<?php

declare(strict_types=1);

/**
 * Performance Profiling Usage Examples
 *
 * Dieses Script demonstriert die Verwendung des NestedPerformanceTracker
 * für Flamegraph-Visualisierung und Timeline-Analyse.
 *
 * Ausführung: php examples/performance-profiling-usage.php
 */

require_once __DIR__ . '/../vendor/autoload.php';

use App\Framework\Performance\NestedPerformanceTracker;
use App\Framework\Performance\PerformanceCategory;
use App\Framework\DateTime\SystemClock;
use App\Framework\DateTime\SystemHighResolutionClock;
use App\Framework\Performance\MemoryMonitor;

// Tracker initialisieren
$tracker = new NestedPerformanceTracker(
    new SystemClock(),
    new SystemHighResolutionClock(),
    new MemoryMonitor()
);

echo "=== Performance Profiling Examples ===\n\n";

// Example 1: Einfache verschachtelte Operationen
echo "Example 1: Nested Operations\n";
echo str_repeat('-', 50) . "\n";

$tracker->measure(
    'http.request',
    PerformanceCategory::CONTROLLER,
    function () use ($tracker) {
        usleep(5000); // 5ms Controller-Logik

        // Database Query
        $tracker->measure(
            'database.query',
            PerformanceCategory::DATABASE,
            function () {
                usleep(10000); // 10ms Query
                return ['users' => 100];
            }
        );

        // Cache Operation
        $tracker->measure(
            'cache.get',
            PerformanceCategory::CACHE,
            function () {
                usleep(2000); // 2ms Cache
                return ['cached' => true];
            }
        );

        // Template Rendering
        $tracker->measure(
            'template.render',
            PerformanceCategory::VIEW,
            function () use ($tracker) {
                usleep(3000); // 3ms Template

                // Nested: Asset Loading
                $tracker->measure(
                    'assets.load',
                    PerformanceCategory::FILESYSTEM,
                    function () {
                        usleep(1000); // 1ms Assets
                    }
                );
            }
        );

        return ['status' => 'success'];
    }
);

// Flamegraph generieren
echo "\nFlamegraph Data:\n";
$flamegraph = $tracker->generateFlamegraph();

foreach ($flamegraph as $entry) {
    echo sprintf(
        "  %s → %.2f samples\n",
        $entry['stack_trace'],
        $entry['samples']
    );
}

// Timeline generieren
echo "\nTimeline Events:\n";
$timeline = $tracker->generateTimeline();

foreach ($timeline as $event) {
    $indent = str_repeat('  ', $event['depth']);
    echo sprintf(
        "  %s[%s] %s (%.2fms self, %.2fms total, %.2fMB memory)\n",
        $indent,
        $event['category'],
        $event['name'],
        $event['self_time_ms'],
        $event['duration_ms'],
        $event['memory_delta_mb']
    );
}

// Summary
echo "\nPerformance Summary:\n";
$summary = $tracker->getSummary();
foreach ($summary as $key => $value) {
    echo sprintf("  %s: %s\n", $key, is_float($value) ? number_format($value, 2) : $value);
}

echo "\n" . str_repeat('=', 50) . "\n\n";

// Example 2: Flamegraph Export für Visualisierung
echo "Example 2: Flamegraph Export (Brendan Gregg Format)\n";
echo str_repeat('-', 50) . "\n";

$tracker->reset(); // Reset für neues Beispiel

// Komplexere Operation
$tracker->measure(
    'api.request',
    PerformanceCategory::API,
    function () use ($tracker) {
        usleep(2000);

        // Service Layer
        $tracker->measure(
            'service.process',
            PerformanceCategory::CUSTOM,
            function () use ($tracker) {
                usleep(5000);

                // Repository
                $tracker->measure(
                    'repository.find',
                    PerformanceCategory::DATABASE,
                    function () {
                        usleep(8000);
                    }
                );

                // Cache
                $tracker->measure(
                    'cache.set',
                    PerformanceCategory::CACHE,
                    function () {
                        usleep(3000);
                    }
                );
            }
        );

        // Response Transformation
        $tracker->measure(
            'transformer.transform',
            PerformanceCategory::CUSTOM,
            function () {
                usleep(4000);
            }
        );
    }
);

$flamegraphData = $tracker->generateFlamegraph();

echo "\nFlamegraph Format für flamegraph.pl:\n";
echo "----------------------------------------\n";

foreach ($flamegraphData as $entry) {
    echo sprintf(
        "%s %d\n",
        $entry['stack_trace'],
        (int) ceil($entry['samples'])
    );
}

// In Datei schreiben für flamegraph.pl Tool
$flamegraphFile = __DIR__ . '/../tests/tmp/flamegraph.txt';
@mkdir(dirname($flamegraphFile), 0755, true);

$output = [];
foreach ($flamegraphData as $entry) {
    $output[] = sprintf(
        "%s %d",
        $entry['stack_trace'],
        (int) ceil($entry['samples'])
    );
}

file_put_contents($flamegraphFile, implode("\n", $output));
echo "\nFlamegraph data saved to: {$flamegraphFile}\n";
echo "Generate SVG: flamegraph.pl {$flamegraphFile} > flamegraph.svg\n";

echo "\n" . str_repeat('=', 50) . "\n\n";

// Example 3: Chrome DevTools Timeline Export
echo "Example 3: Chrome DevTools Timeline Export\n";
echo str_repeat('-', 50) . "\n";

$timeline = $tracker->generateTimeline();

// In Chrome Trace Event Format konvertieren
$traceEvents = [];

foreach ($timeline as $event) {
    // Begin Event
    $traceEvents[] = [
        'name' => $event['name'],
        'cat' => $event['category'],
        'ph' => 'B', // Begin
        'ts' => (int)($event['start_time'] * 1_000_000), // Microseconds
        'pid' => 1,
        'tid' => 1,
        'args' => $event['context']
    ];

