// Copyright 2022 TiKV Project Authors.
//
// 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 keyspace

import (
	"context"
	"encoding/hex"
	"math"
	"testing"
	"time"

	"github.com/stretchr/testify/require"
	"github.com/tikv/pd/pkg/codec"
	keyspaceconstant "github.com/tikv/pd/pkg/keyspace/constant"
	"github.com/tikv/pd/pkg/mcs/utils/constant"
	"github.com/tikv/pd/pkg/schedule/labeler"
	"github.com/tikv/pd/pkg/storage/endpoint"
	"github.com/tikv/pd/pkg/storage/kv"
)

func TestValidateID(t *testing.T) {
	re := require.New(t)
	testCases := []struct {
		id     uint32
		hasErr bool
	}{
		{constant.DefaultKeyspaceID, true}, // Reserved id should result in error.
		{100, false},
		{keyspaceconstant.MaxValidKeyspaceID - 1, false},
		{keyspaceconstant.MaxValidKeyspaceID, false},
		{keyspaceconstant.MaxValidKeyspaceID + 1, true},
		{math.MaxUint32, true},
	}
	for _, testCase := range testCases {
		re.Equal(testCase.hasErr, validateID(testCase.id) != nil)
	}
}

func TestMakeRegionBound(t *testing.T) {
	re := require.New(t)
	encodeKey := func(key []byte) []byte {
		return []byte(codec.EncodeBytes(key))
	}

	regionBound := MakeRegionBound(0x010203)
	re.Equal(encodeKey([]byte{'r', 0x01, 0x02, 0x03}), regionBound.RawLeftBound)
	re.Equal(encodeKey([]byte{'r', 0x01, 0x02, 0x04}), regionBound.RawRightBound)
	re.Equal(encodeKey([]byte{'x', 0x01, 0x02, 0x03}), regionBound.TxnLeftBound)
	re.Equal(encodeKey([]byte{'x', 0x01, 0x02, 0x04}), regionBound.TxnRightBound)

	carryRegionBound := MakeRegionBound(0x0102ff)
	re.Equal(encodeKey([]byte{'r', 0x01, 0x03, 0x00}), carryRegionBound.RawRightBound)
	re.Equal(encodeKey([]byte{'x', 0x01, 0x03, 0x00}), carryRegionBound.TxnRightBound)

	maxRegionBound := MakeRegionBound(keyspaceconstant.MaxValidKeyspaceID)
	re.Equal(encodeKey([]byte{'r', 0xff, 0xff, 0xff}), maxRegionBound.RawLeftBound)
	re.Equal(encodeKey([]byte{'s', 0x00, 0x00, 0x00}), maxRegionBound.RawRightBound)
	re.Equal(encodeKey([]byte{'x', 0xff, 0xff, 0xff}), maxRegionBound.TxnLeftBound)
	re.Equal(encodeKey([]byte{'y', 0x00, 0x00, 0x00}), maxRegionBound.TxnRightBound)
}

func TestMakeKeyspacePrefix(t *testing.T) {
	re := require.New(t)

	testCases := []struct {
		name       string
		mode       byte
		id         uint32
		wantPrefix []byte
	}{
		{
			name:       "raw",
			mode:       RawKeyspaceModePrefix,
			id:         0x010203,
			wantPrefix: []byte{'r', 0x01, 0x02, 0x03},
		},
		{
			name:       "txn",
			mode:       TxnKeyspaceModePrefix,
			id:         keyspaceconstant.MaxValidKeyspaceID,
			wantPrefix: []byte{'x', 0xff, 0xff, 0xff},
		},
	}

	for _, testCase := range testCases {
		t.Run(testCase.name, func(_ *testing.T) {
			re.Equal(testCase.wantPrefix, MakeKeyspacePrefix(testCase.mode, testCase.id))
		})
	}
}

func TestMaxKeyspaceLabelRuleSplitKeys(t *testing.T) {
	re := require.New(t)
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()
	regionLabeler, err := labeler.NewRegionLabeler(ctx, endpoint.NewStorageEndpoint(kv.NewMemoryKV(), nil), time.Hour)
	re.NoError(err)

