'''
Overwatch Aggregate Object type

TODO Method overrides: _common gets renamed to _call_all and we add _call_last.
'''

class ModuleCollision(Exception):
	def __init__(self, colliding_module_name, resident_module_names, item_type, items):
		self.colliding_module_name = colliding_module_name
		self.resident_module_names = resident_module_names
		self.item_type = item_type
		self.items = items
	
	def __str__(self):
		if self.item_type == 'name':
			return "Unable to link module '%s': name already present in Aggregate." %(self.colliding_module_name)
		else:
			return "Unable to link module '%s': %s(s) '%s' already provided by module(s) '%s'." %(self.colliding_module_name,
				self.item_type, "', '".join(self.items), "', '".join(self.resident_module_names))

class ModuleDependencyError(Exception):
	def __init__(self, module_name, dependencies, unlink=False):
		self.module_name = module_name
		self.dependencies = dependencies
		self.unlink = unlink
	
	def __str__(self):
		if self.unlink:
			return "Unable to unlink module '%s': Aggregate depends on its export(s) '%s'." %(self.module_name,
			"', '".join(self.dependencies))
		else:
			return "Unable to link module '%s': requirement '%s' unsatisfied by Aggregate." %(self.module_name,
			"', '".join(self.dependencies))

class CommonMethodMissing(Exception):
	def __init__(self, method_name, module_name):
		self.method_name = method_name
		self.module_name = module_name
	
	def __str__(self):
		return "Unable to link module '%s': method '%s' (declared as common) does not exist in module." %(
			self.module_name, self.method_name)

class ModuleDoesntExist(Exception):
	def __init__(self, module_name):
		self.module_name = module_name
	
	def __str__(self):
		return "Unable to unlink module '%s': not linked to Aggregate." %(self.module_name)