/*
 * Copyright (c) 2019 Pablo Neira Ayuso <pablo@netfilter.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 (or any
 * later) as published by the Free Software Foundation.
 */

#include <expression.h>
#include <statement.h>
#include <rule.h>
#include <erec.h>
#include <utils.h>
#include <cache.h>

static unsigned int evaluate_cache_add(struct cmd *cmd, unsigned int flags)
{
	switch (cmd->obj) {
	case CMD_OBJ_CHAIN:
	case CMD_OBJ_SET:
	case CMD_OBJ_COUNTER:
	case CMD_OBJ_QUOTA:
	case CMD_OBJ_LIMIT:
	case CMD_OBJ_SECMARK:
	case CMD_OBJ_FLOWTABLE:
		flags |= NFT_CACHE_TABLE;
		break;
	case CMD_OBJ_SETELEM:
		flags |= NFT_CACHE_TABLE |
			 NFT_CACHE_CHAIN |
			 NFT_CACHE_SET |
			 NFT_CACHE_OBJECT |
			 NFT_CACHE_SETELEM;
		break;
	case CMD_OBJ_RULE:
		flags |= NFT_CACHE_TABLE |
			 NFT_CACHE_CHAIN |
			 NFT_CACHE_SET |
			 NFT_CACHE_OBJECT |
			 NFT_CACHE_FLOWTABLE;

		if (cmd->handle.index.id ||
		    cmd->handle.position.id)
			flags |= NFT_CACHE_RULE | NFT_CACHE_UPDATE;
		break;
	default:
		break;
	}

	return flags;
}

static unsigned int evaluate_cache_del(struct cmd *cmd, unsigned int flags)
{
	switch (cmd->obj) {
	case CMD_OBJ_SETELEM:
		flags |= NFT_CACHE_SETELEM;
		break;
	default:
		break;
	}

	return flags;
}

static unsigned int evaluate_cache_get(struct cmd *cmd, unsigned int flags)
{
	switch (cmd->obj) {
	case CMD_OBJ_SETELEM:
		flags |= NFT_CACHE_TABLE |
			 NFT_CACHE_SET |
			 NFT_CACHE_SETELEM;
		break;
	default:
		break;
	}

	return flags;
}

static unsigned int evaluate_cache_flush(struct cmd *cmd, unsigned int flags)
{
	switch (cmd->obj) {
	case CMD_OBJ_SET:
	case CMD_OBJ_MAP:
	case CMD_OBJ_METER:
		flags |= NFT_CACHE_SET;
		break;
	case CMD_OBJ_RULESET:
		flags |= NFT_CACHE_FLUSHED;
		break;
	default:
		break;
	}

	return flags;
}

static unsigned int evaluate_cache_rename(struct cmd *cmd, unsigned int flags)
{
	switch (cmd->obj) {
	case CMD_OBJ_CHAIN:
		flags |= NFT_CACHE_CHAIN;
		break;
	default:
		break;
	}

	return flags;
}

unsigned int cache_evaluate(struct nft_ctx *nft, struct list_head *cmds)
{
	unsigned int flags = NFT_CACHE_EMPTY;
	struct cmd *cmd;

	list_for_each_entry(cmd, cmds, list) {
		switch (cmd->op) {
		case CMD_ADD:
		case CMD_INSERT:
		case CMD_CREATE:
			flags = evaluate_cache_add(cmd, flags);
			if (nft_output_echo(&nft->output))
				flags |= NFT_CACHE_FULL;
			break;
		case CMD_REPLACE:
			flags = NFT_CACHE_FULL;
			break;
		case CMD_DELETE:
			flags |= NFT_CACHE_TABLE |
				 NFT_CACHE_CHAIN |
				 NFT_CACHE_SET |
				 NFT_CACHE_FLOWTABLE |
				 NFT_CACHE_OBJECT;

			flags = evaluate_cache_del(cmd, flags);
			break;
		case CMD_GET:
			flags = evaluate_cache_get(cmd, flags);
			break;
		case CMD_RESET:
			flags |= NFT_CACHE_TABLE;
			break;
		case CMD_LIST:
		case CMD_EXPORT:
		case CMD_MONITOR:
			flags |= NFT_CACHE_FULL;
			break;
		case CMD_FLUSH:
			flags = evaluate_cache_flush(cmd, flags);
			break;
		case CMD_RENAME:
			flags = evaluate_cache_rename(cmd, flags);
			break;
		case CMD_DESCRIBE:
		case CMD_IMPORT:
			break;
		default:
			break;
		}
	}

	return flags;
}