Put database in class and use throw exceptions.

src/arg_parse.hpp

@@ -36,7 +36,7 @@ static const std::map<enum cmd_id, std::vector<std::string>> commands = {
 	{ CMD_ADD, {"add", "new"} },
 	{ CMD_LIST, {"list", "ls"} },
 	{ CMD_DEL, {"del", "rm"} },
-	{ CMD_INFO, { "info" } },
+	{ CMD_INFO, {"info", "i"} },
 	{ CMD_HELP, {"help", "-h", "--help"} },
 	{ CMD_VERSION, {"version", "-v", "--version"} },
 };

src/cmd.cpp

@@ -19,13 +19,14 @@
 #include "db.hpp"
 #include "util.hpp"
 
-#include <iostream>
 #include <cstdlib>
+#include <iostream>
 #include <string>
-#include <vector>
 #include <unistd.h>
+#include <vector>
 
-int command_add(void) {
+int cmd_add(void) {
+	db db;
 	std::string name, description, ingredients, tags;
 	int recipe_id, ingredient_id, tag_id;
 
@@ -41,36 +42,34 @@ int command_add(void) {
 	std::cout << "Tags (comma separated): ";
 	getline(std::cin, tags);
 
-	if(not db_open()) {
+	db.open();
-		std::cerr << "Failed to open database. Cannot add new entry." << std::endl;
-		return EXIT_FAILURE;
-	}
 
-	if((recipe_id = db_get_recipe_id(name)) <= 0)
+	if((recipe_id = db.get_recipe_id(name)) <= 0)
-		recipe_id = db_add_recipe(name, description);
+		recipe_id = db.add_recipe(name, description);
 
 	for(auto &ingredient : split(ingredients, ",")) {
 		trim(ingredient);
 
-		if((ingredient_id = db_get_ingredient_id(ingredient)) <= 0)
+		if((ingredient_id = db.get_ingredient_id(ingredient)) <= 0)
-			ingredient_id = db_add_ingredient(ingredient);
+			ingredient_id = db.add_ingredient(ingredient);
-		db_conn_recipe_ingredient(recipe_id, ingredient_id);
+		db.conn_recipe_ingredient(recipe_id, ingredient_id);
 	}
 
 	for(auto &tag : split(tags, ",")) {
 		trim(tag);
 
-		if((tag_id = db_get_tag_id(tag)) <= 0)
+		if((tag_id = db.get_tag_id(tag)) <= 0)
-			tag_id = db_add_tag(tag);
+			tag_id = db.add_tag(tag);
-		db_conn_recipe_tag(recipe_id, tag_id);
+		db.conn_recipe_tag(recipe_id, tag_id);
 	}
 
-	db_close();
+	db.close();
 
 	return EXIT_SUCCESS;
 }
 
-int command_list(int argc, char *argv[]) {
+int cmd_list(int argc, char *argv[]) {
+	db db;
 	std::vector<std::string> ingredients, tags;
 	int opt;
 
@@ -93,21 +92,18 @@ int command_list(int argc, char *argv[]) {
 		}
 	}
 
-	if(not db_open()) {
+	db.open();
-		std::cerr << "Failed to open database. Cannot add new entry." << std::endl;
-		return EXIT_FAILURE;
-	}
 
-	for(const auto &recipe : db_get_recipes(ingredients, tags))
+	for(const auto &recipe : db.get_recipes(ingredients, tags))
 		std::cout << recipe.id << "  |  " << recipe.name << "  |  " << recipe.description << std::endl;
 
-	db_close();
+	db.close();
 
 	return EXIT_SUCCESS;
 }
 
-int command_delete(int argc, char *argv[]) {
+int cmd_delete(int argc, char *argv[]) {
-	int ret = EXIT_SUCCESS;
+	db db;
 	std::vector<int> recipe_ids;
 
 	if(argc < 1) {
@@ -115,15 +111,12 @@ int command_delete(int argc, char *argv[]) {
 		return EXIT_FAILURE;
 	}
 
