context("test-search_neighbors")

test_that("search_neighbors works", {
  nirdata <- data("NIRsoil", package = "prospectr")

  Xu <- NIRsoil$spc[!as.logical(NIRsoil$train), ]
  Yu <- NIRsoil$CEC[!as.logical(NIRsoil$train)]

  Yr <- NIRsoil$CEC[as.logical(NIRsoil$train)]
  Xr <- NIRsoil$spc[as.logical(NIRsoil$train), ]

  Xu <- Xu[!is.na(Yu), ]
  Xr <- Xr[!is.na(Yr), ]

  Yu <- Yu[!is.na(Yu)]
  Yr <- Yr[!is.na(Yr)]

  spikes <- c(5, 10, 15)

  nn <- search_neighbors(
    Xr = Xr, Xu = Xu,
    diss_method = c("pca.nipals"),
    Yr = Yr, k = 50,
    spike = spikes,
    pc_selection = list("manual", 10),
    center = TRUE, scale = FALSE
  )

  nn_k_diss <- search_neighbors(
    Xr = Xr, Xu = Xu,
    diss_method = c("pca.nipals"),
    Yr = Yr, k_diss = 0.1, k_range = c(10, 50),
    spike = spikes,
    pc_selection = list("manual", 10),
    center = TRUE, scale = FALSE
  )

  first_nns_pca <- search_neighbors(
    Xr = Xr, Xu = Xu,
    diss_method = c("pca"),
    Yr = Yr, k = 10,
    pc_selection = list("manual", 10),
    center = TRUE, scale = FALSE
  )
  expected_sum_of_indices_pca <- 17853

  first_nns_pls <- search_neighbors(
    Xr = Xr, Xu = Xu,
    diss_method = c("pls"),
    Yr = Yr, k = 10,
    pc_selection = list("manual", 10),
    center = TRUE, scale = FALSE
  )
  expected_sum_of_indices_pls <- 18410

  first_nns_cor <- search_neighbors(
    Xr = Xr, Xu = Xu,
    diss_method = c("cor"),
    Yr = Yr, k_diss = 0.1, k_range = c(10, 50),
    pc_selection = list("manual", 10),
    center = TRUE, scale = FALSE
  )
  expected_sum_of_indices_cor <- 18036


  first_nns_euclid <- search_neighbors(
    Xr = Xr, Xu = Xu,
    diss_method = c("euclid"),
    Yr = Yr, k_diss = 0.1, k_range = c(10, 50),
    pc_selection = list("manual", 10),
    center = TRUE, scale = FALSE
  )
  expected_sum_of_indices_euclid <- 19586

  first_nns_cosine <- search_neighbors(
    Xr = Xr, Xu = Xu,
    diss_method = c("cosine"),
    Yr = Yr, k_diss = 0.1, k_range = c(10, 50),
    pc_selection = list("manual", 10),
    center = TRUE, scale = FALSE
  )
  expected_sum_of_indices_cosine <- 18910

  expect_is(nn, "list")
  expect_is(nn_k_diss, "list")
  expect_true(all(rowMeans(nn$neighbors[1:length(spikes), ]) == spikes))
  expect_true(all(rowMeans(nn_k_diss$neighbors[1:length(spikes), ]) == spikes))
  expect_true(sum(first_nns_pca$neighbors[1, ]) == expected_sum_of_indices_pca)
  expect_true(sum(first_nns_pls$neighbors[1, ]) == expected_sum_of_indices_pls)
  expect_true(sum(first_nns_cor$neighbors[1, ]) == expected_sum_of_indices_cor)
  expect_true(sum(first_nns_euclid$neighbors[1, ]) == expected_sum_of_indices_euclid)
  expect_true(sum(first_nns_cosine$neighbors[1, ]) == expected_sum_of_indices_cosine)
})