package command

import (
	"context"

	"github.com/zitadel/zitadel/internal/api/authz"
	"github.com/zitadel/zitadel/internal/domain"
	"github.com/zitadel/zitadel/internal/eventstore"
	"github.com/zitadel/zitadel/internal/repository/project"
	"github.com/zitadel/zitadel/internal/v2/user"
	"github.com/zitadel/zitadel/internal/zerrors"
)

type PermissionCheck func(resourceOwner, aggregateID string) error

func (c *Commands) newPermissionCheck(ctx context.Context, permission string, aggregateType eventstore.AggregateType) PermissionCheck {
	return func(resourceOwner, aggregateID string) error {
		if aggregateID == "" {
			return zerrors.ThrowInternal(nil, "COMMAND-ulBlS", "Errors.IDMissing")
		}
		// For example if a write model didn't query any events, the resource owner is probably empty.
		// In this case, we have to query an event on the given aggregate to get the resource owner.
		if resourceOwner == "" {
			r := NewResourceOwnerModel(authz.GetInstance(ctx).InstanceID(), aggregateType, aggregateID)
			err := c.eventstore.FilterToQueryReducer(ctx, r)
			if err != nil {
				return err
			}
			resourceOwner = r.resourceOwner
		}
		if resourceOwner == "" {
			return zerrors.ThrowNotFound(nil, "COMMAND-4g3xq", "Errors.NotFound")
		}
		return c.checkPermission(ctx, permission, resourceOwner, aggregateID)
	}
}

func (c *Commands) checkPermissionOnUser(ctx context.Context, permission string) PermissionCheck {
	return func(resourceOwner, aggregateID string) error {
		if aggregateID != "" && aggregateID == authz.GetCtxData(ctx).UserID {
			return nil
		}
		return c.newPermissionCheck(ctx, permission, user.AggregateType)(resourceOwner, aggregateID)
	}
}

func (c *Commands) NewPermissionCheckUserWrite(ctx context.Context) PermissionCheck {
	return c.checkPermissionOnUser(ctx, domain.PermissionUserWrite)
}

func (c *Commands) checkPermissionDeleteUser(ctx context.Context, resourceOwner, userID string) error {
	return c.checkPermissionOnUser(ctx, domain.PermissionUserDelete)(resourceOwner, userID)
}

func (c *Commands) checkPermissionUpdateUser(ctx context.Context, resourceOwner, userID string) error {
	return c.NewPermissionCheckUserWrite(ctx)(resourceOwner, userID)
}

func (c *Commands) checkPermissionUpdateUserCredentials(ctx context.Context, resourceOwner, userID string) error {
	return c.checkPermissionOnUser(ctx, domain.PermissionUserCredentialWrite)(resourceOwner, userID)
}

func (c *Commands) checkPermissionDeleteProject(ctx context.Context, resourceOwner, projectID string) error {
	return c.newPermissionCheck(ctx, domain.PermissionProjectDelete, project.AggregateType)(resourceOwner, projectID)
}

func (c *Commands) checkPermissionUpdateProject(ctx context.Context, resourceOwner, projectID string) error {
	return c.newPermissionCheck(ctx, domain.PermissionProjectWrite, project.AggregateType)(resourceOwner, projectID)
}

func (c *Commands) checkPermissionWriteProjectGrant(ctx context.Context, resourceOwner, projectGrantID string) error {
	return c.newPermissionCheck(ctx, domain.PermissionProjectGrantWrite, project.AggregateType)(resourceOwner, projectGrantID)
}