package wmo

import (
	"context"
	"errors"
	"go.mongodb.org/mongo-driver/mongo"
	"go.mongodb.org/mongo-driver/mongo/options"
)

func (c *Coll[TData]) Aggregate(ctx context.Context, pipeline mongo.Pipeline, opts ...*options.AggregateOptions) ([]TData, error) {
	cursor, err := c.coll.Aggregate(ctx, pipeline, opts...)
	if err != nil {
		return nil, err
	}

	res, err := c.decodeAll(ctx, cursor)
	if err != nil {
		return nil, err
	}

	return res, nil
}

func (c *Coll[TData]) AggregateOneOpt(ctx context.Context, pipeline mongo.Pipeline, opts ...*options.AggregateOptions) (*TData, error) {
	cursor, err := c.coll.Aggregate(ctx, pipeline, opts...)
	if err != nil {
		return nil, err
	}

	if cursor.Next(ctx) {
		v, err := c.decodeSingle(ctx, cursor)
		if err != nil {
			return nil, err
		}
		return &v, nil
	}

	return nil, nil
}

func (c *Coll[TData]) AggregateOne(ctx context.Context, pipeline mongo.Pipeline, opts ...*options.AggregateOptions) (TData, error) {
	cursor, err := c.coll.Aggregate(ctx, pipeline, opts...)
	if err != nil {
		return *new(TData), err
	}

	if cursor.Next(ctx) {
		v, err := c.decodeSingle(ctx, cursor)
		if err != nil {
			return *new(TData), err
		}
		return v, nil
	}

	return *new(TData), errors.New("no document in result")
}