-	if(not db_open()) {
+	db.open();
-		std::cerr << "Failed to open database. Cannot add new entry." << std::endl;
-		return EXIT_FAILURE;
-	}
 
 	for(int i = 0; i < argc; ++i) {
 		const int id = std::stoi(argv[i]);
 
-		if(not db_recipe_exists(id)) {
+		if(not db.recipe_exists(id)) {
 			std::cerr << "No recipe exists with ID " << id << "." << std::endl;
 			return EXIT_FAILURE;
 		} else {
@@ -131,33 +124,30 @@ int command_delete(int argc, char *argv[]) {
 		}
 	}
 
-	ret = (db_del_recipes(recipe_ids)) ? EXIT_SUCCESS : EXIT_FAILURE;
+	db.del_recipes(recipe_ids);
+	db.close();
 
-	db_close();
+	return EXIT_SUCCESS;
-
-	return ret;
 }
 
-int command_info(const int id) {
+int cmd_info(const int id) {
+	db db;
 	struct recipe recipe;
 	std::vector<std::string> ingredients, tags;
 	int ret = EXIT_SUCCESS;
 
-	if(not db_open()) {
+	db.open();
-		std::cerr << "Failed to open database. Cannot add new entry." << std::endl;
-		return EXIT_FAILURE;
-	}
 
-	if(not db_recipe_exists(id)) {
+	if(not db.recipe_exists(id)) {
 		std::cerr << "No recipe with ID '" << id << "'";
 		return EXIT_FAILURE;
 	}
 
-	recipe = db_get_recipe(id);
+	recipe = db.get_recipe(id);
-	ingredients = db_get_recipe_ingredients(id);
+	ingredients = db.get_recipe_ingredients(id);
-	tags = db_get_recipe_tags(id);
+	tags = db.get_recipe_tags(id);
 
-	db_close();
+	db.close();
 
 	std::cout << "Name: " << recipe.name << "\n"
 		<< "Description: " << recipe.description << "\n"

src/cmd.hpp

@@ -17,7 +17,7 @@
  */
 #pragma once
 
-int command_add(void);
+int cmd_add(void);
-int command_list(int argc, char *argv[]);
+int cmd_list(int argc, char *argv[]);
-int command_delete(int argc, char *argv[]);
+int cmd_delete(int argc, char *argv[]);
-int command_info(const int id);
+int cmd_info(const int id);

src/db.cpp

@@ -17,28 +17,22 @@
  */
 #include "db.hpp"
 
-#include <sqlite3.h>
 #include <cstdlib>
-#include <iostream>
 #include <filesystem>
 #include <format>
-#include <string>
+#include <iostream>
-#include <vector>
+#include <sqlite3.h>
+#include <stdexcept>
 
 #define DB_VERSION 1
-static sqlite3 *db = nullptr;
 
-int db_open(void) {
+void db::open(void) {
 	std::string xdg_data_home;
 	std::string db_path;
 	bool new_db = false;
-	int rc;
 
-	if((xdg_data_home = std::getenv("XDG_DATA_HOME")).empty()) {
+	if((xdg_data_home = std::getenv("XDG_DATA_HOME")).empty())
-		std::cerr << "Cannot find environment variable XDG_DATA_HOME. Please define it before continuing. E.g.:\n"
+		throw std::runtime_error("Cannot find environment variable XDG_DATA_HOME. Please define it before continuing.");
-			"export XDG_DATA_HOME=\"$HOME/.local/share\"" << std::endl;
-		return 0;
-	}
 
 	db_path = xdg_data_home + "/menu-helper";
 
@@ -52,26 +46,26 @@ int db_open(void) {
 		new_db = true;
 	}
 
-	rc = sqlite3_open(db_path.c_str(), &db);
+	if(sqlite3_open(db_path.c_str(), &sqlite_db) not_eq SQLITE_OK)
+		throw std::runtime_error("Failed to open database file " + db_path);
 
