<?php

/*
OneLobby
Copyright (C) 2007 Peter Goodman, Geoffrey Goodman

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
*/

//-------------------------------------------------
// Deal with thread, comment and user karma
//-------------------------------------------------

class KarmaController extends k4PageController 
{
	function getPreFilters() 
	{
		return array('request', 'session', 'user', 'debug_pre', 'template');
	}
	
	function getPostFilters() 
	{
		return array('user_post', 'history_post');
	}
	
	function getRoutes() 
	{
		return array(
			'rate' => '/rate/:post_type/:post_id/:rating',
		);
	}
	
	function index(&$reg, &$req, &$resp) 
	{
		
	}
	
	//-------------------------------------------------
	// Rate a thread or a comment.
	//-------------------------------------------------
	
	function rate(&$reg, &$req, &$resp) 
	{
		$info = &new InformationDisplay($reg, $req, $resp);
		
		//--------------------------------------------
		// Is this a good or a bad post?
		//--------------------------------------------
		
		if($req->get('rating') == 'good') 
		{
			$dir = 1;
		} 
		else if($req->get('rating') == 'bad') 
		{
			$dir = -1;
		} 
		else 
		{
			$info = &new InformationDisplay($reg, $req, $resp);
			$info->text('Please specify a valid rating.');
		}
		
		$post = $req->get('post_type') == 'thread' ? 'thread' : 'comment';
		$posts = $post .'s';
		$post_id = $post .'_id';
		
		// get the post
		$finder = &$this->getFinder($posts);
		$p = &$finder->find($req->get('post_id'));
		
		//--------------------------------------------
		// Figure out the comment and thread id's.
		//--------------------------------------------
		
		if($post == 'thread')
		{
			$comment_id = 0;
			$thread_id = $p->getId();
		}
		else
		{
			$comment_id = $p->getId();
			$thread_id = $p->get('thread_id');
		}
		
		// get the user
		$user = &$reg->get('user');
		
		//--------------------------------------------
		// Error checking
		//--------------------------------------------
		
		$author_id = $p->get('user_id');
		
		$is_author = ($user->getId() == $author_id);
		
		if($author_id <= K4_GUEST_ID)
		{
			$author_is_guest = TRUE;
		}
		
		if($post != 'comment')
		{
			//--------------------------------------------
			// If this is a thread, loop through the thread authors
			// to determine if one of them is this user.
			//--------------------------------------------
			
			$authors = &$p->getAuthors();
			while($authors->next())
			{
				$author = $authors->current();
				
				if($author->get('user_id') == $user->getId())
				{
					$is_author = TRUE;
				}
			}
		}
		
		//--------------------------------------------
		// More error checking...
		//--------------------------------------------
		
		// make sure we're not a guest and that we have permission to vote
		if(!$user->canDo('rate', $posts) || $user->get('user_id') == K4_GUEST_ID || $is_author) 
		{	
			$info->display('permsRequired');
		}
		
		// let's make sure that we've not rated this post yet
		$finder = &$this->getFinder('post_karma');
		$karma = &$finder->findWhere('thread_id=? AND comment_id=? AND user_id=?', array($thread_id, $comment_id, $user->getId()));
		
		// this person has voted, those cheaters!
		if($karma !== NULL) 
		{
			$info->text('You have already rated this post.');
		}
		
		//--------------------------------------------
		// Figure out the average post risk
		//--------------------------------------------
		
		if($post == 'thread') 
		{
			$finder = &$this->getFinder('threads');
			$stats = &$finder->selectWhere('SUM(t.karma_risk) AS total_karma_risk_sum, SUM(t.karma_reward) AS total_karma_reward_sum, COUNT(t.thread_id) AS total_thread_count', '', array());
			$avg_post_risk = @floatval($stats->get('total_karma_risk_sum') / $stats->get('total_thread_count'));
		} 
		else 
		{
			$avg_post_risk = 0.5;
		}
		
		//--------------------------------------------
		// Figure out the average user karma
		//--------------------------------------------
		
		$finder = &$this->getFinder('users');
		$stats = &$finder->selectWhere('SUM(karma) AS total_sum_karma, COUNT(user_id) AS total_user_count', '', array());
		$avg_usr_karma = @floatval($stats->get('total_sum_karma') / ($stats->get('total_user_count') - 1)); // -1 for guest user
		
