test_that("super basic", {
  net <- data.frame(id = c(2, 3, 3, 4, 5, 6, 7, 8, 9),
                toid = c(3, 4, 5, 6, 7, 8, 8, 9, 0))

  paths <- navigate_network_dfs(net, 2, direction = "down")

  expect_equal(paths,
               list(list(`1` = c(2, 3, 5, 7, 8, 9),
                         `2` = c(4, 6))))

  path <- navigate_network_dfs(net, 9, direction = "up")

  expect_equal(path,
               list(list(`1` = c(9, 8, 7, 5, 3, 2, 6, 4))))
})

test_that("total div", {
  net <- data.frame(id = c(2, 3, 3, 4, 5, 6, 7, 8, 9, 10),
                  toid = c(3, 4, 5, 6, 7, 8, 9, 10, 0, 0))

  paths <- navigate_network_dfs(net, 2, direction = "down")

  expect_equal(paths,
               list(list(`1` = c(2, 3, 5, 7, 9),
                         `2` = c(4, 6, 8, 10))))

  paths <- navigate_network_dfs(net, c(2, 5), direction = "down")

  expect_equal(paths, list(list(`1` = c(2, 3, 5, 7, 9),
                                `2` = c(4, 6, 8, 10)),
                           list()))

  paths <- navigate_network_dfs(net, c(2, 5), direction = "down", reset = TRUE)

  expect_equal(paths, list(list(`1` = c(2, 3, 5, 7, 9),
                                `2` = c(4, 6, 8, 10)),
                           list(`3` = c(5, 7, 9))))

  paths <- navigate_network_dfs(net, c(9, 10), direction = "up")

  expect_equal(paths,
               list(list(`1` = c(9, 7, 5, 3, 2)),
                    list(`1` = c(10, 8, 6, 4))))

})

test_that("real data", {
  x <- sf::read_sf(system.file("extdata/new_hope.gpkg", package = "hydroloom"))
  g <- hy(x)

  g <- add_toids(g, return_dendritic = FALSE)

  g <- dplyr::select(sf::st_drop_geometry(g), id, toid)

  gg <- make_index_ids(g)

  paths <- navigate_network_dfs(g, 8893402, direction = "down")

  paths2 <- navigate_network_dfs(gg, 8893402, direction = "down")

  expect_identical(paths, paths2)

  expect_equal(length(paths), 1)

  expect_equal(length(paths[[1]]), 7)

  expect_equal(length(paths[[1]][[1]]), 20)

  # the tail of diverted paths point to the path they rejoin
  expect_true(g$toid[g$id == paths[[1]][[2]][2]] %in% paths[[1]][[1]])

  paths <- navigate_network_dfs(g, starts = 8891152)

  expect_equal(length(paths[[1]]), 46)

  expect_error(navigate_network_dfs(g, 12345))

  expect_error(navigate_network_dfs(gg, 12345),
               "all starts must be in x")

  expect_error(navigate_network_dfs(gg, 8891152, direction = "up"),
               "'down' if x contains to index ids")

  ggg <- make_fromids(gg, return_list = FALSE)

  expect_error(navigate_network_dfs(ggg, 8891152, direction = "down"),
               "make_index_ids or make_fromids")

  ggg <- make_fromids(gg, return_list = TRUE)

  paths <- navigate_network_dfs(g, 8897784, direction = "up")

  paths2 <- navigate_network_dfs(ggg, 8897784, direction = "up")

  expect_identical(paths, paths2)

  expect_equal(length(paths[[1]]), 83)

  path <- paths[[1]][[which(sapply(paths[[1]], function(x) 8891126 %in% x))]]

  expect_true(8895394 %in% path)

  x <- sf::read_sf(system.file("extdata/new_hope.gpkg", package = "hydroloom"))
  g <- hy(x)

  g <- add_toids(g, return_dendritic = TRUE)

  g <- dplyr::select(sf::st_drop_geometry(g), id, toid)

  paths <- navigate_network_dfs(g, 8893402, direction = "down")

  expect_equal(length(paths[[1]][[1]]), 21)

  paths <- navigate_network_dfs(g, 8897784, direction = "up")

  expect_equal(length(paths[[1]]), 1)
})