o <- strat_kmeans(mraster = mraster, nStrata = 4, iter = 100, details = TRUE)

odf <- terra::values(o$raster, dataframe = TRUE)

odfna <- odf[complete.cases(odf), ]

test_that("errors", {
  expect_error(strat_kmeans(mraster = "mraster", nStrata = 4, iter = 100, details = TRUE), "'mraster' must be type SpatRaster.")
  expect_error(strat_kmeans(mraster = mraster, nStrata = "4", iter = 100, details = TRUE), "'nStrata' must be type numeric.")
  expect_error(strat_kmeans(mraster = mraster, nStrata = 4, iter = "100", details = TRUE), "'iter' must be type numeric.")
  expect_error(strat_kmeans(mraster = mraster, nStrata = 4, iter = 100, algorithm = 4), "'algorithm' must be type character.")
  expect_error(strat_kmeans(mraster = mraster, nStrata = 4, iter = 100, center = "TRUE"), "'center' must be type logical.")
  expect_error(strat_kmeans(mraster = mraster, nStrata = 4, iter = 100, scale = "TRUE"), "'scale' must be type logical.")
  expect_error(strat_kmeans(mraster = mraster, nStrata = 4, iter = 100, plot = "TRUE"), "'plot' must be type logical.")
  expect_error(strat_kmeans(mraster = mraster, nStrata = 4, iter = 100, details = "TRUE"), "'details' must be type logical.")
})

test_that("Total outputs", {
  expect_message(strat_kmeans(mraster = mraster, nStrata = 4, iter = 100, plot = TRUE), "K-means being performed on 3 layers with 4 centers.")
  expect_equal(length(o$details$cluster), 91195L)
  expect_equal(length(o$details$centers), 12L)
  expect_equal(ncol(o$raster), 373L)
  expect_equal(length(odfna), 91195L)
  expect_equal(length(unique(odfna)), 4L)
})

test_that("Out classes", {
  expect_s4_class(o$raster, "SpatRaster")
  expect_s3_class(o$details, "kmeans")
  expect_equal(c(1, 2, 3, 4), sort(unique(odfna)))
})