package monc

import (
	"context"
	"log"

	"github.com/zeromicro/go-zero/core/stores/cache"
	"github.com/zeromicro/go-zero/core/stores/mon"
	"github.com/zeromicro/go-zero/core/stores/redis"
	"github.com/zeromicro/go-zero/core/syncx"
	"go.mongodb.org/mongo-driver/mongo"
	mopt "go.mongodb.org/mongo-driver/mongo/options"
)

var (
	// ErrNotFound is an alias of mongo.ErrNoDocuments.
	ErrNotFound = mongo.ErrNoDocuments

	// can't use one SingleFlight per conn, because multiple conns may share the same cache key.
	singleFlight = syncx.NewSingleFlight()
	stats        = cache.NewStat("monc")
)

// A Model is a mongo model that built with cache capability.
type Model struct {
	*mon.Model
	cache cache.Cache
}

// MustNewModel returns a Model with a cache cluster, exists on errors.
func MustNewModel(uri, db, collection string, c cache.CacheConf, opts ...cache.Option) *Model {
	model, err := NewModel(uri, db, collection, c, opts...)
	if err != nil {
		log.Fatal(err)
	}

	return model
}

// MustNewNodeModel returns a Model with a cache node, exists on errors.
func MustNewNodeModel(uri, db, collection string, rds *redis.Redis, opts ...cache.Option) *Model {
	model, err := NewNodeModel(uri, db, collection, rds, opts...)
	if err != nil {
		log.Fatal(err)
	}

	return model
}

// NewModel returns a Model with a cache cluster.
func NewModel(uri, db, collection string, conf cache.CacheConf, opts ...cache.Option) (*Model, error) {
	c := cache.New(conf, singleFlight, stats, mongo.ErrNoDocuments, opts...)
	return NewModelWithCache(uri, db, collection, c)
}

// NewModelWithCache returns a Model with a custom cache.
func NewModelWithCache(uri, db, collection string, c cache.Cache) (*Model, error) {
	return newModel(uri, db, collection, c)
}

// NewNodeModel returns a Model with a cache node.
func NewNodeModel(uri, db, collection string, rds *redis.Redis, opts ...cache.Option) (*Model, error) {
	c := cache.NewNode(rds, singleFlight, stats, mongo.ErrNoDocuments, opts...)
	return NewModelWithCache(uri, db, collection, c)
}

// newModel returns a Model with the given cache.
func newModel(uri, db, collection string, c cache.Cache) (*Model, error) {
	model, err := mon.NewModel(uri, db, collection)
	if err != nil {
		return nil, err
	}

	return &Model{
		Model: model,
		cache: c,
	}, nil
}

// DelCache deletes the cache with given keys.
func (mm *Model) DelCache(ctx context.Context, keys ...string) error {
	return mm.cache.DelCtx(ctx, keys...)
}

// DeleteOne deletes the document with given filter, and remove it from cache.
func (mm *Model) DeleteOne(ctx context.Context, key string, filter interface{},
	opts ...*mopt.DeleteOptions) (int64, error) {
	val, err := mm.Model.DeleteOne(ctx, filter, opts...)
	if err != nil {
		return 0, err
	}

	if err := mm.DelCache(ctx, key); err != nil {
		return 0, err
	}

	return val, nil
}

// DeleteOneNoCache deletes the document with given filter.
func (mm *Model) DeleteOneNoCache(ctx context.Context, filter interface{},
	opts ...*mopt.DeleteOptions) (int64, error) {
	return mm.Model.DeleteOne(ctx, filter, opts...)
}

// FindOne unmarshals a record into v with given key and query.
func (mm *Model) FindOne(ctx context.Context, key string, v, filter interface{},
	opts ...*mopt.FindOneOptions) error {
	return mm.cache.TakeCtx(ctx, v, key, func(v interface{}) error {
		return mm.Model.FindOne(ctx, v, filter, opts...)
	})
}

// FindOneNoCache unmarshals a record into v with query, without cache.
func (mm *Model) FindOneNoCache(ctx context.Context, v, filter interface{},
	opts ...*mopt.FindOneOptions) error {
	return mm.Model.FindOne(ctx, v, filter, opts...)
}

// FindOneAndDelete deletes the document with given filter, and unmarshals it into v.
func (mm *Model) FindOneAndDelete(ctx context.Context, key string, v, filter interface{},
	opts ...*mopt.FindOneAndDeleteOptions) error {
	if err := mm.Model.FindOneAndDelete(ctx, v, filter, opts...); err != nil {
		return err
	}

	return mm.DelCache(ctx, key)
}

// FindOneAndDeleteNoCache deletes the document with given filter, and unmarshals it into v.
func (mm *Model) FindOneAndDeleteNoCache(ctx context.Context, v, filter interface{},
	opts ...*mopt.FindOneAndDeleteOptions) error {
	return mm.Model.FindOneAndDelete(ctx, v, filter, opts...)
}

// FindOneAndReplace replaces the document with given filter with replacement, and unmarshals it into v.
func (mm *Model) FindOneAndReplace(ctx context.Context, key string, v, filter interface{},
	replacement interface{}, opts ...*mopt.FindOneAndReplaceOptions) error {
	if err := mm.Model.FindOneAndReplace(ctx, v, filter, replacement, opts...); err != nil {
		return err
	}

	return mm.DelCache(ctx, key)
}

// FindOneAndReplaceNoCache replaces the document with given filter with replacement, and unmarshals it into v.
func (mm *Model) FindOneAndReplaceNoCache(ctx context.Context, v, filter interface{},
	replacement interface{}, opts ...*mopt.FindOneAndReplaceOptions) error {
	return mm.Model.FindOneAndReplace(ctx, v, filter, replacement, opts...)
}

