feat: added component default values (#889)

Co-authored-by: Craig Edwards (Brain) <braindigitalis@users.noreply.github.com>

include/dpp/message.h

@@ -80,6 +80,31 @@ enum component_style : uint8_t {
 	cos_link
 };
 
+/**
+ * Represents the type of a dpp::component_default_value
+ *
+ * @note They're different to discord's value types
+ */
+enum component_default_value_type: uint8_t {
+	cdt_user = 0,
+	cdt_role = 1,
+	cdt_channel = 2,
+};
+
+/**
+ * @brief A Default value structure for components
+ */
+struct DPP_EXPORT component_default_value {
+	/**
+	 * @brief The type this default value represents
+	 */
+	component_default_value_type type;
+	/**
+	 * @brief Default value. ID of a user, role, or channel
+	 */
+	dpp::snowflake id;
+};
+
 /**
  * @brief An option for a select component
  */
@@ -295,6 +320,13 @@ class DPP_EXPORT component : public json_interface<component> {
 	 */
 	std::vector<uint8_t> channel_types;
 
+	/**
+	 * List of default values for auto-populated select menu components. The amount of default values must be in the range defined by dpp::component::min_value and dpp::component::max_values.
+	 *
+	 * @note Only available for auto-populated select menu components, which include dpp::cot_user_selectmenu, dpp::cot_role_selectmenu, dpp::cot_mentionable_selectmenu, and dpp::cot_channel_selectmenu components.
+	 */
+	std::vector<component_default_value> default_values;
+
 	/** Disabled flag (for buttons)
 	 */
 	bool disabled;
@@ -503,6 +535,14 @@ class DPP_EXPORT component : public json_interface<component> {
 	 */
 	component& add_component(const component& c);
 
+	/**
+ 	 * @brief Add a default value.
+ 	 *
+ 	 * @param id Default value. ID of a user, role, or channel
+ 	 * @param type The type this default value represents
+ 	 */
+	component& add_default_value(const snowflake id, const component_default_value_type type);
+
 	/**
 	 * @brief Set the emoji of the current sub-component.
 	 * Only valid for buttons. Adding an emoji to a component

src/dpp/message.cpp

@@ -58,6 +58,14 @@ component& component::fill_from_json_impl(nlohmann::json* j) {
 	if (j->contains("max_values") && j->at("max_values").is_number_integer()) {
 		max_values = j->at("max_values").get<int32_t>();
 	}
+	if (j->contains("default_values") && !j->at("default_values").is_null()) {
+		for (auto const &v : j->at("default_values")) {
+			component_default_value d;
+			d.id = snowflake_not_null(&v, "id");
+			d.type = static_cast<component_default_value_type>(int8_not_null(&v, "type"));
+			default_values.push_back(d);
+		}
+	}
 	if (type == cot_action_row) {
 		set_object_array_not_null<component>(j, "components", components);
 	} else if (type == cot_button) { // button specific fields
@@ -338,6 +346,21 @@ void to_json(json& j, const component& cp) {
 		if (cp.max_values >= 0) {
 			j["max_values"] = cp.max_values;
 		}
+		if (!cp.default_values.empty()) {
+			j["default_values"] = json::array();
+			for (auto const &v : cp.default_values) {
+				json o;
+				o["id"] = v.id;
+				if (v.type == dpp::cdt_role) {
+					o["type"] = "role";
+				} else if (v.type == dpp::cdt_channel) {
+					o["type"] = "channel";
+				} else if (v.type == dpp::cdt_user) {
+					o["type"] = "user";
+				}				
+				j["default_values"].push_back(o);
+			}
+		}
 	} else if (cp.type == cot_channel_selectmenu) {
 		j["custom_id"] = cp.custom_id;
 		j["disabled"] = cp.disabled;
@@ -356,6 +379,21 @@ void to_json(json& j, const component& cp) {
 				j["channel_types"].push_back(type);
 			}
 		}
+		if (!cp.default_values.empty()) {
+			j["default_values"] = json::array();
+			for (auto const &v : cp.default_values) {
+				json o;
+				o["id"] = v.id;
+				if (v.type == dpp::cdt_role) {
+					o["type"] = "role";
+				} else if (v.type == dpp::cdt_channel) {
+					o["type"] = "channel";
+				} else if (v.type == dpp::cdt_user) {
+					o["type"] = "user";
+				}
+				j["default_values"].push_back(o);
+			}
+		}
 	}
 }
 
@@ -439,6 +477,14 @@ component& component::add_select_option(const select_option &option) {
 	return *this;
 }
 
+component &component::add_default_value(const snowflake id, const component_default_value_type type) {
+	component_default_value default_value;
+	default_value.id = id;
+	default_value.type = type;
+	this->default_values.push_back(default_value);
+	return *this;
+}
+
 embed::~embed() = default;
 
 embed::embed() : timestamp(0), color(0) {