// Copyright © 2023 OpenIM. All rights reserved.
//
// 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 unrelation

import (
	"context"
	"errors"
	"fmt"

	"go.mongodb.org/mongo-driver/bson"
	"go.mongodb.org/mongo-driver/bson/primitive"
	"go.mongodb.org/mongo-driver/mongo"
	"go.mongodb.org/mongo-driver/mongo/options"

	unRelationTb "github.com/OpenIMSDK/Open-IM-Server/pkg/common/db/table/unrelation"
	"github.com/OpenIMSDK/Open-IM-Server/pkg/utils"
)

type ExtendMsgSetMongoDriver struct {
	mgoDB                  *mongo.Database
	ExtendMsgSetCollection *mongo.Collection
}

func NewExtendMsgSetMongoDriver(mgoDB *mongo.Database) unRelationTb.ExtendMsgSetModelInterface {
	return &ExtendMsgSetMongoDriver{mgoDB: mgoDB, ExtendMsgSetCollection: mgoDB.Collection(unRelationTb.CExtendMsgSet)}
}

func (e *ExtendMsgSetMongoDriver) CreateExtendMsgSet(ctx context.Context, set *unRelationTb.ExtendMsgSetModel) error {
	_, err := e.ExtendMsgSetCollection.InsertOne(ctx, set)
	return err
}

func (e *ExtendMsgSetMongoDriver) GetAllExtendMsgSet(
	ctx context.Context,
	ID string,
	opts *unRelationTb.GetAllExtendMsgSetOpts,
) (sets []*unRelationTb.ExtendMsgSetModel, err error) {
	regex := fmt.Sprintf("^%s", ID)
	var findOpts *options.FindOptions
	if opts != nil {
		if opts.ExcludeExtendMsgs {
			findOpts = &options.FindOptions{}
			findOpts.SetProjection(bson.M{"extend_msgs": 0})
		}
	}
	cursor, err := e.ExtendMsgSetCollection.Find(ctx, bson.M{"doc_id": primitive.Regex{Pattern: regex}}, findOpts)
	if err != nil {
		return nil, utils.Wrap(err, "")
	}
	err = cursor.All(ctx, &sets)
	if err != nil {
		return nil, utils.Wrap(err, fmt.Sprintf("cursor is %s", cursor.Current.String()))
	}
	return sets, nil
}

func (e *ExtendMsgSetMongoDriver) GetExtendMsgSet(
	ctx context.Context,
	conversationID string,
	sessionType int32,
	maxMsgUpdateTime int64,
) (*unRelationTb.ExtendMsgSetModel, error) {
	var err error
	findOpts := options.Find().
		SetLimit(1).
		SetSkip(0).
		SetSort(bson.M{"source_id": -1}).
		SetProjection(bson.M{"extend_msgs": 0})
	// update newest
	find := bson.M{
		"source_id":    primitive.Regex{Pattern: fmt.Sprintf("^%s", conversationID)},
		"session_type": sessionType,
	}
	if maxMsgUpdateTime > 0 {
		find["max_msg_update_time"] = maxMsgUpdateTime
	}
	result, err := e.ExtendMsgSetCollection.Find(ctx, find, findOpts)
	if err != nil {
		return nil, utils.Wrap(err, "")
	}
	var setList []unRelationTb.ExtendMsgSetModel
	if err := result.All(ctx, &setList); err != nil {
		return nil, utils.Wrap(err, "")
	}
	if len(setList) == 0 {
		return nil, nil
	}
	return &setList[0], nil
}

// first modify msg
func (e *ExtendMsgSetMongoDriver) InsertExtendMsg(
	ctx context.Context,
	conversationID string,
	sessionType int32,
	msg *unRelationTb.ExtendMsgModel,
) error {
	set, err := e.GetExtendMsgSet(ctx, conversationID, sessionType, 0)
	if err != nil {
		return utils.Wrap(err, "")
	}
	if set == nil || set.ExtendMsgNum >= set.GetExtendMsgMaxNum() {
		var index int32
		if set != nil {
			index = set.SplitConversationIDAndGetIndex()
		}
		err = e.CreateExtendMsgSet(ctx, &unRelationTb.ExtendMsgSetModel{
			ConversationID:   set.GetConversationID(conversationID, index),
			SessionType:      sessionType,
			ExtendMsgs:       map[string]unRelationTb.ExtendMsgModel{msg.ClientMsgID: *msg},
			ExtendMsgNum:     1,
			CreateTime:       msg.MsgFirstModifyTime,
			MaxMsgUpdateTime: msg.MsgFirstModifyTime,
		})
	} else {
		_, err = e.ExtendMsgSetCollection.UpdateOne(ctx, bson.M{"conversation_id": set.ConversationID, "session_type": sessionType}, bson.M{"$set": bson.M{"max_msg_update_time": msg.MsgFirstModifyTime, "$inc": bson.M{"extend_msg_num": 1}, fmt.Sprintf("extend_msgs.%s", msg.ClientMsgID): msg}})
	}
	return utils.Wrap(err, "")
}

