colorsheet

<?php

class Matrix
{
    private const COLORS = [
        '41',
        '42',
        '43',
        '44',
        '46',
    ];

    private $n;
    private $m;
    private $items;
    private $processedMap;
    private $blocks;

    public function __construct(int $n, int $m)
    {
        $this->n = $n;
        $this->m = $m;

        $this->reset();
    }

    public function reset(): void
    {
        $this->items = [];
        $this->processedMap = [];
        $this->blocks = [];

        for ($i = 0; $i < $this->n; $i++) {
            $this->items[$i] = [];
            $this->processedMap[$i] = [];

            for ($j = 0; $j < $this->m; $j++) {
                $this->items[$i][$j] = rand(0, count(self::COLORS) - 1);
                $this->processedMap[$i][$j] = 0;
            }
        }

        foreach (self::COLORS as $color => $_) {
            $this->blocks[$color] = 0;
        }
    }

    public function print(bool $printHeader = false): void
    {
        if ($printHeader) {
            print 'X';
            for ($i = 0; $i < count($this->items[0]); $i++) {
                print ' | ' . $i;
            }
            print PHP_EOL;
        }

        foreach ($this->items as $j => $row) {
            if ($printHeader) {
                print $j;
            }

            $colorizedRow = array_map([$this, 'getColorizedOutput'], $row);
            print implode('', $colorizedRow) . PHP_EOL;
        }
    }

    public function compute(): void
    {
        foreach ($this->items as $i => $row) {
            foreach ($row as $j => $color) {
                if ($this->processedMap[$i][$j]) {
                    continue;
                }

                $blockSize = $this->passBlock($i, $j);
                $this->blocks[$color] = max($this->blocks[$color], $blockSize);
            }
        }

        foreach ($this->blocks as $color => $size) {
            print $this->getColorizedOutput($color) . ': ' . $size . PHP_EOL;
        }
    }

    private function passBlock(int $i, int $j): int
    {
        if (!isset($this->items[$i][$j]) || $this->processedMap[$i][$j]) {
            return 0;
        }

        $this->visit($i, $j);

        $possibleNeighbors = [
            [$i + 1, $j],
            [$i - 1, $j],
            [$i, $j + 1],
            [$i, $j - 1],
        ];

        $currentStepResult = 1;
        foreach ($possibleNeighbors as $index) {
            list($nearI, $nearJ) = $index;
            if ($this->items[$i][$j] === $this->items[$nearI][$nearJ]) {
                $currentStepResult += $this->passBlock($nearI, $nearJ);
            }
        }

        return $currentStepResult;
    }

    private function visit(int $i, int $j): void
    {
        $this->processedMap[$i][$j] = 1;
    }

    private function getColorizedOutput(int $color): string
    {
        return "\e[1;37;" . self::COLORS[$color] . "m " . $color . " \e[0m";
    }
}

$matrix = new Matrix(40, 50);
$matrix->print();
$matrix->compute();