test_that("fwise summaries work for tfd_reg", {
  x <- tf_rgp(3, arg = seq(0, 5, length.out = 101))
  # use non-unit length to verify scaling
  x_clamp <- (x - tf_fmin(x)) / (tf_fmax(x) - tf_fmin(x))
  expect_equal(tf_fmin(x_clamp), c(0, 0, 0), ignore_attr = TRUE)
  expect_equal(tf_fmax(x_clamp), c(1, 1, 1), ignore_attr = TRUE)

  x_std <- (x - tf_fmean(x)) / tf_fsd(x)
  expect_equal(tf_fmean(x_std), c(0, 0, 0), ignore_attr = TRUE)
  expect_equal(tf_fsd(x_std), c(1, 1, 1), ignore_attr = TRUE)

  expect_equal(tf_crosscov(x, x), tf_fvar(x))
  expect_equal(tf_crosscor(x, -x), c(-1, -1, -1), ignore_attr = TRUE)
})

test_that("fwise summaries work for tfd_irreg", {
  set.seed(1221)
  x <- tf_rgp(3, arg = 201L) |>
    tf_jiggle() |>
    tfd(evaluator = tf_approx_fill_extend)

  x_clamp <- (x - tf_fmin(x)) / (tf_fmax(x) - tf_fmin(x))
  expect_equal(tf_fmin(x_clamp), c(0, 0, 0), ignore_attr = TRUE)
  expect_equal(tf_fmax(x_clamp), c(1, 1, 1), ignore_attr = TRUE)

  x_std <- (x - tf_fmean(x)) / tf_fsd(x)
  expect_equal(
    tf_fmean(x_std),
    c(0, 0, 0),
    ignore_attr = TRUE,
    tolerance = 0.01
  )
  expect_equal(tf_fsd(x_std), c(1, 1, 1), ignore_attr = TRUE, tolerance = 0.01)

  expect_equal(tf_crosscov(x, x), tf_fvar(x))
  expect_equal(tf_crosscor(x, -x), c(-1, -1, -1), ignore_attr = TRUE)
})

test_that("fwise summaries work for tfb_spline", {
  suppressMessages(x <- tf_rgp(3) |> tfb(k = 35))

  x_clamp <- ((x - tf_fmin(x)) / (tf_fmax(x) - tf_fmin(x))) |>
    suppressWarnings()
  expect_equal(
    tf_fmin(x_clamp),
    c(0, 0, 0),
    ignore_attr = TRUE,
    tolerance = 0.001
  )
  expect_equal(tf_fmax(x_clamp), c(1, 1, 1), ignore_attr = TRUE)

  x_std <- ((x - tf_fmean(x)) / tf_fsd(x)) |> suppressWarnings()
  expect_equal(tf_fmean(x_std), c(0, 0, 0), ignore_attr = TRUE)
  expect_equal(
    tf_fsd(x_std) |> suppressWarnings(),
    c(1, 1, 1),
    ignore_attr = TRUE
  )

  expect_equal(tf_crosscov(x, x), tf_fvar(x))
})

test_that("fwise summaries work for tfb_fpc", {
  set.seed(1212)
  x <- (tf_rgp(20, arg = 501L) |> tfb_fpc(k = 10, pve = 0.999))[1:3]

  x_clamp <- ((x - tf_fmin(x)) / (tf_fmax(x) - tf_fmin(x))) |>
    suppressWarnings()
  expect_equal(
    tf_fmin(x_clamp),
    c(0, 0, 0),
    ignore_attr = TRUE,
    tolerance = 0.05
  ) #!! uh oh
  expect_equal(
    tf_fmax(x_clamp),
    c(1, 1, 1),
    ignore_attr = TRUE,
    tolerance = 0.05
  ) #!! uh oh

  x_std <- ((x - tf_fmean(x)) / tf_fsd(x)) |> suppressWarnings()
  expect_equal(
    tf_fmean(x_std),
    c(0, 0, 0),
    ignore_attr = TRUE,
    tolerance = 0.05
  ) #!! uh oh
  expect_equal(tf_fsd(x_std), c(1, 1, 1), ignore_attr = TRUE, tolerance = 0.05) #!! uh oh

  expect_equal(tf_crosscov(x, x), tf_fvar(x))
})