<?php

class Schedule {
    /** @var string[] $abbreviations */
    private $abbreviations;
    
    /** @var DateTime[] $displaydates */
    private $displaydates;

    /** @var string[] $stations */
    private $stations;

    /** @var string[] $stations */
    private $optstations;

    /** @var array[] $stations */
    private $wantedstations;

    /** @var array $improps */
    private $improps;

    /** @var GDIMAGE $this->image */
    private $image;

    /** @var boolean $darkmode */
    private $darkmode;

    /** @var boolean $debug */
    private $debug;

    public function __construct(array $displaydates, array $stations, array $optstations = [], $wantedstations = [], $darkmode = false) {
        $this->abbreviations = [];
        $this->training = $this->event = false;
        $this->displaydates = $displaydates;
        $this->stations = $stations;
        $this->optstations = $optstations;
        $this->wantedstations = $wantedstations;
        $this->improps = [];
        $this->darkmode = $darkmode;
        //$this->debug = true;
    }
    
    public function createImage() {
        $rawData = $this->fetchData();

        $relevantBookings = [];
        foreach($this->stations as $station) {
            $relevantBookings[$station] = [];
        }

        foreach($rawData as $item) {
            if(in_array($item['station']['ident'], $this->stations)) {
                $relevantBookings[$item['station']['ident']][] = [
                    'starts_at' => new DateTime($item['starts_at']),
                    'ends_at' => new DateTime($item['ends_at']),
                    'lastname' => $item['controller']['lastname'],
                    'firstname' => $item['controller']['firstname'],
                    'training' => $item['training'],
                    'event' => $item['event']
                ];
            }
        }

        putenv('GDFONTPATH=' . realpath('.'));
        $this->improps['font'] = "UbuntuMono-Regular";
        // $this->improps['font'] = "EuroScope";
        $this->improps['width'] = 100 * count($this->displaydates) + 100;
        $this->improps['height'] = 25 * count($this->stations) + 600;

        if(!$this->darkmode) {
            $this->image = imagecreatetruecolor($this->improps['width'], $this->improps['height']);
            $this->improps['bg'] = imagecolorallocate($this->image, 255, 255, 255);
            $this->improps['black'] = imagecolorexact($this->image, 0, 0, 0);
            $this->improps['open'] = imagecolorexact($this->image, 155, 155, 155);
            $this->improps['wanted'] = imagecolorexact($this->image, 255, 0, 0);
            $this->improps['event'] = imagecolorexact($this->image, 0, 255, 0);
            $this->improps['training'] = imagecolorexact($this->image, 50, 100, 255);
            $this->improps['eventtraining'] = imagecolorexact($this->image, 0, 255, 255);
        } else {
            $this->image = imagecreatetruecolor($this->improps['width'], $this->improps['height']);
            $this->improps['bg'] = imagecolorallocate($this->image, 0, 0, 0);
            $this->improps['black'] = imagecolorexact($this->image, 255, 255, 255);
            $this->improps['open'] = imagecolorexact($this->image, 155, 155, 155);
            $this->improps['wanted'] = imagecolorexact($this->image, 255, 0, 0);
            $this->improps['event'] = imagecolorexact($this->image, 0, 255, 0);
            $this->improps['training'] = imagecolorexact($this->image, 50, 100, 255);
            $this->improps['eventtraining'] = imagecolorexact($this->image, 0, 255, 255);
        }
        imagefill($this->image, 0, 0, $this->improps['bg']);

        $this->improps['lineheight'] = 20;
        $sepheight = 25;

        for($i = 0; $i < count($this->displaydates); $i++) {
            imagefttext($this->image, 11, 0, ($i) * 100 + 100, 25, $this->improps['black'], $this->improps['font'], $this->displaydates[$i]->format("D d.m."));
        }

