#!/usr/bin/env bash
set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
# shellcheck source=00_env.sh
. "$SCRIPT_DIR/00_env.sh"

EXECUTE=false
LOG_PATH="/var/log"
DAYS_OLD=14

usage() {
  printf 'Usage: %s [--path <path>] [--days-old <N>] [--execute]\n' "$(basename "$0")"
}

while [[ "$#" -gt 0 ]]; do
  case "$1" in
    --path) LOG_PATH="${2:-}"; shift 2 ;;
    --days-old) DAYS_OLD="${2:-}"; shift 2 ;;
    --execute) EXECUTE=true; DRY_RUN=false; shift ;;
    -h|--help) usage; exit 0 ;;
    *) critical "Unknown argument: $1"; usage; exit 2 ;;
  esac
done

if ! [[ "$DAYS_OLD" =~ ^[0-9]+$ ]] || (( DAYS_OLD < 1 )); then
  critical "--days-old must be a positive integer"
  exit 2
fi

validate_path "$LOG_PATH" || exit 2
require_cmd find || exit 1
require_cmd sort || exit 1
require_cmd xargs || true

section "Large Log Files In $LOG_PATH"
find "$LOG_PATH" -xdev -type f \( -name '*.log' -o -name '*log' -o -name 'messages*' -o -name 'syslog*' \) -size +100M -printf '%s\t%p\n' 2>/dev/null |
  sort -rn |
  awk '
    function human(bytes) {
      split("B KB MB GB TB", unit)
      size = bytes
      idx = 1
      while (size >= 1024 && idx < 5) {
        size = size / 1024
        idx++
      }
      return sprintf("%.1f%s", size, unit[idx])
    }
    { size = $1; $1 = ""; sub(/^\t/, ""); printf "%10s  %s\n", human(size), $0 }
  ' | tee -a "$LOG_FILE"

section "Old Rotated Logs Eligible For Review"
mapfile -t rotated_logs < <(
  find "$LOG_PATH" -xdev -type f \
    \( -name '*.gz' -o -name '*.1' -o -name '*.old' -o -name '*.bz2' -o -name '*.xz' \) \
    -mtime +"$DAYS_OLD" -print 2>/dev/null | sort
)

if [[ "${#rotated_logs[@]}" -eq 0 ]]; then
  ok "No old rotated logs found under $LOG_PATH with age greater than $DAYS_OLD days."
else
  printf '%s\n' "${rotated_logs[@]}" | tee -a "$LOG_FILE"
fi

section "Suggested Cleanup Commands"
cat <<SUGGESTIONS | tee -a "$LOG_FILE"
# Review large active logs before truncating. Prefer application-aware log rotation:
logrotate -d /etc/logrotate.conf

# Remove old rotated logs only after retention approval:
$(basename "$0") --path "$LOG_PATH" --days-old "$DAYS_OLD" --execute
SUGGESTIONS

if [[ "$EXECUTE" != "true" ]]; then
  ok "Safe mode. No logs were removed."
  exit 0
fi

if [[ "${#rotated_logs[@]}" -eq 0 ]]; then
  ok "Execution requested, but there are no eligible old rotated logs to remove."
  exit 0
fi

confirm_execute "remove old rotated logs from $LOG_PATH"

for file in "${rotated_logs[@]}"; do
  if [[ -f "$file" && ! -L "$file" ]]; then
    run_cmd rm -f -- "$file"
  else
    warning "Skipped non-regular file or symlink: $file"
  fi
done

ok "Old rotated log cleanup completed."