#!/bin/bash
########################################
#       Beats Ye-Bash4 Framework       #
#   http://github.com/Beats/ye-bash4   #
########################################

[ ${BASH_VERSINFO[0]} -lt 4 ] && >&2 echo "Requires Bash v4" && exit 2

[ "$0" != "$BASH_SOURCE" ]
YE_BASH4_BUILDER=$?

YE_BASH4_SCRIPT_FILE=$(cd `dirname "$0"` && pwd)/`basename "$0"`
YE_BASH4_SCRIPT_NAME=${YE_BASH4_SCRIPT_FILE##*/}
YE_BASH4_SCRIPT_HOME=${YE_BASH4_SCRIPT_FILE%/*}
YE_BASH4_SCRIPT_VERSION="0.1"

##
# Constants
##
declare -r YE_BASH4_VERSION="0.1"

declare -r YE_BASH4_TYPE_F=-1
declare -r YE_BASH4_TYPE_C=-2
declare -r YE_BASH4_TYPE_A=1
declare -r YE_BASH4_TYPE_P=2

##
# Parameters
##
declare -A YE_BASH4_PARAMETER
declare -A YE_BASH4_PARAMETER_TYPE

declare -A YE_BASH4_OPTIONS
declare -A YE_BASH4_OPTION_USAGE

declare -a YE_BASH4_COMPONENT_C
declare -a YE_BASH4_COMPONENT_F
declare -a YE_BASH4_COMPONENT_P

declare -a YE_BASH4_ARGS
YE_BASH4_COMMAND=
YE_BASH4_DEFAULT="ye_bash4_usage"

##
# Utilities
##
ye_bash4_is_function() {
  declare -f "$1" > /dev/null;
  return $((1 -$?))
}

ye_bash4_parse_register_args() {
  local arg
  for arg in "$@"; do
    case "$arg" in
      --*) __optL="$arg";;
      -*) __optS="$arg";;
      *) __text="$arg";;
    esac
  done
}

ye_bash4_register_C() {
  local __name="$1"
  local __optS=""
  local __optL=""
  local __text=""
  shift;
  ye_bash4_parse_register_args "$@"
  ye_bash4_register "$YE_BASH4_TYPE_C" "$__name" "$__optS" "$__optL" "$__text"
}

ye_bash4_register_F() {
  local __name="$1"
  local __optS=""
  local __optL=""
  local __text=""
  shift;
  ye_bash4_parse_register_args "$@"
  ye_bash4_register "$YE_BASH4_TYPE_F" "$__name" "$__optS" "$__optL" "$__text"
}

ye_bash4_register_P() {
  local __name="$1"
  local __optS=""
  local __optL=""
  local __text=""
  shift;
  ye_bash4_parse_register_args "$@"
  ye_bash4_register "$YE_BASH4_TYPE_P" "$__name" "$__optS" "$__optL" "$__text"
}

ye_bash4_register() {
  local __type="$1"
  local __name="$2"
  local __optS="$3"
  local __optL="$4"
  local __text="$5"

  ye_bash4_normalize_options() {
    local __optS="$1"
    local __optL="$2"
    local __delimiter="$3"
    if [ -z "$__delimiter" ]; then
      __delimiter="|"
    fi

      if [ -z "$__optS" ]; then
      printf "%s" "$__optL"
    elif [ -z "$__optL" ]; then
      printf "%s" "$__optS"
    else
      printf "%s" "$__optS$__delimiter$__optL"
    fi
  }

  ye_bash4_format_usage() {
    local __optS="$1"
    local __optL="$2"
    local __text="$3"
    local __opts=`ye_bash4_normalize_options "$__optS" "$__optL" ", "`
    echo -e "  $__opts\n      $__text\n"
  }

  if [ -z "$__optS" -a -z "$__optL" ]; then
    >&2 echo "Invalid option registration for: $__name"
    exit 1;
  fi

  case "$__type" in
    "$YE_BASH4_TYPE_C")
      YE_BASH4_COMPONENT_C+=($__name)
    ;;
    "$YE_BASH4_TYPE_F")
      YE_BASH4_COMPONENT_F+=($__name)
    ;;
    "$YE_BASH4_TYPE_P")
      YE_BASH4_COMPONENT_P+=($__name)
    ;;
  esac

