progress on session_insert_builder

include/matador/orm/session_insert_builder.hpp

@@ -1,9 +1,108 @@
 #ifndef SESSION_INSERT_BUILDER_HPP
 #define SESSION_INSERT_BUILDER_HPP
 
+#include "matador/query/condition.hpp"
+#include "matador/query/query_intermediates.hpp"
+
+#include "matador/object/schema.hpp"
+
 namespace matador::orm {
 
+struct entity_insert_data {
+    sql::table table;
+    std::vector<std::string> columns;
+    std::vector<utils::database_type> values;
+};
+
+enum class insert_build_error : std::uint8_t {
+    Ok = 0,
+    UnknownType,
+    MissingPrimaryKey,
+    UnexpectedError
+};
+
+class insert_builder_exception final : public std::exception
+{
+public:
+    explicit insert_builder_exception(const insert_build_error error) : error_(error) {}
+
+    [[nodiscard]] insert_build_error error() const { return error_; }
+
+private:
+    const insert_build_error error_;
+};
+
 class session_insert_builder final {
+public:
+    explicit session_insert_builder(const object::schema &scm)
+    : schema_(scm) {}
+
+    template<class EntityType>
+    utils::result<std::vector<entity_insert_data>, insert_build_error> build(const EntityType &obj) {
+        auto info = schema_.info<EntityType>();
+        if (!info) {
+            return utils::failure(insert_build_error::UnknownType);
+        }
+        table_info_stack_.push({info.value()});
+        entity_insert_data_ = {{sql::table{info.value().get().name()}}};
+        // processed_tables_.insert({info->get().name(), entity_insert_data_.root_table});
+        try {
+            access::process(*this, obj);
+
+            return {utils::ok(std::move(entity_insert_data_))};
+        } catch (const insert_builder_exception &ex) {
+            return {utils::failure(ex.error())};
+        } catch (...) {
+            return {utils::failure(insert_build_error::UnexpectedError)};
+        }
+    }
+
+    template < class V >
+    void on_primary_key(const char *id, V &x, std::enable_if_t<std::is_integral_v<V> && !std::is_same_v<bool, V>>* = nullptr)
+    {
+        push(id, x);
+    }
+
+    void on_primary_key(const char *id, std::string &, size_t);
+    void on_revision(const char *id, unsigned long long &/*rev*/);
+
+      template<typename Type>
+  void on_attribute(const char *id, Type &, const utils::field_attributes &/*attr*/ = utils::null_attributes) {
+  }
+
+  template<class Pointer>
+  void on_belongs_to(const char *id, Pointer &obj, const utils::foreign_attributes &attr) {
+  }
+
+  template<class Pointer>
+  void on_has_one(const char *id, Pointer &obj, const utils::foreign_attributes &attr) {
+  }
+
+  template<class ContainerType>
+  void on_has_many(const char * /*id*/, ContainerType &, const char *join_column, const utils::foreign_attributes &attr) {
+  }
+
+  template<class ContainerType>
+  void on_has_many_to_many(const char *id, ContainerType &/*cont*/, const char *join_column, const char *inverse_join_column, const utils::foreign_attributes &attr) {
+  }
+
+  template<class ContainerType>
+  void on_has_many_to_many(const char *id, ContainerType &/*cont*/, const utils::foreign_attributes &attr) {
+  }
+
+private:
+  [[nodiscard]] bool is_root_entity() const;
+  void push(const std::string &column_name, const utils::database_type &value);
+
+private:
+  struct table_info {
+    std::reference_wrapper<const object::basic_object_info> info;
+  };
+
+  std::stack<table_info> table_info_stack_;
+  std::unordered_map<std::string, std::shared_ptr<sql::table>> processed_tables_;
+  const object::schema &schema_;
+  std::vector<entity_insert_data> entity_insert_data_;
 };
 
 }

include/matador/utils/uuid.hpp

@@ -0,0 +1,50 @@
+#ifndef MATADOR_UUID_HPP
+#define MATADOR_UUID_HPP
+
+#include <array>
+#include <string>
+
+namespace matador::utils {
+
+class uuid {
+public:
+    using uuid_array = std::array<uint32_t, 4>;
+
+    // Default constructor initializes to zero
+    uuid() = default;
+
+    // Static UUID v4 generator
+    static uuid generate();
+
+    // Returns UUID as a string
+    [[nodiscard]] std::string str() const;
+
+    // Access to internal data
+    [[nodiscard]] const uuid_array& data() const;
+
+    // Reset UUID to zero
+    void clear() { _data.fill(0); }
+
+    // Comparisons
+    friend bool operator==(const uuid& lhs, const uuid& rhs);
+    friend bool operator!=(const uuid& lhs, const uuid& rhs);
+    friend bool operator<(const uuid& lhs, const uuid& rhs);
+
+private:
+    uuid_array _data{0, 0, 0, 0};
+};
+}
+
+// Hash specialization to allow use in unordered containers
+template <>
+struct std::hash<matador::utils::uuid> {
+    std::size_t operator()(const matador::utils::uuid& u) const noexcept {
+        std::size_t h = 0;
+        for (uint32_t val : u.data()) {
+            h ^= std::hash<uint32_t>{}(val) + 0x9e3779b9 + (h << 6) + (h >> 2);
+        }
+        return h;
+    }
+};
+
+#endif //MATADOR_UUID_HPP