data;
} _notmuch_mailstore;

static notmuch_status_t
_maildir_constructor (void **data, unused (va_list ap))
{
    (*data) = NULL;
    return NOTMUCH_STATUS_SUCCESS;
}

static FILE *
_maildir_open_function (unused (notmuch_mailstore_t *mailstore),
			const char *filename)
{
    return fopen (filename, "r");
}

static int
_maildir_close_function (unused (notmuch_mailstore_t *mailstore),
			 FILE *file)
{
    return fclose (file);
}

static int
_maildir_rename_function (unused (notmuch_mailstore_t *mailstore),
			  const char *old_filename, const char *new_filename)
{
    return rename (old_filename, new_filename);
}

/* A mailstore is defined as:
 *
 * - A function used to "open" a mail message. This takes the
 *   "filename" for the file and should return a FILE *.
 *
 * - A function to "rename" a mail message, which is currently only
 *   used in tags_to_maildir_flags.
 *
 * - A "constructor" that creates a mailstore object of the requisite
 *   type. Arguments are passed via va_args.
 *
 * A mailstore also has a "data" field that can be used to store
 * instance-specific information about this mailstore -- for example,
 * a CouchDB URL or a path. FIXME: mailstores are all statically
 * allocated, so maybe we shouldn't do this.
 */
_notmuch_mailstore
notmuch_mailstore_maildir = { _maildir_constructor,
			      _maildir_open_function, _maildir_close_function,
			      _maildir_rename_function,
			      NULL };

_notmuch_mailstore *
notmuch_mailstore_get_by_name (const char *name)
{
    if (strcmp (name, "maildir") == 0)
	return &notmuch_mailstore_maildir;

    return NULL;
}

FILE *
notmuch_mailstore_open (notmuch_mailstore_t *mailstore, const char *filename)
{
    return mailstore->open (mailstore, filename);
}

int
notmuch_mailstore_rename (notmuch_mailstore_t *mailstore, const char *old_filename,
			  const char *new_filename)
{
    return mailstore->rename (mailstore, old_filename, new_filename);
}

int
notmuch_mailstore_close (notmuch_mailstore_t *mailstore, FILE *file)
{
    return mailstore->close (mailstore, file);
}

notmuch_status_t
notmuch_mailstore_construct (notmuch_mailstore_t *mailstore, ...)
{
    va_list va_args;
    notmuch_status_t status;

    va_start (va_args, mailstore);

    status = mailstore->constructor (&mailstore->data, va_args);

    va_end (va_args);
    return status;
}