package gocommon

import (
	"context"
	"encoding/json"
	"errors"
	"os"
	"time"

	"repositories.action2quare.com/ayo/gocommon/logger"

	"go.mongodb.org/mongo-driver/bson"
	"go.mongodb.org/mongo-driver/bson/primitive"
	"go.mongodb.org/mongo-driver/event"
	"go.mongodb.org/mongo-driver/mongo"
	"go.mongodb.org/mongo-driver/mongo/options"
	"go.mongodb.org/mongo-driver/mongo/readpref"
	"go.mongodb.org/mongo-driver/x/mongo/driver/connstring"
)

type MongoClient struct {
	db  *mongo.Database
	c   *mongo.Client
	ctx context.Context
}

type ConnectionInfo struct {
	Url      string
	Database string
}

type CollectionName string

func ParseObjectID(hexstr string) (out primitive.ObjectID) {
	out, _ = primitive.ObjectIDFromHex(hexstr)
	return
}

func NewMongoConnectionInfo(url string, dbname string) *ConnectionInfo {
	if len(dbname) == 0 {
		panic("dbname is empty")
	}

	if *devflag {
		hostname, _ := os.Hostname()
		dbname = hostname + "-" + dbname
	}

	return &ConnectionInfo{
		Url:      url,
		Database: dbname,
	}
}

func (ci *ConnectionInfo) SetURL(url string) *ConnectionInfo {
	ci.Url = url
	return ci
}

func (ci *ConnectionInfo) SetDatabase(dbname string) *ConnectionInfo {
	ci.Database = dbname
	return ci
}

var errNoDatabaseNameInMongoUri = errors.New("mongo uri has no database name")

func NewMongoClient(ctx context.Context, url string) (MongoClient, error) {
	connstr, err := connstring.ParseAndValidate(url)
	if err != nil {
		return MongoClient{}, err
	}

	if len(connstr.Database) == 0 {
		return MongoClient{}, errNoDatabaseNameInMongoUri
	}

	return newMongoClient(ctx, NewMongoConnectionInfo(url, connstr.Database))
}

func newMongoClient(ctx context.Context, ci *ConnectionInfo) (MongoClient, error) {
	if len(ci.Url) == 0 {
		return MongoClient{}, errors.New("mongo connection string is empty")
	}

	secondaryPref := readpref.SecondaryPreferred()
	//client, err := mongo.NewClient(options.Client().ApplyURI(ci.Url).SetReadPreference(secondaryPref))
	client, err := mongo.NewClient(options.Client().ApplyURI(ci.Url).SetReadPreference(secondaryPref).SetServerMonitor(&event.ServerMonitor{
		ServerOpening: func(evt *event.ServerOpeningEvent) {
			logger.Println("mongodb ServerOpening :", *evt)
		},
		ServerClosed: func(evt *event.ServerClosedEvent) {
			logger.Println("mongodb ServerClosed :", *evt)
		},
		TopologyOpening: func(evt *event.TopologyOpeningEvent) {
			logger.Println("mongodb TopologyOpening :", *evt)
		},
		TopologyClosed: func(evt *event.TopologyClosedEvent) {
			logger.Println("mongodb TopologyClosed :", *evt)
		},
	}))
	if err != nil {
		return MongoClient{}, err
	}

	err = client.Connect(ctx)
	if err != nil {
		return MongoClient{}, err
	}

	// go func() {
	// 	for {
	// 		if err := client.Ping(ctx, nil); err != nil {
	// 			logger.Error("mongo client ping err :", err)
	// 		}

	// 		select {
	// 		case <-time.After(10 * time.Second):
	// 			continue

	// 		case <-ctx.Done():
	// 			return
	// 		}
	// 	}
	// }()

	mdb := client.Database(ci.Database, nil)
	return MongoClient{c: client, db: mdb, ctx: ctx}, nil
}

func (mc *MongoClient) Connected() bool {
	return mc.db != nil && mc.c != nil
}

func (mc *MongoClient) Close() {
	if mc.c != nil {
		mc.c.Disconnect(mc.ctx)
	}
}

