84 lines
2.3 KiB
Ruby

require 'RMagick'
require 'base64'
module ReallySimpleCaptcha::Captcha
module PlainCaptcha
DEFAULT_OPTIONS = {
width: 120,
height: 40,
wave_amplitude: 4.0,
wave_length: 60.0,
implode_amount: 0.2,
pointsize: 22,
text_fill: 'darkblue',
background_color: 'white'
}
include ActiveSupport::Configurable
config_accessor :field_name
config_accessor :width
config_accessor :height
config_accessor :implode_amount
config_accessor :wave_amplitude
config_accessor :wave_length
config_accessor :pointsize
config_accessor :fill
config_accessor :background_color
config_accessor :text_length
config.field_name = :plain_captcha
config.text_length = 6
def self.configure(&block)
yield config
end
module ViewHelpers
def plain_captcha_tag
session[PlainCaptcha.field_name] = ReallySimpleCaptcha::Util.random_string(PlainCaptcha.text_length)
image = PlainCaptcha.generate_image(session[:plain_captcha],
PlainCaptcha.config.select { |k,v| DEFAULT_OPTIONS.has_key?(k) })
content_tag :div, class: 'plain_captcha' do
html = image_tag "data:image/gif;base64,#{image}", alt: "Captcha"
html.concat text_field_tag PlainCaptcha.field_name, nil, required: 'required', autocomplete: 'off'
html
end
end
end
module ControllerHelpers
def plain_captcha_valid?
res = params[PlainCaptcha.field_name] == session[PlainCaptcha.field_name]
session[PlainCaptcha.field_name] = nil
res
end
end
def self.generate_image(captcha_text, args={})
options = DEFAULT_OPTIONS.merge(args)
image = ::Magick::Image.new(options[:width], options[:height]) do
self.background_color = options[:background_color]
end
text = ::Magick::Draw.new do
self.pointsize = options[:pointsize]
self.gravity = ::Magick::CenterGravity
self.fill = options[:text_fill]
end
text.annotate(image, 0, 0, 0, 0, captcha_text)
image = image.wave(options[:wave_amplitude], options[:wave_length]).implode(options[:implode_amount])
Base64.strict_encode64(image.to_blob { self.format = 'GIF' })
end
end
end