Join House Bloc

is_available = government_has_flag = government_has_house_blocs
trigger_if = {
	limit = {
		is_ai = yes
	}
	OR = {
		is_landed = yes
		tgp_is_ceremonial_liege_trigger = yes
	}
}
house.house_head ?= this
tgp_house_bloc_interaction_valid_trigger = yes
NOT = {
	has_character_flag = recently_joined_bloc
}
is_shown = scope:recipient != scope:actor
scope:recipient = {
	exists = house.house_confederation
	tgp_house_bloc_interaction_valid_trigger = yes
	trigger_if = {
		limit = {
			exists = scope:actor.house.house_confederation
		}
		NOT = {
			house.house_confederation = scope:actor.house.house_confederation
		}
	}
}
trigger_if = {
	limit = {
		scope:actor = {
			is_ai = yes
		}
	}
	scope:recipient = {
		house.house_head ?= this
		OR = {
			is_landed = yes
			tgp_is_ceremonial_liege_trigger = yes
		}
	}
}

As written in game/common/character_interactions/10_tgp_japan_interactions.txt.

scope:actor = {
	trigger_if = {
		limit = {
			is_at_war_with = scope:recipient
		}
		custom_tooltip = {
			text = join_bloc_war_tt
			any_character_war = {
				using_cb = japan_install_bloc_member_cb
				primary_attacker = scope:recipient
				primary_defender = scope:actor
			}
		}
	}
	tgp_house_bloc_interaction_valid_showing_failures_trigger = yes
	custom_tooltip = {
		text = join_bloc_left_cooldown_tt
		NOT = {
			house = {
				any_in_list = {
					variable = left_bloc_cooldown
					scope:recipient.house.house_confederation ?= this
				}
			}
		}
	}
	custom_tooltip = {
		text = join_bloc_already_leading_another_tt
		exists = house
		NOT = {
			confederation.leading_house ?= house
		}
	}
	NAND = {
		is_ai = yes
		scope:recipient = {
			has_character_flag = join_house_bloc_ai_send_cooldown
		}
	}
}
scope:recipient = {
	tgp_house_bloc_interaction_valid_showing_failures_trigger = yes
}

As written in game/common/character_interactions/10_tgp_japan_interactions.txt.

on_send = if = {
	limit = {
		scope:actor = {
			is_ai = yes
		}
	}
	scope:recipient = {
		add_character_flag = {
			flag = join_house_bloc_ai_send_cooldown
			months = 3
		}
	}
}
debug_log = join_house_bloc
debug_log_scopes = yes
on_accept = scope:actor = {
	if = {
		limit = {
			scope:hook = yes
		}
		scope:actor = {
			use_hook = scope:recipient
		}
	}
	else = {
		if = {
			limit = {
				scope:gold = yes
			}
			pay_short_term_gold = {
				target = scope:recipient
				gold = scope:recipient.medium_gold_value
			}
		}
		if = {
			limit = {
				scope:prestige = yes
			}
			add_prestige = scope:recipient.medium_prestige_loss
			scope:recipient = {
				add_prestige = medium_prestige_value
			}
		}
		if = {
			limit = {
				scope:influence = yes
			}
			change_influence = scope:recipient.medium_gold_value_negative
			scope:recipient = {
				change_influence = medium_gold_value
			}
		}
	}
	if = {
		limit = {
			is_confederation_member = yes
		}
		house = {
			tgp_save_bloc_leaving_reason_effect = {
				LEAVING_HOUSE = scope:actor.house
				INVITING_HOUSE = scope:recipient.house
			}
			tgp_leave_house_bloc_effect = {
				OPINION = flag:yes
				TRUCE = flag:no
			}
		}
	}
}
scope:recipient.house = {
	if = {
		limit = {
			NOT = {
				exists = house_confederation
			}
		}
		tgp_create_house_bloc_effect = {
			TYPE = none
		}
	}
}
scope:actor = {
	house = {
		tgp_join_house_bloc_effect ?= {
			INVITER = scope:recipient.house
			OPINION = flag:yes
		}
	}
	if = {
		limit = {
			scope:hook = yes
		}
		add_character_flag = {
			flag = forced_bloc_membership
			years = 10
		}
		custom_tooltip = forced_bloc_membership_tt
	}
}

As written in game/common/character_interactions/10_tgp_japan_interactions.txt.