packages <- c(
  # Core workflow
  "tidyverse",
  "knitr",
  "broom",
  "readr",
  "readxl",
  "tibble",
  "tidyr",
  "dplyr",
  # Regression helpers used early in the course
  "car",
  "lm.beta",
  "carData",
  "effectsize",
  "DescTools",
  "rstatix",
  "standardize",
  "interactions",
  "corrplot",
  "ellipse",
  "MASS",
  "boot",
  # Models used in the course
  "lme4",
  "lmerTest",
  "MuMIn",
  "rms",
  "emmeans",
  "lavaan",
  "metafor",
  "dmetar",
  # Diagnostics / reporting helpers
  "performance",
  "parameters",
  "ggplot2",
  "ggpubr",
  "scales",
  "viridis",
  "pander",
  "shiny",
  "tigerstats"
)

if (is.null(getOption("repos")) || getOption("repos")[["CRAN"]] == "@CRAN@") {
  options(repos = c(CRAN = "https://cloud.r-project.org"))
}

installed <- rownames(installed.packages())
to_install <- setdiff(packages, installed)

if (length(to_install) == 0) {
  message("All required packages are already installed.")
} else {
  message("Installing packages: ", paste(to_install, collapse = ", "))
  install.packages(to_install)
  message("Done.")
}