# =========================
# 1) SAVE: Zip thư mục R library hiện tại
# =========================
save_r_lib_zip <- function(zip_out = "/content/R_library.zip",
                           lib_dir = .libPaths()[1],
                           zip_flags = "-r9X") {

  stopifnot(dir.exists(lib_dir))
  old <- getwd()
  on.exit(setwd(old), add = TRUE)

  setwd(dirname(lib_dir))
  utils::zip(zipfile = zip_out, files = basename(lib_dir), flags = zip_flags)

  message("✅ Saved R library to: ", zip_out)
  return(zip_out)
}


# =========================
# 2) LOAD: Unzip rồi dán đè packages vào R library hiện tại
# =========================
load_r_lib_zip <- function(zip_path,
                           unpack_root = "/content/R_site_library_unpacked",
                           add_to_libpaths = TRUE,
                           backup = FALSE,
                           backup_dir = "/content",
                           sync_to_target = FALSE,
                           target_lib = "/content/R_site_library",
                           overwrite = TRUE,
                           quiet = FALSE) {

  if (!file.exists(zip_path)) stop("Zip file not found: ", zip_path)

  # B1) (optional) backup target_lib nếu bạn sync đè vào đó
  backup_tar <- NULL
  if (backup && sync_to_target) {
    dir.create(target_lib, recursive = TRUE, showWarnings = FALSE)
    backup_tar <- file.path(
      backup_dir,
      sprintf("R_lib_backup_%s.tar.gz", format(Sys.time(), "%Y%m%d_%H%M%S"))
    )
    old <- getwd(); on.exit(setwd(old), add = TRUE)
    setwd(dirname(target_lib))
    utils::tar(backup_tar, files = basename(target_lib), compression = "gzip")
    if (!quiet) message("🗄️ Backup saved: ", backup_tar)
  }

  # B2) Unpack zip
  unlink(unpack_root, recursive = TRUE, force = TRUE)
  dir.create(unpack_root, recursive = TRUE, showWarnings = FALSE)
  utils::unzip(zipfile = zip_path, exdir = unpack_root, overwrite = overwrite)

  # B3) Auto-detect best lib dir (chứa nhiều package nhất)
  desc_files <- list.files(unpack_root, pattern = "^DESCRIPTION$", recursive = TRUE, full.names = TRUE)
  if (length(desc_files) == 0) stop("Không thấy DESCRIPTION trong zip -> không phải thư viện R chuẩn.")

  pkg_dirs <- unique(dirname(desc_files))   # .../<pkg>
  lib_dirs <- unique(dirname(pkg_dirs))     # .../<lib> (vd .../site-library)

  pkg_count <- sapply(lib_dirs, function(d) length(list.dirs(d, recursive = FALSE, full.names = TRUE)))
  best_lib <- lib_dirs[which.max(pkg_count)]

  if (!quiet) {
    message("Best lib dir = ", best_lib)
    message("Packages in best lib = ", max(pkg_count))
  }

  # B4) Add best_lib vào .libPaths()
  if (add_to_libpaths) {
    .libPaths(c(best_lib, .libPaths()))
    if (!quiet) { message("Library paths now:"); print(.libPaths()) }
  }

  # B5) (optional) Sync/copy đè best_lib -> target_lib (writable)
  overwritten <- NA_integer_
  if (sync_to_target) {
    dir.create(target_lib, recursive = TRUE, showWarnings = FALSE)

    # copy từng package folder
    pkgs <- list.dirs(best_lib, recursive = FALSE, full.names = TRUE)
    pkgs <- pkgs[file.exists(file.path(pkgs, "DESCRIPTION"))]

    for (src in pkgs) {
      pkg <- basename(src)
      dest <- file.path(target_lib, pkg)
      unlink(dest, recursive = TRUE, force = TRUE)
      system2("bash", c("-lc", paste("cp -a", shQuote(src), shQuote(target_lib))))
    }
    overwritten <- length(pkgs)

    # ưu tiên target_lib nếu bạn muốn dùng nó thay vì best_lib
    .libPaths(c(target_lib, .libPaths()))
    if (!quiet) message("✅ Synced packages to target_lib: ", target_lib, " (", overwritten, " pkgs)")
  }

  invisible(list(
    zip_path = zip_path,
    unpack_root = unpack_root,
    best_lib = best_lib,
    added_to_libpaths = add_to_libpaths,
    synced = sync_to_target,
    target_lib = if (sync_to_target) target_lib else NULL,
    overwritten = overwritten,
    backup_tar = backup_tar
  ))
}


load_r_lib_full <- function(url  = "https://huggingface.co/datasets/TommyNgx/R_library_101/resolve/main/R_library3.zip",
                            dest = "/content/R_library3.zip",
                            remove_existing = TRUE,
                            quiet = FALSE,
                            ...) {
  # url: link zip trên Hugging Face
  # dest: nơi lưu file zip (vd /content/R_library3.zip)
  # ...: truyền thêm tham số cho load_r_lib_zip(), ví dụ quiet=TRUE, sync_to_target=TRUE,...

  # 0) Xoá file cũ cho lẹ
  if (remove_existing && file.exists(dest)) {
    unlink(dest, force = TRUE)
    if (!quiet) message("🧹 Removed existing: ", dest)
  }

  # 1) Tải xuống
  if (!requireNamespace("curl", quietly = TRUE)) {
    install.packages("curl")
  }
  curl::curl_download(url, destfile = dest, quiet = quiet)

  if (!quiet) {
    message("⬇️ Downloaded to: ", dest, " (", file.info(dest)$size, " bytes)")
  }

  # 2) Load / restore library từ zip vừa tải
  # mặc định sẽ dùng load_r_lib_zip() của bạn
  out <- load_r_lib_zip(dest, quiet = quiet, ...)

  invisible(out)
}


setup_vietnamese_plot <- function(font_name = "Noto Sans",
                                  family = "noto",
                                  locale = "C.UTF-8",
                                  install_if_missing = TRUE,
                                  quiet = TRUE) {

  # 1) Locale UTF-8
  try(Sys.setlocale("LC_ALL", locale), silent = TRUE)

  # 2) Cài package nếu thiếu
  if (install_if_missing) {
    if (!requireNamespace("showtext", quietly = TRUE)) install.packages("showtext", quiet = quiet)
    if (!requireNamespace("sysfonts", quietly = TRUE)) install.packages("sysfonts", quiet = quiet)
  }

  # 3) Load
  suppressPackageStartupMessages(library(showtext))
  suppressPackageStartupMessages(library(sysfonts))

  # 4) Add font (nếu đã add rồi thì bỏ qua)
  current_fonts <- try(sysfonts::font_families(), silent = TRUE)
  if (inherits(current_fonts, "try-error") || !(family %in% current_fonts)) {
    sysfonts::font_add_google(font_name, family)
  }

  # 5) Bật showtext
  showtext::showtext_auto()

  invisible(list(locale = Sys.getlocale("LC_ALL"), family = family, font_name = font_name))
}