// Copyright 2017 Pilosa Corp.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package pilosa_test

import (
	"bytes"
	"context"
	"os"
	"path/filepath"
	"reflect"
	"strings"
	"testing"

	"github.com/pilosa/pilosa"
	"github.com/pilosa/pilosa/test"
)

func TestHolder_Open(t *testing.T) {
	t.Run("ErrIndexName", func(t *testing.T) {
		h := test.MustOpenHolder()

		bufLogger := test.NewBufferLogger()
		h.Holder.Logger = bufLogger

		defer h.Close()

		if err := os.Mkdir(h.IndexPath("!"), 0777); err != nil {
			t.Fatal(err)
		} else if err := h.Holder.Close(); err != nil {
			t.Fatal(err)
		}
		if err := h.Reopen(); err != nil {
			t.Fatal(err)
		}

		if bufbytes, err := bufLogger.ReadAll(); err != nil {
			t.Fatal(err)
		} else if !bytes.Contains(bufbytes, []byte("ERROR opening index: !")) {
			t.Fatalf("expected log error:\n%s", bufbytes)
		}
	})

	t.Run("ErrIndexPermission", func(t *testing.T) {
		if os.Geteuid() == 0 {
			t.Skip("Skipping permissions test since user is root.")
		}
		h := test.MustOpenHolder()
		defer h.Close()

		if _, err := h.CreateIndex("test", pilosa.IndexOptions{}); err != nil {
			t.Fatal(err)
		} else if err := h.Holder.Close(); err != nil {
			t.Fatal(err)
		} else if err := os.Chmod(h.IndexPath("test"), 0000); err != nil {
			t.Fatal(err)
		}
		defer os.Chmod(h.IndexPath("test"), 0777)

		if err := h.Reopen(); err == nil || !strings.Contains(err.Error(), "permission denied") {
			t.Fatalf("unexpected error: %s", err)
		}
	})
	t.Run("ErrIndexAttrStoreCorrupt", func(t *testing.T) {
		h := test.MustOpenHolder()
		defer h.Close()

		if _, err := h.CreateIndex("test", pilosa.IndexOptions{}); err != nil {
			t.Fatal(err)
		} else if err := h.Holder.Close(); err != nil {
			t.Fatal(err)
		} else if err := os.Truncate(filepath.Join(h.IndexPath("test"), ".data"), 2); err != nil {
			t.Fatal(err)
		}

		if err := h.Reopen(); err == nil || !strings.Contains(err.Error(), "open index: name=test, err=opening attrstore: opening storage: invalid database") {
			t.Fatalf("unexpected error: %s", err)
		}
	})

	t.Run("ErrFieldPermission", func(t *testing.T) {
		if os.Geteuid() == 0 {
			t.Skip("Skipping permissions test since user is root.")
		}
		h := test.MustOpenHolder()
		defer h.Close()

		if idx, err := h.CreateIndex("foo", pilosa.IndexOptions{}); err != nil {
			t.Fatal(err)
		} else if _, err := idx.CreateField("bar", pilosa.OptFieldTypeDefault()); err != nil {
			t.Fatal(err)
		} else if err := h.Holder.Close(); err != nil {
			t.Fatal(err)
		} else if err := os.Chmod(filepath.Join(h.Path, "foo", "bar"), 0000); err != nil {
			t.Fatal(err)
		}
		defer os.Chmod(filepath.Join(h.Path, "foo", "bar"), 0777)

		if err := h.Reopen(); err == nil || !strings.Contains(err.Error(), "permission denied") {
			t.Fatalf("unexpected error: %s", err)
		}
	})
	t.Run("ErrFieldOptionsCorrupt", func(t *testing.T) {
		h := test.MustOpenHolder()
		defer h.Close()

		if idx, err := h.CreateIndex("foo", pilosa.IndexOptions{}); err != nil {
			t.Fatal(err)
		} else if _, err := idx.CreateField("bar", pilosa.OptFieldTypeDefault()); err != nil {
			t.Fatal(err)
		} else if err := h.Holder.Close(); err != nil {
			t.Fatal(err)
		} else if err := os.Truncate(filepath.Join(h.Path, "foo", "bar", ".meta"), 2); err != nil {
			t.Fatal(err)
		}

		if err := h.Reopen(); err == nil || !strings.Contains(err.Error(), "open index: name=foo, err=opening fields: open field: name=bar, err=loading meta: unmarshaling: unexpected EOF") {
			t.Fatalf("unexpected error: %s", err)
		}
	})
	t.Run("ErrFieldAttrStoreCorrupt", func(t *testing.T) {
		h := test.MustOpenHolder()
		defer h.Close()

