<?php

declare(strict_types=1);

const STATIC_CACHE_ITERATIONS = 1_000_000;
const STATIC_CACHE_WARMUPS = 2;
const STATIC_CACHE_ROUNDS = 5;

class StaticCacheData
{
    public static array $cache = [];

    public static function getData(): array
    {
        $class = static::class;
        if (!isset(self::$cache[$class])) {
            self::$cache[$class] = ['table' => 'users'];
        }
        return self::$cache[$class];
    }

    public static function getTable(): string
    {
        return static::getData()['table'];
    }
}

final class StaticSlotData
{
    public static int $counter = 1;

    public static function measureSelfRead(): array
    {
        $best = PHP_FLOAT_MAX;
        $checksum = 0;
        for ($round = 0; $round < STATIC_CACHE_WARMUPS + STATIC_CACHE_ROUNDS; $round++) {
            $sum = 0;
            $start = hrtime(true);
            for ($i = 0; $i < STATIC_CACHE_ITERATIONS; $i++) {
                $sum += self::$counter;
            }
            $elapsed = hrtime(true) - $start;
            if ($round >= STATIC_CACHE_WARMUPS && $elapsed < $best) {
                $best = $elapsed;
            }
            $checksum += $sum;
        }
        return [$best / STATIC_CACHE_ITERATIONS, $checksum];
    }

    public static function measureSelfWrite(): array
    {
        $best = PHP_FLOAT_MAX;
        $checksum = 0;
        for ($round = 0; $round < STATIC_CACHE_WARMUPS + STATIC_CACHE_ROUNDS; $round++) {
            $start = hrtime(true);
            for ($i = 0; $i < STATIC_CACHE_ITERATIONS; $i++) {
                self::$counter = $i;
            }
            $elapsed = hrtime(true) - $start;
            if ($round >= STATIC_CACHE_WARMUPS && $elapsed < $best) {
                $best = $elapsed;
            }
            $checksum += self::$counter;
        }
        return [$best / STATIC_CACHE_ITERATIONS, $checksum];
    }
}

function measureExplicitStaticRead(): array
{
    StaticSlotData::$counter = 1;
    $best = PHP_FLOAT_MAX;
    $checksum = 0;
    for ($round = 0; $round < STATIC_CACHE_WARMUPS + STATIC_CACHE_ROUNDS; $round++) {
        $sum = 0;
        $start = hrtime(true);
        for ($i = 0; $i < STATIC_CACHE_ITERATIONS; $i++) {
            $sum += StaticSlotData::$counter;
        }
        $elapsed = hrtime(true) - $start;
        if ($round >= STATIC_CACHE_WARMUPS && $elapsed < $best) {
            $best = $elapsed;
        }
        $checksum += $sum;
    }
    return [$best / STATIC_CACHE_ITERATIONS, $checksum];
}

function measureStaticCacheGetData(): array
{
    $best = PHP_FLOAT_MAX;
    $checksum = 0;
    for ($round = 0; $round < STATIC_CACHE_WARMUPS + STATIC_CACHE_ROUNDS; $round++) {
        $start = hrtime(true);
        for ($i = 0; $i < STATIC_CACHE_ITERATIONS; $i++) {
            StaticCacheData::getData();
        }
        $elapsed = hrtime(true) - $start;
        if ($round >= STATIC_CACHE_WARMUPS && $elapsed < $best) {
            $best = $elapsed;
        }
        $checksum += count(StaticCacheData::getData());
    }
    return [$best / STATIC_CACHE_ITERATIONS, $checksum];
}

function measureStaticCacheGetTable(): array
{
    $best = PHP_FLOAT_MAX;
    $checksum = 0;
    for ($round = 0; $round < STATIC_CACHE_WARMUPS + STATIC_CACHE_ROUNDS; $round++) {
        $start = hrtime(true);
        for ($i = 0; $i < STATIC_CACHE_ITERATIONS; $i++) {
            StaticCacheData::getTable();
        }
        $elapsed = hrtime(true) - $start;
        if ($round >= STATIC_CACHE_WARMUPS && $elapsed < $best) {
            $best = $elapsed;
        }
        $checksum += strlen(StaticCacheData::getTable());
    }
    return [$best / STATIC_CACHE_ITERATIONS, $checksum];
}

function main(): void
{
    StaticCacheData::getData();

    [$explicitRead, $explicitReadChecksum] = measureExplicitStaticRead();
    StaticSlotData::$counter = 1;
    [$selfRead, $selfReadChecksum] = StaticSlotData::measureSelfRead();
    [$selfWrite, $selfWriteChecksum] = StaticSlotData::measureSelfWrite();
    [$getData, $getDataChecksum] = measureStaticCacheGetData();
    [$getTable, $getTableChecksum] = measureStaticCacheGetTable();

    echo "explicit_read_ns={$explicitRead}\n";
    echo "self_read_ns={$selfRead}\n";
    echo "self_write_ns={$selfWrite}\n";
    echo "get_data_ns={$getData}\n";
    echo "get_table_ns={$getTable}\n";
    echo "checksum_explicit_read={$explicitReadChecksum}\n";
    echo "checksum_self_read={$selfReadChecksum}\n";
    echo "checksum_self_write={$selfWriteChecksum}\n";
    echo "checksum_get_data={$getDataChecksum}\n";
    echo "checksum_get_table={$getTableChecksum}\n";
}