R/deselect_edges.R

In DiagrammeR: Graph/Network Visualization

#' Deselect any selected edges in a graph
#'
#' @description
#'
#' Deselect edges in a graph object of class `dgr_graph`.
#'
#' @inheritParams render_graph
#' @param edges A vector of edge IDs that should be deselected.
#'
#' @return A graph object of class `dgr_graph`.
#'
#' @examples
#' # Create a graph with
#' # a single path
#' graph <-
#'   create_graph() %>%
#'   add_path(n = 5)
#'
#' # Select edges with IDs `1`
#' # and `3`
#' graph <-
#'   graph %>%
#'   select_edges_by_edge_id(
#'     edges = c(1, 3))
#'
#' # Verify that an edge selection
#' # has been made
#' graph %>% get_selection()
#'
#' # Deselect edge `1`
#' graph <-
#'   graph %>%
#'   select_edges_by_edge_id(
#'     edges = c(1, 3)) %>%
#'   deselect_edges(edges = 1)
#'
#' # Verify that the edge selection
#' # has been made for edges `1` and
#' # `3` and that edge `1` has been
#' # deselected (leaving only `3`)
#' graph %>% get_selection()
#'
#' @export
deselect_edges <- function(
    graph,
    edges
) {

  # Get the time of function start
  time_function_start <- Sys.time()

  # Get the name of the function
  fcn_name <- get_calling_fcn()

  # Validation: Graph object is valid
  if (graph_object_valid(graph) == FALSE) {

    emit_error(
      fcn_name = fcn_name,
      reasons = "The graph object is not valid")
  }

  # If no edge selection available, return graph
  if (graph_contains_edge_selection(graph) == FALSE) {
    return(graph)
  }

  # Extract the graph's edge selection
  graph$edge_selection <-
    graph$edge_selection %>%
    dplyr::filter(!(edge %in% edges))

  # Update the `graph_log` df with an action
  graph$graph_log <-
    add_action_to_log(
      graph_log = graph$graph_log,
      version_id = nrow(graph$graph_log) + 1,
      function_used = fcn_name,
      time_modified = time_function_start,
      duration = graph_function_duration(time_function_start),
      nodes = nrow(graph$nodes_df),
      edges = nrow(graph$edges_df))

  # Write graph backup if the option is set
  if (graph$graph_info$write_backups) {
    save_graph_as_rds(graph = graph)
  }

  graph
}