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"
)

type fakeMembershipChecker struct {
	isMember bool
	err      error
}

func (f *fakeMembershipChecker) IsMember(_ context.Context, _, _ bson.ObjectID) (bool, error) {
	return f.isMember, f.err
}

func TestScopedAuthorizer_Authorize(t *testing.T) {
	caller := bson.NewObjectID()
	other := bson.NewObjectID()
	org := bson.NewObjectID()
	object := bson.NewObjectID()
	policy := bson.NewObjectID()

	base := func(kind model.OwnerKind, owner bson.ObjectID) ScopedAccessParams {
		return ScopedAccessParams{
			Service:   mservice.Recipients,
			PolicyRef: policy,
			CallerRef: caller,
			OrgRef:    org,
			ObjectRef: object,
			OwnerKind: kind,
			OwnerRef:  owner,
			Action:    model.ActionRead,
		}
	}

	t.Run("membership checker error propagates for org-owned resource and is not masked as denied", func(t *testing.T) {
		boom := merrors.Define("checker down")
		a := &ScopedAuthorizer{Logger: zap.NewNop(),
			Membership: &fakeMembershipChecker{err: boom},
			Enforcer:   &fakeEnforcer{},
		}
		err := a.Authorize(context.Background(), base(model.OwnerKindOrganization, org))
		if !errors.Is(err, boom) {
			t.Fatalf("expected underlying error, got %v", err)
		}
		if errors.Is(err, merrors.ErrAccessDenied) {
			t.Fatal("checker error must not be reported as access denied")
		}
	})

	t.Run("non-member owning account-owned resource is allowed", func(t *testing.T) {
		a := &ScopedAuthorizer{Logger: zap.NewNop(),
			Membership: &fakeMembershipChecker{isMember: false},
			Enforcer:   &fakeEnforcer{},
		}
		if err := a.Authorize(context.Background(), base(model.OwnerKindAccount, caller)); err != nil {
			t.Fatalf("expected allow for personal resource owner regardless of membership, got %v", err)
		}
	})

	t.Run("non-member is denied for org-owned resource", func(t *testing.T) {
		a := &ScopedAuthorizer{Logger: zap.NewNop(),
			Membership: &fakeMembershipChecker{isMember: false},
			Enforcer:   &fakeEnforcer{allow: true},
		}
		err := a.Authorize(context.Background(), base(model.OwnerKindOrganization, org))
		if !errors.Is(err, merrors.ErrAccessDenied) {
			t.Fatalf("expected access denied for non-member on org resource, got %v", err)
		}
	})

	t.Run("member owning account-owned resource is allowed", func(t *testing.T) {
		a := &ScopedAuthorizer{Logger: zap.NewNop(),
			Membership: &fakeMembershipChecker{isMember: true},
			Enforcer:   &fakeEnforcer{},
		}
		if err := a.Authorize(context.Background(), base(model.OwnerKindAccount, caller)); err != nil {
			t.Fatalf("expected allow, got %v", err)
		}
	})

	t.Run("member accessing another account's resource is denied", func(t *testing.T) {
		a := &ScopedAuthorizer{Logger: zap.NewNop(),
			Membership: &fakeMembershipChecker{isMember: true},
			Enforcer:   &fakeEnforcer{},
		}
		err := a.Authorize(context.Background(), base(model.OwnerKindAccount, other))
		if !errors.Is(err, merrors.ErrAccessDenied) {
			t.Fatalf("expected access denied, got %v", err)
		}
	})

	t.Run("member with org-owned resource allowed when enforcer approves", func(t *testing.T) {
		a := &ScopedAuthorizer{Logger: zap.NewNop(),
			Membership: &fakeMembershipChecker{isMember: true},
			Enforcer:   &fakeEnforcer{allow: true},
		}
		if err := a.Authorize(context.Background(), base(model.OwnerKindOrganization, org)); err != nil {
			t.Fatalf("expected allow, got %v", err)
		}
	})

	t.Run("member with org-owned resource denied when enforcer refuses", func(t *testing.T) {
		a := &ScopedAuthorizer{Logger: zap.NewNop(),
			Membership: &fakeMembershipChecker{isMember: true},
			Enforcer:   &fakeEnforcer{allow: false},
		}
		err := a.Authorize(context.Background(), base(model.OwnerKindOrganization, org))
		if !errors.Is(err, merrors.ErrAccessDenied) {
			t.Fatalf("expected access denied, got %v", err)
		}
	})

	t.Run("enforcer error propagates and is not masked as denied", func(t *testing.T) {
		boom := merrors.Define("policy backend down")
		a := &ScopedAuthorizer{Logger: zap.NewNop(),
			Membership: &fakeMembershipChecker{isMember: true},
			Enforcer:   &fakeEnforcer{err: boom},
		}
		err := a.Authorize(context.Background(), base(model.OwnerKindOrganization, org))
		if !errors.Is(err, boom) {
			t.Fatalf("expected underlying error, got %v", err)
		}
		if errors.Is(err, merrors.ErrAccessDenied) {
			t.Fatal("enforcer error must not be reported as access denied")
		}
	})

	t.Run("unknown owner kind is denied", func(t *testing.T) {
		a := &ScopedAuthorizer{Logger: zap.NewNop(),
			Membership: &fakeMembershipChecker{isMember: true},
			Enforcer:   &fakeEnforcer{allow: true},
		}
		err := a.Authorize(context.Background(), base(model.OwnerKind("garbage"), caller))
		if !errors.Is(err, merrors.ErrAccessDenied) {
			t.Fatalf("expected access denied for unknown owner kind, got %v", err)
		}
	})
}