		if idx, err := h.CreateIndex("foo", pilosa.IndexOptions{}); err != nil {
			t.Fatal(err)
		} else if _, err := idx.CreateField("bar", pilosa.OptFieldTypeDefault()); err != nil {
			t.Fatal(err)
		} else if err := h.Holder.Close(); err != nil {
			t.Fatal(err)
		} else if err := os.Truncate(filepath.Join(h.Path, "foo", "bar", ".data"), 2); err != nil {
			t.Fatal(err)
		}

		if err := h.Reopen(); err == nil || !strings.Contains(err.Error(), "open index: name=foo, err=opening fields: open field: name=bar, err=opening attrstore: opening storage: invalid database") {
			t.Fatalf("unexpected error: %s", err)
		}
	})

	t.Run("ErrFragmentStoragePermission", func(t *testing.T) {
		if os.Geteuid() == 0 {
			t.Skip("Skipping permissions test since user is root.")
		}
		h := test.MustOpenHolder()
		defer h.Close()

		if idx, err := h.CreateIndex("foo", pilosa.IndexOptions{}); err != nil {
			t.Fatal(err)
		} else if field, err := idx.CreateField("bar", pilosa.OptFieldTypeDefault()); err != nil {
			t.Fatal(err)
		} else if _, err := field.SetBit(0, 0, nil); err != nil {
			t.Fatal(err)
		} else if err := h.Holder.Close(); err != nil {
			t.Fatal(err)
		} else if err := os.Chmod(filepath.Join(h.Path, "foo", "bar", "views", "standard", "fragments", "0"), 0000); err != nil {
			t.Fatal(err)
		}
		defer os.Chmod(filepath.Join(h.Path, "foo", "bar", "views", "standard", "fragments", "0"), 0666)

		if err := h.Reopen(); err == nil || !strings.Contains(err.Error(), "permission denied") {
			t.Fatalf("unexpected error: %s", err)
		}
	})
	t.Run("ErrFragmentStorageCorrupt", func(t *testing.T) {
		h := test.MustOpenHolder()
		defer h.Close()

		if idx, err := h.CreateIndex("foo", pilosa.IndexOptions{}); err != nil {
			t.Fatal(err)
		} else if field, err := idx.CreateField("bar", pilosa.OptFieldTypeDefault()); err != nil {
			t.Fatal(err)
		} else if _, err := field.SetBit(0, 0, nil); err != nil {
			t.Fatal(err)
		} else if err := h.Holder.Close(); err != nil {
			t.Fatal(err)
		} else if err := os.Truncate(filepath.Join(h.Path, "foo", "bar", "views", "standard", "fragments", "0"), 2); err != nil {
			t.Fatal(err)
		}

		if err := h.Reopen(); err == nil || !strings.Contains(err.Error(), "open fragment: shard=0, err=opening storage: unmarshal storage") {
			t.Fatalf("unexpected error: %s", err)
		}
	})

}

func TestHolder_HasData(t *testing.T) {
	t.Run("IndexDirectory", func(t *testing.T) {
		h := test.MustOpenHolder()
		defer h.Close()

		if ok, err := h.HasData(); ok || err != nil {
			t.Fatal("expected HasData to return false, no err, but", ok, err)
		}

		if _, err := h.CreateIndex("test", pilosa.IndexOptions{}); err != nil {
			t.Fatal(err)
		}

		if ok, err := h.HasData(); !ok || err != nil {
			t.Fatal("expected HasData to return true, but ", ok, err)
		}
	})

	t.Run("Peek", func(t *testing.T) {
		h := test.NewHolder()

		if ok, err := h.HasData(); ok || err != nil {
			t.Fatal("expected HasData to return false, no err, but", ok, err)
		}

		// Create an index directory to indicate data exists.
		if err := os.Mkdir(h.IndexPath("test"), 0777); err != nil {
			t.Fatal(err)
		}

		if ok, err := h.HasData(); !ok || err != nil {
			t.Fatal("expected HasData to return true, no err, but", ok, err)
		}
	})

	t.Run("Peek at missing directory", func(t *testing.T) {
		h := test.NewHolder()

		// Ensure that hasData is false when dir doesn't exist.
		h.Path = "bad-path"

		if ok, err := h.HasData(); ok || err != nil {
			t.Fatal("expected HasData to return false, no err, but", ok, err)
		}
	})
}

// Ensure holder can delete an index and its underlying files.
func TestHolder_DeleteIndex(t *testing.T) {
	hldr := test.MustOpenHolder()
	defer hldr.Close()

	// Write bits to separate indexes.
	hldr.SetBit("i0", "f", 100, 200)
	hldr.SetBit("i1", "f", 100, 200)

	// Ensure i0 exists.
	if _, err := os.Stat(hldr.IndexPath("i0")); err != nil {
		t.Fatal(err)
	}

	// Delete i0.
	if err := hldr.DeleteIndex("i0"); err != nil {
		t.Fatal(err)
	}

	// Ensure i0 files are removed & i1 still exists.
	if _, err := os.Stat(hldr.IndexPath("i0")); !os.IsNotExist(err) {
		t.Fatal("expected i0 file deletion")
	} else if _, err := os.Stat(hldr.IndexPath("i1")); err != nil {
		t.Fatal("expected i1 files to still exist", err)
	}
}

