<?php

require_once 'includes/functions.php';
require_once 'config.php';

/**
 *
 */
function DisplaySystem(&$extraFooterScripts)
{
    $status = new \RaspAP\Messages\StatusMessage;

    if (isset($_POST['SaveLanguage'])) {
        if (isset($_POST['locale'])) {
            $_SESSION['locale'] = $_POST['locale'];
            $status->addMessage('Language setting saved', 'success');
        }
    }

    if (!RASPI_MONITOR_ENABLED) {
        if (isset($_POST['SaveServerSettings'])) {
            $good_input = true;
            // Validate server port
            if (isset($_POST['serverPort'])) {
                if (strlen($_POST['serverPort']) > 4 || !is_numeric($_POST['serverPort'])) {
                    $status->addMessage('Invalid value for port number', 'danger');
                    $good_input = false;
                } else {
                    $serverPort = escapeshellarg($_POST['serverPort']);
               }
            }
            // Validate server bind address
            $serverBind = escapeshellarg('');
            if ($_POST['serverBind'] && $_POST['serverBind'] !== null ) {
                if (!filter_var($_POST['serverBind'], FILTER_VALIDATE_IP)) {
                    $status->addMessage('Invalid value for bind address', 'danger');
                    $good_input = false;
                } else {
                    $serverBind = escapeshellarg($_POST['serverBind']);
                }
            }
            // Validate log limit
            if (isset($_POST['logLimit'])) {
                if ( strlen($_POST['logLimit']) > 4 || !is_numeric($_POST['logLimit']) ) {
                    $status->addMessage('Invalid value for log size limit', 'danger');
                    $good_input = false;
                } else {
                    $_SESSION['log_limit'] = intval($_POST['logLimit']);
                    $status->addMessage(sprintf(_('Changing log limit size to %s KB'), $_SESSION['log_limit']), 'info');
                }
            }
            // Save settings
            if ($good_input) {
                exec("sudo /etc/raspap/lighttpd/configport.sh $serverPort $serverBind " .RASPI_LIGHTTPD_CONFIG. " ".$_SERVER['SERVER_NAME'], $return);
                foreach ($return as $line) {
                    $status->addMessage($line, 'info');
                }
            }
        }
    }

    if (isset($_POST['RestartLighttpd'])) {
        $status->addMessage('Restarting lighttpd in 3 seconds...', 'info');
        exec('sudo /etc/raspap/lighttpd/configport.sh --restart');
    }
    exec('cat '. RASPI_LIGHTTPD_CONFIG, $return);
    $conf = ParseConfig($return);
    $serverPort = $conf['server.port'];
    if (isset($conf['server.bind'])) {
        $serverBind = str_replace('"', '',$conf['server.bind']);
    } else {
        $serverBind = '';
    }

    // define locales
    $arrLocales = getLocales();

    // fetch system status variables
    $system = new \RaspAP\System\Sysinfo;

    $hostname = $system->hostname();
    $uptime   = $system->uptime();
    $cores    = $system->processorCount();
    $os       = $system->operatingSystem();
    $kernel   = $system->kernelVersion();
    $systime  = $system->systime();
    $revision = $system->rpiRevision();

    // memory use
    $memused  = $system->usedMemory();
    $memStatus = getMemStatus($memused);
    $memused_status = $memStatus['status'];
    $memused_led = $memStatus['led'];

    // cpu load
    $cpuload = $system->systemLoadPercentage();
    $cpuload_status = getCPULoadStatus($cpuload);

    // cpu temp
    $cputemp = $system->systemTemperature();
    $cpuStatus = getCPUTempStatus($cputemp);
    $cputemp_status = $cpuStatus['status'];
    $cputemp_led =  $cpuStatus['led'];

    // theme options
    $themes = [
        "default"    => "RaspAP (default)",
        "hackernews" => "HackerNews",
    ];
    $themeFiles = [
        "default"    => "custom.php",
        "hackernews" => "hackernews.css",
    ];
    $selectedTheme = array_search($_COOKIE['theme'], $themeFiles);
    $extraFooterScripts[] = array('src'=>'dist/huebee/huebee.pkgd.min.js', 'defer'=>false);
    $extraFooterScripts[] = array('src'=>'app/js/huebee.js', 'defer'=>false);
    $logLimit = isset($_SESSION['log_limit']) ? $_SESSION['log_limit'] : RASPI_LOG_SIZE_LIMIT;

    $plugins = getUserPlugins();
    $pluginsTable = getHTMLPluginsTable($plugins);

    echo renderTemplate("system", compact(
        "arrLocales",
        "status",
        "serverPort",
        "serverBind",
        "hostname",
        "uptime",
        "systime",
        "revision",
        "cores",
        "os",
        "kernel",
        "memused",
        "memused_status",
        "memused_led",
        "cpuload",
        "cpuload_status",
        "cputemp",
        "cputemp_status",
        "cputemp_led",
        "themes",
        "selectedTheme",
        "logLimit",
        "pluginsTable"
    ));
}

/**
 * Returns user plugin details from associated manifest.json files
 *
 * @return array $plugins
 */
function getUserPlugins()
{
    $pluginInstaller = \RaspAP\Plugins\PluginInstaller::getInstance();
    $installedPlugins = $pluginInstaller->getPlugins();

    try {
        $submodules = getSubmodules(RASPI_PLUGINS_URL);
        $plugins = [];
        foreach ($submodules as $submodule) {
            $manifestUrl = $submodule['url'] .'/blob/master/manifest.json?raw=true';
            $manifest = getPluginManifest($manifestUrl);

            if ($manifest) {
                $namespace = $manifest['namespace'] ?? '';
                $installed = false;

                foreach ($installedPlugins as $plugin) {
                    if (str_contains($plugin, $namespace)) {
                        $installed = true;
                        break;
                    }
                }

