const std = @import("std");

/// Configure a "one to one" relationship.
pub const OneConfiguration = union(enum) {
	/// Direct one-to-one relationship using a local foreign key.
	direct: struct {
		/// The local foreign key name.
		foreignKey: []const u8,
		/// Associated model key name.
		/// Use the default key name of the associated model.
		modelKey: ?[]const u8 = null,
	},

	/// Reverse one-to-one relationship using distant foreign key.
	reverse: struct {
		/// The distant foreign key name.
		/// Use the default key name of the related model.
		foreignKey: ?[]const u8 = null,
		/// Current model key name.
		/// Use the default key name of the current model.
		modelKey: ?[]const u8 = null,
	},

	/// Used when performing a one-to-one relationship through an association table.
	through: struct {
		/// Name of the join table.
		table: []const u8,
		/// The local foreign key name.
		/// Use the default key name of the current model.
		foreignKey: ?[]const u8 = null,
		/// The foreign key name in the join table.
		joinForeignKey: []const u8,
		/// The model key name in the join table.
		joinModelKey: []const u8,
		/// Associated model key name.
		/// Use the default key name of the associated model.
		modelKey: ?[]const u8 = null,
	},
};

/// Type of a related model field.
pub const Model = struct {
	/// Name of the related model definition.
	related: []const u8,

	/// Configuration of the relationship.
	relationship: OneConfiguration,
};





/// Configure a "one to many" or "many to many" relationship.
pub const ManyConfiguration = union(enum) {
	/// Direct one-to-many relationship using a distant foreign key.
	direct: struct {
		/// The distant foreign key name pointing to the current model.
		foreignKey: []const u8,
		/// Current model key name.
		/// Use the default key name of the current model.
		modelKey: ?[]const u8 = null,
	},

	/// Used when performing a many-to-many relationship through an association table.
	through: struct {
		/// Name of the join table.
		table: []const u8,
		/// The local foreign key name.
		/// Use the default key name of the current model.
		foreignKey: ?[]const u8 = null,
		/// The foreign key name in the join table.
		joinForeignKey: []const u8,
		/// The model key name in the join table.
		joinModelKey: []const u8,
		/// Associated model key name.
		/// Use the default key name of the associated model.
		modelKey: ?[]const u8 = null,
	},
};

/// Type of related models collection field.
pub const Models = struct {
	/// Name of the related model definition.
	related: []const u8,

	/// Configuration of the relationship.
	relationship: OneConfiguration,
};