data_dir <- file.path("..", "testdata")
tempfile_nc <- function() {
  tempfile_helper("seasvar_")
}

########## test data ##########
file_out <- tempfile_nc()

seasvar("SIS",
       file.path(data_dir, "ex_mon2.nc"),
       file_out)
file <- nc_open(file_out)

test_that("data is correct", {
  actual <- ncvar_get(file, "SIS")
  expected_data <- c(508.33334,508.33334,508.33334,508.33334,508.33334,
                     508.33334,508.33334,508.33334,508.33334,508.33334,
                     508.33334,508.33334,508.33334,508.33334,508.33334,
                     508.33334,508.33334,508.33334,508.33334,508.33334,
                     625.0,625.0,625.0,625.0,625.0,
                     
                     508.33334,508.33334,508.33334,508.33334,508.33334,
                     508.33334,508.33334,508.33334,508.33334,508.33334,
                     508.33334,508.33334,508.33334,508.33334,508.33334,
                     625.0,625.0,625.0,625.0,625.0,
                     625.0,625.0,625.0,625.0,625.0,
                     
                     508.33334,508.33334,508.33334,508.33334,508.33334,
                     508.33334,508.33334,508.33334,508.33334,508.33334,
                     625.0,625.0,625.0,625.0,625.0,
                     625.0,625.0,625.0,625.0,625.0,
                     625.0,625.0,625.0,625.0,625.0)
  expected <- array(expected_data, dim = c(5, 5, 3))
  
  expect_equivalent(actual[1:75], expected, tolerance = 1e-4)
  
})

########## test attributes ##########
test_that("variable attributes are correct", {
  actual <- ncatt_get(file, "SIS", "units")$value
  expect_equal(actual, "W m-2")
  
  actual <- ncatt_get(file, "SIS", "_FillValue")$value
  expect_equal(actual, -999)
  
  actual <- ncatt_get(file, "SIS", "standard_name")$value
  expect_equal(actual, "SIS_standard")
  
  actual <- ncatt_get(file, "SIS", "long_name")$value
  expect_equal(actual, "Surface Incoming Shortwave Radiation")
  
  actual <- ncatt_get(file, "SIS", "missing_value")$value
  expect_equal(actual, 0)
})

test_that("attributes are correct", {
  actual <- ncatt_get(file, "lon", "units")$value
  expect_equal(actual, "degrees_east")
  
  actual <- ncatt_get(file, "lon", "long_name")$value
  expect_equal(actual, "longitude")
  
  actual <- ncatt_get(file, "lon", "standard_name")$value
  expect_equal(actual, "longitude")
  
  actual <- ncatt_get(file, "lon", "axis")$value
  expect_equal(actual, "X")
  
  actual <- ncatt_get(file, "lat", "units")$value
  expect_equal(actual, "degrees_north")
  
  actual <- ncatt_get(file, "lat", "long_name")$value
  expect_equal(actual, "latitude")
  
  actual <- ncatt_get(file, "lat", "standard_name")$value
  expect_equal(actual, "latitude")
  
  actual <- ncatt_get(file, "lat", "axis")$value
  expect_equal(actual, "Y")
  
  actual <- ncatt_get(file, "time", "units")$value
  expect_equal(actual, "hours since 1983-01-01 00:00:00")
  
  actual <- ncatt_get(file, "time", "long_name")$value
  expect_equal(actual, "time")
  
  actual <- ncatt_get(file, "time", "standard_name")$value
  expect_equal(actual, "time")
  
  actual <- ncatt_get(file, "time", "calendar")$value
  expect_equal(actual, "standard")
  
  actual <- ncatt_get(file, "SIS", "standard_name")$value
  expect_equal(actual, "SIS_standard")
  
  actual <- ncatt_get(file, "SIS", "long_name")$value
  expect_equal(actual, "Surface Incoming Shortwave Radiation")
  
  actual <- ncatt_get(file, "SIS", "units")$value
  expect_equal(actual, "W m-2")
  
  actual <- ncatt_get(file, "SIS", "_FillValue")$value
  expect_equal(actual, -999)
  
  actual <- ncatt_get(file, "SIS", "cmsaf_info")$value
  expect_equal(actual, "cmsafops::seasvar for variable SIS")
  
  global_attr <- ncatt_get(file, 0)
  expect_equal(length(global_attr), 1)
  
  actual <- names(global_attr[1])
  expect_equal(actual, "Info")
  
  actual <- global_attr[[1]]
  expect_equal(actual, "Created with the CM SAF R Toolbox.")
})

test_that("coordinates are correct", {
  actual <- ncvar_get(file, "lon")
  expect_identical(actual, array(seq(5, 7, 0.5)))
  
  actual <- ncvar_get(file, "lat")
  expect_identical(actual, array(seq(45, 47, 0.5)))
  
  actual <- ncvar_get(file, "time")
  expect_equal(actual[1:3], array(c(150456, 152664, 154872)))
})

nc_close(file)