func (mc *MongoClient) Drop() error {
	return mc.db.Drop(mc.ctx)
}

func (mc *MongoClient) DropIndex(coll CollectionName, name string) error {
	matchcoll := mc.Collection(coll)
	_, err := matchcoll.Indexes().DropOne(mc.ctx, name)
	if commanderr, ok := err.(mongo.CommandError); ok {
		if commanderr.Code == 27 {
			// 인덱스가 없는 것이므로 그냥 성공
			return nil
		}
	}
	return err
}

func (mc *MongoClient) Watch(coll CollectionName, pipeline mongo.Pipeline, opts ...*options.ChangeStreamOptions) (*mongo.ChangeStream, error) {
	// mc.db.RunCommand()
	if len(opts) == 0 {
		opts = []*options.ChangeStreamOptions{options.ChangeStream().SetFullDocument(options.UpdateLookup).SetMaxAwaitTime(0)}
	}

	stream, err := mc.Collection(coll).Watch(mc.ctx, pipeline, opts...)
	if err != nil {
		if mongoErr, ok := err.(mongo.CommandError); ok {
			logger.Println("MongoClient Watch return err code :", mongoErr, mongoErr.Code)
			if mongoErr.Code == 40573 {
				adminDb := mc.db.Client().Database("admin")
				result := adminDb.RunCommand(mc.ctx, bson.D{
					{Key: "modifyChangeStreams", Value: 1},
					{Key: "database", Value: mc.db.Name()},
					{Key: "collection", Value: coll},
					{Key: "enable", Value: true},
				})

				if result.Err() != nil {
					logger.Println("mc.db.RunCommand failed :", result.Err(), mc.db.Name(), coll)
				} else {
					return mc.Collection(coll).Watch(mc.ctx, pipeline, opts...)
				}
			}
		}

		logger.Fatal(err)
	}

	return stream, err
}

func (mc *MongoClient) Collection(collname CollectionName) *mongo.Collection {
	return mc.db.Collection(string(collname))
}

func (mc *MongoClient) AllAs(coll CollectionName, output any, opts ...*options.FindOptions) error {
	cursor, err := mc.Collection(coll).Find(mc.ctx, bson.D{}, opts...)
	if err != nil {
		return err
	}
	defer cursor.Close(mc.ctx)

	err = cursor.All(mc.ctx, output)
	if err != nil {
		return err
	}

	return nil
}

func (mc *MongoClient) All(coll CollectionName, opts ...*options.FindOptions) ([]bson.M, error) {
	var all []bson.M
	err := mc.AllAs(coll, &all, opts...)
	return all, err
}

func (mc *MongoClient) FindOneAndDelete(coll CollectionName, filter bson.M, opts ...*options.FindOneAndDeleteOptions) (bson.M, error) {
	result := mc.Collection(coll).FindOneAndDelete(mc.ctx, filter, opts...)
	err := result.Err()
	if err != nil {
		if err == mongo.ErrNoDocuments {
			return nil, nil
		}
		return nil, err
	}

	tmp := make(map[string]interface{})
	err = result.Decode(&tmp)
	if err != nil {
		return nil, err
	}

	return bson.M(tmp), nil
}

func (mc *MongoClient) Delete(coll CollectionName, filter bson.M, opts ...*options.DeleteOptions) (bool, error) {
	r, err := mc.Collection(coll).DeleteOne(mc.ctx, filter, opts...)
	if err != nil {
		return false, err
	}

	return r.DeletedCount > 0, nil
}

func (mc *MongoClient) UnsetField(coll CollectionName, filter bson.M, doc bson.M) error {
	_, err := mc.Collection(coll).UpdateOne(mc.ctx, filter, bson.M{
		"$unset": doc,
	})
	return err
}

func (mc *MongoClient) DeleteMany(coll CollectionName, filters bson.D, opts ...*options.DeleteOptions) (int, error) {
	if len(filters) == 0 {
		// 큰일난다
		return 0, nil
	}

	result, err := mc.Collection(coll).DeleteMany(mc.ctx, filters, opts...)
	if err != nil {
		return 0, err
	}

	return int(result.DeletedCount), nil
}

type CommandInsertMany[T any] struct {
	MongoClient
	Collection CollectionName
	Documents  []T
}

func (c *CommandInsertMany[T]) Exec(opts ...*options.InsertManyOptions) (int, error) {
	conv := make([]any, len(c.Documents))
	for i, v := range c.Documents {
		conv[i] = v
	}
	return c.InsertMany(c.Collection, conv, opts...)
}

func (mc *MongoClient) InsertMany(coll CollectionName, documents []interface{}, opts ...*options.InsertManyOptions) (int, error) {
	result, err := mc.Collection(coll).InsertMany(mc.ctx, documents, opts...)
	if err != nil {
		return 0, err
	}

	return len(result.InsertedIDs), nil
}

func (mc *MongoClient) UpdateMany(coll CollectionName, filter bson.M, doc bson.M, opts ...*options.UpdateOptions) (count int, err error) {
	result, e := mc.Collection(coll).UpdateMany(mc.ctx, filter, doc, opts...)