  YE_BASH4_PARAMETER[$__name]="`ye_bash4_normalize_options "$__optS" "$__optL"`"
  YE_BASH4_PARAMETER_TYPE[$__name]=$__type
  YE_BASH4_OPTION_USAGE[$__name]="`ye_bash4_format_usage "$__optS" "$__optL" "$__text"`
"
  unset -f ye_bash4_normalize_options
}

###############################
#  Ye-Bash4 Framework Engine  #
###############################



##
# Processes the registered components
##
ye_bash4_registration_processor() {

  ye_bash4_register_defaults() {
    ##
    # Flags
    ##
    ye_bash4_register $YE_BASH4_TYPE_F "YE_BASH4_VERBOSE" "-v" "--verbose" "Explain what is being done"
    YE_BASH4_VERBOSE=0

    ye_bash4_register $YE_BASH4_TYPE_F "YE_BASH4_DEBUG" "" "--debug" "Display debugging information"
    YE_BASH4_DEBUG=0

    ##
    # Commands
    ##
    ye_bash4_register $YE_BASH4_TYPE_C "ye_bash4_version" "" "--version" "Display the script version"
    ye_bash4_is_function "ye_bash4_version"
    if [ $? -eq 0 ]; then
      ye_bash4_version() {
        echo "$YE_BASH4_SCRIPT_NAME v$YE_BASH4_SCRIPT_VERSION"
        echo
      }
    fi

    ye_bash4_register $YE_BASH4_TYPE_C "ye_bash4_usage" "-h" "--help" "Display this usage text"
    ye_bash4_is_function "ye_bash4_usage"
    if [ $? -eq 0 ]; then
      ye_bash4_usage() {
        local __name=
        echo "Usage: $YE_BASH4_SCRIPT_NAME"
        echo "Options:"
        for __name in "${YE_BASH4_COMPONENT_P[@]}"; do
          echo "${YE_BASH4_OPTION_USAGE[$__name]}"
        done
        for __name in "${YE_BASH4_COMPONENT_F[@]}"; do
          echo "${YE_BASH4_OPTION_USAGE[$__name]}"
        done
        for __name in "${YE_BASH4_COMPONENT_C[@]}"; do
          echo "${YE_BASH4_OPTION_USAGE[$__name]}"
        done
      }
    fi

    ye_bash4_is_function "ye_bash4_debug"
    if [ $? -eq 0 ]; then
      ye_bash4_debug() {
        local __i=0
        local __name=
        echo "$YE_BASH4_SCRIPT_NAME: $YE_BASH4_SCRIPT_VERSION"
        echo "Beats Ye-Bash4: $YE_BASH4_VERSION"
        echo "Command: $YE_BASH4_COMMAND"
        echo "Flags:"
        for __name in "${YE_BASH4_COMPONENT_F[@]}"; do
          echo -n "  $__name:"; eval echo \$$__name
        done
        echo "Parameters:"
        for __name in "${YE_BASH4_COMPONENT_P[@]}"; do
          echo -n "  $__name:"; eval echo \$$__name
        done
        echo "Arguments:"
        for __name in "${YE_BASH4_ARGS[@]}"; do
          echo "  YE_BASH_ARGS[$__i]:$__name"; ((__i++));
        done
        if [ $YE_BASH4_VERBOSE -ne 0 ]; then
          echo "Script:"
          echo "  Name: $YE_BASH4_SCRIPT_NAME"
          echo "  Home: $YE_BASH4_SCRIPT_HOME"
          echo "  File: $YE_BASH4_SCRIPT_FILE"
        fi;
      }
    fi

    if [ "$YE_BASH4_BUILDER" -eq 0 ]; then
      unset -f ye_bash4_is_function ye_bash4_format_usage
      unset -f ye_bash4_parse_register_args ye_bash4_register ye_bash4_register_C ye_bash4_register_F ye_bash4_register_P
    fi
  }

  ye_bash4_register_defaults
  unset -f ye_bash4_register_defaults

  ye_bash4_component_builder() {

    ye_bash4_join() {
      local IFS="$1"; shift; echo "$*";
    }

    ye_bash4_getopt_option_builder() {
      local __component=$1
      local __opts=$2
      local __handler=$3
      local __modifier=$4


