// Copyright 2015 The Vanadium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package mounttablelib

import (
	"errors"
	"fmt"
	"io"
	"reflect"
	"runtime/debug"
	"sort"
	"testing"
	"time"

	"v.io/v23"
	"v.io/v23/context"
	"v.io/v23/naming"
	"v.io/v23/options"
	"v.io/v23/rpc"
	"v.io/v23/security"
	"v.io/v23/security/access"
	"v.io/v23/services/stats"
	"v.io/v23/vdl"
	"v.io/x/lib/vlog"

	"v.io/x/ref/services/debug/debuglib"
	"v.io/x/ref/test"
	"v.io/x/ref/test/testutil"
)

// Simulate different processes with different runtimes.
// rootCtx is the one running the mounttable service.
const ttlSecs = 60 * 60

func boom(t *testing.T, f string, v ...interface{}) {
	t.Logf(f, v...)
	t.Fatal(string(debug.Stack()))
}

func doMount(t *testing.T, ctx *context.T, ep, suffix, service string, shouldSucceed bool) {
	name := naming.JoinAddressName(ep, suffix)
	client := v23.GetClient(ctx)
	if err := client.Call(ctx, name, "Mount", []interface{}{service, uint32(ttlSecs), 0}, nil, options.NoResolve{}); err != nil {
		if !shouldSucceed {
			return
		}
		boom(t, "Failed to Mount %s onto %s: %s", service, name, err)
	}
}

func doUnmount(t *testing.T, ctx *context.T, ep, suffix, service string, shouldSucceed bool) {
	name := naming.JoinAddressName(ep, suffix)
	client := v23.GetClient(ctx)
	if err := client.Call(ctx, name, "Unmount", []interface{}{service}, nil, options.NoResolve{}); err != nil {
		if !shouldSucceed {
			return
		}
		boom(t, "Failed to Unmount %s off of %s: %s", service, name, err)
	}
}

func doGetPermissions(t *testing.T, ctx *context.T, ep, suffix string, shouldSucceed bool) (perms access.Permissions, version string) {
	name := naming.JoinAddressName(ep, suffix)
	client := v23.GetClient(ctx)
	if err := client.Call(ctx, name, "GetPermissions", nil, []interface{}{&perms, &version}, options.NoResolve{}); err != nil {
		if !shouldSucceed {
			return
		}
		boom(t, "Failed to GetPermissions %s: %s", name, err)
	}
	return
}

func doSetPermissions(t *testing.T, ctx *context.T, ep, suffix string, perms access.Permissions, version string, shouldSucceed bool) {
	name := naming.JoinAddressName(ep, suffix)
	client := v23.GetClient(ctx)
	if err := client.Call(ctx, name, "SetPermissions", []interface{}{perms, version}, nil, options.NoResolve{}); err != nil {
		if !shouldSucceed {
			return
		}
		boom(t, "Failed to SetPermissions %s: %s", name, err)
	}
}

func doDeleteNode(t *testing.T, ctx *context.T, ep, suffix string, shouldSucceed bool) {
	name := naming.JoinAddressName(ep, suffix)
	client := v23.GetClient(ctx)
	if err := client.Call(ctx, name, "Delete", []interface{}{false}, nil, options.NoResolve{}); err != nil {
		if !shouldSucceed {
			return
		}
		boom(t, "Failed to Delete node %s: %s", name, err)
	}
}

func doDeleteSubtree(t *testing.T, ctx *context.T, ep, suffix string, shouldSucceed bool) {
	name := naming.JoinAddressName(ep, suffix)
	client := v23.GetClient(ctx)
	if err := client.Call(ctx, name, "Delete", []interface{}{true}, nil, options.NoResolve{}); err != nil {
		if !shouldSucceed {
			return
		}
		boom(t, "Failed to Delete subtree %s: %s", name, err)
	}
}

func mountentry2names(e *naming.MountEntry) []string {
	names := make([]string, len(e.Servers))
	for idx, s := range e.Servers {
		names[idx] = naming.JoinAddressName(s.Server, e.Name)
	}
	return names
}

func strslice(strs ...string) []string {
	return strs
}

func resolve(ctx *context.T, name string) (*naming.MountEntry, error) {
	// Resolve the name one level.
	var entry naming.MountEntry
	client := v23.GetClient(ctx)
	if err := client.Call(ctx, name, "ResolveStep", nil, []interface{}{&entry}, options.NoResolve{}); err != nil {
		return nil, err
	}
	if len(entry.Servers) < 1 {
		return nil, errors.New("resolve returned no servers")
	}
	return &entry, nil
}

