package clauses

import (
	"context"
	"github.com/MontFerret/ferret/pkg/runtime/collections"
	"github.com/MontFerret/ferret/pkg/runtime/core"
)

type LimitClause struct {
	*baseClause
	count  int
	offset int
}

func NewLimitClause(
	src core.SourceMap,
	dataSource collections.IterableExpression,
	count int,
	offset int,
) *LimitClause {
	return &LimitClause{&baseClause{src, dataSource}, count, offset}
}

func (clause *LimitClause) Iterate(ctx context.Context, scope *core.Scope) (collections.Iterator, error) {
	src, err := clause.dataSource.Iterate(ctx, scope)

	if err != nil {
		return nil, err
	}

	return collections.NewLimitIterator(src, clause.count, clause.offset)
}