<?php
/**
 * dashboard-api.php – Lazy-Load-Endpunkt für die Anreiseübersicht (tasks/dashboard).
 * Hinter dem PaCIM-Login. Liefert die nächste Charge an Tageskarten als HTML.
 *
 * GET offset, limit  -> { html, has_more, count }
 */
require_once( __DIR__ . "/includes/config.inc.php" );
@ini_set( 'display_errors', '0' );

if ( !isset( $_SESSION['user'] ) || $_SESSION['user'] != LOGIN_USER ) {
    http_response_code( 403 );
    echo 'unauthorized';
    exit();
}

global $smarty;
$dash   = new dashboard();
$action = isset( $_GET['action'] ) ? $_GET['action'] : '';
if ( class_exists( 'perflog' ) ) perflog::wholeRequest( 'dashboard', $action !== '' ? preg_replace( '/[^a-z_]/i', '', $action ) : '?', 'dashboard_ajax' );

// Monatsübersicht für den Kalender (Auslastung je Tag + Zusammenfassung)
if ( $action === 'month' ) {
    header( 'Content-Type: application/json; charset=utf-8' );
    echo json_encode( $dash->monthOverview(
        isset( $_GET['year'] )  ? (int) $_GET['year']  : (int) date('Y'),
        isset( $_GET['month'] ) ? (int) $_GET['month'] : (int) date('n')
    ) );
    exit();
}

// Rechte Tagesansicht als HTML (per AJAX beim Klick auf einen Kalendertag)
if ( $action === 'day' ) {
    header( 'Content-Type: text/html; charset=utf-8' );
    $date = ( isset( $_GET['date'] ) && preg_match( '/^\d{4}-\d{2}-\d{2}$/', $_GET['date'] ) ) ? $_GET['date'] : date('Y-m-d');
    $days = $dash->events( array( $date ) );
    $smarty->assign( 'day', !empty( $days ) ? $days[0] : false );
    $smarty->assign( 'dayDate', $date );
    echo $smarty->fetch( 'tasks/_day_detail.tpl' );
    exit();
}

// Fallback: bisheriger Lazy-Load der Tageskarten (JSON)
header( 'Content-Type: application/json; charset=utf-8' );
$offset = isset( $_GET['offset'] ) ? max( 0, (int) $_GET['offset'] ) : 0;
$limit  = isset( $_GET['limit'] )  ? min( 20, max( 1, (int) $_GET['limit'] ) ) : 5;
$dates  = $dash->eventDates( $offset, $limit );
$events = $dash->events( $dates );
$html = '';
foreach ( $events as $day ) {
    $smarty->assign( 'day', $day );
    $html .= $smarty->fetch( 'tasks/_event_card.tpl' );
}
echo json_encode( array(
    'html'     => $html,
    'count'    => count( $events ),
    'has_more' => count( $dates ) === $limit,
) );