		
		//-------------------------------------------------
		// let's figure out what type of impact this user should have
		// on this thread
		//-------------------------------------------------
		
		if($avg_usr_karma >= 0) 
		{
			// this will always be the case unless the db is corrupted or something
			
			//-------------------------------------------------
			// I'm thinking that instead of dividing by the average user karma, I 
			// base it off the number of standard deviations away from the average
			// karma this user is.
			//-------------------------------------------------
			
			$user_impact = @($user->get('karma') / $avg_usr_karma);
		} 
		else 
		{
			// this should never happen, but in the event, their impact will be VERY small
			$user_impact = $avg_risk / 100;
		}
		
		
		// if the poster is risking above the average, make each persons
		// rating worth that much more >:P
		if($p->get('karma_risk') > $avg_post_risk) 
		{
			$user_impact = $user_impact * ($p->get('karma_risk') / $avg_post_risk);
		}
		
		// if this is a comment, make the impact half as good/bad
		if($post == 'comment') 
		{
			$user_impact = $user_impact / 2;
		}
		
		$user_impact = round($user_impact, 2);
		$user_impact = $user_impact * $dir;
		
		
		//--------------------------------------------
		// By this point, it's ensured that the user impact on the post will never be
		// as great as the thread's karma risk. This is a good thing. Also, it's probable
		// that even with insane and crazy numbers in the database, the user impact will
		// never get above five. However, I might be proven wrong when there are lot's of
		// users posting and also in the instance of an outlier.
		//--------------------------------------------
		
		
		//--------------------------------------------
		// now let's figure out what the impact on the poster should
		// be... Now, I decided that the impact on the poster should
		// be half of that of the user on the post. I don't know why
		// I chose 1/2, I just did.
		//--------------------------------------------
		
		$poster_impact = round($p->get('karma_risk') / 2, 2) * $dir;
		
		
		// Now get the voter's gain.. this is just a base rate based off
		// of the thread's risk. Nothing interesting to it.
		$user_gain = round($p->get('karma_risk') / 10, 2);
		
		
		// we will use this finder for the next two queries
		$finder = &$this->getFinder('users');
		
		
		// if the poster id isn't a guest, update the poster's karma
		// TODO:{[Should we modify the karma of all of the authors of this thread?[rate[KarmaController}
		if(!$author_is_guest) 
		{
			$poster = &$finder->find($author_id);
			
			// this will only happen if the poster has disappeared from the database...
			if($poster !== NULL) 
			{
				$poster->set('karma', round($poster_impact + $poster->get('karma'), 2));
				$poster->save();
			}
		}
		
		
		// update this user's karma assuming this person isn't a guest
		if($user->get('user_id') > 1) 
		{
			$u = &$finder->find($user->get('user_id'));
			$u->set('karma', round($user_gain + $u->get('karma'), 2));
			$u->save();
		}
		
		
		// update this post's karma
		$p->set('karma_reward', round($p->get('karma_reward') + $user_impact, 2));
		$p->save();
		
		
		//--------------------------------------------
		// if we're rating a comment, make the rating of this comment SLIGHTLY affect the
		// rating of the thread. Why? Well, if a comment is good/bad, it makes the thread
		// that much better/worse.
		// **
		// still not too sure about this because this would mean that you can up or down
		// the karma of your own thread indirectly. Though by not ver much, it can still
		// make a difference.
		// **
		//--------------------------------------------
		
		if($post == 'comment') 
		{
			$finder = &$this->getFinder('threads');
			$thread = &$finder->find($thread_id);
			$thread->set('karma_reward', $thread->get('karma_reward') + ($user_impact / 1.5));
			$thread->save();
		}
		
		
		//--------------------------------------------
		// Add the entry to the karma records
		//--------------------------------------------
		
		$finder = &$this->getFinder('post_karma');
		$karma = &$finder->createRecord();
		$karma->set('thread_id', $thread_id);
		$karma->set('comment_id', $comment_id);
		$karma->set('user_id', $user->get('user_id'));
		$karma->set('rate_val', $user_impact);
		$karma->set('rate_time', time());
		$karma->save();
		
		//--------------------------------------------
		// A nice path for the referer.
		//--------------------------------------------
		
		if($post == 'comment') 
		{
			$referer = '/thread/'. $p->get('thread_id') .'/';
		}
		else
		{
			$referer = '/thread/'. $p->getId() .'/'. k4_us($p->get('name')) .'/';
		}
		
		$info->text('Thank you for rating this post.', $referer, 3);
	}
}

?>