tidygeocoder: Geocoding Made Easy

Documented in reverse_geo

## IMPORTANT: All new REVERSE batch geocoding functions must be added to reverse_batch_func_map
# the reverse_geo() function references this list to find reverse batch geocoding functions (reverse_batch_geocoding.R)
# maps method names to batch functions
reverse_batch_func_map <- list(
  geocodio = reverse_batch_geocodio,
  here = reverse_batch_here,
  tomtom = reverse_batch_tomtom,
  mapquest = reverse_batch_mapquest,
  bing = reverse_batch_bing
)

# call geo function with progress bar
progress_reverse_geo <- function(pb = NULL, ...) {
  results <- reverse_geo(...)
  if (!is.null(pb)) pb$tick()
  return(results)
}

# Create API parameters for a single set of coordinates (lat, long) based on the
# method. Parameters are placed into the 'custom_query' variable which is a named list
# that is passed directly to the API service.
get_coord_parameters <- function(custom_query, method, lat, long) {
  if (method %in% c("osm", "iq", "geoapify")) {
    custom_query[["lat"]] <- lat
    custom_query[["lon"]] <- long
  } else if (method %in% c("geocodio", "opencage")) {
    custom_query[["q"]] <- paste0(as.character(lat), ",", as.character(long))
  } else if (method == "google") {
    custom_query[["latlng"]] <- paste0(as.character(lat), ",", as.character(long))
  } else if (method == "mapbox") {
    custom_query[["to_url"]] <-
      paste0(as.character(long), ",", as.character(lat))
  } else if (method == "here") {
    custom_query[["at"]] <-
      paste0(as.character(lat), ",", as.character(long))
  } else if (method == "tomtom") {
    custom_query[["to_url"]] <-
      paste0(as.character(lat), ",", as.character(long))
  } else if (method == "mapquest") {
    custom_query[["location"]] <- paste0(as.character(lat), ",", as.character(long))
  } else if (method == "bing") {
    custom_query[["to_url"]] <- paste0("/", as.character(lat), ",", as.character(long))
  } else if (method == "arcgis") {
    custom_query[["location"]] <-
      paste0(as.character(long), ",", as.character(lat))
  } else {
    stop("Invalid method. See ?reverse_geo", call. = FALSE)
  }
  return(custom_query)
}


#' Reverse geocode coordinates
#'
#' @description
#' Reverse geocodes geographic coordinates (latitude and longitude) given as numeric values.
#' Latitude and longitude inputs are limited to possible values. Latitudes must be between -90 and 90 and
#' longitudes must be between -180 and 180. Invalid values will not be sent to the geocoding service.
#' The [reverse_geocode] function utilizes this function on coordinates contained in dataframes.
#' See example usage in `vignette("tidygeocoder")`.
#'
#' Refer to [api_parameter_reference],
#' [min_time_reference], and [batch_limit_reference] for more details on
#' geocoding service parameters and usage.
#'
#' This function uses the [get_api_query], [query_api], and
#' [extract_reverse_results] functions to create, execute, and parse geocoder
#' API queries.
#'
#' @param lat latitude values (input data)
#' @param long longitude values (input data)
#' @param method `r get_method_documentation(reverse = TRUE)`
#'
#' @param address name of the address column (in the output data)
#' @param limit `r get_limit_documentation(reverse = TRUE, df_input = FALSE)`
#'
#' @param full_results `r get_full_results_documentation(reverse = TRUE)`
#' @param mode `r get_mode_documentation(reverse = TRUE)`
#' @param return_coords return input coordinates with results if TRUE. Note that
#'    most services return the input coordinates with `full_results = TRUE` and setting
#'    `return_coords` to FALSE does not prevent this.
#'
#' @param batch_limit `r get_batch_limit_documentation(reverse = TRUE)`
#' @inheritParams geo
#'
#' @inherit geo return
#' @examples
#' \donttest{
#' options(tidygeocoder.progress_bar = FALSE)
#'
#' reverse_geo(lat = 38.895865, long = -77.0307713, method = "osm")
#'
#' reverse_geo(
#'   lat = c(38.895865, 43.6534817, 300),
#'   long = c(-77.0307713, -79.3839347, 600),
#'   method = "osm", full_results = TRUE
#' )
#' }
#' @seealso [reverse_geocode] [api_parameter_reference] [min_time_reference] [batch_limit_reference]
#' @export
reverse_geo <-
  function(lat,
           long,
           method = "osm",
           address = "address",
           limit = 1,
           full_results = FALSE,
           mode = "",
           unique_only = FALSE,
           return_coords = TRUE,
           min_time = NULL,
           progress_bar = show_progress_bar(),
           quiet = getOption("tidygeocoder.quiet", FALSE),
           api_url = NULL,
           timeout = 20,
           flatten = TRUE,
           batch_limit = NULL,
           verbose = getOption("tidygeocoder.verbose", FALSE),
           no_query = FALSE,
           custom_query = list(),
           api_options = list()
           ) {