func export(t *testing.T, ctx *context.T, name, contents string) {
	// Resolve the name.
	resolved, err := resolve(ctx, name)
	if err != nil {
		boom(t, "Failed to Export.Resolve %s: %s", name, err)
	}
	// Export the value.
	client := v23.GetClient(ctx)
	if err := client.Call(ctx, mountentry2names(resolved)[0], "Export", []interface{}{contents, true}, nil, options.NoResolve{}); err != nil {
		boom(t, "Failed to Export.Call %s to %s: %s", name, contents, err)
	}
}

func checkContents(t *testing.T, ctx *context.T, name, expected string, shouldSucceed bool) {
	// Resolve the name.
	resolved, err := resolve(ctx, name)
	if err != nil {
		if !shouldSucceed {
			return
		}
		boom(t, "Failed to Resolve %s: %s", name, err)
	}
	// Look up the value.
	client := v23.GetClient(ctx)
	call, err := client.StartCall(ctx, mountentry2names(resolved)[0], "Lookup", nil, options.NoResolve{})
	if err != nil {
		if shouldSucceed {
			boom(t, "Failed Lookup.StartCall %s: %s", name, err)
		}
		return
	}
	var contents []byte
	if err := call.Finish(&contents); err != nil {
		if shouldSucceed {
			boom(t, "Failed to Lookup %s: %s", name, err)
		}
		return
	}
	if string(contents) != expected {
		boom(t, "Lookup %s, expected %q, got %q", name, expected, contents)
	}
	if !shouldSucceed {
		boom(t, "Lookup %s, expected failure, got %q", name, contents)
	}
}

func newMT(t *testing.T, permsFile, persistDir string, rootCtx *context.T) (rpc.Server, string) {
	reservedDisp := debuglib.NewDispatcher(vlog.Log.LogDir, nil)
	ctx := v23.WithReservedNameDispatcher(rootCtx, reservedDisp)
	server, err := v23.NewServer(ctx, options.ServesMountTable(true))
	if err != nil {
		boom(t, "r.NewServer: %s", err)
	}
	// Add mount table service.
	mt, err := NewMountTableDispatcher(permsFile, persistDir, "mounttable")
	if err != nil {
		boom(t, "NewMountTableDispatcher: %v", err)
	}
	// Start serving on a loopback address.
	eps, err := server.Listen(v23.GetListenSpec(ctx))
	if err != nil {
		boom(t, "Failed to Listen mount table: %s", err)
	}
	if err := server.ServeDispatcher("", mt); err != nil {
		boom(t, "Failed to register mock collection: %s", err)
	}
	estr := eps[0].String()
	t.Logf("endpoint %s", estr)
	return server, estr
}

func newCollection(t *testing.T, rootCtx *context.T) (rpc.Server, string) {
	server, err := v23.NewServer(rootCtx)
	if err != nil {
		boom(t, "r.NewServer: %s", err)
	}
	// Start serving on a loopback address.
	eps, err := server.Listen(v23.GetListenSpec(rootCtx))
	if err != nil {
		boom(t, "Failed to Listen mount table: %s", err)
	}
	// Add a collection service.  This is just a service we can mount
	// and test against.
	cPrefix := "collection"
	if err := server.ServeDispatcher(cPrefix, newCollectionServer()); err != nil {
		boom(t, "Failed to register mock collection: %s", err)
	}
	estr := eps[0].String()
	t.Logf("endpoint %s", estr)
	return server, estr
}

func TestMountTable(t *testing.T) {
	rootCtx, aliceCtx, bobCtx, shutdown := initTest()
	defer shutdown()

	mt, mtAddr := newMT(t, "testdata/test.perms", "", rootCtx)
	defer mt.Stop()
	collection, collectionAddr := newCollection(t, rootCtx)
	defer collection.Stop()

	collectionName := naming.JoinAddressName(collectionAddr, "collection")

	// Mount the collection server into the mount table.
	vlog.Infof("Mount the collection server into the mount table.")
	doMount(t, rootCtx, mtAddr, "stuff", collectionName, true)

