add structure

lib/model/constants.dart

@@ -0,0 +1,37 @@
+const ok_doc_id = "ok";
+const setting_doc_id = "ok_setting";
+
+const config_collection = "configs";
+const biz_collection = "bizs";
+const product_collection = "products";
+const user_collection = "users";
+const privilege_collection = "privileges";
+const user_level_collection = "user_levels";
+const storage_collection = "storages";
+const buyer_collection = "buyers";
+const buying_pos = "buying_pos";
+const selling_pos = "selling_pos";
+const inventory_takings = "inventory_takings";
+const inventory_lines = "inventory_lines";
+const pds_collection = "pds";
+const pos_collection = "pos";
+const dos_collection = "dos";
+const notification_collection = "notifications";
+const log_collection = "logs";
+const report_collection = "reports";
+const po_product_collection = "po_products";
+const device_collection = "devices";
+const do_po_lines_collection = "do_po_lines";
+const reports_collection = "reports";
+const announcement_collection = "announcements";
+const report_user_collection = "report_users";
+
+const po_files_path = "/ok/po";
+const reg_files_path = "/ok/reg";
+const do_files_path = "/ok/do";
+const sign_files_path = "/ok/sign";
+const bank_images_path = "/ok/banks";
+
+const po_approved_status = "approved";
+const po_closed_status = "closed";
+const do_approved_status = "approved";