add unique product path function when addProduct (#67)

* add unique product path function when addProduct

* refactor comments

src/datasources/product-api.ts

@@ -269,12 +269,50 @@ export class ProductAPI extends BaseSQLDataSource {
     );
   }
 
+  async getUniqueProductSlug(slug: string): Promise<string> {
+    // Check for unique-slug
+    // Get paths from product-products
+    const pathResponse = await this.knex.raw(
+      `SELECT path FROM "product-products" WHERE path LIKE ?`,
+      [slug + '%'],
+    );
+    const paths = pathResponse.rows.map((item) => item.path);
+
+    // Evaluate new pathname
+    let newSlug = '';
+    // If the exact match of the slug is not listed
+    // in the paths queried from db. Then use the
+    // tested slug.
+    if (!paths.includes(slug)) {
+      newSlug = slug;
+    } else {
+      // Try to find any numbers in the pathname
+      const numbers = paths
+        .map((path) => {
+          return parseInt(path.replace(slug + '-', ''));
+        })
+        .filter(Boolean); // Remove falsy
+      if (numbers.length === 0) {
+        // No numbers found, add 1.
+        newSlug = slug + '-1';
+      } else {
+        // Get highest number + 1
+        const next = Math.max(...numbers) + 1;
+        newSlug = slug + '-' + next;
+      }
+    }
+    return newSlug;
+  }
+
   async addProduct(name: string, batch: string): Promise<number> {
     const path = batch ? batch + ' ' + name : name;
+    const productSlug = slug(path);
+    const safeSlug = await this.getUniqueProductSlug(productSlug);
+
     const idres = await this.knex
       .table('product-products')
       .insert({
-        path: slug(path),
+        path: slug(safeSlug),
         browsable: 0,
         visible: 0,
       })