draw <- function(expr) {
  grDevices::pdf(NULL)
  on.exit(grDevices::dev.off())
  force(expr)
}

test_that("means are drawn at their values with the right error bars and letters", {
  f <- design_anova(maize_nitrogen, "Yield_t_ha", "Nitrogen_kg_ha", block = "Block")
  cmp <- compare_means(f, "Nitrogen_kg_ha")
  r <- draw(plot(cmp))
  expect_equal(r$mean, cmp$means$mean)
  expect_equal(r$upper - r$mean, cmp$means$se)
  expect_equal(r$letters, cmp$means$group)
  expect_true(all(r$letter_y > r$upper))
  r <- draw(plot(cmp, style = "points", error = "ci"))
  expect_equal(r$upper - r$mean, stats::qt(0.975, f$residual[["df"]]) * cmp$means$se)
  r <- draw(plot(cmp, style = "box"))
  expect_true(all(r$letter_y > tapply(maize_nitrogen$Yield_t_ha, maize_nitrogen$Nitrogen_kg_ha, max)))
  r <- draw(plot(cmp, sort = TRUE, error = "none"))
  expect_equal(r$mean, sort(cmp$means$mean, decreasing = TRUE))
  expect_equal(r$upper, r$mean)
})

test_that("every figure draws without errors and restores the graphical parameters", {
  mar0 <- graphics::par("mar")
  f <- design_anova(tomato_factorial, "Yield_kg_plant", c("Variety", "Fertilizer"), block = "Block")
  mz <- design_anova(maize_nitrogen, "Yield_t_ha", "Nitrogen_kg_ha", block = "Block")
  sp <- design_anova(split_irrigation, "Yield_t_ha", c("Irrigation", "Variety"), block = "Block", design = "split_rcbd")
  lt <- design_anova(wheat_latin, "Yield_t_ha", "Treatment", row = "Row", col = "Column")
  dz <- design_anova(disease_scores, "Severity_score", "Fungicide", block = "Block")
  expect_silent(draw(plot(mz)))
  expect_silent(draw(plot(mz, which = 2)))
  expect_silent(draw(plot(transformations(f))))
  expect_silent(draw(plot(trend(mz, "Nitrogen_kg_ha"))))
  expect_silent(draw(plot_interaction(f, "Fertilizer", "Variety")))
  expect_silent(draw(plot_cell_means(f, "Variety", "Fertilizer")))
  expect_silent(draw(plot(compare_means(sp, "Variety", by = "Irrigation"))))
  expect_silent(draw(plot_differences(compare_means(sp, "Irrigation", by = "Variety"))))
  expect_silent(draw(plot(nonparametric(dz))))
  expect_silent(draw(plot_field(lt, value = "residuals")))
  r <- draw(plot_ss_partition(sp))
  expect_equal(sum(r$pct), 100)
  expect_equal(graphics::par("mar"), mar0)
})

test_that("the field map needs the field coordinates", {
  f <- design_anova(maize_nitrogen, "Yield_t_ha", "Nitrogen_kg_ha", block = "Block")
  expect_error(draw(plot_field(f)), "row")
  d <- maize_nitrogen; d$FieldRow <- d$Block; d$FieldCol <- rep(1:4, 4)
  f <- design_anova(d, "Yield_t_ha", "Nitrogen_kg_ha", block = "Block")
  expect_error(draw(plot_field(f, row = "FieldRow", col = "FieldCol")), "pass 'data'")
  r <- draw(plot_field(f, row = "FieldRow", col = "FieldCol", data = d))
  expect_equal(nrow(unique(r[c("row", "col")])), 16)
})

test_that("without a working cairo device (macOS without XQuartz) figures and reports still work", {
  env <- AgriDesign:::.dev_env
  old <- env$cairo
  on.exit(assign("cairo", old, envir = env))
  AgriDesign:::.cairo_ok()
  assign("cairo", FALSE, envir = env)
  f <- design_anova(maize_nitrogen, "Yield_t_ha", "Nitrogen_kg_ha", block = "Block")
  n0 <- length(grDevices::dev.list())
  png <- tempfile(fileext = ".png")
  save_figure(png, plot(f), width = 8, height = 6, res = 300)
  b <- readBin(png, "raw", file.size(png)); i <- grepRaw("pHYs", b)
  expect_equal(round(sum(as.integer(b[(i + 4):(i + 7)]) * 256^(3:0)) * 0.0254), 300)
  h <- design_report(f, assumptions = FALSE, pairwise = FALSE)
  expect_gte(attr(h, "figures"), 2)
  expect_true(grepl("data:image/png;base64", h, fixed = TRUE))
  expect_error(save_figure(tempfile(fileext = ".svg"), plot(f)), "cairo")
  expect_equal(length(grDevices::dev.list()), n0)
})

test_that("the PNG resolution chunk is written with a valid CRC", {
  expect_equal(AgriDesign:::.crc32(charToRaw("123456789")), 3421780262)
  expect_equal(AgriDesign:::.crc32(charToRaw("IEND")), 2923585666)
})

test_that("save_figure writes raster files with their resolution and closes the device", {
  f <- design_anova(maize_nitrogen, "Yield_t_ha", "Nitrogen_kg_ha", block = "Block")
  n0 <- length(grDevices::dev.list())
  png <- tempfile(fileext = ".png")
  save_figure(png, plot(compare_means(f, "Nitrogen_kg_ha")), width = 8, height = 6, res = 300)
  b <- readBin(png, "raw", file.size(png)); i <- grepRaw("pHYs", b)
  ppm <- sum(as.integer(b[(i + 4):(i + 7)]) * 256^(3:0))
  expect_equal(round(ppm * 0.0254), 300)
  pdf <- tempfile(fileext = ".pdf")
  save_figure(pdf, plot(f), width = 20, height = 14)
  expect_true(file.size(pdf) > 1000)
  expect_equal(length(grDevices::dev.list()), n0)
  expect_error(save_figure(tempfile(fileext = ".bmp"), plot(f)), "unknown format")
  expect_equal(length(grDevices::dev.list()), n0)
  expect_equal(agri_colors(3), c("#2f7d4f", "#c8842a", "#2b7bb9"))
})