// insert or update
func (e *ExtendMsgSetMongoDriver) InsertOrUpdateReactionExtendMsgSet(
	ctx context.Context,
	conversationID string,
	sessionType int32,
	clientMsgID string,
	msgFirstModifyTime int64,
	reactionExtensionList map[string]*unRelationTb.KeyValueModel,
) error {
	var updateBson = bson.M{}
	for _, v := range reactionExtensionList {
		updateBson[fmt.Sprintf("extend_msgs.%s.%s", clientMsgID, v.TypeKey)] = v
	}
	upsert := true
	opt := &options.UpdateOptions{
		Upsert: &upsert,
	}
	set, err := e.GetExtendMsgSet(ctx, conversationID, sessionType, msgFirstModifyTime)
	if err != nil {
		return utils.Wrap(err, "")
	}
	if set == nil {
		return fmt.Errorf("conversationID %s has no set", conversationID)
	}
	_, err = e.ExtendMsgSetCollection.UpdateOne(
		ctx,
		bson.M{"source_id": set.ConversationID, "session_type": sessionType},
		bson.M{"$set": updateBson},
		opt,
	)
	return utils.Wrap(err, "")
}

// delete TypeKey
func (e *ExtendMsgSetMongoDriver) DeleteReactionExtendMsgSet(
	ctx context.Context,
	conversationID string,
	sessionType int32,
	clientMsgID string,
	msgFirstModifyTime int64,
	reactionExtensionList map[string]*unRelationTb.KeyValueModel,
) error {
	var updateBson = bson.M{}
	for _, v := range reactionExtensionList {
		updateBson[fmt.Sprintf("extend_msgs.%s.%s", clientMsgID, v.TypeKey)] = ""
	}
	set, err := e.GetExtendMsgSet(ctx, conversationID, sessionType, msgFirstModifyTime)
	if err != nil {
		return utils.Wrap(err, "")
	}
	if set == nil {
		return fmt.Errorf("conversationID %s has no set", conversationID)
	}
	_, err = e.ExtendMsgSetCollection.UpdateOne(
		ctx,
		bson.M{"source_id": set.ConversationID, "session_type": sessionType},
		bson.M{"$unset": updateBson},
	)
	return err
}

func (e *ExtendMsgSetMongoDriver) TakeExtendMsg(
	ctx context.Context,
	conversationID string,
	sessionType int32,
	clientMsgID string,
	maxMsgUpdateTime int64,
) (extendMsg *unRelationTb.ExtendMsgModel, err error) {
	findOpts := options.Find().
		SetLimit(1).
		SetSkip(0).
		SetSort(bson.M{"source_id": -1}).
		SetProjection(bson.M{fmt.Sprintf("extend_msgs.%s", clientMsgID): 1})
	regex := fmt.Sprintf("^%s", conversationID)
	result, err := e.ExtendMsgSetCollection.Find(
		ctx,
		bson.M{
			"source_id":           primitive.Regex{Pattern: regex},
			"session_type":        sessionType,
			"max_msg_update_time": bson.M{"$lte": maxMsgUpdateTime},
		},
		findOpts,
	)
	if err != nil {
		return nil, utils.Wrap(err, "")
	}
	var setList []unRelationTb.ExtendMsgSetModel
	if err := result.All(ctx, &setList); err != nil {
		return nil, utils.Wrap(err, "")
	}
	if len(setList) == 0 {
		return nil, utils.Wrap(errors.New("GetExtendMsg failed, len(setList) == 0"), "")
	}
	if v, ok := setList[0].ExtendMsgs[clientMsgID]; ok {
		return &v, nil
	}
	return nil, fmt.Errorf("cant find client msg id: %s", clientMsgID)
}