// Copyright Istio Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package extension

import (
	core "github.com/envoyproxy/go-control-plane/envoy/config/core/v3"
	lua "github.com/envoyproxy/go-control-plane/envoy/extensions/filters/http/lua/v3"

	"istio.io/istio/pilot/pkg/model"
)

// BuildHTTPLuaFilter converts a TrafficExtensionWrapper with Lua config to an Envoy Lua filter configuration.
// Returns nil if the filter is not a Lua filter.
func BuildHTTPLuaFilter(filter *model.TrafficExtensionWrapper) *lua.Lua {
	if filter == nil || filter.GetLua() == nil {
		return nil
	}

	return &lua.Lua{
		DefaultSourceCode: &core.DataSource{
			Specifier: &core.DataSource_InlineString{
				InlineString: filter.GetLua().InlineCode,
			},
		},
	}
}
