package photos

import (
	"context"
	"testing"
	"time"
)

func TestCopySharesStorageObjects(t *testing.T) {
	pool := testPool(t)
	ctx := context.Background()
	svc, cl := newTestService(t, pool)
	user := createUser(t, ctx, pool)
	albumA := createAlbum(t, ctx, pool, user)
	albumB := createAlbum(t, ctx, pool, user)

	p, err := svc.Upload(ctx, UploadInput{
		AlbumID: albumA, UserID: user, Filename: "p.png", MimeType: "image/png", Data: makePNG(t),
	})
	if err != nil {
		t.Fatalf("upload: %v", err)
	}
	t.Cleanup(func() { cleanupPhoto(t, ctx, pool, cl, p.ID) })

	w := NewWorker(svc, time.Second, 10, time.Minute, 2)
	w.processVariantJobs(ctx)

	srcIDs, err := svc.store.PhotoObjectIDs(ctx, p.ID)
	if err != nil || len(srcIDs) != 3 {
		t.Fatalf("source objects = %v err=%v", srcIDs, err)
	}

	clones, err := svc.CopyBatch(ctx, []string{p.ID}, user, albumB)
	if err != nil || len(clones) != 1 {
		t.Fatalf("copy: %v len=%d", err, len(clones))
	}
	clone := clones[0]
	t.Cleanup(func() { cleanupPhoto(t, ctx, pool, cl, clone.ID) })

	cloneIDs, err := svc.store.PhotoObjectIDs(ctx, clone.ID)
	if err != nil || len(cloneIDs) != 3 {
		t.Fatalf("clone objects = %v err=%v", cloneIDs, err)
	}
	if !sameSet(srcIDs, cloneIDs) {
		t.Fatalf("clone does not share objects: src=%v clone=%v", srcIDs, cloneIDs)
	}
	for _, id := range cloneIDs {
		if n, err := svc.store.ObjectRefCount(ctx, id); err != nil || n != 2 {
			t.Fatalf("object %s ref count = %d err=%v, want 2", id, n, err)
		}
	}

	// Move the source into the same album; the storage key and shared objects
	// must be untouched.
	beforeKey := p.StorageKey
	moved, err := svc.MoveBatch(ctx, []string{p.ID}, user, albumB)
	if err != nil || moved != 1 {
		t.Fatalf("move: %v moved=%d", err, moved)
	}
	after, err := svc.store.GetByID(ctx, p.ID, "")
	if err != nil {
		t.Fatalf("get after move: %v", err)
	}
	if after.AlbumID != albumB {
		t.Fatalf("photo not moved: album=%q", after.AlbumID)
	}
	if after.StorageKey != beforeKey {
		t.Fatalf("move changed storage key: %q -> %q", beforeKey, after.StorageKey)
	}
	for _, id := range cloneIDs {
		if n, err := svc.store.ObjectRefCount(ctx, id); err != nil || n != 2 {
			t.Fatalf("object %s ref count after move = %d err=%v, want 2", id, n, err)
		}
	}
}

func sameSet(a, b []string) bool {
	if len(a) != len(b) {
		return false
	}
	m := make(map[string]int, len(a))
	for _, v := range a {
		m[v]++
	}
	for _, v := range b {
		m[v]--
		if m[v] < 0 {
			return false
		}
	}
	return true
}