/* opkg_upgrade.c - the opkg package management system

   Carl D. Worth
   Copyright (C) 2001 University of Southern California

   Copyright (C) 2003 Daniele Nicolodi <daniele@grinta.net>

   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, 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.
*/

#include <stdio.h>
#include <stdlib.h>

#include "opkg_install.h"
#include "opkg_upgrade.h"
#include "opkg_message.h"

int opkg_upgrade_pkg(pkg_t * old)
{
	pkg_t *new;
	int cmp;
	char *old_version, *new_version;

	if (old->state_flag & SF_HOLD) {
		opkg_msg(NOTICE, "Not upgrading package %s which is marked "
			 "hold (flags=%#x).\n", old->name, old->state_flag);
		return 0;
	}

	new = pkg_hash_fetch_best_installation_candidate_by_name(old->name);
	if (new == NULL) {
		old_version = pkg_version_str_alloc(old);
		opkg_msg(NOTICE, "Assuming locally installed package %s (%s) "
			 "is up to date.\n", old->name, old_version);
		free(old_version);
		return 0;
	}

	old_version = pkg_version_str_alloc(old);
	new_version = pkg_version_str_alloc(new);

	cmp = pkg_compare_versions(old, new);
	opkg_msg(DEBUG, "Comparing visible versions of pkg %s:"
		 "\n\t%s is installed "
		 "\n\t%s is available "
		 "\n\t%d was comparison result\n",
		 old->name, old_version, new_version, cmp);
	if (cmp == 0) {
		opkg_msg(INFO,
			 "Package %s (%s) installed in %s is up to date.\n",
			 old->name, old_version, old->dest->name);
		free(old_version);
		free(new_version);
		return 0;
	} else if (cmp > 0) {
		opkg_msg(NOTICE,
			 "Not downgrading package %s on %s from %s to %s.\n",
			 old->name, old->dest->name, old_version, new_version);
		free(old_version);
		free(new_version);
		return 0;
	} else if (cmp < 0) {
		new->dest = old->dest;
		old->state_want = SW_DEINSTALL;
	}

	free(old_version);
	free(new_version);
	new->state_flag |= SF_USER;
	return opkg_install_pkg(new, 1);
}

static void
pkg_hash_check_installed_pkg_helper(const char *pkg_name, void *entry,
				    void *data)
{
	struct active_list *item, *head = (struct active_list *)data;
	abstract_pkg_t *ab_pkg = (abstract_pkg_t *) entry;
	pkg_vec_t *pkg_vec = ab_pkg->pkgs;
	int j;

	if (!pkg_vec)
		return;

	for (j = 0; j < pkg_vec->len; j++) {
		pkg_t *pkg = pkg_vec->pkgs[j];
		if (pkg->state_status == SS_INSTALLED
		    || pkg->state_status == SS_UNPACKED) {
			item = active_list_head_new();
			item->pkg = pkg;
			active_list_add(head, item);
		}
	}
}

struct active_list *prepare_upgrade_list(void)
{
	struct active_list *head = active_list_head_new();
	struct active_list *all = active_list_head_new();
	struct active_list *node = NULL;

	/* ensure all data is valid */
	pkg_info_preinstall_check();

	hash_table_foreach(&conf->pkg_hash, pkg_hash_check_installed_pkg_helper,
			   all);
	for (node = active_list_next(all, all); node;
	     node = active_list_next(all, node)) {
		pkg_t *old, *new;
		int cmp;

		old = node->pkg;
		new =
		    pkg_hash_fetch_best_installation_candidate_by_name(old->
								       name);

		if (new == NULL)
			continue;

		cmp = pkg_compare_versions(old, new);

		if (cmp < 0) {
			node = active_list_move_node(all, head, node);
		}
	}
	active_list_head_delete(all);
	return head;
}