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package helpers

import (
	"bytes"
	"github.com/go-git/go-git/v5"
	"github.com/go-git/go-git/v5/plumbing"
	"github.com/go-git/go-git/v5/utils/merkletrie/noder"
)

// https://github.com/go-git/go-git/blob/bf3471db54b0255ab5b159005069f37528a151b7/worktree_status.go#L242-L259
var emptyNoderHash = make([]byte, 24)

func diffTreeIsEquals(a, b noder.Hasher) bool {
	hashA := a.Hash()
	hashB := b.Hash()

	if bytes.Equal(hashA, emptyNoderHash) || bytes.Equal(hashB, emptyNoderHash) {
		return false
	}

	return bytes.Equal(hashA, hashB)
}

// https://github.com/go-git/go-git/blob/bf3471db54b0255ab5b159005069f37528a151b7/worktree_status.go#L180-L203
func getSubmodulesStatus(w *git.Worktree) (map[string]plumbing.Hash, error) {
	o := map[string]plumbing.Hash{}

	sub, err := w.Submodules()
	if err != nil {
		return nil, err
	}

	status, err := sub.Status()
	if err != nil {
		return nil, err
	}

	for _, s := range status {
		if s.Current.IsZero() {
			o[s.Path] = s.Expected
			continue
		}

		o[s.Path] = s.Current
	}

	return o, nil
}