	// Create a few objects and make sure we can read them.
	vlog.Infof("Create a few objects.")
	export(t, rootCtx, naming.JoinAddressName(mtAddr, "stuff/the/rain"), "the rain")
	export(t, rootCtx, naming.JoinAddressName(mtAddr, "stuff/in/spain"), "in spain")
	export(t, rootCtx, naming.JoinAddressName(mtAddr, "stuff/falls"), "falls mainly on the plain")
	vlog.Infof("Make sure we can read them.")
	checkContents(t, rootCtx, naming.JoinAddressName(mtAddr, "stuff/the/rain"), "the rain", true)
	checkContents(t, rootCtx, naming.JoinAddressName(mtAddr, "stuff/in/spain"), "in spain", true)
	checkContents(t, rootCtx, naming.JoinAddressName(mtAddr, "stuff/falls"), "falls mainly on the plain", true)
	checkContents(t, rootCtx, naming.JoinAddressName(mtAddr, "/stuff/falls"), "falls mainly on the plain", true)
	checkContents(t, rootCtx, naming.JoinAddressName(mtAddr, "stuff/nonexistant"), "falls mainly on the plain", false)
	checkContents(t, bobCtx, naming.JoinAddressName(mtAddr, "stuff/the/rain"), "the rain", true)
	checkContents(t, aliceCtx, naming.JoinAddressName(mtAddr, "stuff/the/rain"), "the rain", false)

	// Test multiple mounts.
	vlog.Infof("Multiple mounts.")
	doMount(t, rootCtx, mtAddr, "a/b", collectionName, true)
	doMount(t, rootCtx, mtAddr, "x/y", collectionName, true)
	doMount(t, rootCtx, mtAddr, "alpha//beta", collectionName, true)
	vlog.Infof("Make sure we can read them.")
	checkContents(t, rootCtx, naming.JoinAddressName(mtAddr, "stuff/falls"), "falls mainly on the plain", true)
	checkContents(t, rootCtx, naming.JoinAddressName(mtAddr, "a/b/falls"), "falls mainly on the plain", true)
	checkContents(t, rootCtx, naming.JoinAddressName(mtAddr, "x/y/falls"), "falls mainly on the plain", true)
	checkContents(t, rootCtx, naming.JoinAddressName(mtAddr, "alpha/beta/falls"), "falls mainly on the plain", true)
	checkContents(t, aliceCtx, naming.JoinAddressName(mtAddr, "a/b/falls"), "falls mainly on the plain", true)
	checkContents(t, bobCtx, naming.JoinAddressName(mtAddr, "a/b/falls"), "falls mainly on the plain", false)

	// Test getting/setting AccessLists.
	perms, version := doGetPermissions(t, rootCtx, mtAddr, "stuff", true)
	doSetPermissions(t, rootCtx, mtAddr, "stuff", perms, "xyzzy", false) // bad version
	doSetPermissions(t, rootCtx, mtAddr, "stuff", perms, version, true)  // correct version
	_, nversion := doGetPermissions(t, rootCtx, mtAddr, "stuff", true)
	if nversion == version {
		boom(t, "version didn't change after SetPermissions: %s", nversion)
	}
	doSetPermissions(t, rootCtx, mtAddr, "stuff", perms, "", true) // no version

	// Bob should be able to create nodes under the mounttable root but not alice.
	doSetPermissions(t, aliceCtx, mtAddr, "onlybob", perms, "", false)
	doSetPermissions(t, bobCtx, mtAddr, "onlybob", perms, "", true)

	// Test that setting Permissions to permissions that don't include the the setter's
	// blessings in Admin, automatically add their Blessings to Admin to prevent
	// locking everyone out.
	perms, _ = doGetPermissions(t, bobCtx, mtAddr, "onlybob", true)
	noRootPerms := perms.Copy()
	noRootPerms.Clear("bob", "Admin")
	doSetPermissions(t, bobCtx, mtAddr, "onlybob", noRootPerms, "", true)
	// This should succeed, because "bob" should automatically be added to "Admin"
	// even though he cleared himself from "Admin".
	doSetPermissions(t, bobCtx, mtAddr, "onlybob", perms, "", true)
	// Test that adding a non-standard perms is normalized when retrieved.
	admin := perms["Admin"]
	admin.In = []security.BlessingPattern{"bob", "bob"}
	perms["Admin"] = admin
	doSetPermissions(t, bobCtx, mtAddr, "onlybob", perms, "", true)
	perms, _ = doGetPermissions(t, bobCtx, mtAddr, "onlybob", true)
	if got, want := perms["Admin"].In, []security.BlessingPattern{"bob"}; !reflect.DeepEqual(got, want) {
		boom(t, "got %v, want %v", got, want)
	}

