test_that("rowapply/rownumber basics", {
  df <- data.frame(a = 1:3, b = 4:6)
  expect_equal(rowapply(df, fun = sum), c(5, 7, 9))
  expect_equal(rownumber(c("a", "b", "c")), 1:3)
})

test_that("column metadata helpers", {
  df <- data.frame(a = 1:3, b = c("x", "x", "y"), stringsAsFactors = FALSE)

  expect_equal(colnames(df), c("a", "b"))
  expect_equal(classes(df)$class, c("integer", "character"))
  expect_equal(unname(uniques(df)), c(3L, 2L))
  expect_equal(unname(cardinality(df, "b")), 2)
  expect_equal(unname(cardinality(df, "b", prop = TRUE)), 2 / 3)
  expect_equal(constants(data.frame(a = 1, b = 1:2)), "a")
  expect_equal(emptycols(data.frame(a = c(NA, NA), b = 1:2)), "a")
  expect_equal(emptycols(data.frame(a = c("", "  "), b = c("x", "y"), stringsAsFactors = FALSE)), "a")
})

test_that("row-level dedup/blank helpers", {
  df <- data.frame(a = c(1, 1, 2), b = c("x", "x", "y"), stringsAsFactors = FALSE)
  expect_equal(nrow(duplicaterows(df)), 2L)

  expect_equal(duplicatekeys(df, "a")$a, 1)
  expect_equal(duplicatenames(data.frame(a = 1, a = 2, check.names = FALSE)), "a")
})

test_that("commonnames finds shared column names", {
  expect_equal(commonnames(data.frame(a = 1, b = 2), data.frame(b = 1, c = 2)), "b")
})

test_that("name-cleaning helpers", {
  df <- data.frame(`a b` = 1, check.names = FALSE)
  expect_equal(names(cleannames(df)), "a_b")
  expect_equal(names(repairnames(df, method = "unique")), "a_b")

  df2 <- data.frame(a = 1, b = 2)
  expect_equal(names(renamewith(df2, "a", toupper)), c("A", "b"))
})

test_that("move/firstcols/lastcols reorder columns", {
  df <- data.frame(a = 1, b = 2, c = 3)

  expect_equal(names(move(df, "c")), c("c", "a", "b"))
  expect_equal(names(move(df, "a", after = "c")), c("b", "c", "a"))
  expect_equal(names(firstcols(df, "c")), c("c", "a", "b"))
  expect_equal(names(lastcols(df, "a")), c("b", "c", "a"))
})

test_that("firstrows/lastrows/samplerows/samplefrac/reverse/orderrows", {
  df <- data.frame(x = 1:5)

  expect_equal(firstrows(df, 2)$x, c(1, 2))
  expect_equal(lastrows(df, 2)$x, c(4, 5))
  expect_equal(nrow(samplerows(df, 3)), 3L)
  expect_equal(nrow(samplefrac(df, 0.4)), 2L)
  expect_equal(reverse(df)$x, rev(df$x))
  expect_equal(orderrows(df, "x", decreasing = TRUE)$x, rev(df$x))
})

test_that("samplerows/samplefrac with by sample within each group", {
  set.seed(1)
  d <- data.frame(g = rep(letters[1:3], c(4, 8, 12)), x = 1:24)

  s <- samplerows(d, 2, by = "g")
  expect_equal(as.integer(table(s$g)), c(2L, 2L, 2L))
  expect_false(is.unsorted(s$x))                 # original order preserved

  capped <- samplerows(d, 100, by = "g")        # n above a group size caps
  expect_equal(nrow(capped), nrow(d))

  f <- samplefrac(d, 0.5, by = "g")
  expect_equal(as.integer(table(f$g)), c(2L, 4L, 6L))

  expect_equal(nrow(samplerows(d, 5)), 5L)       # ungrouped unchanged
})

test_that("subset with by evaluates the predicate per group", {
  set.seed(1)
  d <- data.frame(g = rep(c("a", "b"), each = 20), x = rnorm(40), id = 1:40,
                  stringsAsFactors = FALSE)

  got <- as.data.frame(subset(d, x > mean(x), by = "g"))
  ref <- do.call(rbind, lapply(base::split(d, d$g),
                               function(s) s[s$x > mean(s$x), ]))
  ref <- ref[order(ref$id), ]
  rownames(got) <- rownames(ref) <- NULL
  expect_equal(got, ref, ignore_attr = TRUE)

  # select still applies alongside by
  got2 <- as.data.frame(subset(d, x > mean(x), select = c("g", "id"), by = "g"))
  expect_named(got2, c("g", "id"))

  # a non-grouped predicate gives the same rows as the ungrouped call
  expect_equal(
    as.data.frame(subset(d, x > 0, by = "g")),
    as.data.frame(subset(d, x > 0)),
    ignore_attr = TRUE
  )
})

test_that("orderrows supports a direction for each sort column", {
  df <- data.frame(
    group = c("b", "a", "b", "a"),
    score = c(1, 1, 2, 2),
    id = 1:4
  )

  out <- orderrows(
    df,
    by = c("group", "score"),
    decreasing = c(FALSE, TRUE)
  )

  expect_equal(out$id, c(4, 2, 3, 1))
  expect_s3_class(out, "basetable")
  expect_equal(df$id, 1:4)
})

test_that("firstby/lastby pick one row per group", {
  df <- data.frame(g = c("a", "a", "b"), v = c(1, 2, 3))

  expect_equal(firstby(df, "g")$v, c(1, 3))
  expect_equal(lastby(df, "g")$v, c(2, 3))
})

test_that("removeduplicates honors by= and keep=", {
  df <- data.frame(id = c(1, 1, 2), v = c("a", "b", "c"), stringsAsFactors = FALSE)

  expect_equal(removeduplicates(df, by = "id", keep = "first")$v, c("a", "c"))
  expect_equal(removeduplicates(df, by = "id", keep = "last")$v, c("b", "c"))
  expect_equal(nrow(removeduplicates(df, by = "id", keep = "none")), 1L)
  expect_equal(nrow(removeduplicates(data.frame(x = c(1, 1, 2)))), 2L)
  expect_equal(removeduplicates(data.frame(x = c(1, 1, 2, 3, 3, 3)), keep = "none")$x, 2)
})