skip_if_not_installed("splines")

m1 <- lm(Sepal.Length ~ splines::bs(Petal.Width, df = 4) + Species, data = iris)

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

test_that("find_predictors", {
  expect_identical(find_predictors(m1), list(conditional = c("Petal.Width", "Species")))
  expect_identical(
    find_predictors(m1, flatten = TRUE),
    c("Petal.Width", "Species")
  )
  expect_null(find_predictors(m1, effects = "random"))
})

test_that("get_predictors", {
  expect_equal(get_predictors(m1), iris[, c("Petal.Width", "Species")])
})

test_that("find_response", {
  expect_identical(find_response(m1), "Sepal.Length")
})

test_that("get_response", {
  expect_identical(get_response(m1), iris$Sepal.Length)
})

test_that("link_inverse", {
  expect_equal(link_inverse(m1)(0.2), 0.2, tolerance = 1e-4)
})

test_that("link_function", {
  expect_equal(link_function(m1)(0.2), 0.2, tolerance = 1e-4)
})

test_that("get_data", {
  expect_equal(nrow(get_data(m1)), 150)
  expect_equal(
    colnames(get_data(m1)),
    c("Sepal.Length", "Petal.Width", "Species")
  )
})

test_that("find_formula", {
  expect_length(find_formula(m1), 1)
  expect_equal(
    find_formula(m1),
    list(
      conditional = as.formula("Sepal.Length ~ splines::bs(Petal.Width, df = 4) + Species")
    ),
    ignore_attr = TRUE
  )
})

test_that("find_variables", {
  expect_equal(
    find_variables(m1),
    list(
      response = "Sepal.Length",
      conditional = c("Petal.Width", "Species")
    )
  )
  expect_equal(
    find_variables(m1, flatten = TRUE),
    c("Sepal.Length", "Petal.Width", "Species")
  )
})

test_that("find_parameters", {
  expect_equal(
    find_parameters(m1),
    list(
      conditional = c(
        "(Intercept)",
        "splines::bs(Petal.Width, df = 4)1",
        "splines::bs(Petal.Width, df = 4)2",
        "splines::bs(Petal.Width, df = 4)3",
        "splines::bs(Petal.Width, df = 4)4",
        "Speciesversicolor",
        "Speciesvirginica"
      )
    )
  )
})

test_that("get_parameters", {
  expect_equal(nrow(get_parameters(m1)), 7)
  expect_equal(
    get_parameters(m1)$Parameter,
    c(
      "(Intercept)",
      "splines::bs(Petal.Width, df = 4)1",
      "splines::bs(Petal.Width, df = 4)2",
      "splines::bs(Petal.Width, df = 4)3",
      "splines::bs(Petal.Width, df = 4)4",
      "Speciesversicolor",
      "Speciesvirginica"
    )
  )
})

test_that("find_algorithm", {
  expect_equal(find_algorithm(m1), list(algorithm = "OLS"))
})

test_that("find_terms", {
  expect_equal(
    find_terms(m1),
    list(
      response = "Sepal.Length",
      conditional = c("splines", "bs(Petal.Width, df = 4)", "Species")
    )
  )
})

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