fn conf_enable_flip {
    extensions=(pdf ps)
    prev_res=150
    thumb_res=15

    pages_root=`{pwd}^'/_werc/pages'
    mkdir -p $pages_root
    base_path=`{basename -d $conf_wd}

    conf_enable_app flip
}

fn flip_init {
    # this could cause problems with filenames matching [0-9]+
    pages_doc=`{echo $local_path | sed 's|/[0-9]+(-[0-9]*)?/?$||'}
    if (test -f $werc_root^'/'^$pages_doc^'.'^$extensions){
	name=`{basename $pages_doc}
	pages_doc_root=$pages_root^'/'^$name
	pages_file=`{ls $werc_root^'/'^$pages_doc^'.'^$extensions}
	if (! test $pages_doc_root -nt $pages_file){
		mkdir -p $pages_doc_root'/thumbs/'
		pages2pngs $pages_file $pages_doc_root'/thumbs' 15
		pages2pngs $pages_file $pages_doc_root 90
	}
	page_num=`{basename $req_path}
	page_tot=`{ls $pages_doc_root^/*.png |wc -l}
	if (echo $page_num | grep -s '^[0-9]+-[0-9]*$'){
		page_num=`{basename $req_path | sed 's/-[0-9]*//'}
		handler_body_main=pageindex
	}
	if not if (~ $pages_doc $local_path){
		page_num=1
		handler_body_main=pageindex
	}
	if not
		handler_body_main=pageprev
	if (test $page_num -gt $page_tot)
		handler_body_main=()
    }
}

fn pages2pngs {
	gs -q -dNOPAUSE -dBATCH -s'DEVICE=png16m' -r^$3 -d'TextAlphaBits=4' -d'GraphicsAlphaBits=4' -s'OutputFile='^$2^'/%d.png' $1 
}

fn pagelist {
	ls -p $pages_doc_root | sed 's/\.png//p;d' | sort -n
}

# Usage: paginate number step total 'string %d %s'
fn paginate {
	awk '
	BEGIN {
		n='$1';
		s='$2'; s3=int(s/3);
		a=int(n/s3)*s3-s3;
		if(a<1) a=1;
		if(n>a+2*s3) a+=s3;
		w=a+s;
		t='$3';
		str="'$4'";
	}
	NR==a && NR>1 {
		printf(str, 1, "first");
		if(n-s > 0)
			printf(str, n-s, "(-" s ")");
		print "|";
	}
	NR>=a && NR<w {
		printf(str, NR, NR);
	}
	NR==w && NR<=t {
		print "|";
		if(n+s <= t)
			printf(str, n+s, "(+" s ")");
		printf(str, t, "last");
	}'
}

fn pagethumbs {
	for (p in `{ls -p $pages_doc_root | sed 's/\.png//p;d' | sort -n}){
		img='<img src="'$base_path'/_werc/pages/'$name'/thumbs/'$p'.png">'
		echo '<a href="'$base_path'/'$name'/'$p'">'$img'</a>'
	}
}

fn pagenav {
	ls -p $pages_doc_root^/*.png | sort -n | awk '
	   /^'^`{basename $req_path}^'\.png/{
	      if(sub("\.png$", "", p))
	      	print "<a title=\"prev\" href=\"" p "\">'$1'</a>";
	      print "<a title=\"all\" href=\"" int('$page_num'/50)*50+1 "-\">'$3'</a>";
	      getline;
	      if(sub("\.png$", "", $0))
	      	print "<a title=\"next\" href=\"" $0 "\">'$2'</a>";
	      exit;
	   }
	   {p = $0;}'
}

fn pageindex {
	tpl_handler apps/flip/pageindex.tpl
}

fn pageprev {
	tpl_handler apps/flip/pageprev.tpl
}