//===----------------------------------------------------------------------===//
//                         DuckDB
//
// duckdb/function/function_serialization.hpp
//
//
//===----------------------------------------------------------------------===//

#pragma once

#include "duckdb/main/client_context.hpp"
#include "duckdb/catalog/catalog_entry/table_function_catalog_entry.hpp"
#include "duckdb/common/serializer/serializer.hpp"
#include "duckdb/common/serializer/deserializer.hpp"
#include "duckdb/function/function_binder.hpp"

namespace duckdb {

class FunctionSerializer {
public:
	template <class FUNC>
	static void Serialize(Serializer &serializer, const FUNC &function, optional_ptr<FunctionData> bind_info) {
		D_ASSERT(!function.name.empty());
		serializer.WriteProperty(500, "name", function.name);
		serializer.WriteProperty(501, "arguments", function.arguments);
		serializer.WriteProperty(502, "original_arguments", function.original_arguments);
		// These are optional fields that are written out of numeric order, older
		// databases won't contain the fields, so the defaults will be used, but if
		// the fields are present, they will be used.
		serializer.WritePropertyWithDefault<string>(505, "catalog_name", function.catalog_name, "");
		serializer.WritePropertyWithDefault<string>(506, "schema_name", function.schema_name, "");
		bool has_serialize = function.serialize;
		serializer.WriteProperty(503, "has_serialize", has_serialize);
		if (has_serialize) {
			serializer.WriteObject(504, "function_data",
			                       [&](Serializer &obj) { function.serialize(obj, bind_info, function); });
			D_ASSERT(function.deserialize);
		}
	}

	template <class FUNC, class CATALOG_ENTRY>
	static FUNC DeserializeFunction(ClientContext &context, CatalogType catalog_type, const string &catalog_name,
	                                const string &schema_name, const string &name, const vector<LogicalType> &arguments,
	                                const vector<LogicalType> &original_arguments) {
		EntryLookupInfo lookup_info(catalog_type, name);
		auto &func_catalog =
		    Catalog::GetEntry(context, catalog_type, catalog_name.empty() ? SYSTEM_CATALOG : catalog_name,
		                      schema_name.empty() ? DEFAULT_SCHEMA : schema_name, name);

		if (func_catalog.type != catalog_type) {
			throw InternalException("DeserializeFunction - cant find catalog entry for function %s", name);
		}
		auto &functions = func_catalog.Cast<CATALOG_ENTRY>();
		auto function = functions.functions.GetFunctionByArguments(
		    context, original_arguments.empty() ? arguments : original_arguments);
		return function;
	}

	template <class FUNC, class CATALOG_ENTRY>
	static pair<FUNC, bool> DeserializeBase(Deserializer &deserializer, CatalogType catalog_type,
	                                        optional_ptr<vector<unique_ptr<Expression>>> children = nullptr) {
		auto &context = deserializer.Get<ClientContext &>();
		auto name = deserializer.ReadProperty<string>(500, "name");
		auto arguments = deserializer.ReadProperty<vector<LogicalType>>(501, "arguments");
		auto original_arguments = deserializer.ReadProperty<vector<LogicalType>>(502, "original_arguments");
		auto catalog_name = deserializer.ReadPropertyWithDefault<string>(505, "catalog_name");
		auto schema_name = deserializer.ReadPropertyWithDefault<string>(506, "schema_name");
		if (catalog_name.empty()) {
			catalog_name = SYSTEM_CATALOG;
		}
		if (schema_name.empty()) {
			schema_name = DEFAULT_SCHEMA;
		}

		if (arguments.empty() && original_arguments.empty() && children && !children->empty()) {
			// The function is specified as having no arguments, but somehow expressions were passed anyway
			// Assume this is a "varargs" function and use the types of the expressions as the arguments
			// This can happen when we change a function that used to take varargs, to no longer do so.
			arguments.reserve(children->size());
			for (auto &child : *children) {
				arguments.push_back(child->return_type);
			}
		}

		auto function = DeserializeFunction<FUNC, CATALOG_ENTRY>(context, catalog_type, catalog_name, schema_name, name,
		                                                         arguments, original_arguments);
		auto has_serialize = deserializer.ReadProperty<bool>(503, "has_serialize");
		if (has_serialize) {
			function.arguments = std::move(arguments);
			function.original_arguments = std::move(original_arguments);
		}
		return make_pair(std::move(function), has_serialize);
	}

	template <class FUNC>
	static unique_ptr<FunctionData> FunctionDeserialize(Deserializer &deserializer, FUNC &function) {
		if (!function.deserialize) {
			throw SerializationException("Function requires deserialization but no deserialization function for %s",
			                             function.name);
		}
		unique_ptr<FunctionData> result;
		deserializer.ReadObject(504, "function_data",
		                        [&](Deserializer &obj) { result = function.deserialize(obj, function); });
		return result;
	}

	static bool TypeRequiresAssignment(const LogicalType &type) {
		switch (type.id()) {
		case LogicalTypeId::SQLNULL:
		case LogicalTypeId::ANY:
		case LogicalTypeId::INVALID:
			return true;
		case LogicalTypeId::DECIMAL:
		case LogicalTypeId::UNION:
		case LogicalTypeId::VARIANT:
		case LogicalTypeId::MAP:
			if (!type.AuxInfo()) {
				return true;
			}
			return false;
		case LogicalTypeId::LIST:
			if (!type.AuxInfo()) {
				return true;
			}
			return TypeRequiresAssignment(ListType::GetChildType(type));
		case LogicalTypeId::ARRAY:
			if (!type.AuxInfo()) {
				return true;
			}
			return TypeRequiresAssignment(ArrayType::GetChildType(type));
		case LogicalTypeId::STRUCT:
			if (!type.AuxInfo()) {
				return true;
			}
			if (StructType::GetChildCount(type) == 0) {
				return true;
			}
			return false;
		default:
			return false;
		}
	}

	template <class FUNC, class CATALOG_ENTRY>
	static pair<FUNC, unique_ptr<FunctionData>> Deserialize(Deserializer &deserializer, CatalogType catalog_type,
	                                                        vector<unique_ptr<Expression>> &children,
	                                                        LogicalType return_type) { // NOLINT: clang-tidy bug
		auto &context = deserializer.Get<ClientContext &>();
		auto entry = DeserializeBase<FUNC, CATALOG_ENTRY>(deserializer, catalog_type, children);
		auto &function = entry.first;
		auto has_serialize = entry.second;

		unique_ptr<FunctionData> bind_data;
		if (has_serialize) {
			deserializer.Set<const LogicalType &>(return_type);
			bind_data = FunctionDeserialize<FUNC>(deserializer, function);
			deserializer.Unset<LogicalType>();
		} else {

			FunctionBinder binder(context);

			// Resolve templates
			binder.ResolveTemplateTypes(function, children);

			if (function.bind) {
				try {
					bind_data = function.bind(context, function, children);
				} catch (std::exception &ex) {
					ErrorData error(ex);
					throw SerializationException("Error during bind of function in deserialization: %s",
					                             error.RawMessage());
				}
			}

			// Verify that all templates are bound to concrete types.
			binder.CheckTemplateTypesResolved(function);

			binder.CastToFunctionArguments(function, children);
		}

		if (TypeRequiresAssignment(function.return_type)) {
			function.return_type = std::move(return_type);
		}
		return make_pair(std::move(function), std::move(bind_data));
	}
};

} // namespace duckdb