// Ensure holder can sync with a remote holder.
func TestHolderSyncer_SyncHolder(t *testing.T) {
	c := test.MustNewCluster(t, 2)
	c[0].Config.Cluster.ReplicaN = 2
	c[0].Config.AntiEntropy.Interval = 0
	c[1].Config.Cluster.ReplicaN = 2
	c[1].Config.AntiEntropy.Interval = 0
	err := c.Start()
	if err != nil {
		t.Fatalf("starting cluster: %v", err)
	}
	defer c.Close()

	_, err = c[0].API.CreateIndex(context.Background(), "i", pilosa.IndexOptions{})
	if err != nil {
		t.Fatalf("creating index i: %v", err)
	}
	_, err = c[0].API.CreateIndex(context.Background(), "y", pilosa.IndexOptions{})
	if err != nil {
		t.Fatalf("creating index y: %v", err)
	}
	_, err = c[0].API.CreateField(context.Background(), "i", "f", pilosa.OptFieldTypeSet(pilosa.DefaultCacheType, pilosa.DefaultCacheSize))
	if err != nil {
		t.Fatalf("creating field f: %v", err)
	}
	_, err = c[0].API.CreateField(context.Background(), "i", "f0", pilosa.OptFieldTypeSet(pilosa.DefaultCacheType, pilosa.DefaultCacheSize))
	if err != nil {
		t.Fatalf("creating field f0: %v", err)
	}
	_, err = c[0].API.CreateField(context.Background(), "y", "z", pilosa.OptFieldTypeSet(pilosa.DefaultCacheType, pilosa.DefaultCacheSize))
	if err != nil {
		t.Fatalf("creating field z in y: %v", err)
	}

	hldr0 := &test.Holder{Holder: c[0].Server.Holder()}
	hldr1 := &test.Holder{Holder: c[1].Server.Holder()}

	// Set data on the local holder.
	hldr0.SetBit("i", "f", 0, 10)
	hldr0.SetBit("i", "f", 2, 20)
	hldr0.SetBit("i", "f", 120, 10)
	hldr0.SetBit("i", "f", 200, 4)

	hldr0.SetBit("i", "f0", 9, ShardWidth+5)

	// Set a bit to create the fragment.
	hldr0.SetBit("y", "z", 0, 0)

	// Set data on the remote holder.
	hldr1.SetBit("i", "f", 0, 4000)
	hldr1.SetBit("i", "f", 3, 10)
	hldr1.SetBit("i", "f", 120, 10)

	hldr1.SetBit("y", "z", 10, (3*ShardWidth)+4)
	hldr1.SetBit("y", "z", 10, (3*ShardWidth)+5)
	hldr1.SetBit("y", "z", 10, (3*ShardWidth)+7)

	err = c[0].Server.SyncData()
	if err != nil {
		t.Fatalf("syncing node 0: %v", err)
	}
	err = c[1].Server.SyncData()
	if err != nil {
		t.Fatalf("syncing node 1: %v", err)
	}

	// Verify data is the same on both nodes.
	for i, hldr := range []*test.Holder{hldr0, hldr1} {
		if a := hldr.Row("i", "f", 0).Columns(); !reflect.DeepEqual(a, []uint64{10, 4000}) {
			t.Errorf("unexpected columns(%d/0): %+v", i, a)
		}
		if a := hldr.Row("i", "f", 2).Columns(); !reflect.DeepEqual(a, []uint64{20}) {
			t.Errorf("unexpected columns(%d/2): %+v", i, a)
		}
		if a := hldr.Row("i", "f", 3).Columns(); !reflect.DeepEqual(a, []uint64{10}) {
			t.Errorf("unexpected columns(%d/3): %+v", i, a)
		}
		if a := hldr.Row("i", "f", 120).Columns(); !reflect.DeepEqual(a, []uint64{10}) {
			t.Errorf("unexpected columns(%d/120): %+v", i, a)
		}
		if a := hldr.Row("i", "f", 200).Columns(); !reflect.DeepEqual(a, []uint64{4}) {
			t.Errorf("unexpected columns(%d/200): %+v", i, a)
		}

		if a := hldr.Row("i", "f0", 9).Columns(); !reflect.DeepEqual(a, []uint64{ShardWidth + 5}) {
			t.Errorf("unexpected columns(%d/d/f0): %+v", i, a)
		}

		if a := hldr.Row("y", "z", 10).Columns(); !reflect.DeepEqual(a, []uint64{(3 * ShardWidth) + 4, (3 * ShardWidth) + 5, (3 * ShardWidth) + 7}) {
			t.Errorf("unexpected columns(%d/y/z): %+v", i, a)
		}
	}
}