                $plugins[] = [
                    'version' => $manifest['version'] ?? 'unknown',
                    'name' => $manifest['name'] ?? 'unknown',
                    'description' => $manifest['description'] ?? 'No description provided',
                    'plugin_uri' => $manifest['plugin_uri'] ?? $submodule['url'],
                    'namespace' => $namespace,
                    'fa-icon' => $manifest['icon'] ?? 'fas fa-plug',
                    'installed' => $installed
                ];
            }
        }
        return $plugins;
    } catch (Exception $e) {
        echo "An error occured: " .$e->getMessage();
    }
}

/**
 * Returns git submodules for the specified repository
 *
 * @param string $repoURL
 * @return array $submodules
 */
function getSubmodules(string $repoUrl): array
{
    $gitmodulesUrl = $repoUrl . '/refs/heads/master/.gitmodules';
    $gitmodulesContent = file_get_contents($gitmodulesUrl);

    if ($gitmodulesContent === false) {
        throw new Exception('Unable to fetch .gitmodules file from the repository');
    }

    $submodules = [];
    $lines = explode("\n", $gitmodulesContent);
    $currentSubmodule = [];

    foreach ($lines as $line) {
        $line = trim($line);

        if (strpos($line, '[submodule "') === 0) {
            if (!empty($currentSubmodule)) {
                $submodules[] = $currentSubmodule;
            }
            $currentSubmodule = [];
        } elseif (strpos($line, 'path = ') === 0) {
            $currentSubmodule['path'] = substr($line, strlen('path = '));
        } elseif (strpos($line, 'url = ') === 0) {
            $currentSubmodule['url'] = substr($line, strlen('url = '));
        }
    }

    if (!empty($currentSubmodule)) {
        $submodules[] = $currentSubmodule;
    }

    return $submodules;
}

/**
 * Decodes a plugin's associated manifest JSON.
 * Returns an array of key-value pairs
 *
 * @param string $url
 * @return array $json
 */
function getPluginManifest(string $url): ?array
{
    $options = [
        'http' => [
            'method' => 'GET',
            'follow_location' => 1,
        ],
    ];

    $context = stream_context_create($options);
    $content = file_get_contents($url, false, $context);

    if ($content === false) {
        return null;
    }
    $json = json_decode($content, true);

    if (json_last_error() !== JSON_ERROR_NONE) {
        return null;
    }
    return $json;
}

/**
 * Returns a list of available plugins formatted as an HTML table
 *
 * @param array $plugins
 * @return string $html
 */
function getHTMLPluginsTable(array $plugins): string
{
    $html = '<table class="table table-striped table-hover">';
    $html .= '<thead><tr>';
    $html .= '<th scope="col">Name</th>';
    $html .= '<th scope="col">Version</th>';
    $html .= '<th scope="col">Description</th>';
    $html .= '<th scope="col"></th>';
    $html .= '</tr></thead></tbody>';

    foreach ($plugins as $plugin) {
        $installed = $plugin['installed'];
        if ($installed === true ) {
            $status = 'Installed';
        } else {
            $status = '<button type="button" class="btn btn-outline btn-primary btn-sm text-nowrap"
                name="install-plugin" data-bs-toggle="modal" data-bs-target="#installPlugin" />'
                . _("Install now") .'</button>';
        }
        $name = '<i class="' . htmlspecialchars($plugin['fa-icon']) . ' link-secondary me-2"></i><a href="'
            . htmlspecialchars($plugin['plugin_uri'])
            . '" target="_blank">'
            . htmlspecialchars($plugin['name']). '</a>';
        $html .= '<tr><td>' .$name. '</td>';
        $html .= '<td>' .htmlspecialchars($plugin['version']). '</td>';
        $html .= '<td>' .htmlspecialchars($plugin['description']). '</td>';
        $html .= '<td>' .$status. '</td>';
    }
    $html .= '</tbody></table>';
    return $html;
}

function getMemStatus($memused): array
{
    $memused_status = "primary";
    $memused_led = "";

    if ($memused > 90) {
        $memused_status = "danger";
        $memused_led = "service-status-down";
    } elseif ($memused > 75) {
        $memused_status = "warning";
        $memused_led = "service-status-warn";
    } elseif ($memused > 0) {
        $memused_status = "success";
        $memused_led = "service-status-up";
    }

    return [
        'status' => $memused_status,
        'led' => $memused_led
    ];
}

function getCPULoadStatus($cpuload): string
{
    if ($cpuload > 90) {
        $status = "danger";
    } elseif ($cpuload > 75) {
        $status = "warning";
    } elseif ($cpuload >=  0) {
        $status = "success";
    }
    return $status;
}

function getCPUTempStatus($cputemp): array
{
    if ($cputemp > 70) {
        $cputemp_status = "danger";
        $cputemp_led = "service-status-down";
    } elseif ($cputemp > 50) {
        $cputemp_status = "warning";
        $cputemp_led = "service-status-warn";
    } else {
        $cputemp_status = "success";
        $cputemp_led = "service-status-up";
    }
    return [
        'status' => $cputemp_status,
        'led' => $cputemp_led
    ];
}