    # NSE eval
    address <- rm_quote(deparse(substitute(address)))

    # set the api_optons[["init"]] parameter if it is NULL
    api_options <- initialize_init(api_options)

    # apply api options defaults for options not specified by the user
    api_options <- apply_api_options_defaults(method, api_options)

    # capture all function arguments including default values as a named list.
    # IMPORTANT: make sure to put this statement before any other variables are defined in the function
    all_args <- as.list(environment())
    all_args$api_options[["init"]] <- FALSE # any following queries are not the initial query
    # remove NULL arguments
    all_args[sapply(all_args, is.null)] <- NULL

    # Check argument inputs
    stopifnot(
      is.logical(verbose), is.logical(no_query), is.logical(flatten),
      is.logical(full_results), is.logical(unique_only), is.logical(progress_bar),
      is.logical(quiet),
      is.list(custom_query)
    )

    check_verbose_quiet(verbose, quiet, reverse = FALSE)

    # Check method argument
    check_api_options(method, api_options, TRUE, return_coords)
    check_method(method, reverse = TRUE, mode, reverse_batch_func_map)

    if (length(lat) != length(long)) stop("Lengths of lat and long must be equal.", call. = FALSE)
    lat <- as.numeric(lat)
    long <- as.numeric(long)

    check_common_args("reverse_geo", mode, limit, batch_limit, min_time)

    if (no_query == TRUE) verbose <- TRUE
    start_time <- Sys.time() # start timer

    # Package inputs
    coord_pack <- package_inputs(tibble::tibble(lat = lat, long = long), coords = TRUE)
    num_unique_coords <- nrow(coord_pack$unique)
    if (verbose == TRUE) message(paste0("Number of Unique Coordinates: ", num_unique_coords))

    # filler NA result to return if needed
    NA_value <- tibble::tibble(address = rep(as.character(NA), num_unique_coords))
    names(NA_value)[1] <- address # rename column

    # If no valid coordinates are passed then return NA
    if (num_unique_coords == 1 && all(is.na(coord_pack$unique))) {
      if (verbose == TRUE) message(paste0("No valid coordinates found. Returning NA results."))
      return(unpackage_inputs(coord_pack, NA_value, unique_only, return_coords))
    }

    # Exception for geocoding services that should default to single instead of batch
    if (method %in% pkg.globals$single_first_methods && mode != "batch") {
      mode <- "single"
    }

    # Geocode coordinates one at a time in a loop -------------------------------------------------------
    if ((api_options[["init"]] == TRUE) && (mode != "batch") && ((!(method %in% names(reverse_batch_func_map))) || (num_unique_coords == 1) || (mode == "single"))) {

      # construct arguments for a single address query
      # note that non-lat/long related fields go to the MoreArgs argument of mapply
      # since we aren't iterating through them
      single_coord_args <- c(
        list(FUN = progress_reverse_geo, lat = coord_pack$unique$lat, long = coord_pack$unique$long),
        list(
          MoreArgs = all_args[!names(all_args) %in% c("lat", "long")],
          USE.NAMES = FALSE, SIMPLIFY = FALSE
        )
      )

      if (quiet == FALSE) {
        query_start_message(method, num_unique_coords, reverse = TRUE, batch = FALSE)
      }

      if (progress_bar == TRUE) {
        # intialize progress bar
        pb <- create_progress_bar(
          num_unique_coords
        )
        # add progress bar object to query
        single_coord_args$MoreArgs$pb <- pb
      }

      # Reverse geocode each coordinate individually by recalling this function with mapply
      list_coords <- do.call(mapply, single_coord_args)

      # tell user how long the query took if the progress bar hasn't already
      if (quiet == FALSE && progress_bar == FALSE) {
        query_complete_message(start_time)
      }

      # rbind the list of tibble dataframes together
      stacked_results <- dplyr::bind_rows(list_coords)

      # note that return_inputs has been set to FALSE here since lat/long coordinates will already
      # be returned in the first geo function call (if asked for)
      return(unpackage_inputs(coord_pack, stacked_results, unique_only, FALSE))
    }

    # Batch geocoding --------------------------------------------------------------------------
    if (api_options[["init"]] == TRUE) {
      if (verbose == TRUE) message("Executing batch geocoding...\n")

