#!/usr/bin/env bash
#
# send_dir.sh — upload every file in a directory to a running FileServer.
#
# Each file is POSTed to /upload as multipart/form-data. By default one file per
# request (so you get per-file feedback); use -b to batch all files into a
# single request instead.
#
# Usage:
#   bin/send_dir.sh [-u URL] [-b] [-r] DIR
#
#   DIR         directory whose files are uploaded
#   -u URL      server base URL (default: http://127.0.0.1:8080, or $FS_URL)
#   -b          batch: send all files in one multipart request
#   -r          recurse into subdirectories
#   -j N        upload up to N files concurrently (default: 1). A slow big
#               file no longer blocks the others; results are tallied at the end.
#
# Examples:
#   bin/send_dir.sh data/samples
#   bin/send_dir.sh -u http://host:9000 -b -r ~/Downloads
set -euo pipefail

url="${FS_URL:-http://127.0.0.1:8080}"
batch=0
recurse=0
jobs=1

while getopts ":u:brj:h" opt; do
  case "$opt" in
    u) url="$OPTARG" ;;
    b) batch=1 ;;
    r) recurse=1 ;;
    j) jobs="$OPTARG" ;;
    h) sed -n '2,22p' "$0"; exit 0 ;;
    \?) echo "unknown option: -$OPTARG" >&2; exit 2 ;;
    :) echo "option -$OPTARG needs an argument" >&2; exit 2 ;;
  esac
done
shift $((OPTIND - 1))

if ! [[ "$jobs" =~ ^[0-9]+$ ]] || [[ "$jobs" -lt 1 ]]; then
  echo "-j needs a positive integer, got: $jobs" >&2
  exit 2
fi

dir="${1:-}"
if [[ -z "$dir" ]]; then
  echo "usage: $0 [-u URL] [-b] [-r] DIR" >&2
  exit 2
fi
if [[ ! -d "$dir" ]]; then
  echo "not a directory: $dir" >&2
  exit 2
fi

endpoint="${url%/}/upload"

# Collect regular files (optionally recursive), NUL-safe for odd filenames.
mapfile -d '' files < <(
  if [[ "$recurse" -eq 1 ]]; then
    find "$dir" -type f -print0
  else
    find "$dir" -maxdepth 1 -type f -print0
  fi
)

if [[ "${#files[@]}" -eq 0 ]]; then
  echo "no files found in $dir" >&2
  exit 1
fi

echo "uploading ${#files[@]} file(s) from '$dir' to $endpoint"

if [[ "$batch" -eq 1 ]]; then
  # One request with every file. Each -F field name is arbitrary; the server
  # keys off the filename, so we just number them.
  args=()
  i=0
  for f in "${files[@]}"; do
    args+=(-F "f${i}=@${f}")
    i=$((i + 1))
  done
  code=$(curl -sS -o /dev/stderr -w '%{http_code}' "${args[@]}" "$endpoint")
  echo
  echo "-> HTTP $code"
  [[ "$code" == "202" ]]
else
  # One request per file, up to $jobs in flight at once. Each upload runs in the
  # background so a slow (big) file doesn't stall the ones behind it. Every job
  # writes its HTTP status to a per-file line in $results; we tally after all
  # jobs drain.
  results="$(mktemp)"
  trap 'rm -f "$results"' EXIT

  # Upload one file: print progress and append "code<TAB>path" to $results.
  upload_one() {
    local f="$1" code
    code=$(curl -sS -o /dev/stderr -w '%{http_code}' -F "file=@${f}" "$endpoint")
    echo "  -> HTTP $code  ${f}"
    printf '%s\t%s\n' "$code" "$f" >> "$results"
  }

  for f in "${files[@]}"; do
    # Throttle: wait for a slot to free up before launching the next upload.
    # (|| true: a failed upload's exit status must not trip `set -e` here.)
    while (( $(jobs -r -p | wc -l) >= jobs )); do
      wait -n || true
    done
    upload_one "$f" &
  done
  wait || true

  ok=$(grep -c $'^202\t' "$results" || true)
  fail=$(( ${#files[@]} - ok ))
  echo "done: $ok accepted, $fail failed"
  [[ "$fail" -eq 0 ]]
fi