package db

import (
	"errors"
	"testing"
)

func TestDeleteManifest(t *testing.T) {
	d := openTestDB(t)
	if err := d.Migrate(); err != nil {
		t.Fatalf("Migrate: %v", err)
	}

	// Set up repo, manifest, tag, blob, manifest_blob.
	_, err := d.Exec(`INSERT INTO repositories (name) VALUES ('testrepo')`)
	if err != nil {
		t.Fatalf("insert repo: %v", err)
	}
	_, err = d.Exec(`INSERT INTO manifests (repository_id, digest, media_type, content, size)
		VALUES (1, 'sha256:m1', 'application/vnd.oci.image.manifest.v1+json', '{}', 2)`)
	if err != nil {
		t.Fatalf("insert manifest: %v", err)
	}
	_, err = d.Exec(`INSERT INTO tags (repository_id, name, manifest_id) VALUES (1, 'latest', 1)`)
	if err != nil {
		t.Fatalf("insert tag: %v", err)
	}
	_, err = d.Exec(`INSERT INTO blobs (digest, size) VALUES ('sha256:b1', 100)`)
	if err != nil {
		t.Fatalf("insert blob: %v", err)
	}
	_, err = d.Exec(`INSERT INTO manifest_blobs (manifest_id, blob_id) VALUES (1, 1)`)
	if err != nil {
		t.Fatalf("insert manifest_blob: %v", err)
	}

	// Delete the manifest.
	if err := d.DeleteManifest(1, "sha256:m1"); err != nil {
		t.Fatalf("DeleteManifest: %v", err)
	}

	// Verify manifest is gone.
	_, err = d.GetManifestByDigest(1, "sha256:m1")
	if !errors.Is(err, ErrManifestNotFound) {
		t.Fatalf("expected ErrManifestNotFound, got %v", err)
	}

	// Verify tag was cascaded.
	var tagCount int
	if err := d.QueryRow(`SELECT COUNT(*) FROM tags`).Scan(&tagCount); err != nil {
		t.Fatalf("count tags: %v", err)
	}
	if tagCount != 0 {
		t.Fatalf("tag count: got %d, want 0", tagCount)
	}

	// Verify manifest_blobs was cascaded.
	var mbCount int
	if err := d.QueryRow(`SELECT COUNT(*) FROM manifest_blobs`).Scan(&mbCount); err != nil {
		t.Fatalf("count manifest_blobs: %v", err)
	}
	if mbCount != 0 {
		t.Fatalf("manifest_blobs count: got %d, want 0", mbCount)
	}

	// Verify blob row still exists (GC handles file cleanup).
	var blobCount int
	if err := d.QueryRow(`SELECT COUNT(*) FROM blobs`).Scan(&blobCount); err != nil {
		t.Fatalf("count blobs: %v", err)
	}
	if blobCount != 1 {
		t.Fatalf("blob count: got %d, want 1 (should not be deleted)", blobCount)
	}
}

func TestDeleteManifestNotFound(t *testing.T) {
	d := openTestDB(t)
	if err := d.Migrate(); err != nil {
		t.Fatalf("Migrate: %v", err)
	}

	_, err := d.Exec(`INSERT INTO repositories (name) VALUES ('testrepo')`)
	if err != nil {
		t.Fatalf("insert repo: %v", err)
	}

	err = d.DeleteManifest(1, "sha256:nonexistent")
	if !errors.Is(err, ErrManifestNotFound) {
		t.Fatalf("expected ErrManifestNotFound, got %v", err)
	}
}

func TestDeleteBlobFromRepo(t *testing.T) {
	d := openTestDB(t)
	if err := d.Migrate(); err != nil {
		t.Fatalf("Migrate: %v", err)
	}