	// Test generic unmount.
	vlog.Info("Test generic unmount.")
	doUnmount(t, rootCtx, mtAddr, "a/b", "", true)
	checkContents(t, rootCtx, naming.JoinAddressName(mtAddr, "a/b/falls"), "falls mainly on the plain", false)

	// Test specific unmount.
	vlog.Info("Test specific unmount.")
	doMount(t, rootCtx, mtAddr, "a/b", collectionName, true)
	doUnmount(t, rootCtx, mtAddr, "a/b", collectionName, true)
	checkContents(t, rootCtx, naming.JoinAddressName(mtAddr, "a/b/falls"), "falls mainly on the plain", false)

	// Try timing out a mount.
	vlog.Info("Try timing out a mount.")
	ft := NewFakeTimeClock()
	setServerListClock(ft)
	doMount(t, rootCtx, mtAddr, "stuffWithTTL", collectionName, true)
	checkContents(t, rootCtx, naming.JoinAddressName(mtAddr, "stuffWithTTL/the/rain"), "the rain", true)
	ft.advance(time.Duration(ttlSecs+4) * time.Second)
	checkContents(t, rootCtx, naming.JoinAddressName(mtAddr, "stuffWithTTL/the/rain"), "the rain", false)

	// Test unauthorized mount.
	vlog.Info("Test unauthorized mount.")
	doMount(t, bobCtx, mtAddr, "/a/b", collectionName, false)
	doMount(t, aliceCtx, mtAddr, "/a/b", collectionName, false)

	doUnmount(t, bobCtx, mtAddr, "x/y", collectionName, false)
}

func doGlobX(t *testing.T, ctx *context.T, ep, suffix, pattern string, joinServer bool) []string {
	name := naming.JoinAddressName(ep, suffix)
	client := v23.GetClient(ctx)
	call, err := client.StartCall(ctx, name, rpc.GlobMethod, []interface{}{pattern}, options.NoResolve{})
	if err != nil {
		boom(t, "Glob.StartCall %s %s: %s", name, pattern, err)
	}
	var reply []string
	for {
		var gr naming.GlobReply
		err := call.Recv(&gr)
		if err == io.EOF {
			break
		}
		if err != nil {
			boom(t, "Glob.StartCall %s: %s", name, pattern, err)
		}
		switch v := gr.(type) {
		case naming.GlobReplyEntry:
			if joinServer && len(v.Value.Servers) > 0 {
				reply = append(reply, naming.JoinAddressName(v.Value.Servers[0].Server, v.Value.Name))
			} else {
				reply = append(reply, v.Value.Name)
			}
		}
	}
	if err := call.Finish(); err != nil {
		boom(t, "Glob.Finish %s: %s", name, pattern, err)
	}
	return reply
}

func doGlob(t *testing.T, ctx *context.T, ep, suffix, pattern string) []string {
	return doGlobX(t, ctx, ep, suffix, pattern, false)
}

// checkMatch verified that the two slices contain the same string items, albeit
// not necessarily in the same order.  Item repetitions are allowed, but their
// numbers need to match as well.
func checkMatch(t *testing.T, want []string, got []string) {
	if len(want) == 0 && len(got) == 0 {
		return
	}
	w := sort.StringSlice(want)
	w.Sort()
	g := sort.StringSlice(got)
	g.Sort()
	if !reflect.DeepEqual(w, g) {
		boom(t, "Glob expected %v got %v", want, got)
	}
}

// checkExists makes sure a name exists (or not).
func checkExists(t *testing.T, ctx *context.T, ep, suffix string, shouldSucceed bool) {
	x := doGlobX(t, ctx, ep, "", suffix, false)
	if len(x) != 1 || x[0] != suffix {
		if shouldSucceed {
			boom(t, "Failed to find %s", suffix)
		}
		return
	}
	if !shouldSucceed {
		boom(t, "%s exists but shouldn't", suffix)
	}
}

func TestGlob(t *testing.T) {
	rootCtx, shutdown := test.InitForTest()
	defer shutdown()

	server, estr := newMT(t, "", "", rootCtx)
	defer server.Stop()

	// set up a mount space
	fakeServer := naming.JoinAddressName(estr, "quux")
	doMount(t, rootCtx, estr, "one/bright/day", fakeServer, true)
	doMount(t, rootCtx, estr, "in/the/middle", fakeServer, true)
	doMount(t, rootCtx, estr, "of/the/night", fakeServer, true)

