skip_if_not_installed("ordinal")
skip_if_not_installed("MASS")

data(housing, package = "MASS")
m1 <- ordinal::clm2(Sat ~ Infl + Type + Cont, weights = Freq, data = housing)

test_that("model_info", {
  expect_true(model_info(m1)$is_ordinal)
  expect_false(model_info(m1)$is_multinomial)
  expect_false(model_info(m1)$is_linear)
})

test_that("find_predictors", {
  expect_identical(find_predictors(m1), list(conditional = c("Infl", "Type", "Cont")))
  expect_identical(
    find_predictors(m1, flatten = TRUE),
    c("Infl", "Type", "Cont")
  )
  expect_null(find_predictors(m1, effects = "random"))
})

test_that("find_random", {
  expect_null(find_random(m1))
})

test_that("get_random", {
  expect_warning(get_random(m1))
})

test_that("find_response", {
  expect_identical(find_response(m1), "Sat")
})

test_that("get_response", {
  expect_equal(get_response(m1), housing$Sat)
})

test_that("get_predictors", {
  expect_equal(colnames(get_predictors(m1)), c("Infl", "Type", "Cont"))
})

test_that("link_inverse", {
  expect_equal(link_inverse(m1)(0.2), plogis(0.2), tolerance = 1e-5)
})

test_that("find_weights", {
  expect_equal(find_weights(m1), "Freq")
})

test_that("get_weights", {
  expect_equal(get_weights(m1), housing$Freq)
})

test_that("get_data", {
  expect_equal(nrow(get_data(m1)), 72)
  expect_equal(
    colnames(get_data(m1)),
    c("Sat", "Infl", "Type", "Cont", "Freq")
  )
})

test_that("find_formula", {
  expect_length(find_formula(m1), 1)
  expect_equal(
    find_formula(m1),
    list(conditional = as.formula("Sat ~ Infl + Type + Cont")),
    ignore_attr = TRUE
  )
})

test_that("find_terms", {
  expect_equal(find_terms(m1), list(
    response = "Sat",
    conditional = c("Infl", "Type", "Cont")
  ))
  expect_equal(
    find_terms(m1, flatten = TRUE),
    c("Sat", "Infl", "Type", "Cont")
  )
})

test_that("n_obs", {
  expect_equal(n_obs(m1), 1681)
})

test_that("linkfun", {
  expect_false(is.null(link_function(m1)))
})

test_that("linkinv", {
  expect_false(is.null(link_inverse(m1)))
})

test_that("find_parameters", {
  expect_equal(
    find_parameters(m1),
    list(
      conditional = c(
        "Low|Medium",
        "Medium|High",
        "InflMedium",
        "InflHigh",
        "TypeApartment",
        "TypeAtrium",
        "TypeTerrace",
        "ContHigh"
      )
    )
  )
  expect_equal(nrow(get_parameters(m1)), 8)
  expect_equal(
    get_parameters(m1)$Parameter,
    c(
      "Low|Medium",
      "Medium|High",
      "InflMedium",
      "InflHigh",
      "TypeApartment",
      "TypeAtrium",
      "TypeTerrace",
      "ContHigh"
    )
  )
})

test_that("is_multivariate", {
  expect_false(is_multivariate(m1))
})

test_that("find_statistic", {
  expect_identical(find_statistic(m1), "z-statistic")
})