/*
 * Copyright (C) 2006-2009 Andre Noll <maan@systemlinux.org>
 *
 * Licensed under the GPL v2. For licencing details see COPYING.
 */

/** \file file_write.c simple output plugin for testing purposes */

#include <sys/types.h>
#include <dirent.h>

#include "para.h"
#include "list.h"
#include "sched.h"
#include "ggo.h"
#include "write.h"
#include "string.h"
#include "fd.h"
#include "file_write.cmdline.h"
#include "error.h"

/** data specific to the file writer */
struct private_file_write_data {
	/** the file descriptor of the output file */
	int fd;
	/** non-zero if \a fd was added to the write fd set */
	int check_fd;
};

static int file_write_open(struct writer_node *wn)
{
	struct private_file_write_data *pfwd = para_calloc(
		sizeof(struct private_file_write_data));
	struct file_write_args_info *conf = wn->conf;
	char *filename;
	if (conf->filename_given)
		filename = conf->filename_arg;
	else {
		char *tmp = para_tmpname(), *home = para_homedir();
		filename = make_message("%s/.paraslash/%s", home, tmp);
		free(home);
		free(tmp);
	}
	wn->private_data = pfwd;
	pfwd->fd = open(filename, O_WRONLY | O_CREAT, S_IRUSR | S_IWUSR);
	if (!conf->filename_given)
		free(filename);
	if (pfwd->fd >= 0)
		return 1;
	free(pfwd);
	return -E_FW_OPEN;
}

static int file_write_pre_select(struct sched *s, struct writer_node *wn)
{
	struct private_file_write_data *pfwd = wn->private_data;
	struct writer_node_group *wng = wn->wng;

	pfwd->check_fd = 0;
	if (pfwd->fd <= 0)
		return -E_FW_NO_FILE;
	if (!*wng->loaded)
		return 1;
	para_fd_set(pfwd->fd, &s->wfds, &s->max_fileno);
	pfwd->check_fd = 1;
	return 1;
}

static int file_write_post_select(struct sched *s, struct writer_node *wn)
{
	struct private_file_write_data *pfwd = wn->private_data;
	struct writer_node_group *wng = wn->wng;
	int ret;

	if (!pfwd->check_fd)
		return 1;
	if (*wng->loaded <= wn->written)
		return 1;
	if (!FD_ISSET(pfwd->fd, &s->wfds))
		return 1;
//	PARA_INFO_LOG("writing %zd\n", *wng->loaded);
	ret = write(pfwd->fd, *wng->bufp + wn->written,
		*wng->loaded - wn->written);
	if (ret < 0)
		return -E_FW_WRITE;
	wn->written += ret;
	return 1;
}

static void file_write_close(struct writer_node *wn)
{
	struct private_file_write_data *pfwd = wn->private_data;
	close(pfwd->fd);
	free(pfwd);
}

__malloc static void *file_write_parse_config(const char *options)
{
	struct file_write_args_info *conf
		= para_calloc(sizeof(struct file_write_args_info));
	int ret = file_cmdline_parser_string(options, conf, "file_write");

	PARA_INFO_LOG("conf->filename_given: %d\n", conf->filename_given);
	if (!ret)
		return conf;
	free(conf);
	return NULL;
}

/** the init function of the file writer */
void file_write_init(struct writer *w)
{
	struct file_write_args_info dummy;

	file_cmdline_parser_init(&dummy);
	w->open = file_write_open;
	w->pre_select = file_write_pre_select;
	w->post_select = file_write_post_select;
	w->parse_config = file_write_parse_config;
	w->close = file_write_close;
	w->shutdown = NULL; /* nothing to do */
	w->help = (struct ggo_help) {
		.short_help = file_write_args_info_help,
		.detailed_help = file_write_args_info_detailed_help
	};
	file_cmdline_parser_free(&dummy);
}