Function ResolveHeadTime

engine/temporal.go:497–516

ResolveHeadTime resolves variables and special bounds (like 'now') in a HeadTime interval using the given substitution. Returns the resolved interval or nil if HeadTime is nil.

(headTime *ast.Interval, subst unionfind.UnionFind, evalTime time.Time)

// ResolveHeadTime resolves variables and special bounds (like 'now') in a HeadTime interval
// using the given substitution. Returns the resolved interval or nil if HeadTime is nil.
func ResolveHeadTime(headTime *ast.Interval, subst unionfind.UnionFind, evalTime time.Time) (*ast.Interval, error) {
	if headTime == nil {
		return nil, nil
	}

	// Resolve start bound
	start, err := resolveBoundWithSubst(headTime.Start, subst, evalTime)
	if err != nil {
		return nil, fmt.Errorf("failed to resolve start bound: %w", err)
	}

	// Resolve end bound
	end, err := resolveBoundWithSubst(headTime.End, subst, evalTime)
	if err != nil {
		return nil, fmt.Errorf("failed to resolve end bound: %w", err)
	}

	resolved := ast.NewInterval(start, end)
	return &resolved, nil
}

// resolveBoundWithSubst resolves a temporal bound, substituting variables and handling 'now'.
func resolveBoundWithSubst(bound ast.TemporalBound, subst unionfind.UnionFind, evalTime time.Time) (ast.TemporalBound, error) {