	// Try various globs.
	tests := []struct {
		in       string
		expected []string
	}{
		{"*", []string{"one", "in", "of"}},
		{"...", []string{"", "one", "in", "of", "one/bright", "in/the", "of/the", "one/bright/day", "in/the/middle", "of/the/night"}},
		{"*/...", []string{"one", "in", "of", "one/bright", "in/the", "of/the", "one/bright/day", "in/the/middle", "of/the/night"}},
		{"one/...", []string{"one", "one/bright", "one/bright/day"}},
		{"of/the/night/two/dead/boys", []string{"of/the/night"}},
		{"*/the", []string{"in/the", "of/the"}},
		{"*/the/...", []string{"in/the", "of/the", "in/the/middle", "of/the/night"}},
		{"o*", []string{"one", "of"}},
		{"", []string{""}},
	}
	for _, test := range tests {
		out := doGlob(t, rootCtx, estr, "", test.in)
		checkMatch(t, test.expected, out)
	}

	// Test Glob on a name that is under a mounted server. The result should the
	// the address the mounted server with the extra suffix.
	{
		results := doGlobX(t, rootCtx, estr, "of/the/night/two/dead/boys/got/up/to/fight", "*", true)
		if len(results) != 1 {
			boom(t, "Unexpected number of results. Got %v, want 1", len(results))
		}
		_, suffix := naming.SplitAddressName(results[0])
		if expected := "quux/two/dead/boys/got/up/to/fight"; suffix != expected {
			boom(t, "Unexpected suffix. Got %v, want %v", suffix, expected)
		}
	}
}

func TestAccessListTemplate(t *testing.T) {
	rootCtx, aliceCtx, bobCtx, shutdown := initTest()
	defer shutdown()

	server, estr := newMT(t, "testdata/test.perms", "", rootCtx)
	defer server.Stop()
	fakeServer := naming.JoinAddressName(estr, "quux")

	// Noone should be able to mount on someone else's names.
	doMount(t, aliceCtx, estr, "users/ted", fakeServer, false)
	doMount(t, bobCtx, estr, "users/carol", fakeServer, false)
	doMount(t, rootCtx, estr, "users/george", fakeServer, false)

	// Anyone should be able to mount on their own names.
	doMount(t, aliceCtx, estr, "users/alice", fakeServer, true)
	doMount(t, bobCtx, estr, "users/bob", fakeServer, true)
	doMount(t, rootCtx, estr, "users/root", fakeServer, true)
}

func TestGlobAccessLists(t *testing.T) {
	rootCtx, aliceCtx, bobCtx, shutdown := initTest()
	defer shutdown()

	server, estr := newMT(t, "testdata/test.perms", "", rootCtx)
	defer server.Stop()

	// set up a mount space
	fakeServer := naming.JoinAddressName(estr, "quux")
	doMount(t, aliceCtx, estr, "one/bright/day", fakeServer, false) // Fails because alice can't mount there.
	doMount(t, bobCtx, estr, "one/bright/day", fakeServer, true)
	doMount(t, rootCtx, estr, "a/b/c", fakeServer, true)

	// Try various globs.
	tests := []struct {
		ctx      *context.T
		in       string
		expected []string
	}{
		{rootCtx, "*", []string{"one", "a", "stuff", "users"}},
		{aliceCtx, "*", []string{"one", "a", "users"}},
		{bobCtx, "*", []string{"one", "stuff", "users"}},
		// bob, alice, and root have different visibility to the space.
		{rootCtx, "*/...", []string{"one", "a", "one/bright", "a/b", "one/bright/day", "a/b/c", "stuff", "users"}},
		{aliceCtx, "*/...", []string{"one", "a", "one/bright", "a/b", "one/bright/day", "a/b/c", "users"}},
		{bobCtx, "*/...", []string{"one", "one/bright", "one/bright/day", "stuff", "users"}},
	}
	for _, test := range tests {
		out := doGlob(t, test.ctx, estr, "", test.in)
		checkMatch(t, test.expected, out)
	}
}

func TestCleanup(t *testing.T) {
	rootCtx, shutdown := test.InitForTest()
	defer shutdown()

	server, estr := newMT(t, "", "", rootCtx)
	defer server.Stop()

	// Set up one mount.
	fakeServer := naming.JoinAddressName(estr, "quux")
	doMount(t, rootCtx, estr, "one/bright/day", fakeServer, true)
	checkMatch(t, []string{"one", "one/bright", "one/bright/day"}, doGlob(t, rootCtx, estr, "", "*/..."))

