module PgShrink

# File lib/pg_shrink.rb, line 18
def self.blank_options
  {
    url: nil,
    config: 'Shrinkfile',
    force: false,
    batch_size: 10000,
    log: true,
  }
end

# File lib/pg_shrink.rb, line 47
def self.run(options)
  unless File.exists?(options[:config])
    if options[:config] == 'Shrinkfile'
      abort("Error loading Shrinkfile: " +
            "Please specify location using -c <path/to/Shrinkfile>")
    else
      abort("Error loading Shrinkfile: " +
            "Could not find file at: #{options[:config]}")
    end
  end

  validate_pg_url!(options[:url])
  batch_size = options[:batch_size].to_i
  unless batch_size >= 1
    abort("Batch size must be at least 1.  #{options[:batch_size]} is invalid!")
  end

  database = PgShrink::Database::Postgres.new(postgres_url: options[:url],
                                              batch_size: batch_size,
                                              log: options[:log])

  database.instance_eval(File.read(options[:config]), options[:config], 1)

  # TODO: Figure out how to write a spec for this.
  unless options[:force] == true
    puts 'WARNING:  pg_shrink is destructive!  It will change this database in place.'
    puts 'Are you sure you want to continue? (y/N)'
    cont = gets
    cont = cont.strip
    unless cont == 'y' || cont == 'Y'
      abort('Aborting!')
    end
  end

  database.shrink!
end

# File lib/pg_shrink.rb, line 28
def self.validate_pg_url!(url)
  if url.blank?
    abort("Error loading postgres: " +
          "Please specify postgres url using -u <postgres_url>")
  end
  uri = URI.parse(url)
  if uri.scheme == 'postgres' && uri.path != '/'
    return true
  else
    abort("Error loading postgres: " +
          "#{url} is not a valid postgres url")
  end
rescue => ex
  abort(
    "Error loading postgres: " +
    "#{url} is not a valid postgres url"
  )
end