      # check for conflict between limit and return_coords arguments
      check_limit_for_batch(limit, return_coords, reverse = TRUE)
      flatten_override_warning(flatten, method, reverse = FALSE, batch = TRUE)

      # set batch limit to default if not specified
      if (is.null(batch_limit)) batch_limit <- get_batch_limit(method)
      if (verbose == TRUE) {
        message(paste0(
          "Batch limit: ",
          format(batch_limit, big.mark = ",")
        ))
      }

      # Enforce batch limit if needed
      if (num_unique_coords > batch_limit) {
        stop(paste0(
          format(num_unique_coords, big.mark = ","),
          " unique coordinates found which exceeds the batch limit of ",
          format(batch_limit, big.mark = ","), "."
        ), call. = FALSE)
      }

      # Display message to user on the batch query
      if (quiet == FALSE) {
        query_start_message(
          method,
          num_unique_coords,
          reverse = TRUE,
          batch = TRUE,
          display_time = FALSE
        )
        flatten_override_warning(flatten, method, reverse = FALSE, batch = TRUE)
      }

      # Convert our generic query parameters into parameters specific to our API (method)
      if (no_query == TRUE) {
        return(unpackage_inputs(
          coord_pack, NA_value,
          unique_only, return_coords
        ))
      }

      # call the appropriate function for batch geocoding according the the reverse_batch_func_map named list
      # if batch limit was exceeded then apply that limit
      batch_results <- do.call(
        reverse_batch_func_map[[method]],
        c(
          list(lat = coord_pack$unique$lat, long = coord_pack$unique$long),
          all_args[!names(all_args) %in% c("lat", "long")]
        )
      )

      # if verbose = FALSE, tell user how long batch query took
      if (quiet == FALSE) {
        query_complete_message(start_time)
      }

      # map the raw results back to the original lat,long inputs that were passed if there are duplicates
      return(unpackage_inputs(coord_pack, batch_results, unique_only, return_coords))
    }

    ################################################################################
    #### Code past this point is for reverse geocoding a single coordinate     #####
    ################################################################################

    # Start to build 'generic' query as named list -----------------------------
    generic_query <- list()

    # Create parameters for lat, long coordinates
    custom_query <- get_coord_parameters(
      custom_query,
      method,
      coord_pack$unique$lat,
      coord_pack$unique$long
    )

    # Set API URL (if not already set) ----------------------------------------
    if (is.null(api_url)) {
      api_url <- get_api_url(method,
        reverse = TRUE, geocodio_v = api_options[["geocodio_v"]], iq_region = api_options[["iq_region"]],
        mapbox_permanent = api_options[["mapbox_permanent"]],
        mapquest_open = api_options[["mapquest_open"]], geocodio_hipaa = api_options[["geocodio_hipaa"]]
      )
    }

    ## Workaround for Mapbox/TomTom - The search_text should be in the url
    api_url <- api_url_modification(method, api_url, generic_query, custom_query, reverse = TRUE)

    # Workaround for Bing - The search_text should be in the url
    if (method %in% c("bing")) {
      api_url <- paste0(api_url, custom_query[["to_url"]])
    }
    # Set min_time if not set based on usage limit of service
    if (is.null(min_time)) min_time <- get_min_query_time(method)

    # add limit and api_key to generic query
    generic_query <- add_common_generic_parameters(generic_query, method, no_query, limit)

    # Convert our generic query parameters into parameters specific to our API (method)
    api_query_parameters <- get_api_query(method, generic_query, custom_query)

    # Execute Single Coordinate Query -----------------------------------------
    if (verbose == TRUE) display_query(api_url, api_query_parameters)

    # if no_query = TRUE then return NA results
    if (no_query == TRUE) {
      return(unpackage_inputs(
        coord_pack,
        NA_value,
        unique_only, return_coords
      ))
    }

    query_results <- query_api(api_url, api_query_parameters, method = method)

    if (verbose == TRUE) message(paste0("HTTP Status Code: ", as.character(query_results$status)))

    ## Extract results -----------------------------------------------------------------------------------
    # if there were problems with the results then return NA
    if (query_results$status != 200) {
      extract_errors_from_results(method, query_results$content, verbose)
      results <- NA_value
    } else {
      results <- extract_reverse_results(method, jsonlite::fromJSON(query_results$content), full_results, flatten, limit)
      # rename address column
      names(results)[1] <- address
    }

    # Make sure the proper amount of time has elapsed for the query per min_time
    pause_until(start_time, min_time, debug = verbose)
    if (verbose == TRUE) message() # insert ending line break if verbose

    return(unpackage_inputs(coord_pack, results, unique_only, return_coords))
  }