	if e != nil {
		return 0, e
	}

	err = nil
	count = int(result.UpsertedCount + result.ModifiedCount)
	return
}

type Marshaler interface {
	MarshalBSON() ([]byte, error)
}

type JsonDefaultMashaller struct {
	doc *bson.M
}

func (m *JsonDefaultMashaller) MarshalBSON() ([]byte, error) {
	return json.Marshal(m.doc)
}

func (mc *MongoClient) Update(coll CollectionName, filter bson.M, doc interface{}, opts ...*options.UpdateOptions) (worked bool, newid interface{}, err error) {
	result, e := mc.Collection(coll).UpdateOne(mc.ctx, filter, doc, opts...)

	if e != nil {
		return false, "", e
	}

	err = nil
	worked = result.MatchedCount > 0 || result.UpsertedCount > 0 || result.ModifiedCount > 0
	newid = result.UpsertedID
	return
}

func (mc *MongoClient) UpsertOne(coll CollectionName, filter bson.M, doc interface{}) (worked bool, newid interface{}, err error) {
	return mc.Update(coll, filter, bson.M{
		"$set": doc,
	}, options.Update().SetUpsert(true))

	// return mc.Update(coll, filter, &JsonDefaultMashaller{doc: &bson.M{
	// 	"$set": doc,
	// }}, options.Update().SetUpsert(true))
}

func (mc *MongoClient) FindOneAs(coll CollectionName, filter bson.M, out interface{}, opts ...*options.FindOneOptions) error {
	err := mc.Collection(coll).FindOne(mc.ctx, filter, opts...).Decode(out)
	if err == mongo.ErrNoDocuments {
		err = nil
	}
	return err
}

func (mc *MongoClient) FindOne(coll CollectionName, filter bson.M, opts ...*options.FindOneOptions) (doc bson.M, err error) {
	result := mc.Collection(coll).FindOne(mc.ctx, filter, opts...)
	tmp := make(map[string]interface{})
	err = result.Decode(&tmp)
	if err == nil {
		doc = bson.M(tmp)
	} else if err == mongo.ErrNoDocuments {
		err = nil
	}

	return
}

func (mc *MongoClient) FindOneAndUpdateAs(coll CollectionName, filter bson.M, doc bson.M, out interface{}, opts ...*options.FindOneAndUpdateOptions) error {
	result := mc.Collection(coll).FindOneAndUpdate(mc.ctx, filter, doc, opts...)
	err := result.Decode(out)
	if err == nil {
		return nil
	}

	if err == mongo.ErrNoDocuments {
		return nil
	}

	return err
}

func (mc *MongoClient) FindOneAndUpdate(coll CollectionName, filter bson.M, doc bson.M, opts ...*options.FindOneAndUpdateOptions) (olddoc bson.M, err error) {
	result := mc.Collection(coll).FindOneAndUpdate(mc.ctx, filter, doc, opts...)
	tmp := make(map[string]interface{})
	err = result.Decode(&tmp)
	if err == nil {
		olddoc = bson.M(tmp)
	} else if err == mongo.ErrNoDocuments {
		err = nil
	}

	return
}

func (mc *MongoClient) Exists(coll CollectionName, filter bson.M) (bool, error) {
	cnt, err := mc.Collection(coll).CountDocuments(mc.ctx, filter, options.Count().SetLimit(1))
	if err != nil {
		return false, err
	}
	return cnt > 0, nil
}

func (mc *MongoClient) SearchText(coll CollectionName, text string, opts ...*options.FindOptions) ([]bson.M, error) {
	cursor, err := mc.Collection(coll).Find(mc.ctx, bson.M{"$text": bson.M{"$search": text}}, opts...)
	if err != nil {
		return nil, err
	}
	defer cursor.Close(mc.ctx)