-	if(rc == SQLITE_OK and new_db) {
+	if(new_db) {
-		sqlite3_exec(db, "CREATE TABLE db_version(version INTEGER UNIQUE NOT nullptr);", nullptr, nullptr, nullptr);
+		sqlite3_exec(sqlite_db, "CREATE TABLE db_version(version INTEGER UNIQUE NOT nullptr);", nullptr, nullptr, nullptr);
-		sqlite3_exec(db, std::format("INSERT INTO db_version VALUES({});", DB_VERSION).c_str(), nullptr, nullptr, nullptr);
+		sqlite3_exec(sqlite_db, std::format("INSERT INTO db_version VALUES({});", DB_VERSION).c_str(), nullptr, nullptr, nullptr);
-		sqlite3_exec(db, "CREATE TABLE tags(id INTEGER PRIMARY KEY AUTOINCREMENT, name STRING UNIQUE);", nullptr, nullptr, nullptr);
+		sqlite3_exec(sqlite_db, "CREATE TABLE tags(id INTEGER PRIMARY KEY AUTOINCREMENT, name STRING UNIQUE);", nullptr, nullptr, nullptr);
-		sqlite3_exec(db, "CREATE TABLE ingredients(id INTEGER PRIMARY KEY AUTOINCREMENT, name STRING UNIQUE);", nullptr, nullptr, nullptr);
+		sqlite3_exec(sqlite_db, "CREATE TABLE ingredients(id INTEGER PRIMARY KEY AUTOINCREMENT, name STRING UNIQUE);", nullptr, nullptr, nullptr);
-		sqlite3_exec(db, "CREATE TABLE recipes(id INTEGER PRIMARY KEY AUTOINCREMENT, name STRING UNIQUE, description STRING);", nullptr, nullptr, nullptr);
+		sqlite3_exec(sqlite_db, "CREATE TABLE recipes(id INTEGER PRIMARY KEY AUTOINCREMENT, name STRING UNIQUE, description STRING);", nullptr, nullptr, nullptr);
-		sqlite3_exec(db, "CREATE TABLE recipe_tag(recipe_id INTEGER REFERENCES recipes(id) ON DELETE CASCADE, tag_id INTEGER REFERENCES tags(id) ON DELETE CASCADE);", nullptr, nullptr, nullptr);
+		sqlite3_exec(sqlite_db, "CREATE TABLE recipe_tag(recipe_id INTEGER REFERENCES recipes(id) ON DELETE CASCADE, tag_id INTEGER REFERENCES tags(id) ON DELETE CASCADE);", nullptr, nullptr, nullptr);
-		sqlite3_exec(db, "CREATE TABLE recipe_ingredient(recipe_id INTEGER REFERENCES recipes(id) ON DELETE CASCADE, ingredient_id INTEGER REFERENCES ingredients(id) ON DELETE CASCADE);", nullptr, nullptr, nullptr);
+		sqlite3_exec(sqlite_db, "CREATE TABLE recipe_ingredient(recipe_id INTEGER REFERENCES recipes(id) ON DELETE CASCADE, ingredient_id INTEGER REFERENCES ingredients(id) ON DELETE CASCADE);", nullptr, nullptr, nullptr);
+	}
 }
 
-	return rc == SQLITE_OK;
+void db::close(void) {
-}
+	if(not sqlite_db)
-
-void db_close(void) {
-	if(not db)
 		return;
 
-	sqlite3_close(db);
+	sqlite3_close(sqlite_db);
+	sqlite_db = nullptr;
 }
 
 int query_id_cb(void *recipe_id_var, int col_num, char **col_data, char **col_name) {
@@ -89,43 +83,47 @@ int query_id_cb(void *recipe_id_var, int col_num, char **col_data, char **col_na
 	return ret;
 }
 
-int table_get_id_by_name(const std::string &table, const std::string &name) {
+int db::table_get_id_by_name(const std::string &table, const std::string &name) {
 	int id = 0;
 
