#!/bin/bash

set -e

BASEDIR=`dirname $0`

if [ -f $BASEDIR/config.sh ]; then
    . $BASEDIR/config.sh
fi

if [ -z "$POSTS_DIR" ]
then
  echo "POSTS_DIR environment variable is unset." > /dev/stderr
  exit 2
fi

function usage {
  echo -e "Usage: $0 [OPTIONS] <post title>
Options:
  -h\t\tshow this help
  -d DATE\tuse DATE instead of today's date
  -a AUTHOR\tuse AUTHOR instead of env var \$AUTHOR
  -t TAG\tadd TAG to the taglist (can be used multiple times or contain comma-separated list)
  -e\t\topen new post in \$EDITOR"
}

function filename {
  local unsafe_name="$1"
  echo $unsafe_name | iconv -t ascii//TRANSLIT | tr '[:upper:]' '[:lower:]' | tr -s '[:punct:] ' '-' | sed 's/-*$//g;s/^-*//g'
}

DATE=$(date +%Y-%m-%d)
TAGLIST=''
edit=0

while getopts "hd:a:t:e" option
do
  case $option in
    h)
      usage
      exit
      ;;
    d)
      DATE=$(date +%Y-%m-%d "$OPTARG")
      ;;
    a)
      AUTHOR="$OPTARG"
      ;;
    t)
      if [ -z $TAGLIST ]
      then
        TAGLIST="$OPTARG"
      else
        TAGLIST="$TAGLIST,$OPTARG"
      fi
      ;;
    e)
      edit=1
      ;;
    *)
      echo "Use $0 -h to show help" >&2
      exit 1
      ;;
  esac
done

shift $((OPTIND-1))

TITLE="$1"
TEMPLATE=post

FILENAME="$(filename "$TITLE").md"

export TITLE AUTHOR DATE TAGLIST TEMPLATE

cat $BASEDIR/post.tpl | envsubst > $BASEDIR/$POSTS_DIR/$FILENAME

if [ $edit == 1 ]
then
  $EDITOR $BASEDIR/$POSTS_DIR/$FILENAME
else
  echo $FILENAME
fi