feat: Working on search for purchase orders.

Sources/DatabaseClientLive/PurchaseOrders.swift

@@ -29,10 +29,42 @@ public extension DatabaseClient.PurchaseOrders {
         throw NotFoundError()
       }
       try await model.delete(on: database)
+    } search: { search in
+      let query = PurchaseOrderModel.allQuery(on: database)
+
+      switch search {
+      case let .employee(employee):
+        guard let employee = try await EmployeeModel.query(on: database).group(.or, { group in
+          group.filter(\.$firstName ~~ employee).filter(\.$lastName ~~ employee)
+        }).first()
+        else { return Page<PurchaseOrder>.empty }
+
+        return try await query.filter(\.$createdFor.$id == employee.id!)
+          .paginate(.init(page: 1, per: 25))
+          .map { try $0.toDTO() }
+
+      case let .customer(search):
+        return try await query.filter(\.$customer ~~ search)
+          .paginate(.init(page: 1, per: 25))
+          .map { try $0.toDTO() }
+
+      case let .vendor(search):
+        guard let vendor = try await VendorModel.query(on: database).filter(\.$name ~~ search).first() else {
+          return .empty
+        }
+        // TODO: how to search for this??
+        return .init(items: [], metadata: .init(page: 1, per: 1, total: 0))
+      }
     }
   }
 }
 
+private extension Page where T == PurchaseOrder {
+  static var empty: Self {
+    .init(items: [], metadata: .init(page: 1, per: 1, total: 0))
+  }
+}
+
 extension PurchaseOrder {
   struct Migrate: AsyncMigration {