package leaf

import (
	"context"
	"fmt"
	"time"

	"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"
)

type RepositoryInterface[T Document] interface {
	Collection() *mongo.Collection

	Find(ctx context.Context, filter interface{}, opts ...*options.FindOptions) ([]T, error)
	FindOne(ctx context.Context, filter interface{}, opts ...*options.FindOneOptions) (T, error)
	FindByID(ctx context.Context, id string, opts ...*options.FindOneOptions) (T, error)

	Create(ctx context.Context, data T, opts ...*options.InsertOneOptions) (T, error)

	Update(ctx context.Context, data T, opts ...*options.UpdateOptions) (T, error)
	UpdateOne(ctx context.Context, filter interface{}, data T, opts ...*options.UpdateOptions) (T, error)

	Delete(ctx context.Context, data T, opts ...*options.DeleteOptions) error
	DeleteOne(ctx context.Context, filter interface{}, opts ...*options.DeleteOptions) error

	CountDocuments(ctx context.Context, filter interface{}, opts ...*options.CountOptions) (int, error)
}

type Repository[T Document] struct {
	collection *mongo.Collection
	indexes    []mongo.IndexModel
}

func NewRepository[T Document](collection *mongo.Collection, indexes []mongo.IndexModel) *Repository[T] {
	return &Repository[T]{collection: collection, indexes: withTimestampIndexes(indexes)}
}

func (s *Repository[T]) Collection() *mongo.Collection {
	return s.collection
}

func (s *Repository[T]) Find(ctx context.Context, filter interface{}, opts ...*options.FindOptions) ([]T, error) {
	cursor, err := s.collection.Find(ctx, filter, opts...)
	if err != nil {
		return nil, repositoryError(s.collection, "Find", err)
	}
	defer cursor.Close(ctx)

	var data []T
	if err := cursor.All(ctx, &data); err != nil {
		return nil, repositoryError(s.collection, "Find", err)
	}

	return data, nil
}

func (s *Repository[T]) FindOne(ctx context.Context, filter interface{}, opts ...*options.FindOneOptions) (T, error) {
	var data T
	if err := s.collection.FindOne(ctx, filter, opts...).Decode(&data); err != nil {
		return data, repositoryError(s.collection, "FindOne", err)
	}

	return data, nil
}

func (s *Repository[T]) FindByID(ctx context.Context, id string, opts ...*options.FindOneOptions) (T, error) {
	return s.FindOne(ctx, bson.M{"_id": ObjectIDFromHex(id)}, opts...)
}

func (s *Repository[T]) Create(ctx context.Context, data T, opts ...*options.InsertOneOptions) (T, error) {
	data.SetCreatedAt(time.Now().UTC())
	data.SetUpdatedAt(time.Now().UTC())

	res, err := s.collection.InsertOne(ctx, data, opts...)
	if err != nil {
		return data, repositoryError(s.collection, "Create", err)
	}

	data.SetID(res.InsertedID.(primitive.ObjectID))
	return data, nil
}

func (s *Repository[T]) Update(ctx context.Context, data T, opts ...*options.UpdateOptions) (T, error) {
	return s.UpdateOne(ctx, bson.M{"_id": data.ID()}, data, opts...)
}

func (s *Repository[T]) UpdateOne(ctx context.Context, filter interface{}, data T, opts ...*options.UpdateOptions) (T, error) {
	data.SetUpdatedAt(time.Now().UTC())

	if _, err := s.collection.UpdateOne(ctx, filter, bson.M{"$set": data}, opts...); err != nil {
		return data, repositoryError(s.collection, "UpdateOne", err)
	}

	return data, nil
}

func (s *Repository[T]) Delete(ctx context.Context, data T, opts ...*options.DeleteOptions) error {
	return s.DeleteOne(ctx, bson.M{"_id": data.ID()}, opts...)
}

func (s *Repository[T]) DeleteOne(ctx context.Context, filter interface{}, opts ...*options.DeleteOptions) error {
	if _, err := s.collection.DeleteOne(ctx, filter, opts...); err != nil {
		return repositoryError(s.collection, "DeleteOne", err)
	}

	return nil
}

func (s *Repository[T]) CountDocuments(ctx context.Context, filter interface{}, opts ...*options.CountOptions) (int, error) {
	count, err := s.collection.CountDocuments(ctx, filter, opts...)
	return int(count), err
}

func (s *Repository[T]) EnsureIndexes(ctx context.Context, createIndexes bool) ([]IndexMessage, error) {
	return ensureIndexes(ctx, s.collection, s.indexes, createIndexes)
}

func repositoryError(collection *mongo.Collection, op string, err error) error {
	return fmt.Errorf("%s.%s: %v", collection.Name(), op, err)
}