From 38dc42ade8f167796c421d07f7ae6720785c6230 Mon Sep 17 00:00:00 2001
From: sascha <skuehl1972@gmail.com>
Date: Tue, 17 Feb 2026 16:19:14 +0100
Subject: [PATCH] insert_query_builder progress

---
 include/matador/orm/session.hpp               |  46 +++++++
 .../matador/query/insert_query_builder.hpp    | 130 +++++++++++++++++-
 .../matador/query/query_builder_exception.hpp |   1 +
 3 files changed, 173 insertions(+), 4 deletions(-)

diff --git a/include/matador/orm/session.hpp b/include/matador/orm/session.hpp
index 3d48062..f2bc823 100644
--- a/include/matador/orm/session.hpp
+++ b/include/matador/orm/session.hpp
@@ -96,6 +96,52 @@ private:
   const std::unordered_map<std::string, sql::statement> &statements_per_column_;
 };
 
+  /*
+  template<typename Type>
+utils::result<object::object_ptr<Type>, utils::error> session::insert(object::object_ptr<Type> obj) {
+  const auto it = schema_.find(typeid(Type));
+  if (it == schema_.end()) {
+    return utils::failure(make_error(error_code::UnknownType, "Failed to determine requested type."));
+  }
+
+  // Build dependency-ordered insert steps (deps first, root last)
+  query::insert_query_builder iqb(schema_);
+  auto steps = iqb.build(obj);
+  if (!steps.is_ok()) {
+    return utils::failure(make_error(error_code::FailedToBuildQuery, "Failed to build insert dependency queries."));
+  }
+
+  // Execute all steps; for Identity steps read RETURNING and write pk back into the object
+  for (auto &step : *steps) {
+    if (!step.has_returning) {
+      const auto exec_res = step.query.execute(*this);
+      if (!exec_res.is_ok()) {
+        return utils::failure(exec_res.err());
+      }
+      continue;
+    }
+
+    auto stmt_res = step.query.prepare(*this);
+    if (!stmt_res.is_ok()) {
+      return utils::failure(stmt_res.err());
+    }
+
+    // RETURNING produces a result set; fetch the first row (single-row insert)
+    auto rec_res = stmt_res->fetch_one(); // const overload => std::optional<sql::record>
+    if (!rec_res.is_ok()) {
+      return utils::failure(rec_res.err());
+    }
+    if (!rec_res.value().has_value()) {
+      return utils::failure(make_error(error_code::FailedToFindObject, "INSERT ... RETURNING did not return a row."));
+    }
+
+    if (step.apply_returning) {
+      step.apply_returning(*rec_res.value());
+    }
+  }
+
+  return utils::ok(obj);
+}   */
 class session final : public sql::executor {
 public:
   session(session_context &&ctx, const query::schema &scm);
diff --git a/include/matador/query/insert_query_builder.hpp b/include/matador/query/insert_query_builder.hpp
index 48cc194..701e5b6 100644
--- a/include/matador/query/insert_query_builder.hpp
+++ b/include/matador/query/insert_query_builder.hpp
@@ -7,19 +7,56 @@
 #include "matador/query/query_builder_exception.hpp"
 
 namespace matador::query {
+
+struct pk_setter {
+  const std::string &name;
+  std::uint64_t value;
+
+  template<class V>
+  void on_primary_key(const char *id, V &pk, const utils::primary_key_attribute & = utils::default_pk_attributes) {
+    if (id != nullptr && name == id) {
+      pk = static_cast<V>(value);
+    }
+  }
+  static void on_revision(const char * /*id*/, uint64_t & /*rev*/) {}
+  template<typename T>
+  static void on_attribute(const char * /*id*/, T &, const utils::field_attributes & = utils::null_attributes) {}
+  template<class P>
+  static void on_belongs_to(const char * /*id*/, P &, const utils::foreign_attributes & ) {}
+  template<class P>
+  static void on_has_one(const char * /*id*/, P &, const utils::foreign_attributes & ) {}
+  template<class C>
+  static void on_has_many(const char * /*id*/, C &, const char * /*join_column*/, const utils::foreign_attributes & ) {}
+  template<class C>
+  static void on_has_many_to_many(const char * /*id*/, C &, const char * /*join_column*/, const char * /*inverse_join_column*/, const utils::foreign_attributes & ) {}
+  template<class C>
+  static void on_has_many_to_many(const char * /*id*/, C &, const utils::foreign_attributes & ) {}
+};
+
 class insert_query_builder {
+public:
+  struct insert_step {
+    executable_query query;
+    bool has_returning{false};
+    std::function<void(const sql::record &)> apply_returning{};
+  };
+
 public:
   explicit insert_query_builder(const basic_schema &schema);
 
   template<class EntityType>
-  utils::result<std::vector<executable_query>, query_build_error> build(const object::object_ptr<EntityType> &ptr) {
-    const auto it = schema_.find(typeid(EntityType));
+  utils::result<std::vector<insert_step>, query_build_error> build(const object::object_ptr<EntityType> &ptr) {
+    auto it = schema_.find(typeid(EntityType));
     if (it == schema_.end()) {
       return utils::failure(query_build_error::UnknownType);
     }
 