// FindOneAndUpdate updates the document with given filter with update, and unmarshals it into v.
func (mm *Model) FindOneAndUpdate(ctx context.Context, key string, v, filter interface{},
	update interface{}, opts ...*mopt.FindOneAndUpdateOptions) error {
	if err := mm.Model.FindOneAndUpdate(ctx, v, filter, update, opts...); err != nil {
		return err
	}

	return mm.DelCache(ctx, key)
}

// FindOneAndUpdateNoCache updates the document with given filter with update, and unmarshals it into v.
func (mm *Model) FindOneAndUpdateNoCache(ctx context.Context, v, filter interface{},
	update interface{}, opts ...*mopt.FindOneAndUpdateOptions) error {
	return mm.Model.FindOneAndUpdate(ctx, v, filter, update, opts...)
}

// GetCache unmarshal the cache into v with given key.
func (mm *Model) GetCache(key string, v interface{}) error {
	return mm.cache.Get(key, v)
}

// InsertOne inserts a single document into the collection, and remove the cache placeholder.
func (mm *Model) InsertOne(ctx context.Context, key string, document interface{},
	opts ...*mopt.InsertOneOptions) (*mongo.InsertOneResult, error) {
	res, err := mm.Model.InsertOne(ctx, document, opts...)
	if err != nil {
		return nil, err
	}

	if err = mm.DelCache(ctx, key); err != nil {
		return nil, err
	}

	return res, nil
}

// InsertOneNoCache inserts a single document into the collection.
func (mm *Model) InsertOneNoCache(ctx context.Context, document interface{},
	opts ...*mopt.InsertOneOptions) (*mongo.InsertOneResult, error) {
	return mm.Model.InsertOne(ctx, document, opts...)
}

// ReplaceOne replaces a single document in the collection, and remove the cache.
func (mm *Model) ReplaceOne(ctx context.Context, key string, filter, replacement interface{},
	opts ...*mopt.ReplaceOptions) (*mongo.UpdateResult, error) {
	res, err := mm.Model.ReplaceOne(ctx, filter, replacement, opts...)
	if err != nil {
		return nil, err
	}

	if err = mm.DelCache(ctx, key); err != nil {
		return nil, err
	}

	return res, nil
}

// ReplaceOneNoCache replaces a single document in the collection.
func (mm *Model) ReplaceOneNoCache(ctx context.Context, filter, replacement interface{},
	opts ...*mopt.ReplaceOptions) (*mongo.UpdateResult, error) {
	return mm.Model.ReplaceOne(ctx, filter, replacement, opts...)
}

// SetCache sets the cache with given key and value.
func (mm *Model) SetCache(key string, v interface{}) error {
	return mm.cache.Set(key, v)
}

// UpdateByID updates the document with given id with update, and remove the cache.
func (mm *Model) UpdateByID(ctx context.Context, key string, id, update interface{},
	opts ...*mopt.UpdateOptions) (*mongo.UpdateResult, error) {
	res, err := mm.Model.UpdateByID(ctx, id, update, opts...)
	if err != nil {
		return nil, err
	}

	if err = mm.DelCache(ctx, key); err != nil {
		return nil, err
	}

	return res, nil
}

// UpdateByIDNoCache updates the document with given id with update.
func (mm *Model) UpdateByIDNoCache(ctx context.Context, id, update interface{},
	opts ...*mopt.UpdateOptions) (*mongo.UpdateResult, error) {
	return mm.Model.UpdateByID(ctx, id, update, opts...)
}

// UpdateMany updates the documents that match filter with update, and remove the cache.
func (mm *Model) UpdateMany(ctx context.Context, keys []string, filter, update interface{},
	opts ...*mopt.UpdateOptions) (*mongo.UpdateResult, error) {
	res, err := mm.Model.UpdateMany(ctx, filter, update, opts...)
	if err != nil {
		return nil, err
	}

	if err = mm.DelCache(ctx, keys...); err != nil {
		return nil, err
	}

	return res, nil
}

// UpdateManyNoCache updates the documents that match filter with update.
func (mm *Model) UpdateManyNoCache(ctx context.Context, filter, update interface{},
	opts ...*mopt.UpdateOptions) (*mongo.UpdateResult, error) {
	return mm.Model.UpdateMany(ctx, filter, update, opts...)
}

// UpdateOne updates the first document that matches filter with update, and remove the cache.
func (mm *Model) UpdateOne(ctx context.Context, key string, filter, update interface{},
	opts ...*mopt.UpdateOptions) (*mongo.UpdateResult, error) {
	res, err := mm.Model.UpdateOne(ctx, filter, update, opts...)
	if err != nil {
		return nil, err
	}

	if err = mm.DelCache(ctx, key); err != nil {
		return nil, err
	}

	return res, nil
}

// UpdateOneNoCache updates the first document that matches filter with update.
func (mm *Model) UpdateOneNoCache(ctx context.Context, filter, update interface{},
	opts ...*mopt.UpdateOptions) (*mongo.UpdateResult, error) {
	return mm.Model.UpdateOne(ctx, filter, update, opts...)
}