module ActiveRecord
module Associations
class HasAndBelongsToManyAssociation < AssociationCollection #:nodoc:
def initialize(owner, association_name, association_class_name, association_class_primary_key_name, options)
super
@association_foreign_key = options[:association_foreign_key] || Inflector.underscore(Inflector.demodulize(association_class_name)) + "_id"
@association_table_name = options[:table_name] || @association_class.table_name
@join_table = options[:join_table]
@order = options[:order] || "t.#{@association_class.primary_key}"
construct_sql
end
def build(attributes = {})
load_target
record = @association_class.new(attributes)
@target << record
record
end
# Removes all records from this association. Returns +self+ so method calls may be chained.
def clear
return self if size == 0 # forces load_target if hasn't happened already
if sql = @options[:delete_sql]
each { |record| @owner.connection.execute(sql) }
elsif @options[:conditions]
sql =
"DELETE FROM #{@join_table} WHERE #{@association_class_primary_key_name} = #{@owner.quoted_id} " +
"AND #{@association_foreign_key} IN (#{collect { |record| record.id }.join(", ")})"
@owner.connection.execute(sql)
else
sql = "DELETE FROM #{@join_table} WHERE #{@association_class_primary_key_name} = #{@owner.quoted_id}"
@owner.connection.execute(sql)
end
@target = []
self
end
def find_first
load_target.first
end
def find(*args)
# Return an Array if multiple ids are given.
expects_array = args.first.kind_of?(Array)
ids = args.flatten.compact.uniq
# If no block is given, raise RecordNotFound.
if ids.empty?
raise RecordNotFound, "Couldn't find #{@association_class.name} without an ID#{conditions}"
# If using a custom finder_sql, scan the entire collection.
elsif @options[:finder_sql]
if ids.size == 1
id = ids.first
record = load_target.detect { |record| id == record.id }
expects_array? ? [record] : record
else
load_target.select { |record| ids.include?(record.id) }
end
# Otherwise, construct a query.
else
ids_list = ids.map { |id| @owner.send(:quote, id) }.join(',')
records = find_target(@finder_sql.sub(/ORDER BY/, "AND j.#{@association_foreign_key} IN (#{ids_list}) ORDER BY"))
if records.size == ids.size
if ids.size == 1 and !expects_array
records.first
else
records
end
else
raise RecordNotFound, "Couldn't find #{@association_class.name} with ID in (#{ids_list})"
end
end
end
def push_with_attributes(record, join_attributes = {})
raise_on_type_mismatch(record)
join_attributes.each { |key, value| record[key.to_s] = value }
insert_record(record) unless @owner.new_record?
@target << record
self
end
alias :concat_with_attributes :push_with_attributes
def size
@options[:uniq] ? count_records : super
end
protected
def find_target(sql = @finder_sql)
records = @association_class.find_by_sql(sql)
@options[:uniq] ? uniq(records) : records
end
def count_records
load_target.size
end
def insert_record(record)
return false unless record.save
if @options[:insert_sql]
@owner.connection.execute(interpolate_sql(@options[:insert_sql], record))
else
columns = @owner.connection.columns(@join_table, "#{@join_table} Columns")
attributes = columns.inject({}) do |attributes, column|
case column.name
when @association_class_primary_key_name
attributes[column.name] = @owner.quoted_id
when @association_foreign_key
attributes[column.name] = record.quoted_id
else
value = record[column.name]
attributes[column.name] = value unless value.nil?
end
attributes
end
sql =
"INSERT INTO #{@join_table} (#{@owner.send(:quoted_column_names, attributes).join(', ')}) " +
"VALUES (#{attributes.values.collect { |value| @owner.send(:quote, value) }.join(', ')})"
@owner.connection.execute(sql)
end
return true
end
def delete_records(records)
if sql = @options[:delete_sql]
records.each { |record| @owner.connection.execute(sql) }
else
ids = quoted_record_ids(records)
sql = "DELETE FROM #{@join_table} WHERE #{@association_class_primary_key_name} = #{@owner.quoted_id} AND #{@association_foreign_key} IN (#{ids})"
@owner.connection.execute(sql)
end
end
def construct_sql
interpolate_sql_options!(@options, :finder_sql, :delete_sql)
@finder_sql = @options[:finder_sql] ||
"SELECT t.*, j.* FROM #{@association_table_name} t, #{@join_table} j " +
"WHERE t.#{@association_class.primary_key} = j.#{@association_foreign_key} AND " +
"j.#{@association_class_primary_key_name} = #{@owner.quoted_id} " +
(@options[:conditions] ? " AND " + interpolate_sql(@options[:conditions]) : "") + " " +
"ORDER BY #{@order}"
end
end
end
end