        $height = 40;
        foreach($this->stations as $station) {
            if($this->debug)  echo "\n". $station . "\th$height";
            imageline($this->image, 0, $height + 5, $this->improps['width'], $height + 5, $this->improps['open']);
            if($station == '--') {
                $height += $sepheight;
                continue;
            }
            $height += $this->improps['lineheight'];
            
            $lines = 0;
            for($i = 0; $i < count($this->displaydates); $i++) {
                $l = $this->addBookingData($station, $this->displaydates[$i], $relevantBookings[$station], $i * 100 + 100, $height);
                $lines = $l > $lines ? $l : $lines;
                if($this->debug) echo "\t" . $this->displaydates[$i]->format("m-d") . ": " . $lines;
            }
            if(!in_array($station, $this->optstations) && $lines < 1)  $lines = 1;
            if($this->debug) echo "\tl$lines";
            if($lines > 0) {
                imagefttext($this->image, 11, 0, 10, $height, $this->improps['black'], $this->improps['font'], $station);
                imageline($this->image, 0, $height + 5, $this->improps['width'], $height + 5, $this->improps['open']);
            }
            $height += ($lines - 1) * $this->improps['lineheight'];
            
        }

        for($i = 0; $i < count($this->displaydates); $i++) {
            imageline($this->image, 100 * $i + 92, 0, 100 * $i + 92, $height + 5, $this->improps['open']);
        }

        $height += $this->improps['lineheight'] + 5;
        //imagefttext($this->image, 11, 0, 10, $height, $this->improps['wanted'], $this->improps['font'], 'Wanted');
        imagefttext($this->image, 11, 0, 100, $height, $this->improps['training'], $this->improps['font'], 'Training');
        imagefttext($this->image, 11, 0, 200, $height, $this->improps['event'], $this->improps['font'], 'Event');
        imagefttext($this->image, 11, 0, 300, $height, $this->improps['eventtraining'], $this->improps['font'], 'Event + Training');

        $height += $this->improps['lineheight'] * 2;
        $namelength = 0;
        asort($this->abbreviations);
        foreach($this->abbreviations as $name) {
            $namelength = strlen($name) > $namelength ? strlen($name) : $namelength;
        }
        $collength = ($namelength + 10) * 8;
        $cols = floor( ($this->improps['width'] - 10) / $collength);
        $col = 0;
        $row = 0;
        foreach($this->abbreviations as $abbrv => $name) {
            imagefttext($this->image, 11, 0, $col * $collength + 10, $height + $row * $this->improps['lineheight'], $this->improps['black'], $this->improps['font'], $abbrv . ": " . $name);
            $row = ($col + 1) >= $cols ? $row + 1 : $row;
            $col = ($col + 1) >= $cols ? 0 : $col + 1;
        }

        $height += $this->improps['lineheight'] * ($row +2);
        imagefttext($this->image, 11, 0, 10, $height, $this->improps['open'], $this->improps['font'], "Generated " . (new DateTime("now", new DateTimeZone('UTC')))->format('d.m.Y H:i:s') . "z" );
        $this->image = imagecrop($this->image, ['x' => 0, 'y' => 0, 'width' => $this->improps['width'], 'height' => $height+5]);

        return $this->image;
    }
    
    private function addBookingData($station, $date, $bookings, $x, $height) {
        $count = 0;
        foreach($bookings as $booking) {
            if($booking['starts_at']->format('Y-m-d') == $date->format('Y-m-d')) {
                $abbrv = substr($booking['firstname'], 0, 3) . substr($booking['lastname'], 0, 3); //TODO
                $this->abbreviations[$abbrv] = $booking['firstname'] . " " . $booking['lastname'];
                if($booking['training'] && $booking['event']) $color = $this->improps['eventtraining'];
                elseif($booking['training']) $color = $this->improps['training'];
                elseif($booking['event']) $color = $this->improps['event'];
                else $color = $this->improps['black'];
                imagefttext($this->image, 11, 0, $x, $height + $count * $this->improps['lineheight'], $color, 
                    $this->improps['font'], $abbrv . " " . $booking['starts_at']->format('H') . "-" . $booking['ends_at']->format('H'));
                $count++;
            }
        }
        if($count == 0 && !in_array($station, $this->optstations)) {
            if(!$this->dayIsWanted($station, $date))
                imagefttext($this->image, 10, 0, $x, $height, $this->improps['open'], $this->improps['font'], "Open");
            else
                imagefttext($this->image, 10, 0, $x, $height, $this->improps['wanted'], $this->improps['font'], "WANTED!");
        }
        return $count;
    }

