package controller

import (
	"context"
	"crypto/md5"
	"errors"
	"fmt"
	"github.com/OpenIMSDK/protocol/constant"
	"github.com/OpenIMSDK/tools/tx"
	"github.com/openimsdk/open-im-server/v3/pkg/common/db/table/relation"
	"sort"
	"strings"
)

type AesKeyDatabase interface {
	AcquireAesKey(ctx context.Context, conversationType int32, userId, friendId, groupId string) (key *relation.AesKeyModel, err error)
	AcquireAesKeys(ctx context.Context, userId string) (key []*relation.AesKeyModel, err error)
}

type aesKeyDatabase struct {
	key relation.AesKeyModelInterface
	tx  tx.Tx
}

func NewAesKeyDatabase(key relation.AesKeyModelInterface, tx tx.Tx) *aesKeyDatabase {
	return &aesKeyDatabase{key: key, tx: tx}
}

func (a *aesKeyDatabase) AcquireAesKey(ctx context.Context, conversationType int32, userId, friendId, groupId string) (key *relation.AesKeyModel, err error) {
	var keyConversationsID string
	switch conversationType {
	case constant.SingleChatType:
		if userId == "" || friendId == "" {
			return nil, errors.New("userId or friendId is null")
		}
		keyConversationsID = a.generateKeyConversationsID(userId, friendId)
	case constant.GroupChatType:
		if userId == "" || groupId == "" {
			return nil, errors.New("userId or groupId is null")
		}
		keyConversationsID = a.generateKeyConversationsID(groupId)
	default:
		return nil, errors.New("conversationType err")
	}
	aesKey, err := a.key.GetAesKey(ctx, keyConversationsID)
	if err != nil {
		generateAesKey := a.generateAesKey(keyConversationsID)
		keyModel := relation.AesKeyModel{
			KeyConversationsID: keyConversationsID,
			Key:                generateAesKey,
			ConversationType:   conversationType,
			OwnerUserID:        userId,
			FriendUserID:       friendId,
			GroupID:            groupId,
		}
		var keys []*relation.AesKeyModel
		keys = append(keys, &keyModel)
		err := a.key.Installs(ctx, keys)
		if err != nil {
			return &keyModel, err
		}
	}
	return aesKey, nil
}

func (a *aesKeyDatabase) AcquireAesKeys(ctx context.Context, userId string) (key []*relation.AesKeyModel, err error) {
	return a.key.GetAllAesKey(ctx, userId)
}

func (a *aesKeyDatabase) generateKeyConversationsID(args ...string) string {
	sort.Strings(args)
	combinedStr := strings.Join(args, "")
	return combinedStr
}
func (a *aesKeyDatabase) generateAesKey(keyConversationsID string) string {
	md5Value := md5.Sum([]byte(keyConversationsID))
	md5Str := fmt.Sprintf("%x", md5Value)
	return md5Str[:16]
}