<?php

function getOpcode($value)
{
    [$mode3, $mode2, $mode1, $op1, $op2] = str_split(
        str_pad($value, 5, '0', STR_PAD_LEFT)
    );
    return [$op1 . $op2, $mode1, $mode2, $mode3];
}

function getValue($mem, $src, $mode, $base)
{
    if ($mode === '1') {
        return $src;
    }

    if ($mode === '2') {
        return $mem[$base + $src] ?? '0';
    }
    return $mem[$src] ?? '0';
}

function getLocation($src, $mode, $base)
{
    if ($mode === '2') {
        return $base + $src;
    }

    return $src;
}

function work(&$mem, &$i, &$base, $input)
{
    while ($i < count($mem)) {
        [$opcode, $mode1, $mode2, $mode3] = getOpcode($mem[$i]);
        if ($opcode === '01') {
            [$src1, $src2, $dest] = array_slice($mem, $i + 1, 3);
            $mem[getLocation($dest, $mode3, $base)] =
                getValue($mem, $src1, $mode1, $base) +
                getValue($mem, $src2, $mode2, $base);
            $i += 4;
        } elseif ($opcode === '02') {
            [$src1, $src2, $dest] = array_slice($mem, $i + 1, 3);
            $mem[getLocation($dest, $mode3, $base)] =
                getValue($mem, $src1, $mode1, $base) *
                getValue($mem, $src2, $mode2, $base);
            $i += 4;
        } elseif ($opcode === '03') {
            $dest = $mem[$i + 1];
            $mem[getLocation($dest, $mode1, $base)] = $input;
            $i += 2;
        } elseif ($opcode === '04') {
            $src1 = $mem[$i + 1];
            $i += 2;
            return getValue($mem, $src1, $mode1, $base);
        } elseif ($opcode === '05') {
            [$src1, $src2] = array_slice($mem, $i + 1, 2);
            $val1 = getValue($mem, $src1, $mode1, $base);
            if ($val1 != '0') {
                $i = getValue($mem, $src2, $mode2, $base);
            } else {
                $i += 3;
            }
        } elseif ($opcode === '06') {
            [$src1, $src2] = array_slice($mem, $i + 1, 2);
            $val1 = getValue($mem, $src1, $mode1, $base);
            if ($val1 == '0') {
                $i = getValue($mem, $src2, $mode2, $base);
            } else {
                $i += 3;
            }
        } elseif ($opcode === '07') {
            [$src1, $src2, $dest] = array_slice($mem, $i + 1, 3);
            $dest = getLocation($dest, $mode3, $base);
            if (
                getValue($mem, $src1, $mode1, $base) <
                getValue($mem, $src2, $mode2, $base)
            ) {
                $mem[$dest] = '1';
            } else {
                $mem[$dest] = '0';
            }
            $i += 4;
        } elseif ($opcode === '08') {
            [$src1, $src2, $dest] = array_slice($mem, $i + 1, 3);
            $dest = getLocation($dest, $mode3, $base);
            if (
                getValue($mem, $src1, $mode1, $base) ==
                getValue($mem, $src2, $mode2, $base)
            ) {
                $mem[$dest] = '1';
            } else {
                $mem[$dest] = '0';
            }
            $i += 4;
        } elseif ($opcode === '09') {
            $src1 = $mem[$i + 1];
            $val = getValue($mem, $src1, $mode1, $base);
            $base += $val;
            $i += 2;
        } elseif ($opcode === '99') {
            return -1;
        } else {
            echo "UNKNOWN OPCODE" . PHP_EOL;
            break;
        }
    }
}
$input = trim(file_get_contents('input'));

$mem = explode(',', $input);

$i = 0;
$base = 0;
$x = 0;

$result = 0;
$direction = 'up';
$color = 0;
$position = [0, 0];
$panels = [];
$panels[0][0] = 1;
$count = 0;
while (1) {
    $result = work($mem, $i, $base, getColor($panels, $position));
    if ($result === -1) {
        break;
    }
    if (!$x) {
        $color = $result;
    } else {
        $direction = switchDirection($direction, $result);
    }
    $x += 1;
    if ($x === 2) {
        $x = 0;
        $count += paint($panels, $position, $color);
        $position = move($position, $direction);
    }
}

printMap($panels);

function getColor($panels, $position)
{
    [$x, $y] = $position;
    return $panels[$y][$x] ?? 0;
}

function paint(&$panels, $position, $color)
{
    [$x, $y] = $position;
    $result = isset($panels[$y][$x]) ? 0 : 1;
    $panels[$y][$x] = $color;
    return $result;
}

function move($position, $direction)
{
    [$x, $y] = $position;
    switch ($direction) {
        case 'up':
            return [$x, $y - 1];
        case 'right':
            return [$x + 1, $y];
        case 'down':
            return [$x, $y + 1];
        case 'left':
            return [$x - 1, $y];
    }
}

function switchDirection($direction, $result)
{
    switch ($direction) {
        case 'up':
            return !$result ? 'left' : 'right';
        case 'right':
            return !$result ? 'up' : 'down';
        case 'down':
            return !$result ? 'right' : 'left';
        case 'left':
            return !$result ? 'down' : 'up';
    }
}

function printMap($map)
{
    $minY = min(array_keys($map));
    $maxY = max(array_keys($map));
    $minX = PHP_INT_MAX;
    $maxX = PHP_INT_MIN;
    foreach ($map as $y => $xValues) {
        $myMin = min(array_keys($xValues));
        $myMax = max(array_keys($xValues));
        if ($myMin < $minX) {
            $minX = $myMin;
        }
        if ($myMax > $maxX) {
            $maxX = $myMax;
        }
    }

    for ($y = $minY; $y <= $maxY; $y += 1) {
        for ($x = $minX; $x <= $maxX; $x += 1) {
            $color = $map[$y][$x] ?? 0;
            if (!$color) {
                echo ' ';
            } else {
                echo '#';
            }
        }
        echo "\n";
    }
}