    private function fetchData() {
        $url = sprintf("https://vatsim-germany.org/api/booking/atc/daterange/%s/%s", $this->displaydates[0]->modify("-1 day")->format("d.m.Y"), $this->displaydates[count($this->displaydates) -1]->format("d.m.Y"));
        $this->displaydates[0]->modify("+1 day");
        if($this->debug) echo "\nUrl: $url";
        $curl = curl_init();
        curl_setopt($curl, CURLOPT_URL, $url ) ;
        curl_setopt($curl, CURLOPT_HTTPHEADER, ["X-Requested-With: XMLHttpRequest"]);
        curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
        
        // curl_setopt($curl, CURLOPT_VERBOSE, true);
        // $verbose = fopen('php://temp', 'w+');
        // curl_setopt($curl, CURLOPT_STDERR, $verbose);
        
        $result = curl_exec($curl);
        
        // if ($result === FALSE) {
        //     printf("cUrl error (#%d): %s<br>\n", curl_errno($curl),
        //            htmlspecialchars(curl_error($curl)));
        // }
        // rewind($verbose);
        // $verboseLog = stream_get_contents($verbose);
        // echo "Verbose information:\n<pre>", htmlspecialchars($verboseLog), "</pre>\n";
        
        curl_close($curl);
        return json_decode($result, true);
    }


    public static function EveryXDaysFromStartdate($startdate, $x = 1, $numberofdates = 1) {
        $startdate = new DateTime($startdate, new DateTimeZone('UTC'));
        $days = [];
        while(count($days) < $numberofdates) {
            if(new DateTime('today', new DateTimeZone('UTC')) <= $startdate) {
                $days[] = clone($startdate);
            }
            $startdate->add(new DateInterval(sprintf("P%dD", $x)));
        }
        return $days;
    }

    public static function EveryXWeeksFromStartdate($startdate, $x = 1, $numberofdates = 1) {
        return self::EveryXDaysFromStartdate($startdate, $x * 7, $numberofdates);
    }

    public static function EveryWeekday($dayoftheweek, $numberofdates = 1) {
        $startdate = new DateTime($dayoftheweek, new DateTimeZone('UTC'));
        $days = [];
        while(count($days) < $numberofdates) {
            $days[] = clone($startdate);
            $startdate->add(new DateInterval("P7D"));
        }
        return $days;
    }

    public static function WholeWeek($startdate = "today") {
        $days = [];
        $startdate = new DateTime($startdate, new DateTimeZone('UTC'));
        for($i = 0; $i < 7; $i++) {
            $days[] = clone($startdate);
            $startdate->add(new DateInterval("P1D"));
        }
        return $days;
    }

    public static function processWantedDays(...$args) {
        if(count($args) % 2 == 1) throw new Exception("Even number of arguments required.");
        $r = [];
        for($i = 0; $i < count($args); $i += 2) {
            foreach($args[$i] as $station) {
                if(!isset($r[$station])) $r[$station] = [];
                foreach($args[$i + 1] as $date) {
                    $r[$station][] = $date;
                }
            }
        }
        return $r;
    }

    private function dayIsWanted($station, $date) {
        if(!isset($this->wantedstations[$station])) return false;
        foreach($this->wantedstations[$station] as $target) {
            if($target->format("Y-m-d") == $date->format("Y-m-d")) return true;
        }
        return false;
    }
}