package filer

import (
	"context"
	"os"
	"testing"

	"github.com/seaweedfs/seaweedfs/weed/pb"
	"github.com/seaweedfs/seaweedfs/weed/util"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
)

func newTestFilerWithStubStore() (*Filer, *stubFilerStore) {
	store := newStubFilerStore()
	f := NewFiler(pb.ServerDiscovery{}, nil, "", "", "", "", "", 255, nil)
	f.Store = NewFilerStoreWrapper(store)
	return f, store
}

func TestCreateEntryAssignsInodeWhenMissing(t *testing.T) {
	f, store := newTestFilerWithStubStore()

	entry := &Entry{
		FullPath: util.FullPath("/dir/file.txt"),
		Attr: Attr{
			Mode: 0o644,
		},
	}

	err := f.CreateEntry(context.Background(), entry, false, false, nil, false, f.MaxFilenameLength)
	require.NoError(t, err)

	stored, findErr := store.FindEntry(context.Background(), entry.FullPath)
	require.NoError(t, findErr)
	require.NotNil(t, stored)
	assert.NotZero(t, stored.Attr.Inode)
	assert.NotEqual(t, uint64(1), stored.Attr.Inode)
}

func TestCreateEntryAssignsInodesToAutoCreatedParents(t *testing.T) {
	f, store := newTestFilerWithStubStore()

	entry := &Entry{
		FullPath: util.FullPath("/a/b/c.txt"),
		Attr: Attr{
			Mode: 0o644,
		},
	}

	err := f.CreateEntry(context.Background(), entry, false, false, nil, false, f.MaxFilenameLength)
	require.NoError(t, err)

	for _, path := range []string{"/a", "/a/b", "/a/b/c.txt"} {
		stored, findErr := store.FindEntry(context.Background(), util.FullPath(path))
		require.NoError(t, findErr, path)
		require.NotNil(t, stored, path)
		assert.NotZero(t, stored.Attr.Inode, path)
	}
}

func TestUpdateEntryPreservesExistingInode(t *testing.T) {
	f, store := newTestFilerWithStubStore()

	original := &Entry{
		FullPath: util.FullPath("/doc.txt"),
		Attr: Attr{
			Mode:  0o644,
			Inode: 12345,
		},
	}
	require.NoError(t, store.InsertEntry(context.Background(), original))

	updated := &Entry{
		FullPath: util.FullPath("/doc.txt"),
		Attr: Attr{
			Mode: os.ModeDir | 0o755,
		},
	}

	err := f.UpdateEntry(context.Background(), original, updated)
	require.Error(t, err)

	updated = &Entry{
		FullPath: util.FullPath("/doc.txt"),
		Attr: Attr{
			Mode: 0o600,
		},
	}
	err = f.UpdateEntry(context.Background(), original, updated)
	require.NoError(t, err)

	stored, findErr := store.FindEntry(context.Background(), original.FullPath)
	require.NoError(t, findErr)
	require.NotNil(t, stored)
	assert.Equal(t, uint64(12345), stored.Attr.Inode)
}

func TestUpdateEntryBackfillsMissingLegacyInode(t *testing.T) {
	f, store := newTestFilerWithStubStore()

	original := &Entry{
		FullPath: util.FullPath("/legacy.txt"),
		Attr: Attr{
			Mode: 0o644,
		},
	}
	require.NoError(t, store.InsertEntry(context.Background(), original))

	updated := &Entry{
		FullPath: util.FullPath("/legacy.txt"),
		Attr: Attr{
			Mode: 0o640,
		},
	}
	err := f.UpdateEntry(context.Background(), original, updated)
	require.NoError(t, err)

	stored, findErr := store.FindEntry(context.Background(), original.FullPath)
	require.NoError(t, findErr)
	require.NotNil(t, stored)
	assert.NotZero(t, stored.Attr.Inode)
	assert.NotEqual(t, uint64(1), stored.Attr.Inode)
}