/*
 * Copyright (c) 2021, Sam Atkins <atkinssj@serenityos.org>
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#include <LibWeb/CSS/CSSRuleList.h>
#include <LibWeb/DOM/ExceptionOr.h>

namespace Web::CSS {

CSSRuleList::CSSRuleList(NonnullRefPtrVector<CSSRule>&& rules)
    : m_rules(move(rules))
{
}

CSSRuleList::~CSSRuleList()
{
}

bool CSSRuleList::is_supported_property_index(u32 index) const
{
    // The object’s supported property indices are the numbers in the range zero to one less than the number of CSSRule objects represented by the collection.
    // If there are no such CSSRule objects, then there are no supported property indices.
    return index < m_rules.size();
}

// https://drafts.csswg.org/cssom/#insert-a-css-rule
DOM::ExceptionOr<unsigned> CSSRuleList::insert_a_css_rule(NonnullRefPtr<CSSRule> rule, u32 index)
{
    // 1. Set length to the number of items in list.
    auto length = m_rules.size();

    // 2. If index is greater than length, then throw an IndexSizeError exception.
    if (index > length)
        return DOM::IndexSizeError::create("CSS rule index out of bounds.");

    // NOTE: These steps don't apply since we're receiving a parsed rule.
    // 3. Set new rule to the results of performing parse a CSS rule on argument rule.
    // 4. If new rule is a syntax error, throw a SyntaxError exception.

    // FIXME: 5. If new rule cannot be inserted into list at the zero-index position index due to constraints specified by CSS, then throw a HierarchyRequestError exception. [CSS21]

    // FIXME: 6. If new rule is an @namespace at-rule, and list contains anything other than @import at-rules, and @namespace at-rules, throw an InvalidStateError exception.

    // 7. Insert new rule into list at the zero-indexed position index.
    m_rules.insert(index, move(rule));

    // 8. Return index.
    return index;
}

// https://drafts.csswg.org/cssom/#remove-a-css-rule
DOM::ExceptionOr<void> CSSRuleList::remove_a_css_rule(u32 index)
{
    // 1. Set length to the number of items in list.
    auto length = m_rules.size();

    // 2. If index is greater than or equal to length, then throw an IndexSizeError exception.
    if (index >= length)
        return DOM::IndexSizeError::create("CSS rule index out of bounds.");

    // 3. Set old rule to the indexth item in list.
    auto& old_rule = m_rules[index];

    // FIXME: 4. If old rule is an @namespace at-rule, and list contains anything other than @import at-rules, and @namespace at-rules, throw an InvalidStateError exception.
    (void)old_rule;

    // 5. Remove rule old rule from list at the zero-indexed position index.
    m_rules.remove(index);

    // FIXME: 6. Set old rule’s parent CSS rule and parent CSS style sheet to null.

    return {};
}

}