#!/usr/bin/env bash

build_xpath_string() {
  if ! check_param_count_gt "XML tree" 1 $#; then
    return 1
  fi
  if ! build_xpath_string_for_element "$@"; then
    return 1
  fi
  xpath+='/text()'
}

build_xpath_string_for_element() {
  if ! check_param_count_gt "XML tree" 1 $#; then
    return 1
  fi
  xpath='//'
  for ((idx=1;idx<=$#;idx++)); do
    xpath+='*[local-name()="'${!idx}'"]'
    if [ "$idx" != $# ]; then
      xpath+='/'
    fi
  done
}

check_for_empty_element() {
  if ! check_param_count_gt "data file, XML tree" 2 $#; then
    return 1
  fi

  # shellcheck disable=SC2068
  if ! build_xpath_string_for_element ${@:2}; then
    log 2 "error building XPath search string"
    return 1
  fi
  if ! get_xml_data "$1" "$1.xml"; then
    log 2 "error getting XML data"
    return 1
  fi
  if grep -q '<[^/][^ >]*>' "$1.xml"; then
    if xmllint --xpath "${xpath}[not(normalize-space())]" "$1.xml" 1>/dev/null 2>&1; then
      return 0
    fi
  fi
  return 1
}

get_element() {
  if ! check_param_count_gt "data file, XML tree" 2 $#; then
    return 1
  fi

  if ! build_xpath_string_for_element "${@:2}"; then
    log 2 "error building XPath search string"
    return 1
  fi
  if ! xml_val=$(grep '<[^/][^ >]*>' "$1" | xmllint --xpath "$xpath" - 2>&1); then
    log 2 "error getting XML value matching $xpath: $xml_val (file data: $(cat "$1"))"
    return 1
  fi
  echo "$xml_val"
}

get_element_text() {
  if [ $# -lt 2 ]; then
    log 2 "'get_element_text' requires data file, XML tree"
    return 1
  fi

  if ! build_xpath_string_for_element "${@:2}"; then
    log 2 "error building XPath search string"
    return 1
  fi

  log 5 "data: $(cat "$1")"
  log 5 "xpath: $xpath"
  if ! get_xml_data "$1" "$1.xml"; then
    log 2 "error getting XML data"
    return 1
  fi
  log 5 "result: $(xmllint --xpath "boolean($xpath)" "$1.xml" 2>&1)"
  result=$(xmllint --xpath "boolean($xpath)" "$1.xml" 2>&1)
  if [ "$result" == "false" ]; then
    log 2 "element matching '$xpath' doesn't exist"
    return 1
  fi
  if ! xml_val=$(xmllint --xpath "${xpath}/text()" "$1.xml" 2>/dev/null); then
    echo ""
    return 0
  fi
  echo "$xml_val"
}

check_xml_element() {
  if [ $# -lt 3 ]; then
    log 2 "'check_xml_element' requires data source, expected value, XML tree"
    return 1
  fi
  if ! xml_val=$(get_element_text "$1" "${@:3}"); then
    log 2 "error getting element text"
    return 1
  fi
  if [ "$2" != "$xml_val" ]; then
    log 2 "XML data mismatch, expected '$2', actual '$xml_val'"
    return 1
  fi
  return 0
}

check_xml_element_contains() {
  if [ $# -lt 3 ]; then
    log 2 "'check_xml_element_contains' requires data source, expected value, XML tree"
    return 1
  fi
  if [ "$2" == "" ]; then
    if ! check_for_empty_element "$1" "${@:3}"; then
      log 2 "Message value not empty"
      return 1
    fi
    return 0
  else
    if ! xml_val=$(get_element_text "$1" "${@:3}"); then
      log 2 "error getting element text"
      return 1
    fi
  fi
  if [[ "$xml_val" != *"$2"* ]]; then
    log 2 "XML data mismatch, expected '$2', actual '$xml_val'"
    return 1
  fi
  return 0
}

check_xml_error_contains() {
  if [ "$#" -ne 3 ]; then
    log 2 "'check_xml_code_error_contains' requires data source, expected error, string"
    return 1
  fi
  if ! check_xml_element "$1" "$2" "Error" "Code"; then
    log 2 "error checking xml error code"
    return 1
  fi
  if ! check_xml_element_contains "$1" "$3" "Error" "Message"; then
    log 2 "error checking xml element"
    return 1
  fi
  return 0
}

check_xml_error_contains_with_single_error_field() {
  if ! check_param_count_v2 "data source, expected error, string, expected key, expected value" 5 $#; then
    return 1
  fi
  if ! check_xml_error_contains "$1""$2" "$3"; then
    log 2 "error checking initial xml error"
    return 1
  fi
  if ! check_error_parameter "$1" "$4" "$5"; then
    log 2 "error checking error parameter"
    return 1
  fi
  return 0
}

get_xml_data() {
  if ! check_param_count_v2 "data file, output file" 2 $#; then
    return 1
  fi
  log 5 "data: $(cat "$1")"

  # Find first line with "<?xml" and everything from there onward
  xml_start=$(grep -n "<?xml" "$1" | head -n 1 | cut -d: -f1)

  if [ -z "$xml_start" ]; then
    # Try any tag
    xml_start=$(grep -n "<[^>]*>" "$1" | head -n 1 | cut -d: -f1)
    if [ -z "$xml_start" ]; then
      log 2 "No XML declaration found."
      return 1
    fi
  fi
  log 5 "xml start: $xml_start"

  # Grab everything from the XML start line to the end of the file
  tail -n +"$xml_start" "$1" > "$2"
  log 5 "xml data after start: $(cat "$2")"

  # Try to extract valid XML using xmllint recover mode
  # This will truncate anything after the root closing tag
  truncated=$(xmllint --recover --noent --nocdata "$2" 2>/dev/null |
    awk 'BEGIN{xml=0}
         /<\?xml/{xml=1}
         {if (xml) print}
         /<\/[^>]+>/{lastline=NR}
         END{exit}')
  echo -n "$truncated" > "$2"
}

check_error_parameter() {
  if ! check_param_count_v2 "data file, XML parameter, expected value" 3 $#; then
    return 1
  fi
  if ! value=$(get_element_text "$1" "Error" "$2" 2>&1); then
    log 2 "error getting argument name: $value"
    return 1
  fi
  unescaped_value="$(xmlstarlet unesc "$value")"
  if [ "$unescaped_value" != "$3" ]; then
    log 2 "expected '$3', was '$unescaped_value'"
    return 1
  fi
  return 0
}