      local __option=
      local __options=(${__opts//\|/ })

      for __option in "${__options[@]}"; do
        YE_BASH4_OPTIONS[$__option]="$__component|$__handler"
        case "$__option" in
          -?)
            YE_BASH4_OPTS_S+=("${__option:1}$__modifier")
          ;;
          --*)
            YE_BASH4_OPTS_L+=("${__option:2}$__modifier")
          ;;
        esac
      done
    }

    ye_bash4_component_processor() {
      local __component=$1
      local __opts=$2
      local __type=$3
      local __handler=
      local __modifier=""

      case "$__type" in
        "$YE_BASH4_TYPE_C")
          __handler="ye_bash4_action"
          __modifier=""
        ;;
        "$YE_BASH4_TYPE_F")
          __handler="ye_bash4_flag"
          __modifier=""
        ;;
        "$YE_BASH4_TYPE_P")
          __handler="ye_bash4_parameter"
          __modifier=":"
        ;;
      esac

      ye_bash4_getopt_option_builder "$__component" "$__opts" "$__handler" "$__modifier"
    }

    local __key=
    for __key in "${!YE_BASH4_PARAMETER[@]}"; do
      ye_bash4_component_processor "$__key" "${YE_BASH4_PARAMETER[$__key]}" "${YE_BASH4_PARAMETER_TYPE[$__key]}"
    done

    YE_BASH4_OPTS_S=`ye_bash4_join "" "${YE_BASH4_OPTS_S[@]}"`
    YE_BASH4_OPTS_L=`ye_bash4_join , "${YE_BASH4_OPTS_L[@]}"`

    unset -f ye_bash4_join ye_bash4_getopt_option_builder ye_bash4_component_processor
    unset -v YE_BASH4_PARAMETER YE_BASH4_PARAMETER_TYPE
  }

  local YE_BASH4_OPTS_L=()
  local YE_BASH4_OPTS_S=()

  ye_bash4_component_builder

  YE_BASH4_GETOPT="getopt -o "$YE_BASH4_OPTS_S" -l "$YE_BASH4_OPTS_L" -n "$YE_BASH4_SCRIPT_NAME" --"

  unset -f ye_bash4_component_builder
  unset -v YE_BASH4_OPTS_L YE_BASH4_OPTS_S
}

##
# Parses the user provided input
#
ye_bash4_input_parser() {

  YE_BASH4_GETOPT=`$YE_BASH4_GETOPT "$@"`
  if [ $? -ne 0 ]; then
    ye_bash4_usage
    exit 1
  fi

  ye_bash4_input_processor() {
    eval set -- "$YE_BASH4_GETOPT"

    ye_bash4_action() {
      if [ -z "$YE_BASH4_COMMAND" ]; then
        YE_BASH4_COMMAND="$1"
        return 1
      else
        YE_BASH4_COMMAND="ye_bash4_usage"
        return 0
      fi
    }

    ye_bash4_parameter() {
      local __name=$1
      if [ ! -z "$2" ]; then
        eval "$__name=\"$2\""
      fi
      return 2
    }

    ye_bash4_flag() {
      local __param=$1
      eval $__param=$((1 - $__param))
      return 1
    }

    ye_bash4_option_handler() {
      local __option="$1"
      local __return=0

      local __pattern=${YE_BASH4_OPTIONS["$__option"]}
      local __options=(${__pattern//\|/ })
      local __component=${__options[0]}
      local __handler=${__options[1]}

      $__handler $__component "$2"
      __return=$?
      unset YE_BASH4_OPTIONS[$__option]

      return $__return
    }

    local __loop=
    while true; do
      if [[ "$1" == "--" ]]; then
        shift
        break
      fi
      ye_bash4_option_handler "$1" "$2"
      __loop=$?
      if [ $__loop -gt 0 ]; then
        shift $__loop
      elif [ $__loop -eq 0 ]; then
        break
      fi
    done

    for __loop do
      YE_BASH4_ARGS+=("$__loop")
    done

    unset -f ye_bash4_action ye_bash4_flag ye_bash4_parameter ye_bash4_option_handler

