// Copyright 2018-2021 CERN
//
// 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.
//
// In applying this license, CERN does not waive the privileges and immunities
// granted to it by virtue of its status as an Intergovernmental Organization
// or submit itself to any jurisdiction.

// Package appctx creates a context with useful
// components attached to the context like loggers and
// token managers.
package appctx

import (
	"net/http"

	"github.com/cs3org/reva/v2/pkg/appctx"
	"github.com/rs/zerolog"
	"go.opentelemetry.io/otel/trace"
)

// name is the Tracer name used to identify this instrumentation library.
const tracerName = "appctx"

// New returns a new HTTP middleware that stores the log
// in the context with request ID information.
func New(log zerolog.Logger, tp trace.TracerProvider) func(http.Handler) http.Handler {
	chain := func(h http.Handler) http.Handler {
		return handler(log, tp, h)
	}
	return chain
}

func handler(log zerolog.Logger, tp trace.TracerProvider, h http.Handler) http.Handler {

	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		ctx := r.Context()
		span := trace.SpanFromContext(ctx)
		defer span.End()
		if !span.SpanContext().HasTraceID() {
			ctx, span = tp.Tracer(tracerName).Start(ctx, "http interceptor")
		}

		sub := log.With().Str("traceid", span.SpanContext().TraceID().String()).Logger()
		ctx = appctx.WithLogger(ctx, &sub)
		ctx = appctx.WithTracerProvider(ctx, tp)
		r = r.WithContext(ctx)
		h.ServeHTTP(w, r)
	})
}
