package auth

import (
	"context"
	"errors"
	"testing"

	"git.sendico.io/tech/sxchnge/bff/pkg/merrors"
	"git.sendico.io/tech/sxchnge/bff/pkg/model"
	"git.sendico.io/tech/sxchnge/bff/pkg/mservice"
	"go.mongodb.org/mongo-driver/v2/bson"
	"go.uber.org/zap"
)

// testOwned is a minimal model.OwnerBound used exclusively by ScopedDB tests.
type testOwned struct {
	id       bson.ObjectID
	orgRef   bson.ObjectID
	kind     model.OwnerKind
	ownerRef bson.ObjectID
}

func (o *testOwned) GetID() *bson.ObjectID                { return &o.id }
func (o *testOwned) SetID(id bson.ObjectID)               { o.id = id }
func (o *testOwned) Update()                              {}
func (o *testOwned) Collection() string                   { return "test_owned" }
func (o *testOwned) GetOrganizationRef() bson.ObjectID    { return o.orgRef }
func (o *testOwned) SetOrganizationRef(ref bson.ObjectID) { o.orgRef = ref }
func (o *testOwned) GetOwnerKind() model.OwnerKind        { return o.kind }
func (o *testOwned) GetOwnerRef() bson.ObjectID           { return o.ownerRef }

var _ model.OwnerBound = (*testOwned)(nil)

// fakeOwnerLoader returns the pre-built object or the configured error.
type fakeOwnerLoader struct {
	obj *testOwned
	err error
}

func (f *fakeOwnerLoader) Get(_ context.Context, _ bson.ObjectID, result *testOwned) error {
	if f.err != nil {
		return f.err
	}
	*result = *f.obj
	return nil
}

// fakeMembership controls whether IsMember returns true/false/error.
type fakeMembership struct {
	member bool
	err    error
	called bool
}

func (f *fakeMembership) IsMember(_ context.Context, _, _ bson.ObjectID) (bool, error) {
	f.called = true
	return f.member, f.err
}

func newTestScopedDB(loader *fakeOwnerLoader, membership *fakeMembership, enf Enforcer) *ScopedDB[*testOwned] {
	authorizer := &ScopedAuthorizer{
		Logger:     zap.NewNop(),
		Membership: membership,
		Enforcer:   enf,
	}
	return &ScopedDB[*testOwned]{
		DB:           loader,
		Logger:       zap.NewNop(),
		Authorizer:   authorizer,
		OrgPolicyRef: bson.NewObjectID(),
		Collection:   mservice.Type("test_owned"),
		New:          func() *testOwned { return &testOwned{} },
	}
}

func TestScopedDB_PersonalOwner_Allowed(t *testing.T) {
	caller := bson.NewObjectID()
	objectRef := bson.NewObjectID()
	obj := &testOwned{
		id:       objectRef,
		orgRef:   bson.NewObjectID(),
		kind:     model.OwnerKindAccount,
		ownerRef: caller, // owner == caller
	}
	enf := &fakeEnforcer{}
	db := newTestScopedDB(&fakeOwnerLoader{obj: obj}, &fakeMembership{member: true}, enf)

	result, err := db.LoadAndEnforce(context.Background(), caller, objectRef, model.ActionRead)
	if err != nil {
		t.Fatalf("expected allow, got %v", err)
	}
	if result == nil {
		t.Fatal("expected non-nil result on success")
	}
	if enf.called {
		t.Fatal("personal access must not consult the enforcer")
	}
}

func TestScopedDB_PersonalOwner_Denied(t *testing.T) {
	caller := bson.NewObjectID()
	other := bson.NewObjectID()
	objectRef := bson.NewObjectID()
	obj := &testOwned{
		id:       objectRef,
		orgRef:   bson.NewObjectID(),
		kind:     model.OwnerKindAccount,
		ownerRef: other, // owner != caller
	}
	enf := &fakeEnforcer{}
	db := newTestScopedDB(&fakeOwnerLoader{obj: obj}, &fakeMembership{member: true}, enf)

	_, err := db.LoadAndEnforce(context.Background(), caller, objectRef, model.ActionRead)
	if !errors.Is(err, merrors.ErrAccessDenied) {
		t.Fatalf("expected access denied, got %v", err)
	}
	if enf.called {
		t.Fatal("personal access must not consult the enforcer")
	}
}

func TestScopedDB_OrgOwner_Allowed(t *testing.T) {
	caller := bson.NewObjectID()
	orgRef := bson.NewObjectID()
	objectRef := bson.NewObjectID()
	obj := &testOwned{
		id:       objectRef,
		orgRef:   orgRef,
		kind:     model.OwnerKindOrganization,
		ownerRef: orgRef,
	}
	enf := &fakeEnforcer{allow: true}
	db := newTestScopedDB(&fakeOwnerLoader{obj: obj}, &fakeMembership{member: true}, enf)

