package oci

import (
	"errors"
	"fmt"
	"net/http"

	"git.wntrmute.dev/kyle/mcr/internal/db"
	"git.wntrmute.dev/kyle/mcr/internal/policy"
)

// handleManifestDelete handles DELETE /v2/<name>/manifests/<digest>.
// Per OCI spec, deletion by tag is not supported — only by digest.
func (h *Handler) handleManifestDelete(w http.ResponseWriter, r *http.Request, repo, reference string) {
	if !h.checkPolicy(w, r, policy.ActionDelete, repo) {
		return
	}

	// Reference must be a digest, not a tag.
	if !isDigest(reference) {
		writeOCIError(w, "UNSUPPORTED", http.StatusMethodNotAllowed,
			"manifest deletion by tag is not supported; use digest")
		return
	}

	repoID, err := h.db.GetRepositoryByName(repo)
	if err != nil {
		if errors.Is(err, db.ErrRepoNotFound) {
			writeOCIError(w, "NAME_UNKNOWN", http.StatusNotFound,
				fmt.Sprintf("repository %q not found", repo))
			return
		}
		writeOCIError(w, "UNKNOWN", http.StatusInternalServerError, "internal error")
		return
	}

	if err := h.db.DeleteManifest(repoID, reference); err != nil {
		if errors.Is(err, db.ErrManifestNotFound) {
			writeOCIError(w, "MANIFEST_UNKNOWN", http.StatusNotFound,
				fmt.Sprintf("manifest %q not found", reference))
			return
		}
		writeOCIError(w, "UNKNOWN", http.StatusInternalServerError, "internal error")
		return
	}

	h.audit(r, "manifest_deleted", repo, reference)

	w.WriteHeader(http.StatusAccepted)
}

// handleBlobDelete handles DELETE /v2/<name>/blobs/<digest>.
// Removes manifest_blobs associations for this repo only. Does not delete
// the blob row or file — that is GC's responsibility.
func (h *Handler) handleBlobDelete(w http.ResponseWriter, r *http.Request, repo, digest string) {
	if !h.checkPolicy(w, r, policy.ActionDelete, repo) {
		return
	}

	repoID, err := h.db.GetRepositoryByName(repo)
	if err != nil {
		if errors.Is(err, db.ErrRepoNotFound) {
			writeOCIError(w, "NAME_UNKNOWN", http.StatusNotFound,
				fmt.Sprintf("repository %q not found", repo))
			return
		}
		writeOCIError(w, "UNKNOWN", http.StatusInternalServerError, "internal error")
		return
	}

	if err := h.db.DeleteBlobFromRepo(repoID, digest); err != nil {
		if errors.Is(err, db.ErrBlobNotFound) {
			writeOCIError(w, "BLOB_UNKNOWN", http.StatusNotFound,
				fmt.Sprintf("blob %q not found in repository", digest))
			return
		}
		writeOCIError(w, "UNKNOWN", http.StatusInternalServerError, "internal error")
		return
	}

	h.audit(r, "blob_deleted", repo, digest)

	w.WriteHeader(http.StatusAccepted)
}