-	if(sqlite3_exec(db, std::format("SELECT id FROM {} WHERE lower(name)=lower('{}');", table, name).c_str(),
+	if(not sqlite_db)
-					query_id_cb, &id, nullptr) not_eq SQLITE_OK)
+		throw std::runtime_error(std::format("{}: Database not open! Please contact a developer.", __PRETTY_FUNCTION__));
-		return -2;
+
+	if(sqlite3_exec(sqlite_db, std::format("SELECT id FROM {} WHERE lower(name)=lower('{}');", table, name).c_str(),
+					query_id_cb, &id, nullptr) not_eq SQLITE_OK) {
+		throw std::runtime_error(std::format("Failed to get ID of '{}' from table '{}'.", name, table));
+	}
 
 	return id;
 }
 
-int db_add_recipe(const std::string &name, const std::string &description) {
+int db::add_recipe(const std::string &name, const std::string &description) {
-	if(not db)
+	if(not sqlite_db)
-		return -1;
+		throw std::runtime_error(std::format("{}: Database not open! Please contact a developer.", __PRETTY_FUNCTION__));
 
-	if(sqlite3_exec(db, std::format("INSERT INTO recipes(name,description) VALUES('{}','{}');", name, description).c_str(),
+	if(sqlite3_exec(sqlite_db, std::format("INSERT INTO recipes(name,description) VALUES('{}','{}');", name, description).c_str(),
-					nullptr, nullptr, nullptr) not_eq SQLITE_OK)
+					nullptr, nullptr, nullptr) not_eq SQLITE_OK) {
-		return -2;
+		throw std::runtime_error("Failed to insert new recipe into database.");
-
-	return db_get_recipe_id(name);
 	}
 
-bool db_del_recipe(const int id) {
+	return get_recipe_id(name);
-	if(not db)
-		return false;
-
-	if(sqlite3_exec(db, std::format("DELETE FROM recipes WHERE id={}", id).c_str(),
-					nullptr, nullptr, nullptr) not_eq SQLITE_OK)
-		return false;
-
-	return true;
 }
 
-bool db_del_recipes(const std::vector<int> &ids) {
+void db::del_recipe(const int id) {
+	if(not sqlite_db)
+		throw std::runtime_error(std::format("{}: Database not open! Please contact a developer.", __PRETTY_FUNCTION__));
+
+	if(sqlite3_exec(sqlite_db, std::format("DELETE FROM recipes WHERE id={}", id).c_str(),
+					nullptr, nullptr, nullptr) not_eq SQLITE_OK) {
+		throw std::runtime_error(std::format("Failed to delete recipe with ID {} from database.", id));
+	}
+}
+
+void db::del_recipes(const std::vector<int> &ids) {
 	std::string stmt = "DELETE FROM recipes WHERE id IN (";
 
-	if(not db)
+	if(not sqlite_db)
-		return false;
+		throw std::runtime_error(std::format("{}: Database not open! Please contact a developer.", __PRETTY_FUNCTION__));
 
 	bool first = true;
 	for(auto id : ids) {
@@ -139,53 +137,54 @@ bool db_del_recipes(const std::vector<int> &ids) {
 
 	stmt += ");";
 
-	if(sqlite3_exec(db, stmt.c_str(), nullptr, nullptr, nullptr) not_eq SQLITE_OK)
+	if(sqlite3_exec(sqlite_db, stmt.c_str(), nullptr, nullptr, nullptr) not_eq SQLITE_OK)
-		return false;
+		throw std::runtime_error("Failed to delete recipes from database.");
-
-	return true;
 }
 
-bool db_recipe_exists(const int id) {
+bool db::recipe_exists(const int id) {
 	bool exists = false;
 
-	if(not db)
+	if(not sqlite_db)
-		return false;
+		throw std::runtime_error(std::format("{}: Database not open! Please contact a developer.", __PRETTY_FUNCTION__));
 
-	sqlite3_exec(db, std::format("SELECT id FROM recipes WHERE id={}", id).c_str(),
+	if(sqlite3_exec(sqlite_db, std::format("SELECT id FROM recipes WHERE id={}", id).c_str(),
 					[](void *found,int,char**,char**) {
 					*static_cast<bool*>(found) = true;
 					return 0;
-				 }, &exists, nullptr);
+					}, &exists, nullptr) not_eq SQLITE_OK) {
+		throw std::runtime_error("Failed to select from database.");
+	}
 
 	return exists;
 }
 
-int db_get_recipe_id(const std::string &name) {
+struct recipe db::get_recipe(const int id) {
-	if(not db)
-		return -1;
-
-	return table_get_id_by_name("recipes", name);
-}
-
-struct recipe db_get_recipe(const int id) {
 	struct recipe recipe;
 