	// After the unmount nothing should be left
	doUnmount(t, rootCtx, estr, "one/bright/day", "", true)
	checkMatch(t, nil, doGlob(t, rootCtx, estr, "", "*/..."))

	// Set up a mount, then set the AccessList.
	doMount(t, rootCtx, estr, "one/bright/day", fakeServer, true)
	checkMatch(t, []string{"one", "one/bright", "one/bright/day"}, doGlob(t, rootCtx, estr, "", "*/..."))
	perms := access.Permissions{"Read": access.AccessList{In: []security.BlessingPattern{security.AllPrincipals}}}
	doSetPermissions(t, rootCtx, estr, "one/bright", perms, "", true)

	// After the unmount we should still have everything above the AccessList.
	doUnmount(t, rootCtx, estr, "one/bright/day", "", true)
	checkMatch(t, []string{"one", "one/bright"}, doGlob(t, rootCtx, estr, "", "*/..."))
}

func TestDelete(t *testing.T) {
	rootCtx, aliceCtx, bobCtx, shutdown := initTest()
	defer shutdown()

	server, estr := newMT(t, "testdata/test.perms", "", rootCtx)
	defer server.Stop()

	// set up a mount space
	fakeServer := naming.JoinAddressName(estr, "quux")
	doMount(t, bobCtx, estr, "one/bright/day", fakeServer, true)
	doMount(t, rootCtx, estr, "a/b/c", fakeServer, true)

	// It shouldn't be possible to delete anything with children unless explicitly requested.
	doDeleteNode(t, rootCtx, estr, "a/b", false)
	checkExists(t, rootCtx, estr, "a/b", true)
	doDeleteSubtree(t, rootCtx, estr, "a/b", true)
	checkExists(t, rootCtx, estr, "a/b", false)

	// Alice shouldn't be able to delete what bob created but bob and root should.
	doDeleteNode(t, aliceCtx, estr, "one/bright/day", false)
	checkExists(t, rootCtx, estr, "one/bright/day", true)
	doDeleteNode(t, rootCtx, estr, "one/bright/day", true)
	checkExists(t, rootCtx, estr, "one/bright/day", false)
	doDeleteNode(t, bobCtx, estr, "one/bright", true)
	checkExists(t, rootCtx, estr, "one/bright", false)
}

func TestServerFormat(t *testing.T) {
	rootCtx, shutdown := test.InitForTest()
	defer shutdown()

	server, estr := newMT(t, "", "", rootCtx)
	defer server.Stop()

	doMount(t, rootCtx, estr, "endpoint", naming.JoinAddressName(estr, "life/on/the/mississippi"), true)
	doMount(t, rootCtx, estr, "hostport", "/atrampabroad:8000", true)
	doMount(t, rootCtx, estr, "invalid/not/rooted", "atrampabroad:8000", false)
	doMount(t, rootCtx, estr, "invalid/no/port", "/atrampabroad", false)
	doMount(t, rootCtx, estr, "invalid/endpoint", "/@following the equator:8000@@@", false)
}

func TestExpiry(t *testing.T) {
	rootCtx, shutdown := test.InitForTest()
	defer shutdown()

	server, estr := newMT(t, "", "", rootCtx)
	defer server.Stop()
	collection, collectionAddr := newCollection(t, rootCtx)
	defer collection.Stop()

	collectionName := naming.JoinAddressName(collectionAddr, "collection")

	ft := NewFakeTimeClock()
	setServerListClock(ft)
	doMount(t, rootCtx, estr, "a1/b1", collectionName, true)
	doMount(t, rootCtx, estr, "a1/b2", collectionName, true)
	doMount(t, rootCtx, estr, "a2/b1", collectionName, true)
	doMount(t, rootCtx, estr, "a2/b2/c", collectionName, true)

	checkMatch(t, []string{"a1/b1", "a2/b1"}, doGlob(t, rootCtx, estr, "", "*/b1/..."))
	ft.advance(time.Duration(ttlSecs/2) * time.Second)
	checkMatch(t, []string{"a1/b1", "a2/b1"}, doGlob(t, rootCtx, estr, "", "*/b1/..."))
	checkMatch(t, []string{"c"}, doGlob(t, rootCtx, estr, "a2/b2", "*"))
	// Refresh only a1/b1.  All the other mounts will expire upon the next
	// ft advance.
	doMount(t, rootCtx, estr, "a1/b1", collectionName, true)
	ft.advance(time.Duration(ttlSecs/2+4) * time.Second)
	checkMatch(t, []string{"a1", "a1/b1"}, doGlob(t, rootCtx, estr, "", "*/..."))
	checkMatch(t, []string{"a1/b1"}, doGlob(t, rootCtx, estr, "", "*/b1/..."))
}