	result, err := db.LoadAndEnforce(context.Background(), caller, objectRef, model.ActionRead)
	if err != nil {
		t.Fatalf("expected allow, got %v", err)
	}
	if result == nil {
		t.Fatal("expected non-nil result on success")
	}
	if !enf.called {
		t.Fatal("org access must consult the enforcer")
	}
}

func TestScopedDB_OrgOwner_Denied(t *testing.T) {
	caller := bson.NewObjectID()
	orgRef := bson.NewObjectID()
	objectRef := bson.NewObjectID()
	obj := &testOwned{
		id:       objectRef,
		orgRef:   orgRef,
		kind:     model.OwnerKindOrganization,
		ownerRef: orgRef,
	}
	enf := &fakeEnforcer{allow: false}
	db := newTestScopedDB(&fakeOwnerLoader{obj: obj}, &fakeMembership{member: true}, enf)

	_, err := db.LoadAndEnforce(context.Background(), caller, objectRef, model.ActionRead)
	if !errors.Is(err, merrors.ErrAccessDenied) {
		t.Fatalf("expected access denied, got %v", err)
	}
	if !enf.called {
		t.Fatal("org access must consult the enforcer")
	}
}

func TestScopedDB_OrgOwner_EnforcerError_Propagated(t *testing.T) {
	boom := merrors.Define("enforcer backend down")
	caller := bson.NewObjectID()
	orgRef := bson.NewObjectID()
	objectRef := bson.NewObjectID()
	obj := &testOwned{
		id:       objectRef,
		orgRef:   orgRef,
		kind:     model.OwnerKindOrganization,
		ownerRef: orgRef,
	}
	enf := &fakeEnforcer{err: boom}
	db := newTestScopedDB(&fakeOwnerLoader{obj: obj}, &fakeMembership{member: true}, enf)

	_, err := db.LoadAndEnforce(context.Background(), caller, objectRef, model.ActionRead)
	if !errors.Is(err, boom) {
		t.Fatalf("expected underlying error propagated, got %v", err)
	}
	if errors.Is(err, merrors.ErrAccessDenied) {
		t.Fatal("enforcer internal error must not be masked as access denied")
	}
}

func TestScopedDB_DBError_Propagated(t *testing.T) {
	dbErr := merrors.Define("mongo unavailable")
	db := newTestScopedDB(&fakeOwnerLoader{err: dbErr}, &fakeMembership{member: true}, &fakeEnforcer{})

	_, err := db.LoadAndEnforce(context.Background(), bson.NewObjectID(), bson.NewObjectID(), model.ActionRead)
	if !errors.Is(err, dbErr) {
		t.Fatalf("expected DB error propagated, got %v", err)
	}
}

// TestScopedDB_PersonalOwner_NonMember_Denied is the main regression case:
// even when ownerRef == callerRef, a non-member of the organization must be
// denied before ownership is checked, so the tenant boundary is enforced.
// TestScopedDB_PersonalOwner_NonMember_Allowed: personal resource, caller is the
// owner but is NOT a member of the org. Membership is not consulted for
// account-owned resources — ownership alone is sufficient.
func TestScopedDB_PersonalOwner_NonMember_Allowed(t *testing.T) {
	caller := bson.NewObjectID()
	objectRef := bson.NewObjectID()
	obj := &testOwned{
		id:       objectRef,
		orgRef:   bson.NewObjectID(),
		kind:     model.OwnerKindAccount,
		ownerRef: caller, // owner == caller, membership is irrelevant
	}
	membership := &fakeMembership{member: false}
	enf := &fakeEnforcer{}
	db := newTestScopedDB(&fakeOwnerLoader{obj: obj}, membership, enf)

	result, err := db.LoadAndEnforce(context.Background(), caller, objectRef, model.ActionRead)
	if err != nil {
		t.Fatalf("expected allow for personal resource owner regardless of membership, got %v", err)
	}
	if result == nil {
		t.Fatal("expected non-nil result on success")
	}
	if enf.called {
		t.Fatal("enforcer must not be called for account-owned resource")
	}
}

// TestScopedDB_OrgOwner_NonMember_Denied: org-owned object, caller is not a
// member — must be denied before the policy enforcer is consulted.
func TestScopedDB_OrgOwner_NonMember_Denied(t *testing.T) {
	caller := bson.NewObjectID()
	orgRef := bson.NewObjectID()
	objectRef := bson.NewObjectID()
	obj := &testOwned{
		id:       objectRef,
		orgRef:   orgRef,
		kind:     model.OwnerKindOrganization,
		ownerRef: orgRef,
	}
	membership := &fakeMembership{member: false}
	enf := &fakeEnforcer{allow: true} // would allow if reached
	db := newTestScopedDB(&fakeOwnerLoader{obj: obj}, membership, enf)

	_, err := db.LoadAndEnforce(context.Background(), caller, objectRef, model.ActionRead)
	if !errors.Is(err, merrors.ErrAccessDenied) {
		t.Fatalf("expected access denied for non-member org-owned object, got %v", err)
	}
	if enf.called {
		t.Fatal("enforcer must not be called when membership check fails")
	}
}