-    executable_query q = query::query::insert().into(it->second.table()).values(*ptr);
-    return utils::ok(std::vector{q});
+    steps_.clear();
+    visited_.clear();
+
+    build_for(ptr);
+
+    return utils::ok(steps_);
   }
 
   template < class V >
@@ -39,8 +76,93 @@ public:
     on_foreign_object(id, obj, attr);
   }
 
+private:
+  template<class EntityType>
+  static std::pair<std::type_index, const void *> make_visit_key(const object::object_ptr<EntityType> &ptr) {
+    return {std::type_index(typeid(EntityType)), static_cast<const void *>(&(*ptr))};
+  }
+
+  struct visit_key_hash {
+    size_t operator()(const std::pair<std::type_index, const void *> &p) const noexcept {
+      // combine hashes (simple + sufficient here)
+      const size_t h1 = p.first.hash_code();
+      const size_t h2 = std::hash<const void *>{}(p.second);
+      return h1 ^ (h2 + 0x9e3779b97f4a7c15ULL + (h1 << 6) + (h1 >> 2));
+    }
+  };
+
+  template<class EntityType>
+  void build_for(const object::object_ptr<EntityType> &ptr) {
+    if (!ptr) {
+      return;
+    }
+
+    const auto key = make_visit_key<EntityType>(ptr);
+    if (visited_.find(key) != visited_.end()) {
+      return;
+    }
+    visited_.insert(key);
+
+    const auto it = schema_.find(typeid(EntityType));
+    if (it == schema_.end()) {
+      throw query_builder_exception(query_build_error::UnknownType);
+    }
+
+    // 1) Traverse relations first => dependencies will be inserted before this object
+    access::process(*this, *ptr);
+
+    // 2) Build INSERT for this object
+    //    For Identity PK strategy: append RETURNING(pk_column)
+    const auto &info = it->second.node().info();
+    if (info.has_primary_key() && info.primary_key_attribute()->generator() == utils::generator_type::Identity) {
+      const std::string pk_name = info.primary_key_attribute()->name();
+      const table_column pk_col(&it->second.table(), pk_name);
+      insert_step step {
+        query::query::insert()
+                               .into(it->second.table())
+                               .values(*ptr)
+                               .returning(pk_col),
+        true,
+        [ptr, pk_name](const sql::record &rec) {
+          // record.at<T>(name) returns optional<T>
+          // We assume integer-like PKs for now (as in your examples).
+          if (auto v = rec.at<std::uint64_t>(pk_name); v.has_value()) {
+            pk_setter setter{pk_name, *v};
+            access::process(setter, *ptr);
+          }
+        }
+      };
+      steps_.push_back(std::move(step));
+      return;
+    }
+
+    insert_step step{
+      query::query::insert().into(it->second.table()).values(*ptr),
+      false,
+      {}
+    };
+    steps_.push_back(std::move(step));
+  }
+
+  template<class Pointer>
+  void on_foreign_object(Pointer &obj, const utils::foreign_attributes & /*attr*/) {
+    if (!obj) {
+      return;
+    }
+
+    // Dependency only matters if the referenced object must be inserted
+    if (obj.is_persistent()) {
+      return;
+    }
+
+    using dep_t = std::remove_reference_t<decltype(*obj)>;
+    build_for<dep_t>(obj);
+  }
 private:
   const basic_schema &schema_;
+
+  std::vector<insert_step> steps_;
+  std::unordered_set<std::pair<std::type_index, const void *>, visit_key_hash> visited_;
 };
 }
 #endif //MATADOR_INSERT_QUERY_BUILDER_HPP
\ No newline at end of file
diff --git a/include/matador/query/query_builder_exception.hpp b/include/matador/query/query_builder_exception.hpp
index 586f19b..499d37f 100644
--- a/include/matador/query/query_builder_exception.hpp
+++ b/include/matador/query/query_builder_exception.hpp
@@ -11,6 +11,7 @@ enum class query_build_error : std::uint8_t {
   Ok = 0,
   UnknownType,
   MissingPrimaryKey,
+  MissingObject,
   UnexpectedError,
   QueryError
 };