algorithm

#!/bin/bash

MODE="unknown"
LANG="unknown"
EXT=""
PLATFORM=""
PROBLEM_NUMBER=""
PROBLEM_NAME=""
PROBLEM_URL=""
DATE=$(date +%F)

function LANGUAGE_MAPPING {
  case $1 in
    c++|cpp|cc)
      EXT="cpp"
      ;;
    go)
      EXT="go"
      ;;
    javascript|js)
      EXT="js"
      ;;
    python|py)
      EXT="py"
      ;;
  esac
}

function PLATFORM_MAPPING {
  case $1 in
    b|baekjoon)
      PLATFORM="baekjoon"
      ;;
    p|programmers)
      PLATFORM="programmers"
      ;;
    l|leetcode)
      PLATFORM="leetcode"
      ;;
  esac
}

function printHelp {
  echo "Usage: algorithm [command] [platform] [options]"
  echo ""
  echo " Commands: create, show, commit, help"
  echo ""
  echo " Platforms: baekjoon, leetcode, programmers, template"
  echo ""
  echo " Options:"
  echo -e "  -l, --lang, --language Specify target language"
  echo -e "  -h, --help \t\t Show help message"
  echo ""
  echo "  options for create:"
  echo -e "  -no, --number \t Specify problem number"
  echo -e "  -n, --name \t\t Specify problem name"
  echo -e "  -u, --url \t\t Specify problem url"
  echo -e "  -d, --date \t\t Specify file creation date (default: today's date)"
}

function printConfig {
  echo "MODE=${MODE}"
  echo "LANG=${LANG}"
  echo "EXT=${EXT}"
  echo "PLATFORM=${PLATFORM}"
  echo "PROBLEM_NUMBER=${PROBLEM_NUMBER}"
  echo "PROBLEM_NAME=${PROBLEM_NAME}"
  echo "PROBLEM_URL=${PROBLEM_URL}"
  echo "DATE=${DATE}"
  echo ""
}

function checkLangSupport {
  lang=$LANG
  LANGUAGE_MAPPING $lang
  if [ -z $EXT ]; then
    echo "Error: Language ${lang} is not supported!"
    exit 1
  fi
}

function createFile {
  while [[ $# -gt 0 ]]; do
    case $1 in
      -no|--number)
        PROBLEM_NUMBER=$2
        shift 2
        ;;
      -n|--name)
        PROBLEM_NAME=$2
        shift 2
        ;;
      -u|--url)
        PROBLEM_URL=$2
        shift 2
        ;;
      -d|--date)
        DATE=$2
        shift 2
        ;;
      *)
        echo "Error: unknown options ${1}"
        echo ""
        printHelp
        exit 1
        ;;
    esac
  done

  printConfig

  scriptPath=$(dirname $0)
  platformPath="${scriptPath}/${PLATFORM}"
  templateDir="${scriptPath}/templates"
  templateFilename="${PLATFORM}.${EXT}"
  outFilePath="${platformPath}/${PROBLEM_NUMBER}. ${PROBLEM_NAME}/solution.${EXT}"

  if [ ! -d $templateDir ]; then
    echo "Error: Directory for templates is not exist."
    exit 1
  fi

  if [ ! -d $platformPath ]; then
    echo "Info: Directory for platform $PLATFORM is not exist. Creating $platformPath"
    mkdir -p $platformPath
  fi

  if [ ! -f "${templateDir}/${templateFilename}" ]; then
    echo "Error: Template does not exist for platform $PLATFORM language $LANG in $templateFilename"
    exit 1
  fi

  mkdir -p "${platformPath}/${PROBLEM_NUMBER}. ${PROBLEM_NAME}"
  sed -e "s|number:|number: ${PROBLEM_NUMBER}|" \
      -e "s|name:|name: ${PROBLEM_NAME}|" \
      -e "s|https://leetcode.com/problems/|${PROBLEM_URL}|" \
      "${templateDir}/${templateFilename}" > "${outFilePath}"

  echo "Successfully created solution file at ${outFilePath}"
}

function showAlgorithm {
  echo "Warning: show command not implemented yet."
}

if [[ $1 = "create" ]]; then
  MODE="create"
elif [[ $1 = "show" ]]; then
  MODE="show"
elif [ $1 = "help" ] || [ $1 = "-h" ]; then
  printHelp
  exit 0
else
  echo "Error: Unknown command $1"
  echo ""
  printHelp
  exit 1
fi

shift

if [ ! -z $1 ]; then
  PLATFORM_MAPPING $1
  if [ -z $PLATFORM ]; then
    echo "Error: Platform $1 is not supported!"
    echo ""
    printHelp
  fi
fi

shift

# Parse options for command
while [[ $# -gt 0 ]]; do
  parseDone=false
  case $1 in
    -l|--lang|--language)
      LANG=$2
      checkLangSupport
      shift 2
      ;;
    -h|--help)
      printHelp
      shift
      ;;
    *)
      parseDone=true
      ;;
  esac
  if [ $parseDone ]; then
    break
  fi
done

if [ $MODE = "create" ]; then
  createFile "$@"
elif [ $MODE = "show" ]; then
  showAlgorithm "$@"
fi