package stacks

import (
	"net/http"
	"path"

	httperror "github.com/portainer/libhttp/error"
	"github.com/portainer/libhttp/request"
	"github.com/portainer/libhttp/response"
	portainer "github.com/portainer/portainer/api"
	bolterrors "github.com/portainer/portainer/api/bolt/errors"
	"github.com/portainer/portainer/api/http/errors"
	"github.com/portainer/portainer/api/http/security"
	"github.com/portainer/portainer/api/internal/stackutils"
)

type stackFileResponse struct {
	// Content of the Stack file
	StackFileContent string `json:"StackFileContent" example:"version: 3\n services:\n web:\n image:nginx"`
}

// @id StackFileInspect
// @summary Retrieve the content of the Stack file for the specified stack
// @description Get Stack file content.
// @description **Access policy**: restricted
// @tags stacks
// @security jwt
// @produce json
// @param id path int true "Stack identifier"
// @success 200 {object} stackFileResponse "Success"
// @failure 400 "Invalid request"
// @failure 403 "Permission denied"
// @failure 404 "Stack not found"
// @failure 500 "Server error"
// @router /stacks/{id}/file [get]
func (handler *Handler) stackFile(w http.ResponseWriter, r *http.Request) *httperror.HandlerError {
	stackID, err := request.RetrieveNumericRouteVariableValue(r, "id")
	if err != nil {
		return &httperror.HandlerError{http.StatusBadRequest, "Invalid stack identifier route variable", err}
	}

	stack, err := handler.DataStore.Stack().Stack(portainer.StackID(stackID))
	if err == bolterrors.ErrObjectNotFound {
		return &httperror.HandlerError{http.StatusNotFound, "Unable to find a stack with the specified identifier inside the database", err}
	} else if err != nil {
		return &httperror.HandlerError{http.StatusInternalServerError, "Unable to find a stack with the specified identifier inside the database", err}
	}

	securityContext, err := security.RetrieveRestrictedRequestContext(r)
	if err != nil {
		return &httperror.HandlerError{http.StatusInternalServerError, "Unable to retrieve info from request context", err}
	}

	endpoint, err := handler.DataStore.Endpoint().Endpoint(stack.EndpointID)
	if err == bolterrors.ErrObjectNotFound {
		if !securityContext.IsAdmin {
			return &httperror.HandlerError{http.StatusNotFound, "Unable to find an endpoint with the specified identifier inside the database", err}
		}
	} else if err != nil {
		return &httperror.HandlerError{http.StatusInternalServerError, "Unable to find an endpoint with the specified identifier inside the database", err}
	}

	if endpoint != nil {
		err = handler.requestBouncer.AuthorizedEndpointOperation(r, endpoint)
		if err != nil {
			return &httperror.HandlerError{http.StatusForbidden, "Permission denied to access endpoint", err}
		}

		resourceControl, err := handler.DataStore.ResourceControl().ResourceControlByResourceIDAndType(stackutils.ResourceControlID(stack.EndpointID, stack.Name), portainer.StackResourceControl)
		if err != nil {
			return &httperror.HandlerError{http.StatusInternalServerError, "Unable to retrieve a resource control associated to the stack", err}
		}

		access, err := handler.userCanAccessStack(securityContext, endpoint.ID, resourceControl)
		if err != nil {
			return &httperror.HandlerError{http.StatusInternalServerError, "Unable to verify user authorizations to validate stack access", err}
		}
		if !access {
			return &httperror.HandlerError{http.StatusForbidden, "Access denied to resource", errors.ErrResourceAccessDenied}
		}
	}

	stackFileContent, err := handler.FileService.GetFileContent(path.Join(stack.ProjectPath, stack.EntryPoint))
	if err != nil {
		return &httperror.HandlerError{http.StatusInternalServerError, "Unable to retrieve Compose file from disk", err}
	}

	return response.JSON(w, &stackFileResponse{StackFileContent: string(stackFileContent)})
}
