LFS PRISM plugin ABGap 0.0.6

<?php
class ABGap extends Plugins
{
    const URL = 'https://www.lfs.net/forum/thread/89031-ABGap-%28code-dump%2C-unsupported%29';
    const NAME = 'ABGap';
    const AUTHOR = 'notanillusion';
    const VERSION = '0.0.6';
    const DESCRIPTION = 'Gap delta to car ahead and behind';

    public function __construct() {
        $this->registerPacket('onLap', ISP_LAP);    // record times, display gaps
        $this->registerPacket('onMci', ISP_MCI);    // update positions
        $this->registerPacket('onNpl', ISP_NPL);    // add new plids
        $this->registerPacket('onPll', ISP_PLL);    // remove unusued plids
        $this->registerPacket('onRst', ISP_RST);    // update total splits and laps, fresh db table
        $this->registerPacket('onSpx', ISP_SPX);    // record times, display gaps
        $this->registerPacket('onSta', ISP_STA);    // update viewplid

        $this->consts = array(
            'GAP_AHEAD' => -1,
            'GAP_BEHIND' => 1,

            'SPLIT_LAP' => 255
        );

        $this->db = $this->newDb();
        if (!$this->db)
            die('Failed to create database.'.PHP_EOL);

        $result = $this->createTable($this->db);
        if (!$result)
            die('Failed to create table.'.PHP_EOL);

        $this->playerData = array();    // plid => array(pos, lap), ...
        $this->viewPlid = 0;
        $this->laps = 0;
        $this->splits = 0;
    }

    public function __destruct() {
        $this->db->close();
    }

    /// *** PACKET FUNCTIONS START *** ///

    public function onLap(IS_LAP $lap) {
        if (!count($this->playerData))      // ignore hotlap mode
            return;

        $pos = $this->playerData[$lap->PLID]['pos'];

        $q = "INSERT INTO timing (plid, lap, split, pos, time)
            VALUES ($lap->PLID, $lap->LapsDone, ".$this->consts['SPLIT_LAP'].", $pos, $lap->ETime)";

        $result = $this->db->exec($q);

        // Don't check for gap ahead if we're 1st.
        if ($lap->PLID === $this->viewPlid && $this->playerData[$this->viewPlid]['pos'] > 1) {
            $plidAhead = $this->getPlidAhead($pos, $lap->LapsDone, $this->consts['SPLIT_LAP']);

            // Sometimes when cars are really close to one another across a split, the SPX for the car behind in positions
            // can arrive first. Don't display gap when that happens.
            if ($plidAhead === null) {
                return;
            }
            $this->sendGap($plidAhead, $this->consts['GAP_AHEAD'], $lap->LapsDone, $this->consts['SPLIT_LAP']);
        }

        // Don't check for gap behind if we're last.
        if (!$this->isLastPlaceByPlid($this->viewPlid)) {
            if ($this->getPlidAhead($pos, $lap->LapsDone, $this->consts['SPLIT_LAP']) == $this->viewPlid)
                $this->sendGap($lap->PLID, $this->consts['GAP_BEHIND'], $lap->LapsDone, $this->consts['SPLIT_LAP']);
        }
    }

    public function onMci(IS_MCI $mci) {
        foreach ($mci->Info as $compcar) {
            if (!$compcar->Position)
                continue;
            $this->playerData[$compcar->PLID]['pos'] = $compcar->Position;
            $this->playerData[$compcar->PLID]['lap'] = $compcar->Lap;
        }
    }

    public function onNpl(IS_NPL $npl) {
        $this->playerData[$npl->PLID]['pos'] = $npl->NumP;
        $this->playerData[$npl->PLID]['lap'] = 1;
    }

    public function onPll(IS_PLL $pll) {
        unset($this->playerData[$pll->PLID]);
    }

    public function onRst(IS_RST $rst) {
        $this->laps = $rst->RaceLaps;
        $this->splits = $this->getNumSplitsRst($rst);

        $this->playerData = array();

        $result = $this->createTable($this->db);
        if (!$result) {
            echo('Failed to create table.'.PHP_EOL);
            return;
        }
}

    public function onSpx(IS_SPX $spx) {
        if (!count($this->playerData))
            return;

        $pos = $this->playerData[$spx->PLID]['pos'];
        $lap = $this->playerData[$spx->PLID]['lap'];

        if (!$lap) $lap++;

        $q = "INSERT INTO timing (plid, lap, split, pos, time)
            VALUES ($spx->PLID, $lap, $spx->Split, {$this->playerData[$spx->PLID]['pos']}, $spx->ETime)";

