#!/bin/bash

set -e

## Global var
SCRIPT_NAME="${0##*/}"

## Style
RED='\e[31m'
GREEN='\e[32m'
BLUE='\e[34m'
YELLOW='\e[93m'
BOLD='\e[1m'
DIM='\e[2m'
ITALIC='\e[3m'
N='\e[0m'

## Util function
die(){
  if [ -n "$BASH_LINENO" ];then
    err "${SCRIPT_NAME}: ${BOLD}Error:Line:${BASH_LINENO[0]}${N} $*" >&2
  else
    err "${SCRIPT_NAME}: ${BOLD}Error${N} $*" >&2
  fi
  exit 1
}

msg(){
  echo -e "${GREEN}[+]${N} $*"
}

info(){
  echo -e "${BLUE}[-]${N} $*"
}

err(){
  echo -e "${RED}[x]${N} $*" >&2
}

show_help() {
  echo "Usage: $SCRIPT_NAME [--xml XML] [-h] [-v]"
  echo
  echo "Options:"
  echo "  --xml XML      Specify the path to web.xml (default web.xml)"
  echo "  -v, --verbose  Increase verbosity"
  echo "  -h, --help     Display this help message"
}

show_progress() {
  local width=50
  local percent=$(( 100 * $1 / $2 ))
  local filled=$(( width * $1 / $2 ))
  local empty=$(( width - filled ))

  local fill_char=$(printf " %.0s" {1..101})

  printf "\r["
  printf "\e[47m"
  printf "%.*s" "$filled" "$fill_char"
  printf "\e[0m"
  printf "%.*s" "$empty" "$fill_char"
  printf "] %3d%% (%d/%d)" "$percent" "$1" "$2"

  if [ "$1" -eq "$2" ]; then
    echo ""  # move to next line when complete
  fi
  # Show progress arg 1 is count and arg 2 is the total
  # echo -en "\r${BLUE}[-]${N} Progress ${DIM}$percent${N}/${BOLD}100%${N}\e[K"
  # echo -en "\r[] $1/$2\e[K"
}

if ! command -v xq 2&>/dev/null;then
  err "Command xq not found, please run: ${BOLD}pip3 install yq${N}"
fi

if ! command -v jq 2&>/dev/null;then
  err "Command jq not found, please run: ${BOLD}sudo apt install -y jq${N}"
fi

WEB_XML="web.xml"
VERBOSE=0
while [[ "$#" -gt 0 ]]; do
  case "$1" in
    -h)
      show_help
      exit 0
      ;;
    --xml)
      if [[ -n "$2" && "$2" != -* ]]; then
        WEB_XML="$2"
        shift
      else
        echo "Error: --xml requires valid xml"
        exit 1
      fi
      ;;
    -v|--verbose)
      VERBOSE=1
      ;;
    *)
      echo "Unknown option: $1"
      show_help
      exit 1
      ;;
  esac
  shift
done

if [ ! -f "$WEB_XML" ];then
  err "File not found: $WEB_XML"
  exit 1
fi

if [ "$VERBOSE" -eq 1 ];then
  info "Processing $WEB_XML"
  info "Recovering ${GREEN}servlets${N} ${ITALIC}${DIM}(can take some time)${N}"
fi

# Parse all servlet mappings into a lookup: servlet-name -> list of url-patterns
declare -A servlet_class_map
declare -A servlet_urls_map

xq_output=$(xq -c '
  .["web-app"]["servlet"][] as $s
  | {
      name: $s["servlet-name"],
      class: $s["servlet-class"],
      urls: (
        .["web-app"]["servlet-mapping"] 
        | map(select(.["servlet-name"] == $s["servlet-name"])["url-pattern"])
        | flatten
      )
    }
' $WEB_XML)

count=1
total_lines=$(printf "%s\n" "$xq_output" |wc -l)
while IFS= read -r entry; do
  if [ "$VERBOSE" -eq 1 ];then
    show_progress "$count" "$total_lines"
    let "count=count+1"
  fi
  name=$(jq -r '.name' <<< "$entry")
  class=$(jq -r '.class' <<< "$entry")
  urls=$(jq -r '.urls[]' <<< "$entry" | paste -sd "|" -)
  servlet_class_map["$name"]="$class"
  servlet_urls_map["$name"]="$urls"
done < <(printf "%s\n" "$xq_output")

if [ "$VERBOSE" -eq 1 ];then
  info "Recovering ${GREEN}filters${N}"
fi

# Parse all filters and map filter-name to list of patterns
declare -A filter_class_map
declare -A filter_patterns_map

xq_output=$(xq -c '
  .["web-app"]["filter"][] as $f
  | {
      name: $f["filter-name"],
      class: $f["filter-class"],
      patterns: (
        .["web-app"]["filter-mapping"] 
        | map(select(.["filter-name"] == $f["filter-name"])["url-pattern"])
        | flatten
      )
    }
' $WEB_XML)

count=1
total_lines=$(printf "%s\n" "$xq_output" |wc -l)
while IFS= read -r entry; do
  if [ "$VERBOSE" -eq 1 ];then
    show_progress "$count" "$total_lines"
    let "count=count+1"
  fi
  name=$(jq -r '.name' <<< "$entry")
  class=$(jq -r '.class' <<< "$entry")
  patterns=$(jq -r '.patterns[]' <<< "$entry" | paste -sd "|" -)
  filter_class_map["$name"]="$class"
  filter_patterns_map["$name"]="$patterns"
done < <(printf "%s\n" "$xq_output")

# Process each servlet
for servlet in "${!servlet_class_map[@]}"; do
  class="${servlet_class_map[$servlet]}"
  IFS='|' read -ra urls <<< "${servlet_urls_map[$servlet]}"
  declare -A filter_set=()

  # Match servlet URLs with all filter patterns
  for filter in "${!filter_patterns_map[@]}"; do
    IFS='|' read -ra patterns <<< "${filter_patterns_map[$filter]}"
    for u in "${urls[@]}"; do
      for p in "${patterns[@]}"; do
        regex="^${p//\*/.*}$"
        if [[ "$u" =~ $regex ]]; then
          filter_set["$filter"]=1
        fi
      done
    done
  done

  # Output result
  echo -e "Servlet : ${GREEN}${servlet}${N}"
  echo -e "  Class : ${BOLD}${class}${N}"
  echo -e "  URLs  :"
  for u in "${urls[@]}"; do echo "    - $u"; done
    echo "  Filters:"
    if [[ ${#filter_set[@]} -eq 0 ]]; then
      echo "    (none)"
    else
      for f in "${!filter_set[@]}"; do
        echo "    - $f"
      done
    fi
    echo
done