delete.go

// SPDX-License-Identifier: Apache-2.0

package manifestedit

// EditDeleted means a document was removed from the file.
const EditDeleted EditMode = "deleted"

// DeleteResult is the outcome of removing one document from a file.
type DeleteResult struct {
	// Content is the file content after removal. It is nil when FileEmpty is true.
	Content []byte
	// FileEmpty is true when the removed document was the only one, so the caller
	// should delete the file rather than write empty content.
	FileEmpty bool
	Mode      EditMode
}

// DeleteDocument removes one document from a file, leaving every surviving
// document's content byte-for-byte intact. Removing the only document reports
// FileEmpty so the caller can delete the file. This serves both resource deletion
// and pruning a duplicate loser.
//
// It is a thin wrapper over Decide + Apply with Desired == nil. Deletion is the
// content-agnostic cell of the comparison: it never decrypts or merges, so an
// encrypted document, a disallowed-construct document, or a duplicate loser can
// always be pruned. No renderer is needed.
//
// When the first document is removed, the new first document's leading "---"
// separator is dropped so the file does not start with a stray separator. Only
// the separator is affected; the document content is unchanged. We deliberately
// prefer a clean leading document over preserving a now-pointless separator.
func DeleteDocument(content []byte, documentIndex int) (DeleteResult, []Diagnostic) {
	git, _ := NewDocument(content, documentIndex)
	c := Comparison{Git: git, Desired: nil}
	res, diags := Apply(c, Decide(c))

	if res.Mode != EditDeleted {
		return DeleteResult{Content: content, Mode: res.Mode}, diags
	}
	if len(res.Content) == 0 {
		return DeleteResult{FileEmpty: true, Mode: EditDeleted}, diags
	}
	return DeleteResult{Content: res.Content, Mode: EditDeleted}, diags
}