From 64f6f70e65c2e7114b4a040d6583e1f69cf6fc63 Mon Sep 17 00:00:00 2001
From: Maksym Sadovnychyy <hailstrike@hotmail.com>
Date: Sun, 6 Oct 2024 00:48:33 +0200
Subject: [PATCH] (bugfix): upsert and update many logics

---
 .../BaseCollectionDataProviderBase.cs         | 57 +++++++++++++------
 .../MaksIT.MongoDB.Linq.csproj                |  2 +-
 2 files changed, 42 insertions(+), 17 deletions(-)

diff --git a/src/MaksIT.MongoDB.Linq/Abstractions/BaseCollectionDataProviderBase.cs b/src/MaksIT.MongoDB.Linq/Abstractions/BaseCollectionDataProviderBase.cs
index 61f4ee5..f63ab7b 100644
--- a/src/MaksIT.MongoDB.Linq/Abstractions/BaseCollectionDataProviderBase.cs
+++ b/src/MaksIT.MongoDB.Linq/Abstractions/BaseCollectionDataProviderBase.cs
@@ -89,14 +89,37 @@ namespace MaksIT.MongoDB.Linq.Abstractions {
         Expression<Func<TDtoDocument, bool>> predicate,
         IClientSessionHandle? session) {
       try {
-        foreach (var document in documents) {
-          if (session != null)
-            await Collection.ReplaceOneAsync(session, predicate, document);
-          else
-            await Collection.ReplaceOneAsync(predicate, document);
+        // Step 1: Find the documents that already exist based on the predicate
+        List<TDtoDocument> existingDocuments;
+        if (session != null) {
+          existingDocuments = await Collection.Find(session, predicate).ToListAsync();
+        }
+        else {
+          existingDocuments = await Collection.Find(predicate).ToListAsync();
         }
 
-        var updatedIds = documents.Select(doc => doc.Id).ToList();
+        // Step 2: Get the existing document IDs
+        var existingIds = existingDocuments.Select(doc => doc.Id).ToHashSet();
+
+        // Step 3: Filter the documents to update only those that exist in the collection
+        var documentsToUpdate = documents.Where(doc => existingIds.Contains(doc.Id)).ToList();
+
+        // Step 4: Update each of the existing documents
+        foreach (var document in documentsToUpdate) {
+          // Handling nullable Id by checking both document.Id and x.Id for null
+          var documentPredicate = (Expression<Func<TDtoDocument, bool>>)(x =>
+              (x.Id == null && document.Id == null) ||
+              (x.Id != null && x.Id.Equals(document.Id)));
+
+          if (session != null) {
+            await Collection.ReplaceOneAsync(session, documentPredicate, document);
+          }
+          else {
+            await Collection.ReplaceOneAsync(documentPredicate, document);
+          }
+        }
+
+        var updatedIds = documentsToUpdate.Select(doc => doc.Id).ToList();
         return Result<List<TDtoKey>?>.Ok(updatedIds);
       }
       catch (Exception ex) {
@@ -137,16 +160,18 @@ namespace MaksIT.MongoDB.Linq.Abstractions {
         Expression<Func<TDtoDocument, bool>> predicate,
         IClientSessionHandle? session) {
       try {
-        foreach (var document in documents) {
-          if (session != null) {
-            await Collection.DeleteOneAsync(session, predicate);
-            await Collection.InsertOneAsync(session, document);
-          }
-          else {
-            await Collection.DeleteOneAsync(predicate);
-            await Collection.InsertOneAsync(document);
-          }
-        }
+        // Deletion
+        if (session != null)
+          await Collection.DeleteManyAsync(session, predicate);
+        else
+          await Collection.DeleteManyAsync(predicate);
+
+        // Creation
+        if (session != null)
+          await Collection.InsertManyAsync(session, documents);
+        else
+          await Collection.InsertManyAsync(documents);
+ 
 
         var upsertedIds = documents.Select(doc => doc.Id).ToList();
         return Result<List<TDtoKey>?>.Ok(upsertedIds);
diff --git a/src/MaksIT.MongoDB.Linq/MaksIT.MongoDB.Linq.csproj b/src/MaksIT.MongoDB.Linq/MaksIT.MongoDB.Linq.csproj
index bef9677..44f0b95 100644
--- a/src/MaksIT.MongoDB.Linq/MaksIT.MongoDB.Linq.csproj
+++ b/src/MaksIT.MongoDB.Linq/MaksIT.MongoDB.Linq.csproj
@@ -8,7 +8,7 @@
 
     <!-- NuGet package metadata -->
     <PackageId>MaksIT.MongoDB.Linq</PackageId>
-    <Version>1.0.4</Version>
+    <Version>1.0.5</Version>
     <Authors>Maksym Sadovnychyy</Authors>
     <Company>MAKS-IT</Company>
     <Product>MaksIT.MongoDB.Linq</Product>