-	sqlite3_exec(db, std::format("SELECT * FROM recipes WHERE id={};", id).c_str(),
+	if(not sqlite_db)
+		throw std::runtime_error(std::format("{}: Database not open! Please contact a developer.", __PRETTY_FUNCTION__));
+
+	if(sqlite3_exec(sqlite_db, std::format("SELECT * FROM recipes WHERE id={};", id).c_str(),
 					[](void *recipe, int, char **col_data, char**) {
 					*static_cast<struct recipe*>(recipe) = { std::atoi(col_data[0]), col_data[1], col_data[2] };
 					return 0;
-				 }, &recipe, nullptr);
+					}, &recipe, nullptr) not_eq SQLITE_OK) {
+		throw std::runtime_error("Failed to select from database.");
+	}
 
 	return recipe;
 }
 
-std::vector<struct recipe> db_get_recipes(const std::vector<std::string> &ingredients,
+std::vector<struct recipe> db::get_recipes(const std::vector<std::string> &ingredients,
 										   const std::vector<std::string> &tags)
 {
 	std::vector<struct recipe> recipes;
 	std::string stmt = "SELECT id,name,description FROM recipes";
 	std::string filters;
 
+	if(not sqlite_db)
+		throw std::runtime_error(std::format("{}: Database not open! Please contact a developer.", __PRETTY_FUNCTION__));
+
 	if(not ingredients.empty() or not tags.empty())
 		filters += " WHERE";
 
@@ -201,14 +200,10 @@ std::vector<struct recipe> db_get_recipes(const std::vector<std::string> &ingred
 
 			filters += " id IN (SELECT recipe_id FROM recipe_ingredient WHERE ingredient_id=";
 
-			// TODO: use throw?
+			if((id = get_ingredient_id(i)) <= 0)
-			if((id = db_get_ingredient_id(i)) < 0) {
+				throw std::runtime_error(std::format("Failed to find ingredient '{}'", i));
-				std::cerr << "Failed to find ingredient '" << i << "'" << std::endl;
-				return std::vector<struct recipe>();
-			} else {
-				filters += std::to_string(id);
-			}
 
+			filters += std::to_string(id);
 			filters += ")";
 		}
 	}
@@ -228,111 +223,106 @@ std::vector<struct recipe> db_get_recipes(const std::vector<std::string> &ingred
 
 			filters += " id IN (SELECT recipe_id FROM recipe_tag WHERE tag_id=";
 
-			// TODO: use throw?
+			if((id = get_tag_id(i)) <= 0)
-			if((id = db_get_tag_id(i)) < 0) {
+				throw std::runtime_error("Failed to find tag '{}'");
-				std::cerr << "Failed to find tag '" << i << "'" << std::endl;
-				return std::vector<struct recipe>();
-			} else {
-				filters += std::to_string(id);
-			}
 
+			filters += std::to_string(id);
 			filters += ")";
 		}
 	}
 
 	stmt += filters + ";";
 
-	sqlite3_exec(db, stmt.c_str(),
+	if(sqlite3_exec(sqlite_db, stmt.c_str(),
 					[](void *recipe_list, int, char **col_data, char**) {
-				 	auto recipe_vec = static_cast<std::vector<struct recipe>*>(recipe_list);
+					static_cast<std::vector<struct recipe>*>(recipe_list)->push_back({
-					recipe_vec->push_back({
 																					 std::atoi(col_data[0]),
 																					 col_data[1],
 																					 col_data[2] });
 					return 0;
-				 }, &recipes, nullptr);
+					}, &recipes, nullptr) not_eq SQLITE_OK) {
+		throw std::runtime_error("Failed to select recipes.");
+	}
 
 	return recipes;
 }
 
-int db_add_ingredient(const std::string &name) {
+int db::add_ingredient(const std::string &name) {
-	if(not db)
+	if(not sqlite_db)
-		return -1;
+		throw std::runtime_error(std::format("{}: Database not open! Please contact a developer.", __PRETTY_FUNCTION__));
 
