<?php

declare(strict_types=1);

// Drop-in admin page for the host application.
//
// The host is expected to have established its own session and authentication
// BEFORE including this file. Adjust the default guard below to whatever the
// host project uses (see 02_INTEGRATION.md).
//
// Typical integration, as myproject/admin/manage.php:
//
//     require_once __DIR__ . "/../config.php";
//     require_once __DIR__ . "/../includes/functions.php";
//     if (empty($_SESSION["admin_logged_in"])) { header("Location: login.php"); exit; }
//     require __DIR__ . "/../manage-client/ui/panel.php";
//
// This page contains no update or backup logic of its own: every action calls
// the same public functions as the CLI.

require_once dirname(__DIR__) . "/lib/client.php";

if (session_status() === PHP_SESSION_NONE) {
    session_start();
}

// --- Authentication guard --------------------------------------------------
// Replace this block if the host application uses a different session flag.
if (!defined("MANAGE_PANEL_SKIP_AUTH_GUARD") && empty($_SESSION["admin_logged_in"])) {
    http_response_code(403);
    exit("Zugriff verweigert. Dieses Panel setzt eine angemeldete Sitzung voraus.");
}

function managePanelEscape($value): string
{
    return htmlspecialchars((string) $value, ENT_QUOTES | ENT_SUBSTITUTE, "UTF-8");
}

function managePanelCsrfToken(): string
{
    if (empty($_SESSION["manage_panel_csrf"])) {
        $_SESSION["manage_panel_csrf"] = bin2hex(random_bytes(32));
    }

    return (string) $_SESSION["manage_panel_csrf"];
}

function managePanelCsrfValid(string $token): bool
{
    return !empty($_SESSION["manage_panel_csrf"]) &&
        hash_equals((string) $_SESSION["manage_panel_csrf"], $token);
}

$messages = [];
$errors = [];
$warnings = [];

if (($_SERVER["REQUEST_METHOD"] ?? "") === "POST") {
    try {
        if (!managePanelCsrfValid((string) ($_POST["csrf_token"] ?? ""))) {
            throw new RuntimeException("Ungültiges Sicherheitstoken. Bitte die Seite neu laden.");
        }

        $action = (string) ($_POST["action"] ?? "");

        if ($action === "backup") {
            $record = manageBackupCreate("manual");
            $messages[] = "Backup erstellt: " . $record["filename"] .
                " (" . $record["file_count"] . " Dateien, " . manageFormatBytes((int) $record["size"]) . ")";
            foreach ($record["remote_uploads"] as $upload) {
                if (empty($upload["success"])) {
                    $warnings[] = "Upload an " . (string) $upload["target"] . " fehlgeschlagen: " .
                        (string) ($upload["error"] ?? "unbekannt");
                }
            }
            manageHeartbeatSendQuietly();
        } elseif ($action === "update") {
            $result = manageUpdateApply(["force" => !empty($_POST["force"])]);
            $messages[] = "Update ausgerollt: " . $result["from_version"] . " → " . $result["to_version"];
            $messages[] = $result["copied"] . " Dateien kopiert, " . $result["backed_up"] . " gesichert.";
            $messages[] = "Sicherungsverzeichnis: " . $result["backup_dir"];