    // End Event
    $traceEvents[] = [
        'name' => $event['name'],
        'cat' => $event['category'],
        'ph' => 'E', // End
        'ts' => (int)($event['end_time'] * 1_000_000),
        'pid' => 1,
        'tid' => 1
    ];
}

$chromeTrace = [
    'traceEvents' => $traceEvents,
    'displayTimeUnit' => 'ms',
    'otherData' => [
        'version' => '1.0',
        'framework' => 'Custom PHP Framework'
    ]
];

$chromeTraceFile = __DIR__ . '/../tests/tmp/chrome-trace.json';
file_put_contents($chromeTraceFile, json_encode($chromeTrace, JSON_PRETTY_PRINT));

echo "\nChrome Trace saved to: {$chromeTraceFile}\n";
echo "Open in Chrome: chrome://tracing → Load → {$chromeTraceFile}\n";

echo "\n" . str_repeat('=', 50) . "\n\n";

// Example 4: Performance Budget Validation
echo "Example 4: Performance Budget Validation\n";
echo str_repeat('-', 50) . "\n";

$budgets = [
    'database.query' => 5,   // max 5ms
    'cache.get' => 1,        // max 1ms
    'api.request' => 20,     // max 20ms
];

$violations = [];

foreach ($timeline as $event) {
    // Check ob Operation ein Budget hat
    foreach ($budgets as $operation => $budget) {
        if (str_contains($event['name'], $operation)) {
            if ($event['duration_ms'] > $budget) {
                $violations[] = [
                    'operation' => $event['name'],
                    'duration' => $event['duration_ms'],
                    'budget' => $budget,
                    'exceeded_by' => $event['duration_ms'] - $budget,
                    'exceeded_percentage' => (($event['duration_ms'] - $budget) / $budget) * 100
                ];
            }
        }
    }
}

if (!empty($violations)) {
    echo "\n⚠️  Performance Budget Violations:\n";
    foreach ($violations as $violation) {
        echo sprintf(
            "  • %s: %.2fms (budget: %.2fms, exceeded by %.2fms / %.1f%%)\n",
            $violation['operation'],
            $violation['duration'],
            $violation['budget'],
            $violation['exceeded_by'],
            $violation['exceeded_percentage']
        );
    }
} else {
    echo "\n✅ All operations within performance budget!\n";
}

echo "\n" . str_repeat('=', 50) . "\n\n";

// Example 5: Bottleneck Detection
echo "Example 5: Automatic Bottleneck Detection\n";
echo str_repeat('-', 50) . "\n";

// Sortiere nach self_time_ms (Zeit ohne Children)
$timelineCopy = $timeline;
usort($timelineCopy, fn($a, $b) => $b['self_time_ms'] <=> $a['self_time_ms']);

// Top 3 Bottlenecks
$bottlenecks = array_slice($timelineCopy, 0, 3);

echo "\nTop 3 Performance Bottlenecks (by self-time):\n";

foreach ($bottlenecks as $index => $bottleneck) {
    $percentage = ($bottleneck['self_time_ms'] / $bottleneck['duration_ms']) * 100;

    echo sprintf(
        "  %d. %s [%s]\n" .
        "     Self Time: %.2fms (%.1f%% of total %.2fms)\n" .
        "     Memory: %.2fMB\n" .
        "     Depth: %d\n",
        $index + 1,
        $bottleneck['name'],
        $bottleneck['category'],
        $bottleneck['self_time_ms'],
        $percentage,
        $bottleneck['duration_ms'],
        $bottleneck['memory_delta_mb'],
        $bottleneck['depth']
    );
}

echo "\n" . str_repeat('=', 50) . "\n\n";

// Example 6: Memory Usage Analysis
echo "Example 6: Memory Usage Analysis\n";
echo str_repeat('-', 50) . "\n";

$totalMemory = 0;
$memoryByCategory = [];

foreach ($timeline as $event) {
    $totalMemory += $event['memory_delta_mb'];

    $category = $event['category'];
    if (!isset($memoryByCategory[$category])) {
        $memoryByCategory[$category] = 0;
    }
    $memoryByCategory[$category] += $event['memory_delta_mb'];
}

echo sprintf("\nTotal Memory Delta: %.2fMB\n", $totalMemory);
echo "\nMemory Usage by Category:\n";

arsort($memoryByCategory);
foreach ($memoryByCategory as $category => $memory) {
    $percentage = ($memory / max($totalMemory, 0.001)) * 100;
    echo sprintf(
        "  • %s: %.2fMB (%.1f%%)\n",
        $category,
        $memory,
        $percentage
    );
}

// High memory operations
$highMemoryOps = array_filter($timeline, fn($e) => $e['memory_delta_mb'] > 0.5);

if (!empty($highMemoryOps)) {
    echo "\n⚠️  High Memory Operations (>0.5MB):\n";
    foreach ($highMemoryOps as $op) {
        echo sprintf(
            "  • %s: %.2fMB\n",
            $op['name'],
            $op['memory_delta_mb']
        );
    }
}

echo "\n" . str_repeat('=', 50) . "\n\n";

echo "✅ Performance Profiling Examples completed!\n\n";
echo "Generated Files:\n";
echo "  • {$flamegraphFile}\n";
echo "  • {$chromeTraceFile}\n\n";

echo "Next Steps:\n";
echo "  1. Generate SVG: flamegraph.pl {$flamegraphFile} > flamegraph.svg\n";
echo "  2. View in Chrome: chrome://tracing → Load {$chromeTraceFile}\n";
echo "  3. Integrate into API endpoints for production monitoring\n\n";