package ape

import (
	"context"
	"encoding/hex"
	"fmt"
	"testing"

	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/checksum"
	cid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/container/id"
	objectSDK "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object"
	oid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object/id"
	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/user"
	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/version"
	"git.frostfs.info/TrueCloudLab/policy-engine/pkg/chain"
	policyengine "git.frostfs.info/TrueCloudLab/policy-engine/pkg/engine"
	"git.frostfs.info/TrueCloudLab/policy-engine/pkg/engine/inmemory"
	nativeschema "git.frostfs.info/TrueCloudLab/policy-engine/schema/native"
	"github.com/stretchr/testify/require"
)

type headerProviderMock struct {
	m map[oid.Address]*objectSDK.Object
}

var _ HeaderProvider = (*headerProviderMock)(nil)

func (h *headerProviderMock) addHeader(c cid.ID, o oid.ID, header *objectSDK.Object) {
	var addr oid.Address
	addr.SetContainer(c)
	addr.SetObject(o)
	h.m[addr] = header
}

func (h *headerProviderMock) GetHeader(_ context.Context, c cid.ID, o oid.ID) (*objectSDK.Object, error) {
	var addr oid.Address
	addr.SetContainer(c)
	addr.SetObject(o)
	obj, ok := h.m[addr]
	if !ok {
		return nil, fmt.Errorf("address not found")
	}
	return obj, nil
}

func newHeaderProviderMock() *headerProviderMock {
	return &headerProviderMock{
		m: make(map[oid.Address]*objectSDK.Object),
	}
}

func newContainerIDSDK(t *testing.T, encodedCID string) cid.ID {
	var cnr cid.ID
	require.NoError(t, cnr.DecodeString(encodedCID))
	return cnr
}

func newObjectIDSDK(t *testing.T, encodedOID *string) *oid.ID {
	if encodedOID == nil {
		return nil
	}
	obj := new(oid.ID)
	require.NoError(t, obj.DecodeString(*encodedOID))
	return obj
}

type headerObjectSDKParams struct {
	majorVersion, minorVersion uint32
	owner                      user.ID
	epoch                      uint64
	payloadSize                uint64
	typ                        objectSDK.Type
	payloadChecksum            checksum.Checksum
	payloadHomomorphicHash     checksum.Checksum
	attributes                 []struct {
		key string
		val string
	}
}

func stringPtr(s string) *string {
	return &s
}

func newHeaderObjectSDK(t *testing.T, cnr cid.ID, oid *oid.ID, headerObjSDK *headerObjectSDKParams) *objectSDK.Object {
	objSDK := objectSDK.New()
	objSDK.SetContainerID(cnr)
	if oid != nil {
		objSDK.SetID(*oid)
	}
	if headerObjSDK == nil {
		return objSDK
	}
	ver := new(version.Version)
	ver.SetMajor(headerObjSDK.majorVersion)
	ver.SetMinor(headerObjSDK.minorVersion)
	objSDK.SetVersion(ver)
	objSDK.SetCreationEpoch(headerObjSDK.epoch)
	objSDK.SetOwnerID(headerObjSDK.owner)
	objSDK.SetPayloadSize(headerObjSDK.payloadSize)
	objSDK.SetType(headerObjSDK.typ)
	objSDK.SetPayloadChecksum(headerObjSDK.payloadChecksum)
	objSDK.SetPayloadHomomorphicHash(headerObjSDK.payloadHomomorphicHash)

	var attrs []objectSDK.Attribute
	for _, attr := range headerObjSDK.attributes {
		attrSDK := objectSDK.NewAttribute()
		attrSDK.SetKey(attr.key)
		attrSDK.SetValue(attr.val)
		attrs = append(attrs, *attrSDK)
	}
	objSDK.SetAttributes(attrs...)

	return objSDK
}

type testHeader struct {
	headerObjSDK *headerObjectSDKParams

	// If fromHeaderProvider is set, then running test should
	// consider that a header is recieved from a header provider.
	fromHeaderProvider bool

	// If fromHeaderProvider is set, then running test should
	// consider that a header is recieved from a message header.
	fromRequestResponseHeader bool
}

var (
	methodsRequiredOID = []string{
		nativeschema.MethodGetObject,
		nativeschema.MethodHeadObject,
		nativeschema.MethodRangeObject,
		nativeschema.MethodHashObject,
		nativeschema.MethodDeleteObject,
	}

	methodsOptionalOID = []string{
		nativeschema.MethodSearchObject, nativeschema.MethodPutObject,
	}

	namespace = "test_namespace"

	containerID = "73tQMTYyUkTgmvPR1HWib6pndbhSoBovbnMF7Pws8Rcy"

	objectID = "BzQw5HH3feoxFDD5tCT87Y1726qzgLfxEE7wgtoRzB3R"

	role = "Container"

	senderKey = hex.EncodeToString([]byte{1, 0, 0, 1})
)

