#!/usr/bin/perl -w

use Tie::File;	
use strict;

###
### This is a complete, self-contained dummy script to 
### test the insert functionality of this sub...
###

##########################################################################
###
### These vars should be changed to demonstrate different behaviours
###
my $thread = "208";	  # is the thread identifier
my $msg_id = "211";	  # is this message's unique number
my $parent = "208_208"; # is the message_id of the parent post

## To create new top-level post set $thread=$msg_id, $parent is ununsed
## and should be undef

## All replies to given top-level post should carry same $thread value, 
## whereas $msg_id is incremented

## Set $parent to: ($thread . "_" . $msg_id) to make a reply to the 
## post which carries that message_id string in the html comment

## $msg_id should be unique for each post ($msg_id++)
## $thread should be unique for each thread

#########################################################################

###
### These vars are (relatively) static
###
my @threads;				# the array we will use
my $main_threads_file = "threads.html";	# the threads file we will work on
my $link = "<li><!-- message_id=$thread" . "_" . "$msg_id  --><a href=\"http://link_to_post\">dummy link to message $thread - $msg_id</a>";

### Update the main threads file
tie @threads, 'Tie::File', $main_threads_file or syslog('err', "update_threads couldn't open file: $main_threads_file");

if ($thread == $msg_id) {
	# put it right at the top, it's a new thread
	unshift @threads, $link;
} else {
	for my $i (0 .. $#threads) {
		if ($threads[$i] =~ $parent) {
			if ($threads[$i+1] eq "<ul type=\"disc\">") {
				# insert $link after the next element (after the <ul>)
				$threads[$i+1] .= "\n$link";
			}
			else {
				# insert three new lines/records after the parent
				$threads[$i] .= "\n<ul type=\"disc\">\n$link\n</ul>\n";
			}
			last;
				
		}
	}
	
}
untie @threads;