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#' Place nodes on their geographical space
#'
#' This layout is built for objects of class `sfnetwork` and is meant to
#' plot a graph on its geographical space, by extracting its X and Y coordinates
#'
#' @param graph An sfnetwork object
#' @param circular ignored
#'
#' @importFrom tidygraph as_tbl_graph
#'
#' @return A data.frame with the columns `x`, `y`, `circular`.
#'
#' @family layout_tbl_graph_*
layout_tbl_graph_sf <- function(graph, circular = FALSE) {
# Check the presence of sf.
check_installed("sf")
# Check if network is an sfnetwork
if (!inherits(graph, "sfnetwork")) {
cli::cli_abort("The 'sf' layout needs an {.cls sfnetwork} graph.")
}
# Extract X and Y coordinates from the nodes
graph <- activate(graph, "nodes")
x <- sf::st_coordinates(graph)[,"X"]
y <- sf::st_coordinates(graph)[,"Y"]
# Create layout data frame
nodes <- data_frame0(x = x, y = y, circular = FALSE)
# Convert to tbl_graph to 'unstick' geometry column
extra_data <- as_tibble(as_tbl_graph(graph), active = "nodes")
nodes <- combine_layout_nodes(nodes, extra_data)
attr(nodes, 'graph') <- graph
nodes
}
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