test_that("str_split works", {
  expect_equal(stringr::str_split_fixed("sex", "\\|", n = 2)[, 2], "")
  expect_equal(stringr::str_split_1("sex", "\\+"), "sex")
  expect_equal(stringr::str_split_1("sex+age", "\\+"), c("sex", "age"))
})

test_that("basic use works", {
  df1 <- letters_n()
  df2 <- data.frame(clnt_id = 1:nrow(df1), sex = sample(c("F", "M"), nrow(df1), replace = TRUE))
  out_df <- fetch_var(df1,
    keys = clnt_id,
    linkage = list(df2 ~ sex)
  )
  expect_in(out_df$sex, c(df2$sex, NA))
})

test_that("multiple keys works", {
  df1 <- letters_n()
  df2 <- data.frame(
    clnt_id = 1:nrow(df1), sex = sample(c("F", "M"), nrow(df1), replace = TRUE),
    ans = sample(c("all", "any", "noise"), nrow(df1), replace = TRUE)
  )
  out_df <- fetch_var(df1,
    keys = c(clnt_id, ans),
    linkage = list(df2 ~ sex)
  )
  expect_in(out_df$sex, c(df2$sex, NA))
})

test_that("subset of keys works", {
  df1 <- letters_n()
  df2 <- data.frame(
    clnt_id = 1:nrow(df1), sex = sample(c("F", "M"), nrow(df1), replace = TRUE),
    ans = sample(c("all", "any", "noise"), nrow(df1), replace = TRUE),
    diagx = sample(letters, nrow(df1), replace = TRUE)
  )
  out_df <- fetch_var(df1,
    keys = c(clnt_id, ans, diagx),
    linkage = list(df2 ~ sex | clnt_id)
  )
  expect_in(out_df$sex, c(df2$sex, NA))
  out_df <- fetch_var(df1,
    keys = c(clnt_id, ans, diagx),
    linkage = list(df2 ~ sex | clnt_id + ans)
  )
  expect_in(out_df$sex, c(df2$sex, NA))
  out_df <- fetch_var(df1,
    keys = c(clnt_id, ans, diagx),
    linkage = list(df2 ~ sex | clnt_id + ans + diagx)
  )
  expect_in(out_df$sex, c(df2$sex, NA))
})

test_that("multiple sources works", {
  df1 <- letters_n()
  df2 <- data.frame(
    clnt_id = 1:nrow(df1), sex = sample(c("F", "M"), nrow(df1), replace = TRUE),
    ans = sample(c("all", "any", "noise"), nrow(df1), replace = TRUE)
  )
  db3 <- dbplyr::memdb_frame(
    clnt_id = 1:nrow(df1), age = sample(0:100, nrow(df1), replace = TRUE),
    ans = sample(c("all", "any", "noise"), nrow(df1), replace = TRUE)
  )
  out_df <- fetch_var(df1,
    keys = c(clnt_id, ans),
    linkage = list(
      df2 ~ sex,
      db3 ~ age
    ),
    copy = TRUE
  )
  expect_in(out_df$sex, c(df2$sex, NA))
  expect_in(out_df$age, c(dplyr::pull(db3, age), NA))
})

test_that("multiple keys works", {
  df1 <- letters_n()
  df2 <- data.frame(
    clnt_id = 1:nrow(df1), sex = sample(c("F", "M"), nrow(df1), replace = TRUE),
    ans = sample(c("all", "any", "noise"), nrow(df1), replace = TRUE)
  )
  out_df <- fetch_var(df1,
    keys = c(clnt_id, ans),
    linkage = list(df2 ~ sex)
  )
  expect_in(out_df$sex, c(df2$sex, NA))
})

test_that("n of keys check works", {
  df1 <- letters_n()
  df2 <- data.frame(
    clnt_id = 1:nrow(df1), sex = sample(c("F", "M"), nrow(df1), replace = TRUE),
    ans = sample(c("all", "any", "noise"), nrow(df1), replace = TRUE)
  )
  expect_error(
    fetch_var(df1,
      keys = clnt_id,
      linkage = list(df2 ~ sex | clnt_id + ans)
    ),
    "length of variables"
  )
  # also test var not in keys
  expect_error(
    fetch_var(df1,
      keys = clnt_id,
      linkage = list(df2 ~ sex | ans)
    ),
    "subset of keys"
  )
})

test_that("not one to one warning works", {
  df1 <- letters_n(id = 1:5)
  df2 <- data.frame(clnt_id = c(1:5, 1:5), sex = c(rep("F", 5), rep("M", 5)))
  expect_error(fetch_var(df1,
    keys = clnt_id,
    linkage = list(df2 ~ sex)
  ), "not one to one") %>%
    expect_warning()
})

test_that("database x works", {
  db1 <- letters_n(type = "database")
  df1 <- dplyr::collect(db1)
  df2 <- data.frame(clnt_id = 1:nrow(df1), sex = sample(c("F", "M"), nrow(df1), replace = TRUE))
  db3 <- dbplyr::memdb_frame(
    clnt_id = 1:nrow(df1), age = sample(0:100, nrow(df1), replace = TRUE),
    ans = sample(c("all", "any", "noise"), nrow(df1), replace = TRUE)
  )
  out_df <- fetch_var(db1,
    keys = c(clnt_id, ans),
    linkage = list(
      df2 ~ sex|clnt_id,
      db3 ~ age
    ),
    copy = TRUE
  ) %>%
    dplyr::collect()
  expect_in(out_df$sex, c(df2$sex, NA))
  expect_in(out_df$age, c(dplyr::pull(db3, age), NA))
})