            $hook = $result["hook"];
            if (is_array($hook)) {
                $applied = $hook["migrations"]["applied"] ?? [];
                if ($applied !== []) {
                    $messages[] = "Migrationen ausgeführt: " . implode(", ", $applied);
                }
                if (empty($hook["success"])) {
                    // The files are deployed; only the post-update step failed.
                    if (!empty($hook["failed_migration"])) {
                        $errors[] = "Die Dateien wurden ausgerollt, aber die Migration \"" .
                            (string) $hook["failed_migration"] . "\" ist fehlgeschlagen: " .
                            (string) ($hook["error"] ?? "");
                        $errors[] = "Verbleibende Migrationen wurden nicht ausgeführt. " .
                            "Nach Behebung der Ursache unten \"Migrationen ausführen\" verwenden.";
                    } else {
                        $errors[] = "Die Dateien wurden ausgerollt, aber der Post-Update-Hook ist " .
                            "fehlgeschlagen: " . (string) ($hook["error"] ?? "");
                    }
                }
            }
            manageHeartbeatSendQuietly();
        } elseif ($action === "migrate") {
            $report = manageUpdateRunMigrations();
            if ($report["applied"] !== []) {
                $messages[] = "Migrationen ausgeführt: " . implode(", ", $report["applied"]);
            }
            if (!$report["success"]) {
                $errors[] = "Migration \"" . (string) $report["failed"] . "\" ist fehlgeschlagen: " .
                    (string) $report["error"];
            } elseif ($report["applied"] === []) {
                $messages[] = "Keine offenen Migrationen.";
            }
        } elseif ($action === "heartbeat") {
            $result = manageHeartbeatSend();
            $messages[] = "Heartbeat gesendet. Aktuelles Release: " .
                ($result["latest"] !== "" ? $result["latest"] : "keines") . ".";
        } elseif ($action === "download") {
            $path = manageBackupPath((string) ($_POST["filename"] ?? ""));
            $size = filesize($path);
            $handle = fopen($path, "rb");
            if ($size === false || $handle === false) {
                throw new RuntimeException("Backup konnte nicht geöffnet werden.");
            }

            header("Content-Type: application/zip");
            header("Content-Disposition: attachment; filename=\"" . addcslashes(basename($path), "\"\\") . "\"");
            header("Content-Length: " . (string) $size);
            header("Cache-Control: private, no-store");
            header("X-Content-Type-Options: nosniff");
            fpassthru($handle);
            fclose($handle);
            exit;
        }
    } catch (Throwable $exception) {
        $errors[] = $exception->getMessage();
    }
}

$status = manageClientStatus();
$capabilities = manageRemoteCapabilities();

?>
<!DOCTYPE html>
<html lang="de">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Update &amp; Backup</title>
    <style>
        /* Self-contained so the panel looks reasonable in any host application.
           Override by loading the host's stylesheet after this file. */
        .mc-wrap { max-width: 60rem; margin: 0 auto; padding: 1.5rem 1rem 3rem;
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
            line-height: 1.55; color: #16191d; }
        .mc-wrap h1 { font-size: 1.5rem; margin: 0 0 1rem; }
        .mc-wrap h2 { font-size: 1.1rem; margin: 1.75rem 0 .75rem; }
        .mc-alert { padding: .7rem .9rem; border-radius: 8px; margin-bottom: .5rem; border: 1px solid transparent; }
        .mc-ok { background: #eaf6ee; border-color: #bfe0cb; color: #1a6b3c; }
        .mc-warn { background: #fdf3e0; border-color: #e6cf9d; color: #8a5a00; }
        .mc-err { background: #fceceb; border-color: #f0c3bf; color: #a52218; }
        .mc-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: .75rem; }
        .mc-card { border: 1px solid #d9dde3; border-radius: 8px; padding: .8rem .9rem; background: #fff; }
        .mc-label { font-size: .75rem; text-transform: uppercase; letter-spacing: .04em; color: #5c6470; }
        .mc-value { font-size: 1.2rem; font-weight: 600; }
        .mc-row { display: flex; flex-wrap: wrap; gap: .5rem; align-items: center; margin: .75rem 0; }
        .mc-btn { padding: .45rem .9rem; border: 1px solid #1f3b63; border-radius: 8px; background: #1f3b63;
            color: #fff; font: inherit; font-size: .9rem; cursor: pointer; }
        .mc-btn.sec { background: #fff; color: #1f3b63; }
        .mc-table { width: 100%; border-collapse: collapse; font-size: .9rem; }
        .mc-table th, .mc-table td { text-align: left; padding: .5rem .6rem; border-bottom: 1px solid #d9dde3; }
        .mc-table thead th { font-size: .75rem; text-transform: uppercase; color: #5c6470; }
        .mc-scroll { overflow-x: auto; border: 1px solid #d9dde3; border-radius: 8px; background: #fff; }
        .mc-muted { color: #5c6470; }
        .mc-mono { font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; font-size: .8rem; }
    </style>
</head>
<body>
<div class="mc-wrap">
    <h1>Update &amp; Backup</h1>