func TestBadAccessLists(t *testing.T) {
	_, err := NewMountTableDispatcher("testdata/invalid.perms", "", "mounttable")
	if err == nil {
		boom(t, "Expected json parse error in permissions file")
	}
	_, err = NewMountTableDispatcher("testdata/doesntexist.perms", "", "mounttable")
	if err != nil {
		boom(t, "Missing permissions file should not cause an error")
	}
}

func getCounter(t *testing.T, ctx *context.T, name string) int64 {
	st := stats.StatsClient(name)
	v, err := st.Value(ctx)
	if err != nil {
		t.Fatalf("Failed to get %q: %v", name, err)
		return -1
	}
	var value int64
	if err := vdl.Convert(&value, v); err != nil {
		t.Fatalf("Unexpected value type for %q: %v", name, err)
	}
	return value
}

func nodeCount(t *testing.T, ctx *context.T, addr string) int64 {
	name := naming.JoinAddressName(addr, "__debug/stats/mounttable/num-nodes")
	return getCounter(t, ctx, name)
}

func serverCount(t *testing.T, ctx *context.T, addr string) int64 {
	name := naming.JoinAddressName(addr, "__debug/stats/mounttable/num-mounted-servers")
	return getCounter(t, ctx, name)
}

func TestStatsCounters(t *testing.T) {
	rootCtx, shutdown := test.InitForTest()
	defer shutdown()

	ft := NewFakeTimeClock()
	setServerListClock(ft)

	server, estr := newMT(t, "", "", rootCtx)
	defer server.Stop()

	// Test flat tree
	for i := 1; i <= 10; i++ {
		name := fmt.Sprintf("node%d", i)
		addr := naming.JoinAddressName(estr, name)
		doMount(t, rootCtx, estr, name, addr, true)
		if expected, got := int64(i+1), nodeCount(t, rootCtx, estr); got != expected {
			t.Errorf("Unexpected number of nodes. Got %d, expected %d", got, expected)
		}
		if expected, got := int64(i), serverCount(t, rootCtx, estr); got != expected {
			t.Errorf("Unexpected number of servers. Got %d, expected %d", got, expected)
		}
	}
	for i := 1; i <= 10; i++ {
		name := fmt.Sprintf("node%d", i)
		if i%2 == 0 {
			doUnmount(t, rootCtx, estr, name, "", true)
		} else {
			doDeleteSubtree(t, rootCtx, estr, name, true)
		}
		if expected, got := int64(11-i), nodeCount(t, rootCtx, estr); got != expected {
			t.Errorf("Unexpected number of nodes. Got %d, expected %d", got, expected)
		}
		if expected, got := int64(10-i), serverCount(t, rootCtx, estr); got != expected {
			t.Errorf("Unexpected number of server. Got %d, expected %d", got, expected)
		}
	}

	// Test deep tree
	doMount(t, rootCtx, estr, "1/2/3/4/5/6/7/8/9a/10", naming.JoinAddressName(estr, ""), true)
	doMount(t, rootCtx, estr, "1/2/3/4/5/6/7/8/9b/11", naming.JoinAddressName(estr, ""), true)
	if expected, got := int64(13), nodeCount(t, rootCtx, estr); got != expected {
		t.Errorf("Unexpected number of nodes. Got %d, expected %d", got, expected)
	}
	if expected, got := int64(2), serverCount(t, rootCtx, estr); got != expected {
		t.Errorf("Unexpected number of servers. Got %d, expected %d", got, expected)
	}
	doDeleteSubtree(t, rootCtx, estr, "1/2/3/4/5", true)
	if expected, got := int64(5), nodeCount(t, rootCtx, estr); got != expected {
		t.Errorf("Unexpected number of nodes. Got %d, expected %d", got, expected)
	}
	if expected, got := int64(0), serverCount(t, rootCtx, estr); got != expected {
		t.Errorf("Unexpected number of servers. Got %d, expected %d", got, expected)
	}
	doDeleteSubtree(t, rootCtx, estr, "1", true)
	if expected, got := int64(1), nodeCount(t, rootCtx, estr); got != expected {
		t.Errorf("Unexpected number of nodes. Got %d, expected %d", got, expected)
	}

