Fantom-foundation/go-lachesis

package inter

import (
    "strings"

    "github.com/Fantom-foundation/go-lachesis/hash"
)

// Events is a ordered slice of events.
type Events []*Event

// String returns human readable representation.
func (ee Events) String() string {
    ss := make([]string, len(ee))
    for i := 0; i < len(ee); i++ {
        ss[i] = ee[i].String()
    }
    return strings.Join(ss, " ")
}

// ByParents returns events topologically ordered by parent dependency.
// Used only for tests.
func (ee Events) ByParents() (res Events) {
    unsorted := make(Events, len(ee))
    exists := hash.EventsSet{}
    for i, e := range ee {
        unsorted[i] = e
        exists.Add(e.Hash())
    }
    ready := hash.EventsSet{}
    for len(unsorted) > 0 {
    EVENTS:
        for i, e := range unsorted {

            for _, p := range e.Parents {
                if exists.Contains(p) && !ready.Contains(p) {
                    continue EVENTS
                }
            }

            res = append(res, e)
            unsorted = append(unsorted[0:i], unsorted[i+1:]...)
            ready.Add(e.Hash())
            break
        }
    }

    return
}