select_fallback_pool_to_move_to_effect

select_fallback_pool_to_move_to_effect = {
	if = {
		limit = {
			NOT = { exists = location }
		}
		random_duchy = {
			limit = {
				exists = title_capital_county
				title_capital_county.culture = {
					has_same_culture_heritage = scope:mover.culture
				}
			}
			title_capital_county.holder.capital_province = { save_scope_as = destination }
		}
		if = {
			limit = {
				NOT = { exists = scope:destination }
			}
			random_duchy = {
				limit = {
					exists = title_capital_county
					title_capital_county.faith = scope:mover.faith
				}
				title_capital_county.holder.capital_province = { save_scope_as = destination }
			}
		}
		if = {
			limit = {
				NOT = { exists = scope:destination }
			}
			random_duchy = {
				limit = {
					exists = title_capital_county.holder.capital_province
				}
				title_capital_county.holder.capital_province = { save_scope_as = destination }
			}
		}
	}
	else = {
		random_kingdom = {
			limit = {
				is_titular = no
				title_capital_county.title_province ?= {
					squared_distance = {
						target = scope:mover.location value <= squared_distance_large
					}
				}
			}
			random_in_de_jure_hierarchy = {
				limit = {
					tier = tier_duchy
					title_capital_county.holder.capital_province = { local_pool_is_full_trigger = no }
				}
				title_capital_county.holder.capital_province = { save_scope_as = destination }
			}
		}
		if = {
			limit = {
				NOT = { exists = scope:destination }
				exists = scope:mover.host.capital_province
			}
			scope:mover.host.capital_province = { save_scope_as = destination }
		}
		else_if = {
			limit = {
				NOT = { exists = scope:destination }
			}
			random_kingdom = {
				limit = {
					exists = title_capital_county
				}
				title_capital_county.holder.capital_province = { save_scope_as = destination }
			}
		}
	}
}

As written in game/common/scripted_effects/00_courtier_guest_management_effects.txt.