    if [ -z "$YE_BASH4_COMMAND" ]; then
      YE_BASH4_COMMAND="$YE_BASH4_DEFAULT"
    fi
  }

  ye_bash4_input_processor
  unset -f ye_bash4_input_processor

  if [ $YE_BASH4_DEBUG -ne 0 ]; then
    ye_bash4_debug
    exit 0
  fi
}

##
# Interpreter
##
ye_bash4_interpreter() {
  local YE_BASH4_GETOPT
  ye_bash4_registration_processor
  if [ "$YE_BASH4_BUILDER" -eq 0 ]; then
    unset -f ye_bash4_registration_processor
  fi

  unset -f ye_bash4_interpreter

  ye_bash4_executor "$@"
}

##
# Executor
##
ye_bash4_executor() {
  ye_bash4_input_parser "$@"
  unset -v YE_BASH4_GETOPT

  if [ "$YE_BASH4_BUILDER" -eq 0 ]; then
    unset -f ye_bash4_input_parser
    unset -v YE_BASH4_OPTIONS
    unset -f ye_bash4_interpreter ye_bash4_executor
  fi

  $YE_BASH4_COMMAND

  ye_bash4_collect_garbage() {
    local __name
    for __name in "${YE_BASH4_COMPONENT_P[@]}"; do
      unset -v "$__name"
    done
    for __name in "${YE_BASH4_COMPONENT_F[@]}"; do
      unset -v "$__name"
    done
    for __name in "${YE_BASH4_COMPONENT_C[@]}"; do
      unset -f "$__name"
    done
  }

  ye_bash4_collect_garbage
  unset -f ye_bash4_collect_garbage

  unset -f ye_bash4_usage ye_bash4_debug ye_bash4_version
  unset -v YE_BASH4_OPTION_USAGE

  unset -v YE_BASH4_COMMAND YE_BASH4_ARGS YE_BASH4_DEBUG YE_BASH4_VERBOSE
  unset -v YE_BASH4_SCRIPT_FILE YE_BASH4_SCRIPT_NAME YE_BASH4_SCRIPT_HOME YE_BASH4_SCRIPT_VERSION
  unset -v YE_BASH4_COMPONENT_C YE_BASH4_COMPONENT_F YE_BASH4_COMPONENT_P
}

if [ "$YE_BASH4_BUILDER" -ne 0 ]; then

  ye_bash4_confirm() {
    if [ "${2:-0}" -ne 0 ]; then
      return 0
    fi
    read -r -p "${1:-Are you sure?} [y/N] " response
    case $response in
        [yY][eE][sS]|[yY])
            true
            ;;
        *)
            false
            ;;
    esac
  }

  ye_bash4_target_comment() {
    local __target="$1"
    sed -i "/$2/ s:^:#yb4#:" "$__target"
  }

  ye_bash4_target_reset() {
    local __target="$1"
    local __source="$2"

    if [ ! -z "$__source" ]; then
      cp $__target $__source
      __target="$__source"
    fi

    sed -i '/^#yb4##yb4##yb4##yb4##yb4##yb4#$/,$d' $__target
    sed -i 's/#yb4#//g' $__target
    sed -i -e :a -e '/^\n*$/{$d;N;ba' -e '}' $__target
  }

  ye_bash4_target_build() {
    local __target="${YE_BASH4_ARGS[1]}"
    local __source="${YE_BASH4_ARGS[0]}"

    if [ ! -f "$__source" ]; then
      >&2 echo "The source file doesn't exist: $__source"
      exit 2;
    fi
    if [ ! -r "$__source" ]; then
      >&2 echo "The source file is not readable: $__source"
      exit 2;
    fi
    __source=$(cd `dirname "$__source"` && pwd)/`basename "$__source"`
    if [ "$YE_BASH4_SCRIPT_FILE" == "$__source" ]; then
      >&2 echo "Are you really that crazy, trying to build a file from the framework source: $__source"
      exit 2;
    fi
    if [ -f "$__target" ]; then
      __target=$(cd `dirname "$__target"` && pwd)/`basename "$__target"`
      if [ "$YE_BASH4_SCRIPT_FILE" == "$__target" ]; then
        >&2 echo "Are you really that crazy, trying to overwrite the framework: $__target"
        exit 2;
      fi
      ye_bash4_confirm "Are your sure you want to overwrite the file: $__target?" $YE_BASH4_AUTOCONFIRM
      if [ "$?" -ne 0 ]; then
        exit 0;
      fi
    else
      touch "$__target" > /dev/null 2>&1
      if [ "$?" -ne 0 ]; then
        >&2 echo "The target file can't be created: $__target"
        exit 2;
      fi
      __target=$(cd `dirname "$__target"` && pwd)/`basename "$__target"`
    fi