    <p><a href="settings.php">&larr; Zurück zu den Einstellungen</a></p>

    <?php foreach ($messages as $message): ?>
        <p class="mc-alert mc-ok"><?php echo managePanelEscape($message); ?></p>
    <?php endforeach; ?>
    <?php foreach ($warnings as $warning): ?>
        <p class="mc-alert mc-warn"><?php echo managePanelEscape($warning); ?></p>
    <?php endforeach; ?>
    <?php foreach ($errors as $error): ?>
        <p class="mc-alert mc-err"><?php echo managePanelEscape($error); ?></p>
    <?php endforeach; ?>

    <?php if (!$status["configured"]): ?>
        <p class="mc-alert mc-err">
            Der Manage-Client ist nicht konfiguriert. In <code>manage-client/config.php</code> müssen
            <code>MANAGE_SERVER_URL</code>, <code>MANAGE_INSTANCE</code> und <code>MANAGE_TOKEN</code> gesetzt sein.
        </p>
    <?php endif; ?>

    <div class="mc-grid">
        <div class="mc-card">
            <p class="mc-label">Installierte Version</p>
            <p class="mc-value"><?php echo managePanelEscape($status["version"] !== "" ? $status["version"] : "unbekannt"); ?></p>
        </div>
        <div class="mc-card">
            <p class="mc-label">Aktuelles Release</p>
            <p class="mc-value">
                <?php echo managePanelEscape($status["update"]["latest"] ?? "–"); ?>
            </p>
            <?php if ($status["update_error"] !== null): ?>
                <p class="mc-muted"><?php echo managePanelEscape($status["update_error"]); ?></p>
            <?php endif; ?>
        </div>
        <div class="mc-card">
            <p class="mc-label">Lokale Backups</p>
            <p class="mc-value"><?php echo count($status["backups"]); ?></p>
            <p class="mc-muted">Letztes: <?php echo managePanelEscape($status["last_backup_at"] ?? "nie"); ?></p>
        </div>
        <div class="mc-card">
            <p class="mc-label">Offene Migrationen</p>
            <p class="mc-value"><?php echo count($status["pending_migrations"]); ?></p>
        </div>
    </div>

    <?php if ($status["update"] !== null && $status["update"]["available"]): ?>
        <p class="mc-alert mc-warn">
            Version <?php echo managePanelEscape($status["update"]["latest"]); ?> steht bereit.
            Vor dem Ausrollen sollte ein aktuelles Backup vorliegen.
        </p>
    <?php endif; ?>

    <h2>Aktionen</h2>
    <div class="mc-row">
        <form method="POST">
            <input type="hidden" name="csrf_token" value="<?php echo managePanelEscape(managePanelCsrfToken()); ?>">
            <input type="hidden" name="action" value="backup">
            <button type="submit" class="mc-btn">Backup jetzt erstellen</button>
        </form>

        <form method="POST" onsubmit="return confirm('Update jetzt ausrollen? Dateien werden überschrieben.');">
            <input type="hidden" name="csrf_token" value="<?php echo managePanelEscape(managePanelCsrfToken()); ?>">
            <input type="hidden" name="action" value="update">
            <label class="mc-muted">
                <input type="checkbox" name="force" value="1"> erneut ausrollen
            </label>
            <button type="submit" class="mc-btn">Update ausrollen</button>
        </form>