-	if(sqlite3_exec(db, std::format("INSERT INTO ingredients(name) VALUES(lower('{}'));", name).c_str(),
+	if(sqlite3_exec(sqlite_db, std::format("INSERT INTO ingredients(name) VALUES(lower('{}'));", name).c_str(),
-					nullptr, nullptr, nullptr) not_eq SQLITE_OK)
+					nullptr, nullptr, nullptr) not_eq SQLITE_OK) {
-		return -2;
+		throw std::runtime_error(std::format("Failed to instert ingredient '{}'.", name));
-
-	return db_get_ingredient_id(name);
 	}
 
-std::vector<std::string> db_get_recipe_ingredients(const int id) {
+	return get_ingredient_id(name);
+}
+
+std::vector<std::string> db::get_recipe_ingredients(const int id) {
 	std::vector<std::string> ingredients;
 
-	sqlite3_exec(db, std::format("SELECT name FROM ingredients WHERE id IN (SELECT ingredient_id FROM recipe_ingredient WHERE recipe_id={});", id).c_str(),
+	if(not sqlite_db)
+		throw std::runtime_error(std::format("{}: Database not open! Please contact a developer.", __PRETTY_FUNCTION__));
+
+	if(sqlite3_exec(sqlite_db, std::format("SELECT name FROM ingredients WHERE id IN (SELECT ingredient_id FROM recipe_ingredient WHERE recipe_id={});", id).c_str(),
 					[](void *ingredients, int, char **col_data, char**) {
 					static_cast<std::vector<std::string>*>(ingredients)->push_back(col_data[0]);
 					return 0;
-				 }, &ingredients, nullptr);
+					}, &ingredients, nullptr) not_eq SQLITE_OK) {
+		throw std::runtime_error(std::format("Failed to select ingredients from recipe with ID {}", id));
+	}
 
 	return ingredients;
 }
 
-int db_get_ingredient_id(const std::string &name) {
+int db::add_tag(const std::string &name) {
-	if(not db)
+	if(not sqlite_db)
-		return -1;
+		throw std::runtime_error(std::format("{}: Database not open! Please contact a developer.", __PRETTY_FUNCTION__));
 
-	return table_get_id_by_name("ingredients", name);
+	if(sqlite3_exec(sqlite_db, std::format("INSERT INTO tags(name) VALUES('{}');", name).c_str(),
+					nullptr, nullptr, nullptr) not_eq SQLITE_OK) {
+		throw std::runtime_error(std::format("Failed to insert tag '{}'", name));
 	}
 
-int db_add_tag(const std::string &name) {
+	return get_tag_id(name);
-	if(not db)
-		return -1;
-
-	if(sqlite3_exec(db, std::format("INSERT INTO tags(name) VALUES('{}');", name).c_str(),
-					nullptr, nullptr, nullptr) not_eq SQLITE_OK)
-		return -2;
-
-	return db_get_tag_id(name);
 }
 
-std::vector<std::string> db_get_recipe_tags(const int id) {
+std::vector<std::string> db::get_recipe_tags(const int id) {
 	std::vector<std::string> tags;
 
-	sqlite3_exec(db, std::format("SELECT name FROM tags WHERE id IN (SELECT tag_id FROM recipe_tag WHERE recipe_id={});", id).c_str(),
+	if(not sqlite_db)
+		throw std::runtime_error(std::format("{}: Database not open! Please contact a developer.", __PRETTY_FUNCTION__));
+
+	if(sqlite3_exec(sqlite_db, std::format("SELECT name FROM tags WHERE id IN (SELECT tag_id FROM recipe_tag WHERE recipe_id={});", id).c_str(),
 					[](void *tags, int, char **col_data, char**) {
 					static_cast<std::vector<std::string>*>(tags)->push_back(col_data[0]);
 					return 0;
-				 }, &tags, nullptr);
+					}, &tags, nullptr) not_eq SQLITE_OK) {
+		throw std::runtime_error(std::format("Failed to select tags for recipe with ID {}", id));
+	}
 
 	return tags;
 }
 
-int db_get_tag_id(const std::string &name) {
+void db::conn_recipe_ingredient(int recipe_id, int ingredient_id) {
-	if(not db)
+	if(not sqlite_db)
-		return -1;
+		throw std::runtime_error(std::format("{}: Database not open! Please contact a developer.", __PRETTY_FUNCTION__));
 
