vorteil/direktiv

package reconcile

// Item interface helps reconcile logic to identify objects and differences in lists.
type Item interface {
    GetID() string
    GetValueHash() string
}

type Result struct {
    Deletes []string
    Creates []string
    Updates []string
}

func Calculate(src []Item, target []Item) *Result {
    return &Result{
        Deletes: reconcileDelete(src, target),
        Creates: reconcileCreate(src, target),
        Updates: reconcileUpdate(src, target),
    }
}

func reconcileDelete(src []Item, target []Item) []string {
    result := []string{}
    search := map[string]bool{}
    for _, item := range src {
        search[item.GetID()] = true
    }
    for _, item := range target {
        _, ok := search[item.GetID()]
        if ok {
            continue
        }
        result = append(result, item.GetID())
    }

    return result
}

func reconcileCreate(src []Item, target []Item) []string {
    result := []string{}

    keys := map[string]bool{}
    for _, item := range target {
        keys[item.GetID()] = true
    }
    for _, item := range src {
        _, ok := keys[item.GetID()]
        if ok {
            continue
        }
        result = append(result, item.GetID())
    }

    return result
}

func reconcileUpdate(src []Item, target []Item) []string {
    result := []string{}

    search := map[string]Item{}
    for _, item := range src {
        search[item.GetID()] = item
    }

    for _, item := range target {
        searchItem, ok := search[item.GetID()]
        if !ok {
            continue
        }
        if searchItem.GetValueHash() == item.GetValueHash() {
            continue
        }
        result = append(result, item.GetID())
    }

    return result
}