        <?php if ($status["pending_migrations"] !== []): ?>
            <form method="POST">
                <input type="hidden" name="csrf_token" value="<?php echo managePanelEscape(managePanelCsrfToken()); ?>">
                <input type="hidden" name="action" value="migrate">
                <button type="submit" class="mc-btn sec">Migrationen ausführen</button>
            </form>
        <?php endif; ?>

        <form method="POST">
            <input type="hidden" name="csrf_token" value="<?php echo managePanelEscape(managePanelCsrfToken()); ?>">
            <input type="hidden" name="action" value="heartbeat">
            <button type="submit" class="mc-btn sec">Status melden</button>
        </form>
    </div>

    <?php if ($status["pending_migrations"] !== []): ?>
        <h2>Offene Migrationen</h2>
        <ul>
            <?php foreach ($status["pending_migrations"] as $migration): ?>
                <li class="mc-mono"><?php echo managePanelEscape($migration["id"]); ?></li>
            <?php endforeach; ?>
        </ul>
    <?php endif; ?>

    <h2>Lokale Backups</h2>
    <?php if ($status["backups"] === []): ?>
        <p class="mc-muted">Es wurde noch kein Backup erstellt.</p>
    <?php else: ?>
        <div class="mc-scroll">
            <table class="mc-table">
                <thead>
                <tr>
                    <th>Datei</th>
                    <th>Erstellt</th>
                    <th>Auslöser</th>
                    <th>Dateien</th>
                    <th>Größe</th>
                    <th>Upload</th>
                    <th></th>
                </tr>
                </thead>
                <tbody>
                <?php foreach ($status["backups"] as $backup): ?>
                    <tr>
                        <td class="mc-mono"><?php echo managePanelEscape($backup["filename"] ?? ""); ?></td>
                        <td><?php echo managePanelEscape($backup["created_at"] ?? ""); ?></td>
                        <td><?php echo managePanelEscape($backup["trigger"] ?? ""); ?></td>
                        <td><?php echo (int) ($backup["file_count"] ?? 0); ?></td>
                        <td><?php echo managePanelEscape(manageFormatBytes((int) ($backup["size"] ?? 0))); ?></td>
                        <td>
                            <?php
                            $uploads = is_array($backup["remote_uploads"] ?? null) ? $backup["remote_uploads"] : [];
                            if ($uploads === []) {
                                echo "–";
                            } else {
                                foreach ($uploads as $upload) {
                                    $ok = !empty($upload["success"]);
                                    echo managePanelEscape((string) ($upload["target"] ?? "?")) .
                                        ": " . ($ok ? "OK" : "Fehler") . "<br>";
                                }
                            }
                            ?>
                        </td>
                        <td>
                            <form method="POST">
                                <input type="hidden" name="csrf_token" value="<?php echo managePanelEscape(managePanelCsrfToken()); ?>">
                                <input type="hidden" name="action" value="download">
                                <input type="hidden" name="filename" value="<?php echo managePanelEscape($backup["filename"] ?? ""); ?>">
                                <button type="submit" class="mc-btn sec">Herunterladen</button>
                            </form>
                        </td>
                    </tr>
                <?php endforeach; ?>
                </tbody>
            </table>
        </div>
    <?php endif; ?>

    <?php
    $capabilityWarnings = [];
    foreach ($capabilities as $type => $capability) {
        if ($capability["configured"] && !$capability["available"]) {
            $capabilityWarnings[] = $type;
        }
    }
    ?>
    <?php if ($capabilityWarnings !== []): ?>
        <p class="mc-alert mc-warn">
            Konfigurierte Backup-Ziele ohne Systemunterstützung:
            <?php echo managePanelEscape(implode(", ", $capabilityWarnings)); ?>.
            Diese Uploads werden fehlschlagen.
        </p>
    <?php endif; ?>

    <?php foreach ($status["errors"] as $error): ?>
        <p class="mc-alert mc-warn"><?php echo managePanelEscape($error); ?></p>
    <?php endforeach; ?>
</div>
</body>
</html>