-	return table_get_id_by_name("tags", name);
+	if(sqlite3_exec(sqlite_db, std::format("INSERT INTO recipe_ingredient(recipe_id, ingredient_id) VALUES({},{});", recipe_id, ingredient_id).c_str(),
+					nullptr, nullptr, nullptr) not_eq SQLITE_OK) {
+		throw std::runtime_error(std::format("Failed to connect recipe with ID {} to ingredient with ID {}",
+												  recipe_id, ingredient_id));
+	}
 }
 
-int db_conn_recipe_ingredient(int recipe_id, int ingredient_id) {
+void db::conn_recipe_tag(int recipe_id, int tag_id) {
-	if(not db)
+	if(not sqlite_db)
-		return -1;
+		throw std::runtime_error(std::format("{}: Database not open! Please contact a developer.", __PRETTY_FUNCTION__));
 
-	if(sqlite3_exec(db, std::format("INSERT INTO recipe_ingredient(recipe_id, ingredient_id) VALUES({},{});", recipe_id, ingredient_id).c_str(),
+	if(sqlite3_exec(sqlite_db, std::format("INSERT INTO recipe_tag(recipe_id, tag_id) VALUES({},{});", recipe_id, tag_id).c_str(),
-					nullptr, nullptr, nullptr) not_eq SQLITE_OK)
+					nullptr, nullptr, nullptr) not_eq SQLITE_OK) {
-		return -2;
+		throw std::runtime_error(std::format("Failed to connect recipe with ID {} to tag with ID {}",
-
+												  recipe_id, tag_id));
-	return 1;
 	}
-
-int db_conn_recipe_tag(int recipe_id, int tag_id) {
-	if(not db)
-		return -1;
-
-	if(sqlite3_exec(db, std::format("INSERT INTO recipe_tag(recipe_id, tag_id) VALUES({},{});", recipe_id, tag_id).c_str(),
-					nullptr, nullptr, nullptr) not_eq SQLITE_OK)
-		return -2;
-
-	return 1;
 }

src/db.hpp

@@ -17,6 +17,7 @@
  */
 #pragma once
 
+#include <sqlite3.h>
 #include <string>
 #include <vector>
 
@@ -26,8 +27,18 @@ struct recipe {
 	std::string description;
 };
 
-int db_open(void);
+class db {
-void db_close(void);
+private:
+	sqlite3 *sqlite_db;
+	int table_get_id_by_name(const std::string &table, const std::string &name);
+
+public:
+	db() : sqlite_db(nullptr) {}
+	~db() {
+		sqlite3_close(sqlite_db);
+	}
+	void open(void);
+	void close(void);
 
 	/**
 	 * @brief Add a new recipe to the database.
@@ -35,18 +46,20 @@ void db_close(void);
 	 * @param name Name of the new recipe.
 	 * @param description Short description.
 	 *
- * @return ID of newly created recipe, -1 if DB isn't open, -2 on other failure.
+	 * @return ID of newly created recipe.
 	 */
-int db_add_recipe(const std::string &name, const std::string &description);
+	int add_recipe(const std::string &name, const std::string &description);
-bool db_del_recipe(const int id);
+	void del_recipe(const int id);
-bool db_del_recipes(const std::vector<int> &ids);
+	void del_recipes(const std::vector<int> &ids);
-int db_get_recipe_id(const std::string &name);
+	inline int get_recipe_id(const std::string &name) {
-bool db_recipe_exists(const int id);
+		return table_get_id_by_name("recipes", name);
-static inline bool db_recipe_exists(const std::string &name) {
-	return (db_get_recipe_id(name) > 0);
 	}
-struct recipe db_get_recipe(const int id);
+	inline bool db_recipe_exists(const std::string &name) {
-std::vector<struct recipe> db_get_recipes(const std::vector<std::string> &ingredients,
+		return (get_recipe_id(name) > 0);
+	}
+	bool recipe_exists(const int id);
+	struct recipe get_recipe(const int id);
+	std::vector<struct recipe> get_recipes(const std::vector<std::string> &ingredients,
 										   const std::vector<std::string> &tags);
 
