module CalendarDateSelect
  VERSION = '1.16'

  FORMATS = {
    :natural => {
      :date => "%B %d, %Y",
      :time => " %I:%M %p"
    },
    :hyphen_ampm => {
      :date => "%Y-%m-%d",
      :time => " %I:%M %p",
      :javascript_include => "format_hyphen_ampm"
    },
    :iso_date => {
      :date => "%Y-%m-%d",
      :time => " %H:%M",
      :javascript_include => "format_iso_date"
    },
    :finnish => {
      :date => "%d.%m.%Y",
      :time => " %H:%M",
      :javascript_include => "format_finnish"
    },
    :danish => {
      :date => "%d/%m/%Y",
      :time => " %H:%M",
      :javascript_include => "format_danish"
    },
    :american => {
      :date => "%m/%d/%Y",
      :time => " %I:%M %p",
      :javascript_include => "format_american"
    },
    :euro_24hr => {
      :date => "%d %B %Y",
      :time => " %H:%M",
      :javascript_include => "format_euro_24hr"
    },
    :euro_24hr_ymd => {
      :date => "%Y.%m.%d",
      :time => " %H:%M",
      :javascript_include => "format_euro_24hr_ymd"
    },
    :italian => {
      :date => "%d/%m/%Y",
      :time => " %H:%M",
      :javascript_include => "format_italian"
    },
    :db => {
      :date => "%Y-%m-%d",
      :time => " %H:%M",
      :javascript_include => "format_db"
    }
  }

  # Returns the default_options hash.  These options are by default provided to every calendar_date_select control, unless otherwise overrided.
  # 
  # Example:
  #   # At the bottom of config/environment.rb:
  #   CalendarDateSelect.default_options.update(
  #     :popup => "force",
  #     :month_year => "label",
  #     :image => "custom_calendar_picker.png"
  #   )
  def self.default_options
    @calendar_date_select_default_options ||= { :image => "calendar_date_select/calendar.gif" }
  end

  # Set the picker image.  Provide the image url the same way you would provide it to image_tag
  def self.image=(value)
    default_options[:image] = value
  end

  # Returns the options for the given format
  #
  # Example:
  #   CalendarDateSelect.format = :italian
  #   puts CalendarDateSelect.format[:date]
  #     => "%d/%m/%Y"
  def self.format
    @calendar_date_select_format ||= FORMATS[:natural]
  end

  # Set the format.  To see a list of available formats, CalendarDateSelect::FORMATS.keys, or open lib/calendar_date_select/calendar_date_select.rb
  #
  # (e.g. CalendarDateSelect.format = :italian)
  def self.format=(format)
    raise "CalendarDateSelect: Unrecognized format specification: #{format}" unless FORMATS.has_key?(format)
    @calendar_date_select_format = FORMATS[format]
  end

  def self.date_format_string(time = false)
    format[:date] + (time ? format[:time] : "")
  end

  def self.format_date(date)
    if date.is_a?(Date)
      date.strftime(date_format_string(false))
    else
      date.strftime(date_format_string(true))
    end
  end

  def self.format_time(value, options = {})
    return value unless value.respond_to?("strftime")
    if options[:time]
      format_date(value)
    else
      format_date(value.to_date)
    end
  end

  # Detects the presence of time in a date, string
  def self.has_time?(value)
    case value
    when DateTime, Time then true
    when Date           then false
    else
      /[0-9]:[0-9]{2}/.match(value.to_s) ? true : false
    end
  end
end