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

TIMESTAMP="${TIMESTAMP:-$(date +%Y%m%d_%H%M%S)}"
DRY_RUN="${DRY_RUN:-true}"
LOG_FILE="${LOG_FILE:-/tmp/disk_full_${TIMESTAMP}.log}"
WARN_THRESHOLD="${WARN_THRESHOLD:-80}"
CRIT_THRESHOLD="${CRIT_THRESHOLD:-90}"
EMERGENCY_THRESHOLD="${EMERGENCY_THRESHOLD:-95}"

log() {
  local level="$1"
  shift
  local message="$*"

  printf '%s: %s\n' "$level" "$message" | tee -a "$LOG_FILE"
}

ok() {
  log "OK" "$@"
}

warning() {
  log "WARNING" "$@"
}

critical() {
  log "CRITICAL" "$@"
}

section() {
  printf '\n== %s ==\n' "$1" | tee -a "$LOG_FILE"
}

require_cmd() {
  local cmd="$1"

  if command -v "$cmd" >/dev/null 2>&1; then
    return 0
  fi

  warning "Command not available: $cmd"
  return 1
}

run_cmd() {
  if [[ "$#" -eq 0 ]]; then
    critical "run_cmd called without a command"
    return 2
  fi

  if [[ "$DRY_RUN" == "true" ]]; then
    ok "DRY-RUN: $*"
    return 0
  fi

  ok "RUN: $*"
  "$@" 2>&1 | tee -a "$LOG_FILE"
}

confirm_execute() {
  local target="${1:-disk-full remediation}"

  if [[ "$DRY_RUN" == "true" ]]; then
    ok "Safe mode enabled. No destructive actions will be taken."
    return 0
  fi

  warning "Execution mode requested for: $target"
  warning "Confirm the affected filesystem, application impact, backups, and change approval before continuing."
  printf 'Type EXECUTE to continue: '
  read -r confirmation

  if [[ "$confirmation" != "EXECUTE" ]]; then
    critical "Confirmation failed. Aborting."
    exit 1
  fi

  ok "Execution confirmed by operator."
}

validate_path() {
  local path="$1"

  if [[ -z "$path" ]]; then
    critical "Path cannot be empty"
    return 2
  fi

  if [[ ! -e "$path" ]]; then
    critical "Path does not exist: $path"
    return 2
  fi
}

usage_percent_number() {
  local value="$1"
  printf '%s\n' "${value%\%}"
}

status_for_percent() {
  local percent="$1"

  if (( percent >= EMERGENCY_THRESHOLD )); then
    printf 'CRITICAL'
  elif (( percent >= CRIT_THRESHOLD )); then
    printf 'WARNING'
  elif (( percent >= WARN_THRESHOLD )); then
    printf 'WARNING'
  else
    printf 'OK'
  fi
}

safe_find_prune_args() {
  printf '%s\n' \
    -path /proc -o \
    -path /sys -o \
    -path /dev -o \
    -path /run -o \
    -path /tmp/systemd-private-\*
}