	// Set up: repo, manifest, blob, manifest_blob.
	_, err := d.Exec(`INSERT INTO repositories (name) VALUES ('testrepo')`)
	if err != nil {
		t.Fatalf("insert repo: %v", err)
	}
	_, err = d.Exec(`INSERT INTO manifests (repository_id, digest, media_type, content, size)
		VALUES (1, 'sha256:m1', 'application/vnd.oci.image.manifest.v1+json', '{}', 2)`)
	if err != nil {
		t.Fatalf("insert manifest: %v", err)
	}
	_, err = d.Exec(`INSERT INTO blobs (digest, size) VALUES ('sha256:b1', 100)`)
	if err != nil {
		t.Fatalf("insert blob: %v", err)
	}
	_, err = d.Exec(`INSERT INTO manifest_blobs (manifest_id, blob_id) VALUES (1, 1)`)
	if err != nil {
		t.Fatalf("insert manifest_blob: %v", err)
	}

	// Delete blob from repo.
	if err := d.DeleteBlobFromRepo(1, "sha256:b1"); err != nil {
		t.Fatalf("DeleteBlobFromRepo: %v", err)
	}

	// Verify manifest_blobs is gone.
	var mbCount int
	if err := d.QueryRow(`SELECT COUNT(*) FROM manifest_blobs`).Scan(&mbCount); err != nil {
		t.Fatalf("count manifest_blobs: %v", err)
	}
	if mbCount != 0 {
		t.Fatalf("manifest_blobs count: got %d, want 0", mbCount)
	}

	// Verify blob row still exists (GC responsibility).
	var blobCount int
	if err := d.QueryRow(`SELECT COUNT(*) FROM blobs`).Scan(&blobCount); err != nil {
		t.Fatalf("count blobs: %v", err)
	}
	if blobCount != 1 {
		t.Fatalf("blob count: got %d, want 1", blobCount)
	}

	// Verify manifest still exists.
	var mCount int
	if err := d.QueryRow(`SELECT COUNT(*) FROM manifests`).Scan(&mCount); err != nil {
		t.Fatalf("count manifests: %v", err)
	}
	if mCount != 1 {
		t.Fatalf("manifest count: got %d, want 1", mCount)
	}
}

func TestDeleteBlobFromRepoNotFound(t *testing.T) {
	d := openTestDB(t)
	if err := d.Migrate(); err != nil {
		t.Fatalf("Migrate: %v", err)
	}

	_, err := d.Exec(`INSERT INTO repositories (name) VALUES ('testrepo')`)
	if err != nil {
		t.Fatalf("insert repo: %v", err)
	}

	// Blob doesn't exist at all.
	err = d.DeleteBlobFromRepo(1, "sha256:nonexistent")
	if !errors.Is(err, ErrBlobNotFound) {
		t.Fatalf("expected ErrBlobNotFound, got %v", err)
	}
}

func TestDeleteBlobFromRepoExistsGloballyButNotInRepo(t *testing.T) {
	d := openTestDB(t)
	if err := d.Migrate(); err != nil {
		t.Fatalf("Migrate: %v", err)
	}

	// Two repos: blob only referenced in repo 2.
	_, err := d.Exec(`INSERT INTO repositories (name) VALUES ('repo1')`)
	if err != nil {
		t.Fatalf("insert repo1: %v", err)
	}
	_, err = d.Exec(`INSERT INTO repositories (name) VALUES ('repo2')`)
	if err != nil {
		t.Fatalf("insert repo2: %v", err)
	}
	_, err = d.Exec(`INSERT INTO manifests (repository_id, digest, media_type, content, size)
		VALUES (2, 'sha256:m2', 'application/vnd.oci.image.manifest.v1+json', '{}', 2)`)
	if err != nil {
		t.Fatalf("insert manifest: %v", err)
	}
	_, err = d.Exec(`INSERT INTO blobs (digest, size) VALUES ('sha256:shared', 500)`)
	if err != nil {
		t.Fatalf("insert blob: %v", err)
	}
	_, err = d.Exec(`INSERT INTO manifest_blobs (manifest_id, blob_id) VALUES (1, 1)`)
	if err != nil {
		t.Fatalf("insert manifest_blob: %v", err)
	}

	// Try to delete from repo1 — blob exists globally but not in repo1.
	err = d.DeleteBlobFromRepo(1, "sha256:shared")
	if !errors.Is(err, ErrBlobNotFound) {
		t.Fatalf("expected ErrBlobNotFound for blob not in repo1, got %v", err)
	}
}