<?php

declare(strict_types=1);

namespace App\Application\LiveComponents\Dashboard;

use App\Framework\Core\ValueObjects\Byte;
use App\Framework\Core\ValueObjects\Percentage;
use App\Framework\DateTime\Clock;
use App\Framework\LiveComponents\Attributes\Action;
use App\Framework\LiveComponents\Attributes\LiveComponent;
use App\Framework\LiveComponents\Contracts\LiveComponentContract;
use App\Framework\LiveComponents\Contracts\Pollable;
use App\Framework\LiveComponents\ValueObjects\ComponentId;
use App\Framework\LiveComponents\ValueObjects\ComponentRenderData;
use App\Framework\Performance\MemoryMonitor;

/**
 * Performance Metrics LiveComponent
 *
 * Displays real-time performance metrics:
 * - Memory usage (current, peak, limit, percentage)
 * - Load average
 * - Execution time
 * - OPCache statistics
 *
 * Polls every 3 seconds for real-time monitoring.
 */
#[LiveComponent('performance-metrics')]
final readonly class PerformanceMetricsComponent implements LiveComponentContract, Pollable
{
    public function __construct(
        public ComponentId $id,
        public PerformanceMetricsState $state,
        private MemoryMonitor $memoryMonitor,
        private Clock $clock
    ) {}

    public function getRenderData(): ComponentRenderData
    {
        // Initial poll if state is empty (lastUpdated is empty string)
        $state = $this->state->lastUpdated === ''
            ? $this->poll()
            : $this->state;

        return new ComponentRenderData(
            templatePath: 'livecomponent-performance-metrics',
            data: [
                // LiveComponent integration
                'componentId' => $this->id->toString(),
                'stateJson' => json_encode($state->toArray()),
                'pollInterval' => $this->getPollInterval(),

                // Component data
                'currentMemory' => $state->currentMemory,
                'peakMemory' => $state->peakMemory,
                'memoryLimit' => $state->memoryLimit,
                'memoryUsagePercentage' => $state->memoryUsagePercentage,
                'loadAverage' => $state->loadAverage,
                'executionTime' => $state->executionTime,
                'includedFiles' => $state->includedFiles,
                'opcacheEnabled' => $state->opcacheEnabled,
                'opcacheMemoryUsage' => $state->opcacheMemoryUsage,
                'opcacheCacheHits' => $state->opcacheCacheHits,
                'opcacheMissRate' => $state->opcacheMissRate,
                'lastUpdated' => $state->lastUpdated,
            ]
        );
    }

    #[Action]
    public function poll(): PerformanceMetricsState
    {
        // Get memory metrics
        $currentMemory = $this->memoryMonitor->getCurrentMemory();
        $peakMemory = $this->memoryMonitor->getPeakMemory();
        $memoryLimit = $this->memoryMonitor->getMemoryLimit();
        $usagePercentage = $this->memoryMonitor->getMemoryUsagePercentage();

        // Get load average
        $loadAverage = function_exists('sys_getloadavg') ? sys_getloadavg() : ['N/A', 'N/A', 'N/A'];

        // Calculate execution time
        $executionTime = number_format(
            microtime(true) - ($_SERVER['REQUEST_TIME_FLOAT'] ?? microtime(true)),
            4
        ) . ' Sekunden';

        // Get included files count
        $includedFiles = count(get_included_files());

        // Check OPCache status
        $opcacheEnabled = function_exists('opcache_get_status');
        $opcacheMemoryUsage = null;
        $opcacheCacheHits = null;
        $opcacheMissRate = null;

        if ($opcacheEnabled) {
            try {
                $opcacheStatus = opcache_get_status(false);
                if ($opcacheStatus !== false) {
                    $memoryUsed = Byte::fromBytes($opcacheStatus['memory_usage']['used_memory']);
                    $opcacheMemoryUsage = $memoryUsed->toHumanReadable();
                    $opcacheCacheHits = number_format($opcacheStatus['opcache_statistics']['hits']);

                    $hits = $opcacheStatus['opcache_statistics']['hits'];
                    $misses = $opcacheStatus['opcache_statistics']['misses'];
                    $total = $hits + $misses;
                    if ($total > 0) {
                        $missRate = Percentage::from(($misses / $total) * 100);
                        $opcacheMissRate = $missRate->format(2) . '%';
                    }
                }
            } catch (\Throwable) {
                // Ignore errors
            }
        }

        return $this->state->withMetrics(
            currentMemory: $currentMemory->toHumanReadable(),
            peakMemory: $peakMemory->toHumanReadable(),
            memoryLimit: $memoryLimit->toHumanReadable(),
            memoryUsagePercentage: (float) $usagePercentage->format(2),
            loadAverage: $loadAverage,
            executionTime: $executionTime,
            includedFiles: $includedFiles,
            opcacheEnabled: $opcacheEnabled,
            opcacheMemoryUsage: $opcacheMemoryUsage,
            opcacheCacheHits: $opcacheCacheHits,
            opcacheMissRate: $opcacheMissRate
        );
    }

    public function getPollInterval(): int
    {
        return 3000; // Poll every 3 seconds for real-time updates
    }
}