Call to War

is_available = is_at_war = yes
is_shown = scope:actor = {
	trigger_if = {
		limit = {
			is_ai = yes
		}
		scope:recipient.current_military_strength >= 100
	}
	trigger_if = {
		limit = {
			liege = scope:recipient
		}
		subject_contract_has_flag = vassal_contract_liege_forced_war_override
	}
	trigger_if = {
		limit = {
			scope:recipient = {
				is_tributary_of = scope:actor
				NOT = {
					is_allied_to = scope:actor
				}
			}
		}
		has_realm_law_flag = can_call_tributaries_for_piety
		piety >= 50
	}
}
scope:recipient = {
	OR = {
		is_allied_to = scope:actor
		AND = {
			this ?= scope:actor.diarch
			scope:actor = {
				any_character_war = {
					diarch_callable_in_internal_war_trigger = yes
				}
			}
		}
		scope:actor = {
			is_vassal_of = prev
			subject_contract_has_flag = vassal_contract_liege_forced_war_override
		}
		scope:actor = {
			is_tributary_of = prev
			subject_contract_has_flag = tributary_contract_suzerain_guarantee_override
		}
		AND = {
			is_tributary_of = scope:actor
			scope:actor = {
				piety >= 50
				has_realm_law_flag = can_call_tributaries_for_piety
			}
		}
	}
}
scope:actor = {
	NOT = {
		is_character_interaction_valid = {
			recipient = scope:recipient
			interaction = call_house_member_to_war_interaction
		}
	}
}

As written in game/common/character_interactions/00_alliance.txt.

scope:recipient = {
	is_ruler = yes
	custom_tooltip = {
		text = too_low_rank_to_call_hegemon
		trigger_if = {
			limit = {
				highest_held_title_tier = tier_hegemony
			}
			scope:actor = {
				highest_held_title_tier >= tier_empire
			}
		}
	}
}
scope:actor = {
	custom_description = {
		text = must_be_war_leader
		any_character_war = {
			is_war_leader = scope:actor
		}
	}
	custom_description = {
		text = cannot_call_same_character_multiple_times
		object = scope:recipient
		any_character_war = {
			ALL_FALSE = {
				was_called = scope:recipient
				is_participant = scope:recipient
			}
		}
	}
	trigger_if = {
		limit = {
			faith != scope:recipient.faith
		}
		custom_description = {
			text = is_of_wrong_faith_for_holy_war
			subject = scope:actor
			object = scope:recipient
			any_character_war = {
				NOR = {
					using_cb = undirected_great_holy_war
					using_cb = directed_great_holy_war
				}
			}
		}
	}
}
can_potentially_call_ally_trigger = {
	WARRIOR = scope:actor
	JOINER = scope:recipient
}

As written in game/common/character_interactions/00_alliance.txt.

on_accept = call_ally_interaction_effect = yes
save_scope_value_as = {
	name = call_ally_interaction
	value = yes
}
scope:actor = {
	hidden_effect = {
		if = {
			limit = {
				NOR = {
					has_relation_friend = scope:recipient
					has_relation_potential_friend = scope:recipient
				}
			}
			set_relation_potential_friend = scope:recipient
		}
	}
	trigger_event = call_ally.0100
}
scope:target = {
	if = {
		limit = {
			is_religious_war = yes
			scope:recipient = {
				any_active_accolade = {
					accolade_parameter = acclaimed_knight_piety_from_battle
				}
			}
		}
		scope:recipient = {
			add_piety = minor_piety_gain
		}
	}
	if = {
		limit = {
			is_religious_war = yes
			scope:recipient = {
				any_active_accolade = {
					accolade_parameter = acclaimed_knight_piety_from_battle_high
				}
			}
		}
		scope:recipient = {
			add_piety = medium_piety_gain
		}
	}
}
on_decline = if = {
	limit = {
		exists = scope:target
	}
	scope:target = {
		if = {
			limit = {
				is_attacker = scope:actor
			}
			scope:actor = {
				add_opinion = {
					modifier = rejected_call_to_offensive_war
					target = scope:recipient
				}
			}
			scope:recipient = {
				if = {
					limit = {
						NOT = {
							government_has_flag = government_is_mandala
						}
					}
					add_prestige_experience = major_prestige_loss
				}
			}
		}
		else = {
			scope:actor = {
				add_opinion = {
					modifier = rejected_call_to_defensive_war
					target = scope:recipient
				}
			}
			scope:recipient = {
				if = {
					limit = {
						government_has_flag = government_is_mandala
					}
					add_prestige_experience = major_prestige_loss
					add_piety_level = -1
				}
				else = {
					add_prestige_experience = massive_prestige_loss
				}
			}
		}
		if = {
			limit = {
				scope:actor = {
					has_relation_blood_brother = scope:recipient
				}
			}
			scope:recipient = {
				add_piety_experience = massive_piety_loss
				add_character_modifier = {
					modifier = broke_blood_brotherhood_modifier
					desc = broke_blood_brotherhood_modifier_acceptance_tt
					years = 25
				}
				remove_relation_blood_brother = scope:actor
			}
			scope:actor = {
				set_relation_rival = {
					target = scope:recipient
					reason = rival_blood_brother_refused_call_reason
				}
			}
		}
		if = {
			limit = {
				scope:recipient = scope:actor.obedience_target
				scope:actor = {
					OR = {
						subject_contract_has_flag = vassal_contract_liege_forced_war_override
						subject_contract_has_flag = tributary_contract_suzerain_guarantee_override
					}
				}
			}
			scope:actor = {
				set_variable = {
					name = not_obedient_declined_call
					value = scope:recipient
					years = 5
				}
			}
		}
		if = {
			limit = {
				scope:recipient = scope:actor.suzerain
				is_defender = scope:actor
				scope:actor = {
					subject_contract_has_flag = tributary_contract_suzerain_guarantee_override
				}
			}
			scope:actor = {
				end_tributary = yes
			}
		}
		hidden_effect = {
			if = {
				limit = {
					NOT = {
						was_called = scope:recipient
					}
				}
				set_called_to = scope:recipient
			}
		}
	}
	scope:actor = {
		trigger_event = call_ally.0101
	}
	refuse_call_to_arms_add_clan_unity_effect = yes
	scope:recipient = {
		if = {
			limit = {
				exists = house
				is_house_head = yes
				exists = scope:actor.house
			}
			house = {
				change_house_relation_effect = {
					HOUSE = scope:actor.house
					VALUE = house_relation_damage_medium_value
					REASON = ally_call_ignored
					CHAR = scope:recipient
					TARGET_CHAR = scope:actor
					TITLE = scope:dummy_gender
				}
			}
		}
	}
}
on_auto_accept = scope:recipient = {
	trigger_event = call_ally.0001
}
scope:target = {
	if = {
		limit = {
			is_religious_war = yes
			scope:recipient = {
				any_active_accolade = {
					accolade_parameter = acclaimed_knight_piety_from_battle
				}
			}
		}
		scope:recipient = {
			add_piety = miniscule_piety_gain
		}
	}
	if = {
		limit = {
			is_religious_war = yes
			scope:recipient = {
				any_active_accolade = {
					accolade_parameter = acclaimed_knight_piety_from_battle_high
				}
			}
		}
		scope:recipient = {
			add_piety = minor_piety_gain
		}
	}
}

As written in game/common/character_interactions/00_alliance.txt.