// Licensed to the LF AI & Data foundation under one
// or more contributor license agreements. See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership. The ASF licenses this file
// to you 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 accesslog

import (
	"context"
	"fmt"
	"strings"
	"time"

	"github.com/cockroachdb/errors"
	"google.golang.org/grpc"
	"google.golang.org/grpc/metadata"

	"github.com/milvus-io/milvus/pkg/util"
	"github.com/milvus-io/milvus/pkg/util/crypto"
)

type AccessKey struct{}

func UnaryAccessLogInterceptor(ctx context.Context, req any, info *grpc.UnaryServerInfo, handler grpc.UnaryHandler) (interface{}, error) {
	accessInfo := NewGrpcAccessInfo(ctx, info, req)
	newCtx := context.WithValue(ctx, AccessKey{}, accessInfo)
	resp, err := handler(newCtx, req)
	accessInfo.SetResult(resp, err)
	accessInfo.Write()
	return resp, err
}

func UnaryUpdateAccessInfoInterceptor(ctx context.Context, req any, info *grpc.UnaryServerInfo, handler grpc.UnaryHandler) (interface{}, error) {
	accessInfo := ctx.Value(AccessKey{}).(*GrpcAccessInfo)
	accessInfo.UpdateCtx(ctx)
	return handler(ctx, req)
}

func join(path1, path2 string) string {
	if strings.HasSuffix(path1, "/") {
		return path1 + path2
	}
	return path1 + "/" + path2
}

func timeFromName(filename, prefix, ext string) (time.Time, error) {
	if !strings.HasPrefix(filename, prefix) {
		return time.Time{}, errors.New("mismatched prefix")
	}
	if !strings.HasSuffix(filename, ext) {
		return time.Time{}, errors.New("mismatched extension")
	}
	ts := filename[len(prefix) : len(filename)-len(ext)]
	return time.Parse(timeNameFormat, ts)
}

func getCurUserFromContext(ctx context.Context) (string, error) {
	md, ok := metadata.FromIncomingContext(ctx)
	if !ok {
		return "", fmt.Errorf("fail to get md from the context")
	}
	authorization, ok := md[strings.ToLower(util.HeaderAuthorize)]
	if !ok || len(authorization) < 1 {
		return "", fmt.Errorf("fail to get authorization from the md, authorize:[%s]", util.HeaderAuthorize)
	}
	token := authorization[0]
	rawToken, err := crypto.Base64Decode(token)
	if err != nil {
		return "", fmt.Errorf("fail to decode the token, token: %s", token)
	}
	secrets := strings.SplitN(rawToken, util.CredentialSeperator, 2)
	if len(secrets) < 2 {
		return "", fmt.Errorf("fail to get user info from the raw token, raw token: %s", rawToken)
	}
	username := secrets[0]
	return username, nil
}