 	/**
@@ -54,13 +67,15 @@ std::vector<struct recipe> db_get_recipes(const std::vector<std::string> &ingred
 	 *
 	 * @param name Name of the new ingredient.
 	 *
- * @return ID of newly created ingredient, -1 if DB isn't open, -2 on other failure.
+	 * @return ID of newly created ingredient.
 	 */
-int db_add_ingredient(const std::string &name);
+	int add_ingredient(const std::string &name);
-std::vector<std::string> db_get_recipe_ingredients(const int id);
+	std::vector<std::string> get_recipe_ingredients(const int id);
-int db_get_ingredient_id(const std::string &name);
+	inline int get_ingredient_id(const std::string &name) {
-static inline bool db_ingredient_exists(const std::string &name) {
+		return table_get_id_by_name("ingredients", name);
-	return (db_get_ingredient_id(name) > 0);
+	}
+	inline bool db_ingredient_exists(const std::string &name) {
+		return (get_ingredient_id(name) > 0);
 	}
 
 	/**
@@ -70,12 +85,15 @@ static inline bool db_ingredient_exists(const std::string &name) {
 	 *
 	 * @return ID of newly created tag, -1 if DB isn't open, -2 on other failure.
 	 */
-int db_add_tag(const std::string &name);
+	int add_tag(const std::string &name);
-std::vector<std::string> db_get_recipe_tags(const int id);
+	std::vector<std::string> get_recipe_tags(const int id);
-int db_get_tag_id(const std::string &name);
+	inline int get_tag_id(const std::string &name) {
-static inline bool db_tag_exists(const std::string &name) {
+		return table_get_id_by_name("tags", name);
-	return (db_get_tag_id(name) > 0);
+	}
+	inline bool tag_exists(const std::string &name) {
+		return (get_tag_id(name) > 0);
 	}
 
-int db_conn_recipe_ingredient(int recipe_id, int ingredient_id);
+	void conn_recipe_ingredient(int recipe_id, int ingredient_id);
-int db_conn_recipe_tag(int recipe_id, int tag_id);
+	void conn_recipe_tag(int recipe_id, int tag_id);
+};

src/main.cpp

@@ -16,8 +16,9 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <iostream>
 #include <cstdlib>
+#include <exception>
+#include <iostream>
 #include <string>
 
 #include "arg_parse.hpp"
@@ -35,18 +36,19 @@ int main(int argc, char *argv[]) {
 
 	id = parse_args(argv[1]);
 
+	try {
 		switch(id) {
 		case CMD_ADD:
-		ret = command_add();
+			ret = cmd_add();
 			break;
 		case CMD_LIST:
-		ret = command_list(argc - 1, argv + 1);
+			ret = cmd_list(argc - 1, argv + 1);
 			break;
 		case CMD_DEL:
-		ret = command_delete(argc - 2, argv + 2);
+			ret = cmd_delete(argc - 2, argv + 2);
 			break;
 		case CMD_INFO:
-		ret = command_info(std::stoi(argv[2]));
+			ret = cmd_info(std::stoi(argv[2]));
 			break;
 		case CMD_HELP:
 			print_help();
@@ -57,7 +59,12 @@ int main(int argc, char *argv[]) {
 		default:
 			std::cerr << "No such command '" << argv[1] << "'. Use 'help' sub-command." << std::endl;
 			print_usage();
-		return EXIT_FAILURE;
+			ret = EXIT_FAILURE;
+			break;
+		}
+	} catch(const std::exception &e) {
+		std::cerr << e.what() << std::endl;
+		ret = EXIT_FAILURE;
 	}
 
 	return ret;