#!/bin/bash
#
# pbrisbin 2010
#
# utilities for managing my website. contains useful
# functions and constants. functions should check their
# input and required constants before running in case
# i eff up their usage in a script sourcing this
#
# when possible args/constants should have sane default
# values (see mk_href as an example)
#
###

# UTILITIES {{{

# standard logger
logger() { echo "$(date +'[ %d %b %Y %H %M ]') :: $(basename $0) :: $*" | tee -a "$log"; }

# standard errorout
errorout() { logger "error: $*"; exit 1; }

# standard help
message() { echo 'dude, an un-overloaded call to message(), really?'; exit 1; }

# }}}

# relative to absolute {{{
#
# usage: rel2abs ./file  rel2abs ~/file  rel2abs file
#
rel2abs() {
  local file="$1" dir

  if [ ! -e "$file" ]; then
    echo "$file"
    return
  fi

  dir="$(dirname "$file")"
  file="$(basename "$file")"

  pushd "${dir:-./}" &>/dev/null || exit 1
  dir="$PWD"
  popd &>/dev/null

  echo "$dir/$file"
}

# }}}

# make href and swap {{{
#
# usage: mk_href /srv/http/pages/something.html here
#
mk_href() {
  local file="${1:-/srv/http/}"
  local link="${2:-$(basename "$file")}"
  local reverse=${reverse:-false}

  local wrappers=('<a href="' '">' '</a>')

  $reverse && file_root='' || page_root=''

  echo "${wrappers[0]}$(swap "$file")${wrappers[1]}$link${wrappers[2]}"
}

# usage: swap /srv/http/something.html  swap -r http://pbrisbin.com/something.html
#
swap() { 
  local reverse=${reverse:-false}

  $reverse && echo "${*//$page_root/$file_root}" || echo "${*//$file_root/$page_root}"
}

# }}}

# list all pages in order of most recently modified {{{
#
# usage: get_pages_by_date
#
#get_pages_by_date() { ls -lt "$pages"/*.html | grep -v -- '->' | awk '{print $NF}'; }

# }}}

# image manipulation {{{
#
# usage: make_size 'half' 50 /image
#
make_size() {
  local name="$1" perc="$2" file="$3"

  case "$file" in
    *.png)  thum="${file/.png/-$name.png}"   ;;
    *.jpg)  thum="${file/.jpg/-$name.jpg}"   ;;
    *.jpeg) thum="${file/.jpeg/-$name.jpeg}" ;;
    *.bmp)  thum="${file/.bmp/-$name.bmp}"   ;;
    *)      return 1                         ;;
  esac

  [[ -e "$thum" ]] && return

  cp "$file" "$thum" && mogrify -resize ${perc}% "$thum"
}

# do a conditional resize of $1
# return basename of resized image
#
# usage: do_resize /image
#
do_resize() {
  local file="$1"
  local width=$(feh -l "$file" | tail -1 | awk '{print $3}')

  # makes thumb and sets var $thum
  if [[ $width -le 1920 ]]; then
    make_size 'half' 50 "$file" || return 1
  elif [[ $width -le 3600 ]]; then
    make_size 'third' 30 "$file" || return 1
  else
    make_size 'thumb' 20 "$file" || return 1
  fi

  echo $(basename "$thum")
}

# }}}
 
# set or check and md5 of a file {{{
#
# usage: check_md5 set /path/to/file  check_md5 get /path/to/file
#
check_md5() {
  local mode="$1"
  local _md5="$(md5sum "$2" | awk '{print $1}')"

  case "$mode" in
    set) md5="$_md5"                               ;;  
    get) [[ "$md5" = "$_md5" ]]                    ;;  
    *)   errorout 'invalid options to check_md5()' ;;
  esac
}

# }}}

# show available functions {{{
show_available() { grep '^# usage:' "$me"; }

# }}}

# constants {{{
me='/home/patrick/.bin/siteutils'

# all site management can log here or
# override this on a per script basis
log='/home/patrick/.logs/siteutils.log'

# file and page paths
srv='/srv/http'
site='http://pbrisbin.com'

# used in swap()
page_root="$site"
file_root="$srv"

# holds all *.html pages
pages="$srv/pages"

# holds all screenshots
shots_dir="$srv/screenshots"

# }}}