func TestAPECheck(t *testing.T) {
	for _, test := range []struct {
		name           string
		container      string
		object         *string
		methods        []string
		header         testHeader
		containerRules []chain.Rule
		expectAPEErr   bool
	}{
		{
			name:      "oid required requests are allowed",
			container: containerID,
			object:    stringPtr(objectID),
			methods:   methodsRequiredOID,
			containerRules: []chain.Rule{
				{
					Status:  chain.Allow,
					Actions: chain.Actions{Names: methodsRequiredOID},
					Resources: chain.Resources{
						Names: []string{fmt.Sprintf(nativeschema.ResourceFormatRootContainerObject, containerID, objectID)},
					},
				},
			},
		},
		{
			name:      "oid optional requests are allowed",
			container: containerID,
			methods:   methodsOptionalOID,
			containerRules: []chain.Rule{
				{
					Status:  chain.Allow,
					Actions: chain.Actions{Names: methodsOptionalOID},
					Resources: chain.Resources{
						Names: []string{fmt.Sprintf(nativeschema.ResourceFormatRootContainerObjects, containerID)},
					},
				},
			},
		},
		{
			name:      "oid required requests are denied",
			container: containerID,
			object:    stringPtr(objectID),
			methods:   methodsRequiredOID,
			containerRules: []chain.Rule{
				{
					Status:  chain.AccessDenied,
					Actions: chain.Actions{Names: methodsRequiredOID},
					Resources: chain.Resources{
						Names: []string{fmt.Sprintf(nativeschema.ResourceFormatRootContainerObject, containerID, objectID)},
					},
				},
			},
			expectAPEErr: true,
		},
		{
			name:      "oid required requests are denied by an attribute",
			container: containerID,
			object:    stringPtr(objectID),
			methods:   methodsRequiredOID,
			header: testHeader{
				headerObjSDK: &headerObjectSDKParams{
					attributes: []struct {
						key string
						val string
					}{
						{
							key: "attr1",
							val: "attribute_value",
						},
					},
				},
				fromHeaderProvider: true,
			},
			containerRules: []chain.Rule{
				{
					Status:  chain.AccessDenied,
					Actions: chain.Actions{Names: methodsRequiredOID},
					Resources: chain.Resources{
						Names: []string{fmt.Sprintf(nativeschema.ResourceFormatRootContainerObject, containerID, objectID)},
					},
					Any: true,
					Condition: []chain.Condition{
						{
							Op:     chain.CondStringLike,
							Object: chain.ObjectResource,
							Key:    "attr1",
							Value:  "attribute*",
						},
					},
				},
			},
			expectAPEErr: true,
		},
		{
			name:      "oid required requests are denied by sender",
			container: containerID,
			object:    stringPtr(objectID),
			methods:   methodsRequiredOID,
			header: testHeader{
				headerObjSDK: &headerObjectSDKParams{
					attributes: []struct {
						key string
						val string
					}{
						{
							key: "attr1",
							val: "attribute_value",
						},
					},
				},
				fromHeaderProvider: true,
			},
			containerRules: []chain.Rule{
				{
					Status:  chain.AccessDenied,
					Actions: chain.Actions{Names: methodsRequiredOID},
					Resources: chain.Resources{
						Names: []string{fmt.Sprintf(nativeschema.ResourceFormatRootContainerObject, containerID, objectID)},
					},
					Any: true,
					Condition: []chain.Condition{
						{
							Op:     chain.CondStringLike,
							Object: chain.ObjectRequest,
							Key:    nativeschema.PropertyKeyActorPublicKey,
							Value:  senderKey,
						},
					},
				},
			},
			expectAPEErr: true,
		},
		{
			name:      "optional oid requests reached quota limit by an attribute",
			container: containerID,
			methods:   methodsOptionalOID,
			header: testHeader{
				headerObjSDK: &headerObjectSDKParams{
					payloadSize: 1000,
				},
				fromRequestResponseHeader: true,
			},
			containerRules: []chain.Rule{
				{
					Status:  chain.QuotaLimitReached,
					Actions: chain.Actions{Names: methodsOptionalOID},
					Resources: chain.Resources{
						Names: []string{fmt.Sprintf(nativeschema.ResourceFormatRootContainerObjects, containerID)},
					},
					Any: true,
					Condition: []chain.Condition{
						{
							Op:     chain.CondStringEquals,
							Object: chain.ObjectResource,
							Key:    nativeschema.PropertyKeyObjectPayloadLength,
							Value:  "1000",
						},
					},
				},
			},
			expectAPEErr: true,
		},
	} {
		t.Run(test.name, func(t *testing.T) {
			for _, method := range test.methods {
				t.Run(method, func(t *testing.T) {
					headerProvider := newHeaderProviderMock()

					cnr := newContainerIDSDK(t, test.container)
					obj := newObjectIDSDK(t, test.object)

					ls := inmemory.NewInmemoryLocalStorage()
					ms := inmemory.NewInmemoryMorphRuleChainStorage()

					ls.AddOverride(chain.Ingress, policyengine.ContainerTarget(test.container), &chain.Chain{
						Rules:     test.containerRules,
						MatchType: chain.MatchTypeFirstMatch,
					})

					router := policyengine.NewDefaultChainRouterWithLocalOverrides(ms, ls)

					checker := NewChecker(router, headerProvider)

					prm := Prm{
						Method:    method,
						Container: cnr,
						Object:    obj,
						Role:      role,
						SenderKey: senderKey,
					}

					var headerObjSDK *objectSDK.Object
					if test.header.headerObjSDK != nil {
						headerObjSDK = newHeaderObjectSDK(t, cnr, obj, test.header.headerObjSDK)
						if test.header.fromHeaderProvider {
							require.NotNil(t, obj, "oid is required if a header is expected to be found in header provider")
							headerProvider.addHeader(cnr, *obj, headerObjSDK)
						} else if test.header.fromRequestResponseHeader {
							prm.Header = headerObjSDK.ToV2().GetHeader()
						}
					}

					err := checker.CheckAPE(context.Background(), prm)
					if test.expectAPEErr {
						require.Error(t, err)
					} else {
						require.NoError(t, err)
					}
				})
			}
		})
	}
}