library(testthat)
library(AutoEDA)
library(ggplot2)

#==========================================================
# cluster_analysis()
#==========================================================

test_that("cluster_analysis returns ClusterResult", {

  cl <- cluster_analysis(iris)

  expect_s3_class(cl, "ClusterResult")

})

test_that("cluster_analysis accepts valid data.frame", {

  expect_no_error(
    cluster_analysis(iris)
  )

})

test_that("cluster_analysis returns requested number of clusters", {

  cl <- cluster_analysis(
    iris,
    centers = 3
  )

  expect_equal(
    length(unique(cl$cluster)),
    3
  )

})

test_that("cluster_analysis stores original data", {

  cl <- cluster_analysis(iris)

  expect_true(!is.null(cl$data))

})

#==========================================================
# cluster_plot()
#==========================================================

test_that("cluster_plot returns ggplot", {

  cl <- cluster_analysis(iris)

  p <- cluster_plot(cl)

  expect_s3_class(
    p,
    "ggplot"
  )

})

#==========================================================
# cluster_dendrogram()
#==========================================================

test_that("cluster_dendrogram returns hclust invisibly", {

  hc <- cluster_dendrogram(iris)

  expect_s3_class(
    hc,
    "hclust"
  )

})

#==========================================================
# cluster_elbow()
#==========================================================

test_that("cluster_elbow returns ggplot", {

  p <- cluster_elbow(iris)

  expect_s3_class(
    p,
    "ggplot"
  )

})

#==========================================================
# cluster_silhouette()
#==========================================================

test_that("cluster_silhouette returns ggplot", {

  p <- cluster_silhouette(iris)

  expect_s3_class(
    p,
    "ggplot"
  )

})

#==========================================================
# Invalid cluster_analysis()
#==========================================================

test_that("cluster_analysis rejects non-data.frame", {

  expect_error(
    cluster_analysis(1:10)
  )

})

test_that("cluster_analysis rejects empty data.frame", {

  expect_error(
    cluster_analysis(data.frame())
  )

})

test_that("cluster_analysis rejects one numeric variable", {

  expect_error(
    cluster_analysis(
      data.frame(x = 1:10)
    )
  )

})

test_that("cluster_analysis rejects invalid centers", {

  expect_error(
    cluster_analysis(
      iris,
      centers = 1
    )
  )

})

test_that("cluster_analysis rejects invalid nstart", {

  expect_error(
    cluster_analysis(
      iris,
      nstart = 0
    )
  )

})

#==========================================================
# Invalid cluster_plot()
#==========================================================

test_that("cluster_plot rejects invalid object", {

  expect_error(
    cluster_plot(iris)
  )

})

#==========================================================
# Invalid cluster_dendrogram()
#==========================================================

test_that("cluster_dendrogram rejects invalid input", {

  expect_error(
    cluster_dendrogram(1:10)
  )

})

#==========================================================
# Invalid cluster_elbow()
#==========================================================

test_that("cluster_elbow rejects invalid input", {

  expect_error(
    cluster_elbow(1:10)
  )

})

#==========================================================
# Invalid cluster_silhouette()
#==========================================================

test_that("cluster_silhouette rejects invalid input", {

  expect_error(
    cluster_silhouette(1:10)
  )

})

#==========================================================
# Additional validation tests
#==========================================================

test_that("cluster_dendrogram rejects empty data.frame", {

  expect_error(
    cluster_dendrogram(data.frame())
  )

})

test_that("cluster_elbow rejects empty data.frame", {

  expect_error(
    cluster_elbow(data.frame())
  )

})

test_that("cluster_silhouette rejects empty data.frame", {

  expect_error(
    cluster_silhouette(data.frame())
  )

})

test_that("cluster_analysis rejects non-numeric data", {

  expect_error(
    cluster_analysis(
      data.frame(
        A = letters[1:10],
        B = LETTERS[1:10]
      )
    )
  )

})

test_that("cluster_dendrogram rejects non-numeric data", {

  expect_error(
    cluster_dendrogram(
      data.frame(
        A = letters[1:10],
        B = LETTERS[1:10]
      )
    )
  )

})

test_that("cluster_elbow rejects non-numeric data", {

  expect_error(
    cluster_elbow(
      data.frame(
        A = letters[1:10],
        B = LETTERS[1:10]
      )
    )
  )

})

test_that("cluster_silhouette rejects non-numeric data", {

  expect_error(
    cluster_silhouette(
      data.frame(
        A = letters[1:10],
        B = LETTERS[1:10]
      )
    )
  )

})

test_that("cluster_analysis rejects invalid scale argument", {

  expect_error(
    cluster_analysis(
      iris,
      scale = "yes"
    )
  )

})

test_that("cluster_analysis rejects invalid nstart type", {

  expect_error(
    cluster_analysis(
      iris,
      nstart = "25"
    )
  )

})

test_that("cluster_analysis rejects invalid centers type", {

  expect_error(
    cluster_analysis(
      iris,
      centers = "3"
    )
  )

})

test_that("cluster_elbow returns ggplot", {

  p <- cluster_elbow(iris)

  expect_s3_class(p, "ggplot")
  expect_false(is.null(p))

})

test_that("cluster_silhouette returns ggplot", {

  p <- cluster_silhouette(iris)

  expect_s3_class(p, "ggplot")
  expect_false(is.null(p))

})

test_that("cluster_plot returns ggplot", {

  cl <- cluster_analysis(iris)

  p <- cluster_plot(cl)

  expect_s3_class(p, "ggplot")
  expect_false(is.null(p))

})

test_that("cluster_dendrogram returns hclust", {

  hc <- cluster_dendrogram(iris)

  expect_s3_class(hc, "hclust")
  expect_false(is.null(hc))

})