Add separate read-only ERP lager MCP

modules/erp/lager/mcp.php

@@ -0,0 +1,91 @@
+<?php
+declare(strict_types=1);
+
+require_once __DIR__ . '/service.php';
+
+function erp_lager_mcp_token(array $env): string
+{
+    $token = env_value('MARKET_MCP_TOKEN', $env);
+    if ($token === '') {
+        throw new RuntimeException('MARKET_MCP_TOKEN ist nicht konfiguriert.');
+    }
+
+    return $token;
+}
+
+function erp_lager_mcp_authorize(array $env): string
+{
+    $header = $_SERVER['HTTP_AUTHORIZATION'] ?? '';
+    if (!preg_match('/^Bearer\s+(.+)$/i', $header, $matches)) {
+        throw new RuntimeException('MCP Authorization Bearer Token fehlt.');
+    }
+
+    $token = trim($matches[1]);
+    if (!hash_equals(erp_lager_mcp_token($env), $token)) {
+        throw new RuntimeException('MCP Authorization Bearer Token ist ungültig.');
+    }
+
+    return 'hermes';
+}
+
+function erp_lager_mcp_tools(): array
+{
+    return [
+        [
+            'name' => 'erp_lager.list_products',
+            'description' => 'Aktive ERP-Lagerprodukte zur Ermittlung der Produkt-IDs lesen',
+            'inputSchema' => ['type' => 'object', 'properties' => []],
+        ],
+        [
+            'name' => 'erp_lager.get_product',
+            'description' => 'Produkt, aktuelle Lagermenge, Chargen und Ausverkaufsprognose lesen',
+            'inputSchema' => [
+                'type' => 'object',
+                'required' => ['product_id'],
+                'properties' => [
+                    'product_id' => ['type' => 'integer'],
+                ],
+            ],
+        ],
+    ];
+}
+
+function erp_lager_mcp_list_products(PDO $pdo): array
+{
+    return array_map(
+        static fn (array $product): array => [
+            'id' => $product['id'],
+            'name' => $product['name'],
+            'sku' => $product['sku'],
+            'uom' => $product['uom'],
+        ],
+        get_otc_order_form_products($pdo)
+    );
+}
+
+function erp_lager_mcp_get_product(PDO $pdo, int $productId): array
+{
+    if ($productId < 1) {
+        throw new InvalidArgumentException('product_id muss eine positive Ganzzahl sein.');
+    }
+
+    foreach (get_lager_product_overview($pdo) as $product) {
+        if ((int) $product['id'] === $productId) {
+            return $product;
+        }
+    }
+
+    throw new InvalidArgumentException('Aktives Lagerprodukt nicht gefunden.');
+}
+
+function erp_lager_mcp_call(PDO $pdo, string $tool, array $arguments): array
+{
+    return match ($tool) {
+        'erp_lager.list_products' => erp_lager_mcp_list_products($pdo),
+        'erp_lager.get_product' => erp_lager_mcp_get_product(
+            $pdo,
+            (int) ($arguments['product_id'] ?? 0)
+        ),
+        default => throw new InvalidArgumentException('Unbekanntes Lager-MCP-Tool: ' . $tool),
+    };
+}