package cacher

import (
	"context"
	"os"
	"testing"

	"github.com/stretchr/testify/mock"
	"github.com/stretchr/testify/require"
	"go.skia.org/infra/go/cas/mocks"
	"go.skia.org/infra/go/cas/rbe"
	"go.skia.org/infra/go/deepequal/assertdeep"
	depot_tools_testutils "go.skia.org/infra/go/depot_tools/testutils"
	"go.skia.org/infra/go/git/repograph"
	git_testutils "go.skia.org/infra/go/git/testutils"
	"go.skia.org/infra/go/testutils"
	"go.skia.org/infra/task_scheduler/go/specs"
	"go.skia.org/infra/task_scheduler/go/syncer"
	"go.skia.org/infra/task_scheduler/go/task_cfg_cache"
	tcc_testutils "go.skia.org/infra/task_scheduler/go/task_cfg_cache/testutils"
	"go.skia.org/infra/task_scheduler/go/types"
)

func setup(t *testing.T) (context.Context, *CacherImpl, task_cfg_cache.TaskCfgCache, *mocks.CAS, types.RepoState, *git_testutils.GitBuilder, func()) {
	ctx, gb, rev, _ := tcc_testutils.SetupTestRepo(t)
	ctx, cancel := context.WithCancel(ctx)

	rs := types.RepoState{
		Repo:     gb.RepoUrl(),
		Revision: rev,
	}

	wd, err := os.MkdirTemp("", "")
	require.NoError(t, err)
	repos, err := repograph.NewLocalMap(ctx, []string{gb.RepoUrl()}, wd)
	require.NoError(t, err)
	depotTools := depot_tools_testutils.GetDepotTools(t, ctx)
	s := syncer.New(ctx, repos, depotTools, wd, 1)
	btProject, btInstance, btCleanup := tcc_testutils.SetupBigTable(t)
	tcc, err := task_cfg_cache.NewTaskCfgCache(ctx, repos, btProject, btInstance, nil)
	require.NoError(t, err)
	cas := &mocks.CAS{}
	c := New(s, tcc, cas)
	return ctx, c, tcc, cas, rs, gb, func() {
		testutils.RemoveAll(t, wd)
		gb.Cleanup()
		btCleanup()
		cancel()
	}
}

func TestGetOrCacheRepoState_AlreadySet(t *testing.T) {
	ctx, c, tcc, _, _, _, cleanup := setup(t)
	defer cleanup()

	// This RepoState can't be synced.
	rs := types.RepoState{
		Repo:     "fake/repo.git",
		Revision: "abc123",
	}

	// Verify that GetOrCacheRepoState returns an error when it needs to sync,
	// to ensure that we can trust the below result.
	_, err := c.GetOrCacheRepoState(ctx, rs)
	require.Error(t, err)

	// Insert entries into the task config cache.
	expect := &specs.TasksCfg{
		Tasks: map[string]*specs.TaskSpec{
			"task": {},
		},
		Jobs: map[string]*specs.JobSpec{
			"job": {},
		},
	}
	require.NoError(t, tcc.Set(ctx, rs, expect, nil))

	// Retrieve the cached value. Ensure that there is no error, which implies
	// that we didn't attempt to sync.
	actual, err := c.GetOrCacheRepoState(ctx, rs)
	require.NoError(t, err)
	assertdeep.Equal(t, expect, actual)
}

func TestGetOrCacheRepoState_Unset_RBE(t *testing.T) {
	ctx, c, tcc, cas, rs, gb, cleanup := setup(t)
	defer cleanup()

	// Switch the config to use RBE-CAS.
	tasksCfg := tcc_testutils.TasksCfg2.Copy()
	tasksCfg.CasSpecs = map[string]*specs.CasSpec{
		"my-cas": {
			Root:     ".",
			Paths:    []string{"somefile.txt"},
			Excludes: []string{rbe.ExcludeGitDir},
		},
	}
	for _, task := range tasksCfg.Tasks {
		task.CasSpec = "my-cas"
	}
	gb.Add(ctx, "infra/bots/tasks.json", testutils.MarshalIndentJSON(t, tasksCfg))
	commit := gb.CommitMsg(ctx, "use rbe-cas")
	rs.Revision = commit

	// Verify that the cache entry doesn't exist yet.
	cached, cachedErr, err := tcc.Get(ctx, rs)
	require.EqualError(t, task_cfg_cache.ErrNoSuchEntry, err.Error())
	require.Nil(t, cachedErr)
	require.Nil(t, cached)

	// Run GetOrCacheRepoState to populate the cache.
	cas.On("Upload", testutils.AnyContext, mock.AnythingOfType("string"), []string{"somefile.txt"}, []string{rbe.ExcludeGitDir}).Return("fake-digest", nil)
	_, err = c.GetOrCacheRepoState(ctx, rs)
	require.NoError(t, err)

	// Verify that the cache entry now exists.
	cached, cachedErr, err = tcc.Get(ctx, rs)
	require.NoError(t, err)
	require.Nil(t, cachedErr)
	require.NotNil(t, cached)
	require.Equal(t, "fake-digest", cached.CasSpecs["my-cas"].Digest)
}