#!/usr/bin/env bash

VERSION="0.4.0"
REMOTE=git://github.com/visionmedia/mad-pages.git
REMOTE_MAD=git://github.com/visionmedia/mad.git
CONFIG=$(dirname $0)/../etc/mad.conf
MAD_CONFIG=${MAD_CONFIG:-$CONFIG}

#
# List all <pages>
#

list_pages() {
  IFS=":"
  local paths="$MAD_PATH:/usr/local/share/mad:/usr/share/mad"

  echo
  printf "  \033[1mmad pages:\033[0m\n"
  echo
  for path in $paths; do
    test ! -z $path \
      && test -d $path \
      && find $path -type f -print0 \
      | xargs -0 basename -a \
      | grep -iv 'readme*' \
      | grep '.md$' \
      | perl -pe 's|^(.*)\.md$|    \1|;'
  done
  echo
}

#
# Display <page> with lookup via MAD_PATH.
#

display() {
  IFS=":"
  local page=$1
  local paths=".:$MAD_PATH:$(dirname $0)/../share/mad:/usr/share/mad"

  for path in $paths; do
    local file=$path/$page
    local ext=$path/$page.md
    [[ -f "$file" ]] && display_file $file
    [[ -f "$ext" ]]  && display_file $ext
  done

  echo
  echo "  Failed to locate '$page'"
  echo
  echo "    MAD_PATH=\"$paths\""
  echo
  exit 1
}

#
# Get <prop> from config.
#

get() {
  grep "$1" "$MAD_CONFIG" | awk '{ print $2 }'
}

#
# Display from stdin.
#

display_from_stdin() {
  display_file <(cat)
}

#
# Display <file>
#

display_file() {
  local heading=$(get heading)
  local code=$(get code)
  local strong=$(get strong)
  local em=$(get em)

  < "$1" perl -pe "
      s|^#+ *(.+)|\e[$heading\1\e[0m|g; \
      s|\`(.+?)\`|\e[$code\1\e[0m|g; \
      s|\*\*(.+?)\*\*|\e[$strong\1\e[0m|g; \
      s|__(.+?)__|\e[$strong\1\e[0m|g; \
      s|\*(.+?)\*|\e[$em\1\e[0m|g; \
      s|_(.+?)_|\e[$em\1\e[0m|g; \
      s|    (.+)|    \e[$code\1\e[0m|g; \
      s|<(.+?)>||g; \
      s|^|  |;" \
    | less -R
  exit
}

#
# Display the usage for mad(1).
#

display_mad_usage() {
  display_file $(dirname $0)/../share/mad/mad.md
  exit
}

#
# Install remote manuals.
#

install_all_remote() {
  local path=$(dirname $0)/../share/mad
  echo
  echo "  ... cloning repo"
  cd /tmp && rm -fr mad-pages
  git clone --depth 1 $REMOTE mad-pages
  cd mad-pages
  for page in *.md; do
    echo "  ... installing $page"
    cp -f $page $path/$page
  done
  echo "  ... complete"
  echo
}

#
# Install mad(1) again.
#

install_mad() {
  echo
  echo "  ... cloning repo"
  cd /tmp && rm -fr mad
  git clone --depth 1 $REMOTE_MAD mad
  cd mad && make install
  echo "  ... updated to $(mad --version)"
  echo
}

# file required

[[ -z "$1" ]] && display_mad_usage

# parse args

case $1 in
  -v|--version)
    echo $VERSION
    ;;
  -h|--help|help)
    display_mad_usage
    ;;
  -u|--update|update)
    install_all_remote
    ;;
  -U|--update-self|update-self)
    install_mad
    ;;
  -l|--list|ls|list)
    list_pages
    ;;
  -)
    display_from_stdin
    ;;
  *)
    display $1
    ;;
esac