    echo "Building '$__target' script from '$__source'"

    cp $__source $__target

    ye_bash4_target_escape() {
      local __target="$1"
      local __step="$2"

      case $__step in
        0)
          ye_bash4_target_comment $__target '^\s*ye_bash4_interpreter.*$'
          ye_bash4_target_comment $__target '^\s*\(source\|\.\)\s.*ye-bash4\.sh.*$'
        ;;
        1)
          ye_bash4_target_comment $__target '^\s*ye_bash4_register.*$'
          ye_bash4_target_comment $__target '^\s*YE_BASH4_SCRIPT_VERSION.*$'
        ;;
      esac
    }

    ye_bash4_target_escape $__target 0

    unset -v YE_BASH4_COMPONENT_C YE_BASH4_COMPONENT_F YE_BASH4_COMPONENT_P
    unset -v YE_BASH4_PARAMETER YE_BASH4_PARAMETER_TYPE
    unset -v YE_BASH4_OPTION_USAGE YE_BASH4_OPTIONS

    declare -A YE_BASH4_OPTIONS
    declare -A YE_BASH4_OPTION_USAGE

    declare -A YE_BASH4_PARAMETER
    declare -A YE_BASH4_PARAMETER_TYPE

    declare -a YE_BASH4_COMPONENT_C
    declare -a YE_BASH4_COMPONENT_F
    declare -a YE_BASH4_COMPONENT_P

    local YE_BASH4_GETOPT=

    source $__target

    YE_BASH4_SCRIPT_FILE=$__target
    YE_BASH4_SCRIPT_NAME=${YE_BASH4_SCRIPT_FILE##*/}

    ye_bash4_registration_processor

    ye_bash4_target_escape $__target 1

    unset -f ye_bash4_target_escape

    declare -a YE_BASH4_DEFAULT_COMMANDS
    ye_bash4_is_overridden() {
      local __command="$2"
      local __count=`grep -Pc "^(\s*)(function)?(\s*)?$__command\s*(\(\))?\s*{" $1`
      if [[ $__count -eq 0 ]]; then
        YE_BASH4_DEFAULT_COMMANDS+=("$__command")
      fi
      return $__count
    }
    ye_bash4_is_overridden "$__target" 'ye_bash4_usage'
    ye_bash4_is_overridden "$__target" 'ye_bash4_debug'
    ye_bash4_is_overridden "$__target" 'ye_bash4_version'
    unset -f ye_bash4_is_overridden

    echo >> $__target
    echo >> $__target
    echo "#yb4##yb4##yb4##yb4##yb4##yb4##yb4##yb4#" >> $__target
    echo "########################################" >> $__target
    echo "#       Beats Ye-Bash4 Framework       #" >> $__target
    echo "#   http://github.com/Beats/ye-bash4   #" >> $__target
    echo "########################################" >> $__target
    echo "#yb4##yb4##yb4##yb4##yb4##yb4##yb4##yb4#" >> $__target

    echo "YE_BASH4_BUILDER=0" >> $__target
    echo >> $__target

    echo 'YE_BASH4_SCRIPT_FILE=$(cd `dirname "$0"` && pwd)/`basename "$0"`' >> $__target
    echo 'YE_BASH4_SCRIPT_NAME=${YE_BASH4_SCRIPT_FILE##*/}' >> $__target
    echo 'YE_BASH4_SCRIPT_HOME=${YE_BASH4_SCRIPT_FILE%/*}' >> $__target
    set | grep ^YE_BASH4_SCRIPT_VERSION >> $__target
    echo >> $__target