	var output []bson.M
	err = cursor.All(mc.ctx, &output)
	if err != nil {
		return nil, err
	}

	return output, nil
}

func (mc *MongoClient) FindAll(coll CollectionName, filter bson.M, opts ...*options.FindOptions) ([]bson.M, error) {
	cursor, err := mc.Collection(coll).Find(mc.ctx, filter, opts...)
	if err != nil {
		return nil, err
	}
	defer cursor.Close(mc.ctx)

	var output []bson.M
	err = cursor.All(mc.ctx, &output)
	if err != nil {
		return nil, err
	}

	return output, nil
}

func (mc *MongoClient) FindAllAs(coll CollectionName, filter bson.M, output interface{}, opts ...*options.FindOptions) error {
	cursor, err := mc.Collection(coll).Find(mc.ctx, filter, opts...)
	if err != nil {
		return err
	}
	defer cursor.Close(mc.ctx)

	err = cursor.All(mc.ctx, output)
	if err != nil {
		return err
	}
	return nil
}

func (mc *MongoClient) MakeExpireIndex(coll CollectionName, expireSeconds int32) error {
	matchcoll := mc.Collection(coll)
	indices, err := matchcoll.Indexes().List(mc.ctx, options.ListIndexes().SetMaxTime(time.Second))
	if err != nil {
		return err
	}

	allindices := make([]interface{}, 0)
	err = indices.All(mc.ctx, &allindices)
	if err != nil {
		return err
	}

	tsfound := false
	var tsname string
	var exp int32

IndexSearchLabel:
	for _, index := range allindices {
		d := index.(bson.D)
		key := d.Map()["key"].(bson.D)
		for _, kd := range key {
			if kd.Key == "_ts" {
				tsfound = true

				if v, ok := d.Map()["name"]; ok {
					tsname = v.(string)
				}
				if v, ok := d.Map()["expireAfterSeconds"]; ok {
					exp = v.(int32)
				}
				break IndexSearchLabel
			}
		}
	}

	if tsfound {
		if exp == expireSeconds {
			return nil
		}
		_, err = matchcoll.Indexes().DropOne(mc.ctx, tsname)
		if err != nil {
			return err
		}
	}

	mod := mongo.IndexModel{
		Keys:    primitive.M{"_ts": 1},
		Options: options.Index().SetExpireAfterSeconds(expireSeconds),
	}

	_, err = matchcoll.Indexes().CreateOne(mc.ctx, mod)
	return err
}

func (mc *MongoClient) makeIndicesWithOption(coll CollectionName, indices map[string]bson.D, opts ...*options.IndexOptions) error {
	collection := mc.Collection(coll)
	cursor, err := collection.Indexes().List(mc.ctx, options.ListIndexes().SetMaxTime(time.Second))
	if err != nil {
		return err
	}
	defer cursor.Close(mc.ctx)

	found := make(map[string]bool)
	for k := range indices {
		found[k] = false
	}

	for cursor.TryNext(mc.ctx) {
		rawval := cursor.Current
		name := rawval.Lookup("name").StringValue()
		if _, ok := indices[name]; ok {
			found[name] = true
		}
	}

	for name, exist := range found {
		if !exist {
			v := indices[name]
			var mod mongo.IndexModel
			if len(v) == 1 {
				mod = mongo.IndexModel{
					Keys:    primitive.M{v[0].Key: v[0].Value},
					Options: options.MergeIndexOptions(append(opts, options.Index().SetName(name))...),
				}
			} else {
				mod = mongo.IndexModel{
					Keys:    indices[name],
					Options: options.MergeIndexOptions(append(opts, options.Index().SetName(name))...),
				}
			}

			_, err = collection.Indexes().CreateOne(mc.ctx, mod)
			if err != nil {
				return err
			}
		}
	}
	return nil
}

func (mc *MongoClient) MakeUniqueIndices(coll CollectionName, indices map[string]bson.D, opts ...*options.IndexOptions) error {
	return mc.makeIndicesWithOption(coll, indices, append(opts, options.Index().SetUnique(true))...)
}

func (mc *MongoClient) MakeIndices(coll CollectionName, indices map[string]bson.D, opts ...*options.IndexOptions) error {
	return mc.makeIndicesWithOption(coll, indices, opts...)
}