<?php 
setlocale(LC_ALL, "de_DE@euro", "de_DE", "de", "ge");
set_include_path(get_include_path() . PATH_SEPARATOR . "./lib/");

// Configs
require_once("config/participo.php");
require_once $config['basePath'] . "/config/cwsvJudo.config.php";

// Libs
require_once("participoLib/user.php");

participo::init($cwsvJudoConfig);

$pmelo = new PmElo();

class PmElo{
    function __construct()
    {
        // $this->var_log($_SESSION, "session");
        // starting/continuing a session
        session_start();

        // create 'pmelo' section in the sessions data
        if(!array_key_exists('pmelo', $_SESSION)){
            $_SESSION['pmelo'] = [];
        }        
        // - data storage for id-s of chosen fighters
        if(!array_key_exists('fighterIds', $_SESSION['pmelo'])){
            $_SESSION['pmelo']['fighterIds'] = []; 
        }

        // check for action in post data
        if(array_key_exists('pmelo', $_POST)){
            if(array_key_exists('fighterIds', $_POST['pmelo'])){
                $_SESSION['pmelo']['fighterIds']=$_POST['pmelo']['fighterIds'];
            }
            // $this->var_log($_SESSION, "session");
        }

        // load/recreate ranking data
        if(!is_file(self::$pmeloJson)){
            $this->log['info'][] = "Couldn't find `".self::$pmeloJson."`. Create a new one!";
            file_put_contents(self::$pmeloJson, json_encode([]));
        }

        // init members
        $this->trainees = self::getTrainees();
        $this->var_log(array_map(function($user){return $user->getFirstName();},$this->trainees), "trainees from db");
        $this->rankings = $this->createRankings();
        $this->var_log(array_map(function($id){return $this->trainees[$id]->getFirstName();},$this->rankings), "current ranking");
        $this->fighters = [];
        foreach($_SESSION['pmelo']['fighterIds'] as $id){
            $this->fighters[$id] = $this->trainees[$id];
        };
        $this->var_log(array_map(function($user){return $user->getFirstName();},$this->fighters), "fighters");
        

        // save the updated ranking
        // @todo should be in destructor
        self::saveRankings($this->rankings);
    }

    function __destruct(){
        // sad, the destructor is not allowed to use file_put_contents
    }
    
    // load all active trainees into a id=>User assoc array
    public static function getTrainees(){
        $traineeList = array_map('User::fromDbArray', User::dbSelectWithAttribute(4));
        $traineeAssocArray = [];
        foreach($traineeList as $trainee){
            $traineeAssocArray[$trainee->getId()] = $trainee;
        }
        return $traineeAssocArray;
    }

    // load ranking from json file
    public static function loadRankings(){
        return json_decode(file_get_contents(self::$pmeloJson));
    }
    
    // save a ranking to json file
    public static function saveRankings(array $rankings){
        file_put_contents(self::$pmeloJson, json_encode($rankings));
    }

    // simple logger to a logging buffer
    function var_log($variable, string $prefix=null, string $logChannel='info'){
        if(!in_array($logChannel, ['info', 'warning', 'error'])){
            $logChannel='info';
        }
        $prefix = (!empty($prefix) ? $prefix.": " : "");
        $this->log[$logChannel][]=$prefix.var_export($variable, true);
    }

    // create the ranking for the current session (load saved ranking from file, remove old trainees, add new trainees)
    public function createRankings(){
        // load the last state of the ranking
        $loadedRanking = self::loadRankings();
        $this->var_log(array_map(function($id){$user=$this->trainees[$id]; return $user->getFirstName();}, $loadedRanking), "loaded ranking");

        // check if the ranked trainees still are in training
        // - the ranking with
        $cleanRanking = [];
        // - trainees that aren't currently in the ranking for later inserting
        $toBeInsertedTrainees = $this->trainees;
        foreach($loadedRanking as $id){
            if(array_key_exists($id, $this->trainees)){
                // userId is still in training, so append it to the cleaned up ranking
                $cleanRanking[] = $id;
                // trainees already in the ranking we won't have to insert manual
                unset($toBeInsertedTrainees[$id]);
            }
        }
        
        // get the ids of the to be inserted trainees sorted by the birthday
        $newTraineesIds = array_map(function($u){return $u->getId();},$toBeInsertedTrainees);
        usort(
            $newTraineesIds
            , function($lhs, $rhs){
                return $this->trainees[$lhs]->getStrBirthday() < $this->trainees[$rhs]->getStrBirthday() ? -1 : ($this->trainees[$lhs]->getStrBirthday() > $this->trainees[$rhs]->getStrBirthday() ? 1 : 0);
            }
        );
        // $this->var_log(
        //     array_map(
        //         function($id){return $this->trainees[$id]->getStrBirthday()." ".$this->trainees[$id]->getFirstName();}
        //         , $newTraineesIds
        //     )
        //     , "newTraineesBy B-Day"
        // );

        // now we do a mergesort (step) 
        $updatedRanking = [];
        $idxNewTrainees = count($newTraineesIds)-1;
        $idxRanking = count($cleanRanking)-1;
        // - while we can merge, we merge
        while( ($idxRanking >= 0) && ($idxNewTrainees >= 0) ){
            // $this->var_log( [$idxRanking.", ".$idxNewTrainees=>$updatedRanking] );
            // $this->var_log(
            //     [$this->trainees[$cleanRanking[$idxRanking]]->getStrBirthday(), $this->trainees[$newTraineesIds[$idxRanking]]->getStrBirthday()]
            // );
            if( 
                $this->trainees[$cleanRanking[$idxRanking]]->getDateOfBirth()
                > $this->trainees[$newTraineesIds[$idxNewTrainees]]->getDateOfBirth()
            ){
                // $this->var_log( $this->trainees[$cleanRanking[$idxRanking]]->getFirstName(), "merge ranking insert" );
                array_unshift($updatedRanking, $cleanRanking[$idxRanking]);
                $idxRanking-=1;
            }else{
                // $this->var_log( $this->trainees[$newTraineesIds[$idxNewTrainees]]->getFirstName(), "merge trainees insert" );
                array_unshift($updatedRanking, $newTraineesIds[$idxNewTrainees]);
                $idxNewTrainees-=1;
            }
        }
        // $this->var_log(
        //     ["idxR ".$idxRanking." idxNT ".$idxNewTrainees=>[$cleanRanking, $newTraineesIds]]
        //     , "after merge"
        // );
        while( $idxRanking >= 0 ){
            // $this->var_log( $this->trainees[$cleanRanking[$idxRanking]]->getFirstName(), "rest ranking insert" );
            array_unshift($updatedRanking, $cleanRanking[$idxRanking]);
            $idxRanking-=1;
        }
        while( $idxNewTrainees >= 0 ){
            // $this->var_log( $this->trainees[$newTraineesIds[$idxNewTrainees]]->getFirstName(), "rest newTrainees insert" );
            array_unshift($updatedRanking, $newTraineesIds[$idxNewTrainees]);
            $idxNewTrainees-=1;
        }
        return $updatedRanking;
    }

    public $log = ['error'=>[], 'warning'=>[], 'info'=>[]];
    public $fighters = null;
    public $trainees = null;
    // list of id-s in the order of the current ranking
    public $rankings = null;

    static $pmeloJson="./pmeloRanking.json";
}