    echo "##" >> $__target
    echo "# Constants" >> $__target
    echo "##" >> $__target
    echo "declare -r YE_BASH4_VERSION='$YE_BASH4_VERSION'" >> $__target
    echo >> $__target
    echo "declare -r YE_BASH4_TYPE_F=$YE_BASH4_TYPE_F" >> $__target
    echo "declare -r YE_BASH4_TYPE_C=$YE_BASH4_TYPE_C" >> $__target
    echo "declare -r YE_BASH4_TYPE_A=$YE_BASH4_TYPE_A" >> $__target
    echo "declare -r YE_BASH4_TYPE_P=$YE_BASH4_TYPE_P" >> $__target
    echo >> $__target

    echo "##" >> $__target
    echo "# Parameters" >> $__target
    echo "##" >> $__target
    echo "declare -A YE_BASH4_OPTIONS" >> $__target
    echo "declare -A YE_BASH4_OPTION_USAGE" >> $__target
    echo >> $__target
    echo "declare -A YE_BASH4_COMPONENT_C" >> $__target
    echo "declare -A YE_BASH4_COMPONENT_F" >> $__target
    echo "declare -A YE_BASH4_COMPONENT_P" >> $__target
    echo >> $__target
    echo "declare -a YE_BASH4_ARGS" >> $__target
    echo "YE_BASH4_COMMAND=" >> $__target
    echo >> $__target

    set | grep ^YE_BASH4_COMPONENT_C >> $__target
    set | grep ^YE_BASH4_COMPONENT_F >> $__target
    set | grep ^YE_BASH4_COMPONENT_P >> $__target
    echo >> $__target

    echo "##" >> $__target
    echo "# Flags" >> $__target
    echo "##" >> $__target
    echo "YE_BASH4_VERBOSE=0" >> $__target
    echo "YE_BASH4_DEBUG=0" >> $__target
    echo >> $__target

    set | grep ^YE_BASH4_GETOPT >> $__target
    set | grep ^YE_BASH4_OPTIONS >> $__target
    set | grep -Pzo "(?s)^(\s*)YE_BASH4_OPTION_USAGE=\(.*?\" \)$" >> $__target
    echo >> $__target

    echo "##" >> $__target
    echo "# Commands" >> $__target
    echo "##" >> $__target

    local __name
    for __name in "${YE_BASH4_DEFAULT_COMMANDS[@]}"; do
      set | grep -Pzo "(?s)^(\s*)$__name\s*\(\).*?{.*?^\1}" >> $__target
      echo >> $__target
    done

    echo "##" >> $__target
    echo "# Engine" >> $__target
    echo "##" >> $__target

    set | grep -Pzo "(?s)^(\s*)ye_bash4_input_processor *\(\).*?{.*?^\1}" >> $__target
    echo >> $__target
    set | grep -Pzo "(?s)^(\s*)ye_bash4_input_parser *\(\).*?{.*?^\1}" >> $__target
    echo >> $__target
    set | grep -Pzo "(?s)^(\s*)ye_bash4_executor *\(\).*?{.*?^\1}" >> $__target
    echo >> $__target

    echo 'ye_bash4_executor "$@"' >> $__target

    if [ "$YE_BASH4_CLEAN" -ne 0 ]; then
      ye_bash4_confirm "Are you sure you wan't to build a clean script. You wont be able to regenerate the original source?" $YE_BASH4_AUTOCONFIRM
      if [ "$?" -eq 0 ]; then
        ye_bash4_target_purge() {
          local __target="$1"
          sed -i '/^#yb4#/d' $__target
        }

        ye_bash4_target_purge $__target
        unset -f ye_bash4_target_purge
      fi
    fi

    echo "Done"
  }

  YE_BASH4_AUTOCONFIRM=0
  ye_bash4_register_F "YE_BASH4_AUTOCONFIRM" "-y" "Assume Yes to all queries and do not prompt"

  YE_BASH4_CLEAN=0
  ye_bash4_register_F "YE_BASH4_CLEAN" "--clean" "Build a clean (irreversible) script"

  ye_bash4_register_C "ye_bash4_target_build" "-b" "--build" "Build a standalone script based on the given source"
  ye_bash4_register_C "ye_bash4_target_reset" "-r" "--reset" "Restore the built script to source"

  YE_BASH4_DEFAULT="ye_bash4_target_build"

  ye_bash4_interpreter "$@"

fi