fixin.me/app/models/unit.rb

91 lines
3.7 KiB
Ruby

class Unit < ApplicationRecord
belongs_to :user, optional: true
belongs_to :base, optional: true, class_name: "Unit"
has_many :subunits, class_name: "Unit", dependent: :restrict_with_error, inverse_of: :base
validate if: ->{ base.present? } do
errors.add(:base, :user_mismatch) unless user == base.user
errors.add(:base, :multilevel_nesting) if base.base.present?
end
validates :symbol, presence: true, uniqueness: {scope: :user_id},
length: {maximum: columns_hash['symbol'].limit}
validates :name, length: {maximum: columns_hash['name'].limit}
validates :multiplier, numericality: {equal_to: 1}, unless: :base
validates :multiplier, numericality: {other_than: 0}, if: :base
scope :defaults, ->{ where(user: nil) }
scope :defaults_diff, ->{
actionable_units = Arel::Table.new('actionable_units')
units = actionable_units.alias('units')
bases_units = arel_table.alias('bases_units')
other_units = arel_table.alias('other_units')
other_bases_units = arel_table.alias('other_bases_units')
sub_units = arel_table.alias('sub_units')
Unit.with_recursive(actionable_units: [
Unit.with(units: self.or(Unit.defaults)).left_joins(:base)
.where.not(
# Exclude Units that are/have default counterpart
Arel::SelectManager.new.project(1).from(other_units)
.outer_join(other_bases_units)
.on(other_units[:base_id].eq(other_bases_units[:id]))
.where(
other_bases_units[:symbol].is_not_distinct_from(bases_units[:symbol])
.and(other_units[:symbol].eq(arel_table[:symbol]))
.and(other_units[:user_id].is_distinct_from(arel_table[:user_id]))
).exists
)
.select(
arel_table[Arel.star],
# Decide if Unit can be im-/exported based on existing hierarchy:
# * same base unit symbol has to exist
# * unit with subunits can only be ported to root
arel_table[:base_id].eq(nil).or(
(
Arel::SelectManager.new.project(1).from(other_units)
.join(sub_units).on(other_units[:id].eq(sub_units[:base_id]))
.where(
other_units[:symbol].eq(arel_table[:symbol])
.and(other_units[:user_id].is_distinct_from(arel_table[:user_id]))
).exists.not
).and(
Arel::SelectManager.new.project(1).from(other_bases_units)
.where(
other_bases_units[:symbol].is_not_distinct_from(bases_units[:symbol])
.and(other_bases_units[:user_id].is_distinct_from(bases_units[:user_id]))
).exists
)
).as('portable')
),
# NOTE: turn off ONLY_FULL_GROUP_BY or is it incompatible with other DBs?
# Fill base Units to display proper hierarchy. Duplicates will be removed
# by final group() - can't be deduplicated with UNION due to 'portable' field.
arel_table.join(actionable_units).on(actionable_units[:base_id].eq(arel_table[:id]))
.project(arel_table[Arel.star], Arel::Nodes.build_quoted(nil).as('portable'))
]).select(units: column_names).select(units[:portable].minimum.as('portable'))
.from(units).group(Unit.column_names)
}
scope :ordered, ->{
left_outer_joins(:base)
.order(arel_table.coalesce(Arel::Table.new(:bases_units)[:symbol], arel_table[:symbol]),
arel_table[:base_id].asc.nulls_first, :multiplier, :symbol)
}
before_destroy do
# TODO: disallow destruction if any object depends on this unit
nil
end
def movable?
subunits.empty?
end
def default?
user_id.nil?
end
def exportable?
!default? && (base.nil? || base.default?)
end
end