<?php

declare(strict_types=1);

require_once __DIR__ . '/bootstrap.php';

function outputCustomerLogo(PDO $pdo, int $id): void
{
    $statement = $pdo->prepare(
        'SELECT logo_blob, logo_mime_type, updated_at
         FROM customer_references
         WHERE id = ? AND is_active = 1 AND logo_blob IS NOT NULL
         LIMIT 1'
    );
    $statement->execute([$id]);
    $logo = $statement->fetch();
    $allowed = ['image/png', 'image/jpeg', 'image/webp', 'image/gif'];
    if (!$logo || !is_string($logo['logo_blob'])) {
        http_response_code(404);
        exit;
    }
    $mime = (string)($logo['logo_mime_type'] ?? '');
    if (!in_array($mime, $allowed, true)) {
        http_response_code(415);
        exit;
    }
    $etag = '"' . sha1((string)$logo['updated_at'] . ':' . strlen($logo['logo_blob'])) . '"';
    if (trim((string)($_SERVER['HTTP_IF_NONE_MATCH'] ?? '')) === $etag) {
        http_response_code(304);
        exit;
    }
    header('Content-Type: ' . $mime);
    header('Content-Length: ' . strlen($logo['logo_blob']));
    header('Cache-Control: public, max-age=3600');
    header('ETag: ' . $etag);
    header('X-Content-Type-Options: nosniff');
    echo $logo['logo_blob'];
    exit;
}

function outputCachedCustomerLogo(int $id): void
{
    $types = ['png' => 'image/png', 'jpg' => 'image/jpeg', 'webp' => 'image/webp', 'gif' => 'image/gif'];
    foreach ($types as $extension => $mime) {
        $path = __DIR__ . '/content-cache-logos/' . $id . '.' . $extension;
        if (!is_file($path)) {
            continue;
        }
        header('Content-Type: ' . $mime);
        header('Content-Length: ' . filesize($path));
        header('Cache-Control: public, max-age=3600');
        header('X-Content-Type-Options: nosniff');
        readfile($path);
        exit;
    }
    http_response_code(404);
    exit;
}

function cachedContent(): ?array
{
    $path = __DIR__ . '/content-cache.json';
    if (!is_file($path)) {
        return null;
    }
    $decoded = json_decode((string)file_get_contents($path), true);
    return is_array($decoded) ? $decoded : null;
}

if (isset($_GET['logo'])) {
    $logoId = filter_input(INPUT_GET, 'logo', FILTER_VALIDATE_INT, ['options' => ['min_range' => 1]]);
    if (!$logoId) {
        http_response_code(400);
        exit;
    }
    try {
        outputCustomerLogo(bmc_db(), $logoId);
    } catch (Throwable $e) {
        outputCachedCustomerLogo($logoId);
    }
}

function fetchCustomers(PDO $pdo): array
{
    $sql = "SELECT customer_name, logo_url, website_url
            FROM customer_references
            WHERE is_active = 1
            ORDER BY sort_order ASC, customer_name ASC
            LIMIT 50";

    return $pdo->query($sql)->fetchAll();
}

function fetchCurrentOperation(PDO $pdo): ?array
{
    $sql = "SELECT title, severity, message, starts_at, ends_at, updated_at
            FROM operations_status
            WHERE is_active = 1
              AND (starts_at IS NULL OR starts_at <= NOW())
              AND (ends_at IS NULL OR ends_at >= NOW())
            ORDER BY updated_at DESC
            LIMIT 1";

    $row = $pdo->query($sql)->fetch();
    return $row ?: null;
}

function fetchOperationHistory(PDO $pdo): array
{
    $sql = "SELECT title, severity, message, starts_at, ends_at, updated_at
            FROM operations_incidents
            WHERE is_public = 1
            ORDER BY updated_at DESC
            LIMIT 20";

    return $pdo->query($sql)->fetchAll();
}

try {
    $pdo = bmc_db();

    $customers = [];
    $current = null;
    $history = [];

    try {
        $customers = fetchCustomers($pdo);
    } catch (Throwable $e) {
        $customers = [];
    }

    try {
        $current = fetchCurrentOperation($pdo);
    } catch (Throwable $e) {
        $current = null;
    }

    try {
        $history = fetchOperationHistory($pdo);
    } catch (Throwable $e) {
        $history = [];
    }

    bmc_json_response([
        'meta' => [
            'generated_at' => gmdate('c'),
        ],
        'customers' => $customers,
        'operations' => [
            'current' => $current,
            'history' => $history,
        ],
    ]);
} catch (Throwable $e) {
    $cached = cachedContent();
    if ($cached !== null) {
        bmc_json_response($cached);
    }
    bmc_json_response([
        'error' => 'content_unavailable',
        'message' => 'Kunne ikke hente dynamisk indhold.',
    ], 503);
}