	re.NoError(regionLabeler.SetLabelRule(makeLabelRule(keyspaceconstant.MaxValidKeyspaceID, false)))
	encodeKey := func(key []byte) []byte {
		return []byte(codec.EncodeBytes(key))
	}
	re.Equal(
		[][]byte{
			encodeKey([]byte{'r', 0xff, 0xff, 0xff}),
			encodeKey([]byte{'s', 0x00, 0x00, 0x00}),
			encodeKey([]byte{'x', 0xff, 0xff, 0xff}),
			encodeKey([]byte{'y', 0x00, 0x00, 0x00}),
		},
		regionLabeler.GetSplitKeys(nil, nil),
	)
}

func TestValidateName(t *testing.T) {
	re := require.New(t)
	testCases := []struct {
		name   string
		hasErr bool
	}{
		{constant.DefaultKeyspaceName, true}, // Reserved name should result in error.
		{"keyspaceName1", false},
		{"keyspace_name_1", false},
		{"10", false},
		{"", true},
		{"keyspace/", true},
		{"keyspace:1", true},
		{"many many spaces", true},
		{"keyspace?limit=1", true},
		{"keyspace%1", true},
	}
	for _, testCase := range testCases {
		re.Equal(testCase.hasErr, validateName(testCase.name) != nil)
	}
}

func TestMakeLabelRule(t *testing.T) {
	re := require.New(t)
	testCases := []struct {
		id                uint32
		skipRaw           bool
		expectedLabelRule *labeler.LabelRule
	}{
		{
			id:      0,
			skipRaw: false,
			expectedLabelRule: &labeler.LabelRule{
				ID:    "keyspaces/0",
				Index: 0,
				Labels: []labeler.RegionLabel{
					{
						Key:   "id",
						Value: "0",
					},
				},
				RuleType: "key-range",
				Data: []any{
					map[string]any{
						"start_key": hex.EncodeToString(codec.EncodeBytes([]byte{'r', 0, 0, 0})),
						"end_key":   hex.EncodeToString(codec.EncodeBytes([]byte{'r', 0, 0, 1})),
					},
					map[string]any{
						"start_key": hex.EncodeToString(codec.EncodeBytes([]byte{'x', 0, 0, 0})),
						"end_key":   hex.EncodeToString(codec.EncodeBytes([]byte{'x', 0, 0, 1})),
					},
				},
			},
		},
		{
			id:      4242,
			skipRaw: false,
			expectedLabelRule: &labeler.LabelRule{
				ID:    "keyspaces/4242",
				Index: 0,
				Labels: []labeler.RegionLabel{
					{
						Key:   "id",
						Value: "4242",
					},
				},
				RuleType: "key-range",
				Data: []any{
					map[string]any{
						"start_key": hex.EncodeToString(codec.EncodeBytes([]byte{'r', 0, 0x10, 0x92})),
						"end_key":   hex.EncodeToString(codec.EncodeBytes([]byte{'r', 0, 0x10, 0x93})),
					},
					map[string]any{
						"start_key": hex.EncodeToString(codec.EncodeBytes([]byte{'x', 0, 0x10, 0x92})),
						"end_key":   hex.EncodeToString(codec.EncodeBytes([]byte{'x', 0, 0x10, 0x93})),
					},
				},
			},
		},
		{
			id:      0,
			skipRaw: true,
			expectedLabelRule: &labeler.LabelRule{
				ID:    "keyspaces/0",
				Index: 0,
				Labels: []labeler.RegionLabel{
					{
						Key:   "id",
						Value: "0",
					},
				},
				RuleType: "key-range",
				Data: []any{
					map[string]any{
						"start_key": hex.EncodeToString(codec.EncodeBytes([]byte{'x', 0, 0, 0})),
						"end_key":   hex.EncodeToString(codec.EncodeBytes([]byte{'x', 0, 0, 1})),
					},
				},
			},
		},
		{
			id:      4242,
			skipRaw: true,
			expectedLabelRule: &labeler.LabelRule{
				ID:    "keyspaces/4242",
				Index: 0,
				Labels: []labeler.RegionLabel{
					{
						Key:   "id",
						Value: "4242",
					},
				},
				RuleType: "key-range",
				Data: []any{
					map[string]any{
						"start_key": hex.EncodeToString(codec.EncodeBytes([]byte{'x', 0, 0x10, 0x92})),
						"end_key":   hex.EncodeToString(codec.EncodeBytes([]byte{'x', 0, 0x10, 0x93})),
					},
				},
			},
		},
	}
	for _, testCase := range testCases {
		re.Equal(testCase.expectedLabelRule, makeLabelRule(testCase.id, testCase.skipRaw))
	}
}