module DataJanitor

# File lib/data_janitor/data_janitor.rb, line 2
def self.audit(output_file, verbose, unscoped, options)
  output = {}
  all_models.each do |ar_model|
    begin
      audit_model ar_model, output, verbose, unscoped, options
    rescue ActiveRecord::StatementInvalid # used to catch HABTM and schema migration. Only care about real Models
      puts "skipping #{ar_model}"
    end
  end

  File.write(output_file, output.to_json)

  puts "Wrote results to #{output_file}"
end

# File lib/data_janitor/data_janitor.rb, line 17
def self.audit_model(model, output = {}, verbose = false, unscoped = false, options = 'no-type-check')
  total = 0
  failed = 0
  puts "Validating: #{model.name}"
  output[model.name] = {}

  model = model.unscoped if unscoped
  model.include(DataJanitor::UniversalValidator)
  model.validate do |record|
    record.validate_field_values options
  end

  model.find_each do |rec|
    if rec.invalid?(:dj_audit)
      rec.errors.to_h.each_pair do |attribute, error_message|
        output[model.name][attribute] ||= {}
        output[model.name][attribute][error_message] ||= []
        output[model.name][attribute][error_message] << rec.id
      end

      failed += 1
    end

    total += 1
  end

  puts output.to_json if verbose
  puts "Completed #{total} records with #{failed} failures"
end

# File lib/data_janitor/data_janitor.rb, line 47
def self.cleanse
  all_models.each do |ar_model|
    cleanse_model! ar_model
  end
end

# File lib/data_janitor/data_janitor.rb, line 53
def self.cleanse_model(model)
  cleanse_model! model.constantize
end

# File lib/data_janitor/data_janitor.rb, line 59
def self.all_models
  # Needs this executed before here: Rails.application.eager_load!
  ActiveRecord::Base.descendants
end

# File lib/data_janitor/data_janitor.rb, line 74
def self.clean_nils_from!(model, columns, default)
  columns.each do |column|
    count = model.where(column.name => nil).update_all(column.name => default)
    puts "Fixed #{count} #{model} records where #{column.name} was nil" if count > 0
  end
end

# File lib/data_janitor/data_janitor.rb, line 64
def self.cleanse_model!(model)
  string_columns = model.columns.select{|c| (c.type == :string || c.type == :text) && c.array == false}
  boolean_columns = model.columns.select{|c| c.type == :boolean && c.array == false}
  array_columns = model.columns.select{|c| c.array == true}

  clean_nils_from! model, string_columns, ""
  clean_nils_from! model, boolean_columns, false
  clean_nils_from! model, array_columns, []
end