<?php

// Prometheus metrics endpoint for temperatures.
$router->get('/metrics', function($req) use($db) {
    header('Content-Type: text/plain; charset=UTF-8');

    $results = $db->getDevices();

    // Print temperature metrics
    echo "# HELP temperature_celsius Temperature readings from the device\n";
    echo "# TYPE temperature_celsius gauge\n";
    foreach ($results as $index => $row) {
        $temperature = $row['temperature'];
        echo "temperature_celsius{device_id=\"{$row['id']}\"} $temperature\n";
    }

    // Print humidity metrics
    echo "# HELP relative_humidity_percent Humidity readings from the device\n";
    echo "# TYPE relative_humidity_percent gauge\n";
    foreach ($results as $index => $row) {
        $humidity = $row['humidity'];
        echo "relative_humidity_percent{device_id=\"{$row['id']}\"} $humidity\n";
    }

    http_response_code(200);
});