        $result = $this->db->exec($q);

        if ($spx->PLID === $this->viewPlid && $this->playerData[$this->viewPlid]['pos'] > 1) {
            $plidAhead = $this->getPlidAhead($pos, $lap, $spx->Split);

            if ($plidAhead === null) {
                return;
            }
            $this->sendGap($plidAhead, $this->consts['GAP_AHEAD'], $lap, $spx->Split);
        }

        if (!$this->isLastPlaceByPlid($this->viewPlid)) {
            if ($this->getPlidAhead($pos, $lap, $spx->Split) == $this->viewPlid) {
                $this->sendGap($spx->PLID, $this->consts['GAP_BEHIND'], $lap, $spx->Split);
            }
        }
    }

    public function onSta(IS_STA $sta) {
        $this->viewPlid = $sta->ViewPLID;
    }

    /// *** PACKET FUNCTIONS END *** ///

    function createTable($db) {
        $q = 'DROP TABLE timing';
        @$this->db->exec($q);

        $q = 'CREATE TABLE timing(
            id INTEGER PRIMARY KEY ASC,
            plid INTEGER,
            lap INTEGER,
            split INTEGER,
            pos INTEGER,
            time INTEGER
        )';

        $result = $this->db->exec($q);

        return $result;
    }

    function getNumSplitsRst($rst) {
        $splits = 0;

        for ($i = 3; $i > 0; $i--) {
            if ($rst->{"Split$i"} && $rst->{"Split$i"} != 65535) {
                $splits = $i;
                break;
            }
        }
        return $splits;
    }

    function getPlidAhead($pos, $lap, $split) {
        $pos--;

        $q = "SELECT plid FROM timing WHERE pos=$pos AND lap=$lap AND split=$split;";
        $result = $this->db->query($q);

        if ($result === false)
            return;
        $row = $result->fetchArray();

        return $row['plid'];
    }

    function getTime($plid, $lap, $split) {
        $q = "SELECT * FROM timing WHERE plid=$plid AND lap=$lap AND split=$split;";
        $result = $this->db->query($q);

        $time = 0;

        while($row = $result->fetchArray()) {
            if (array_key_exists('time', $row))
                $time = $row['time'];
        }

        return $time;
    }

    function isLastPlaceByPlid($plid) {
        if ($this->playerData[$plid]['pos'] >= count($this->playerData)) {
            return true;
        }

        return false;
    }

    function ms2str ($ms, $ahead) {
        $retval = '';

        $hour = abs($ms / (1000 * 60 * 60));
        if ($hour >= 1) {
            $retval .= strval(intval($hour)) . ':';
        }

        $min = ($hour - intval($hour)) * 60;
        if ($hour >= 1 && $min < 1) {
            $retval .= '00:';
        }
        else if ($min >= 10) {
            $retval .= strval(intval($min)) . ':';
        }
        else if ($min > 1 && $min < 10) {
            $retval .= '0' . strval(intval($min)) . ':';
        }

        $sec = ($min - intval($min)) * 60;
        $retval .= number_format($sec, 3);

        if ($ms >= 0 && $ahead < 0) {
            $retval = "^1+$retval";
        }

        if ($ms < 0 && $ahead < 0) {
            $retval = "^2-$retval";
        }

        if ($ms >= 0 && $ahead > 0) {
            $retval = "^1-$retval";
        }

        if ($ms < 0 && $ahead > 0) {
            $retval = "^2+$retval";
        }

        return $retval;
    }

    function newDb() {
        $db = new SQLite3(':memory:');
        return $db;
    }

    function getGap($a, $b, $lap, $split) {
        $plidACurTime = $this->getTime($a, $lap, $split);
        $plidBCurTime = $this->getTime($b, $lap, $split);
        $gap = $plidACurTime - $plidBCurTime;

        return $gap;
    }

    function sendGap($plid, $mode, $lap, $split) {
        if ($split === false)
            return;

        if ($this->splits === 0) {
            $split = 255;
        }

        $curGap = $this->getGap($this->viewPlid, $plid, $lap, $split);

        switch ($split) {
            case 255:
                $split = $this->splits;
            break;

            case 1:
                $split = 255;
                $lap--;
            break;

            default:
                if ($this->splits === 0) {
                    $lap--;
                } else {
                    $split--;
                }
            break;
        }

        $prevGap = $this->getGap($this->viewPlid, $plid, $lap, $split);

        $gapDelta = $curGap - $prevGap;

        if ($mode == $this->consts['GAP_BEHIND']) {
            $msg = '^3Gap delta to car behind: ';
        } else {
            $msg = '^3Gap delta to car ahead: ';
        }

        $timemsg = $this->ms2str($gapDelta, $mode);
        $msg .= $timemsg;

        IS_MSL()->Msg($msg)->Send();
    }
}
?>