	// Test multiple servers per node
	for i := 1; i <= 5; i++ {
		server := naming.JoinAddressName(estr, fmt.Sprintf("addr%d", i))
		doMount(t, rootCtx, estr, "node1", server, true)
		doMount(t, rootCtx, estr, "node2", server, true)
		if expected, got := int64(3), nodeCount(t, rootCtx, estr); got != expected {
			t.Errorf("Unexpected number of nodes. Got %d, expected %d", got, expected)
		}
		if expected, got := int64(2*i), serverCount(t, rootCtx, estr); got != expected {
			t.Errorf("Unexpected number of servers. Got %d, expected %d", got, expected)
		}
	}
	doUnmount(t, rootCtx, estr, "node1", "", true)
	if expected, got := int64(2), nodeCount(t, rootCtx, estr); got != expected {
		t.Errorf("Unexpected number of nodes. Got %d, expected %d", got, expected)
	}
	if expected, got := int64(5), serverCount(t, rootCtx, estr); got != expected {
		t.Errorf("Unexpected number of servers. Got %d, expected %d", got, expected)
	}
	for i := 1; i <= 5; i++ {
		server := naming.JoinAddressName(estr, fmt.Sprintf("addr%d", i))
		doUnmount(t, rootCtx, estr, "node2", server, true)
		expectedNodes := int64(2)
		if i == 5 {
			expectedNodes = 1
		}
		if expected, got := expectedNodes, nodeCount(t, rootCtx, estr); got != expected {
			t.Errorf("Unexpected number of nodes. Got %d, expected %d", got, expected)
		}
		if expected, got := int64(5-i), serverCount(t, rootCtx, estr); got != expected {
			t.Errorf("Unexpected number of servers. Got %d, expected %d", got, expected)
		}
	}

	// Mount on an existing intermediate node.
	doMount(t, rootCtx, estr, "1/2/3/4/5/6/7/8/9a/10", naming.JoinAddressName(estr, ""), true)
	doMount(t, rootCtx, estr, "1/2/3/4/5", naming.JoinAddressName(estr, ""), true)
	if expected, got := int64(6), nodeCount(t, rootCtx, estr); got != expected {
		t.Errorf("Unexpected number of nodes. Got %d, expected %d", got, expected)
	}
	if expected, got := int64(1), serverCount(t, rootCtx, estr); got != expected {
		t.Errorf("Unexpected number of servers. Got %d, expected %d", got, expected)
	}

	// Test expired mounts
	// "1/2/3/4/5" is still mounted from earlier.
	ft.advance(time.Duration(ttlSecs+4) * time.Second)
	if _, err := resolve(rootCtx, naming.JoinAddressName(estr, "1/2/3/4/5")); err == nil {
		t.Errorf("Expected failure. Got success")
	}
	if expected, got := int64(0), serverCount(t, rootCtx, estr); got != expected {
		t.Errorf("Unexpected number of servers. Got %d, expected %d", got, expected)
	}
}

func initTest() (rootCtx *context.T, aliceCtx *context.T, bobCtx *context.T, shutdown v23.Shutdown) {
	test.Init()
	ctx, shutdown := test.InitForTest()
	var err error
	if rootCtx, err = v23.WithPrincipal(ctx, testutil.NewPrincipal("root")); err != nil {
		panic("failed to set root principal")
	}
	if aliceCtx, err = v23.WithPrincipal(ctx, testutil.NewPrincipal("alice")); err != nil {
		panic("failed to set alice principal")
	}
	if bobCtx, err = v23.WithPrincipal(ctx, testutil.NewPrincipal("bob")); err != nil {
		panic("failed to set bob principal")
	}
	for _, r := range []*context.T{rootCtx, aliceCtx, bobCtx} {
		// A hack to set the namespace roots to a value that won't work.
		v23.GetNamespace(r).SetRoots()
		// And have all principals recognize each others blessings.
		p1 := v23.GetPrincipal(r)
		for _, other := range []*context.T{rootCtx, aliceCtx, bobCtx} {
			// testutil.NewPrincipal has already setup each
			// principal to use the same blessing for both server
			// and client activities.
			if err := p1.AddToRoots(v23.GetPrincipal(other).BlessingStore().Default()); err != nil {
				panic(err)
			}
		}
	}
	return rootCtx, aliceCtx, bobCtx, shutdown
}